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DRAFT Conceptual Desalination Feasibility Study Prepared for: Montecito Water District 583 San Ysidro Road Montecito, CA 93108 805.969.2271 Contact: Thomas Mosby, General Manager October 27, 2014 Prepared by: JN 142988 RBF Consulting, a company of Michael Baker International 40810 County Center Drive, Suite 100, Temecula, CA 92591 951.676.8042 www.mbakerintl.com Contact: Paul Findley Kevin Thomas

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DRAFT

Conceptual Desalination Feasibility Study

Prepared for:

Montecito Water District

583 San Ysidro Road Montecito, CA 93108

805.969.2271 Contact: Thomas Mosby, General Manager

October 27, 2014

Prepared by:

JN 142988

RBF Consulting, a company of Michael Baker International 40810 County Center Drive, Suite 100, Temecula, CA 92591 951.676.8042 www.mbakerintl.com Contact: Paul Findley Kevin Thomas

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TABLE OF CONTENTS I. Introduction .................................................................................................................................... 1

A. Introduction and Background............................................................................................................ 1

B. Objectives of Conceptual Feasibility Study ...................................................................................... 2

II. Desalination Plant Conceptual Sizing .......................................................................................... 2

A. Summary of District Water Sources ................................................................................................. 2

B. Summary of District Water Demands ............................................................................................... 4

C. Reliability of Existing Water Supplies .............................................................................................. 5

D. Desalination Plant Operation ............................................................................................................ 8

E. Desalination Plant Capacity .............................................................................................................. 9

III. Feasibility Considerations ........................................................................................................... 10

A. Seawater Intake ............................................................................................................................... 10

B. Concentrate Discharge and Disposal .............................................................................................. 26

C. Desalination Plant ........................................................................................................................... 30

D. Product Water Conveyance ............................................................................................................. 38

E. Project Alternatives ......................................................................................................................... 40

IV. Project Implementation ............................................................................................................... 51

A. Regulatory & Public Considerations ............................................................................................... 51

B. Project Delivery and Schedule Considerations ............................................................................... 55

C. Next Steps ....................................................................................................................................... 58

V. Conclusions and Recommendations ........................................................................................... 60

APPENDICES Appendix A – Offshore Geologic Study Appendix B – Cost Estimate Assumptions

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LIST OF TABLES Table 1 – Long Term Theoretical Available Water Supply .......................................................................... 3 Table 2 – Actual Average District Water Supply (1998 – 2013) .................................................................. 3 Table 3 – District Customer Classifications ................................................................................................. 4 Table 4 – District Demand and Average Rainfall (1998 – 2013) ................................................................. 5 Table 5 – Projected Demand at Full Build-Out ............................................................................................ 6 Table 6 – Projected Shortfalls Due to Drought Conditions .......................................................................... 7 Table 7 – Desalination Plant Operational Scenarios ..................................................................................... 9 Table 8 – Sub-Seafloor Intake Alternatives & Corresponding Lengths ..................................................... 23 Table 9 – Slant Wells at Intake Location I1 ................................................................................................ 23 Table 10 – Concentrate Discharge Outfall Alternatives & Corresponding Lengths ................................... 29 Table 11 – Preliminary Candidate SWRO Plant Sites ................................................................................ 34 Table 12 – SWRO Desalination Plant Site Options .................................................................................... 35 Table 13 – Product Water Conveyance Pipeline Lengths ........................................................................... 40 Table 14 – Feedwater Conveyance Pipeline Analysis ................................................................................ 41 Table 15 – Brine Conveyance Pipeline Analysis ........................................................................................ 42 Table 16 – Summary of SWRO System Alternatives ................................................................................. 43 Table 17 – SWRO System Alternative Considering Slant Wells ............................................................... 44 Table 18 - Implementation Schedule .......................................................................................................... 57

LIST OF FIGURES Figure 1: Slant Well Intake Profile ............................................................................................................ 16 Figure 2: Horizontal Collector Well .......................................................................................................... 17 Figure 3: Excavated Seabed Infiltration Gallery (Fukuoka, Japan) ........................................................... 19 Figure 4: Neodren Sub-Seafloor Drain ...................................................................................................... 21 Figure 5: Open-Ocean Intake with Wedge-Wire Screen ........................................................................... 22 Figure 6: SWRO Membrane Process ......................................................................................................... 30 Figure 7: RO Spiral Wound Membrane Element ....................................................................................... 31 Figure 8: Membrane Pressure Vessel ......................................................................................................... 31

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LIST OF EXHIBITS Exhibit 1 Montecito Water District Service Boundary and Study Area Exhibit 2 Seawater Intake Site Alternatives Exhibit 3 Concentrate Discharge Site Alternatives Exhibit 4 Candidate Desalination Plant Sites Exhibit 5 Candidate Desalination Plant Sites Selected for Further Evaluation Exhibit 6 Conceptual Layout of Desalination Plant at Site P6 – District Yard Exhibit 7 Base Option System Alternative Exhibit 8 Option 1 System Alternative Exhibit 9 Option 2 System Alternative Exhibit 10 Option 3 System Alternative Exhibit 11 Variation of Base Option System Alternative

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I. INTRODUCTION A. INTRODUCTION AND BACKGROUND

The Montecito Water District (District) was formed as a County Water District in November 1921, in accordance with the California Water Code, with the purpose of furnishing potable water within the District’s service area. The District’s service area includes the unincorporated Montecito and Summerland communities, as well as Toro Canyon, and portions of the western Carpinteria Valley and the City of Santa Barbara as shown in Exhibit 1.

The District is located on the Central Coast of California, adjacent to the City of Santa Barbara in southern Santa Barbara County. The District extends 5½ miles to the east of the City of Santa Barbara and 3½ miles from the coast to the Santa Ynez coastal mountains. The District encompasses an area of approximately 9,225 acres of unincorporated lands. Geographically, the overall terrain varies in elevation from sea level to its highest elevation of about 1,820 feet against the coastal foothills.

During the 2013/14 Water Year (WY), which began on October 1, 2013, the District was projecting a supply shortage of approximately 1,300 acre feet (AF). This supply shortage prompted the District to adopt Ordinances 92 and 93, both of which restrict and limit customer water use with mandatory conservation measures1. Since implementing these mandatory conservation measures, the District has achieved a 45% reduction in customer usage when comparing customer use of March through September 2014 to the same period in 2013. In addition to mandatory conservation measures, the District also procured supplemental water supplies via the State Water Project and augmented its groundwater supply.

These actions prevented the projected water supply shortage from occurring, however the District is concerned about the 2014/15 WY as well as the 2015/16 WY due to the fact that the majority of its water supply is provided by surface water sources that are highly dependent upon precipitation for recharge. If significant precipitation and recharge does not occur during the 2014/15 WY, the District’s long range supply projected for the 2015/16 WY may only be one third of its theoretical long term available supply, requiring the District to further restrict and ration the available water supply.

With available local, regional and State surface water supplies significantly reduced by this on-going and historic drought, the District is evaluating the feasibility of incorporating desalinated ocean water into its water supply portfolio.

1 Montecito Water District Ordinance 92 Adopted by Board of Directors on February 11, 2014. Montecito Water District Ordinance 93 Adopted by Board of Directors on February 21, 2014.

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The District recognizes that desalinated ocean water may provide the District with a local, reliable, drought proof supply that could provide the District with water security during extended droughts and possibly during other supply interruptions due to physical system failures.

B. OBJECTIVES OF CONCEPTUAL FEASIBILITY STUDY

The District contracted with RBF Consulting, a Company of Michael Baker International, to perform a conceptual feasibility study to evaluate the overall feasibility of incorporating desalinated ocean seawater into the District’s water supply portfolio.

This conceptual feasibility study focuses on several key aspects of a desalinated water supply for the District, including the potential size and operation of the desalination plant, seawater intake alternatives, concentrate (brine) discharge alternatives, feedwater conveyance pipeline alternatives, brine conveyance pipeline alternatives and product water conveyance pipeline alternatives. This study also evaluates and discusses the anticipated regulatory and permitting requirements associated with this project, estimated costs for project implementation and a conceptual schedule for project implementation.

The conceptual feasibility study focuses on desalination as a new water supply, based on direction from the District and strong community support for desalination as expressed at the September 18, 2014 Montecito Water Summit luncheon. As part of a balanced water supply portfolio, the District will continue to pursue conservation, recycled water, local groundwater and imported water through ongoing efforts and studies such as a recommended update to the District’s Urban Water Management Plan.

II. DESALINATION PLANT CONCEPTUAL SIZING A. SUMMARY OF DISTRICT WATER SOURCES

The District has local, regional and imported water supplies available to meet customer demands, with the majority of these supplies consisting of surface water supplies as shown in Table 1 below. The District’s water supply portfolio has remained largely unchanged since the District was formed in November 1921, with the exception of the introduction of water supplied via the State Water Project (SWP).

The State Water Project (SWP) became a part of the District’s water supply in 1991 with deliveries beginning in earnest in 1998. The District’s full SWP entitlement is 3,000 acre-feet per year (AFY), which does not include a 300 AFY share of a drought buffer maintained by the Central Coast Water Authority for its project participants. The California Department of Water Resources (DWR) determines the percent of entitlement to be allocated to each water purveyor for each calendar year. Review of DWR entitlements from 1998 to 2013 indicates that the District has been provided with

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entitlement allocations ranging from 35% to 100%.2 In 2014, the DWR provided an entitlement allocation of only 5%, which equates to 165 AFY. The long term theoretical supply of this source per the District’s 2005 Urban Water Management Plan (UWMP) assumes a 76% entitlement allocation (of 3,000 AFY), which is equivalent to 2,280 AFY3.

Historically, the District has maximized the use of its less expensive local and regional water supplies and has not used all of its available State Water Project entitlement.

Per the District’s 2005 UWMP, the District has determined that it has a theoretical long term available water supply of 7,380 AFY as summarized in Table 1 below.

TABLE 1 – LONG TERM THEORETICAL AVAILABLE WATER SUPPLY Source of Supply Type Supply (AFY)

Lake Cachuma Regional Surface Water 2,906

Jameson Lake Local Surface Water 1,569

Doulton Tunnel Local Infiltration Water 375

Groundwater Local Groundwater 250

State Water Project Imported Surface Water 2,280

Total - 7,380

While Table 1 above provides the theoretical availability of the District’s water supplies, Table 2 below illustrates the actual water supplied to meet demands from 1998 to 2013. The primary difference between the theoretical supply and actual supply is the amount of State Water that has been used to meet demands.

TABLE 2 – ACTUAL AVERAGE DISTRICT WATER SUPPLY (1998 – 2013)

Source Average Annual Supply (AFY)

Percent of Total (%)

Jameson Lake 1,520 26%

Doulton Tunnel 362 6%

Groundwater Wells 227 4%

Lake Cachuma 2,958 51%

State Water Project 806 13%

Total 5,872 100% Source: District historical production records.

2 Per data provided by the Central Coast Water Authority (CCWA). 3 Mosby, Tom., 2005, Montecito Water District Urban Water Management Plan Update.

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The theoretical and actual supply figures shown in Tables 1 and 2 above indicate that local and regional supplies contribute on average 5,100 AFY of supply to meet demands with additional supply available from imported State Water.

B. SUMMARY OF DISTRICT WATER DEMANDS

The District currently has six distinct customer classifications as shown in Table 3 below.

TABLE 3 – DISTRICT CUSTOMER CLASSIFICATIONS Customer Classification Number of Accounts Sales (AFY)

Single Family Residential 4,131 4,205

Multi-Family Residential 47 139

Commercial 104 278

Institutional 72 431

Agriculture 37 587

Non-Potable 2 137

Total 4,393 5,777 Source: Per District sales figures for the 2013/14 fiscal year.

Per the information presented in Table 3, approximately 94% of the District’s customer accounts and 73% of the total water use is dedicated to serving Single Family Residential customers.

For the purposes of this report, water demand is taken to be the sum of customer sales and non-revenue (un-accounted) water,4 and is equal to production.

Review of historical District demand and local rainfall records indicates that demand is highly dependent upon local rainfall. As Table 4 illustrates, demand has ranged anywhere from a low of 3,839 AFY in 1998, which was a year with more than twice the average annual rainfall, to a high of 7,162 AFY in 2007 which was a year of only 49% of average rainfall.

4 Non-revenue (un-accounted) water is defined as water that has been produced and is “lost” before it reaches the customer. Losses can be real losses (through leaks, etc.) or apparent losses (metering inaccuracies).

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TABLE 4 – DISTRICT DEMAND AND AVERAGE RAINFALL (1998 – 2013) Year Annual District Water Demand (AFY) Percent of Average Rainfall1 1998 3,839 221% 1999 5,546 56% 2000 5,357 123% 2001 4,755 142% 2002 5,982 76% 2003 5,715 87% 2004 6,467 103% 2005 5,762 131% 2006 5,887 106% 2007 7,162 49% 2008 7,085 97% 2009 6,481 73% 2010 5,469 146% 2011 5,297 94% 2012 6,305 72% 2013 6,848 25%

Average 5,872 - Source: Per District rainfall records for 583 San Ysidro Road, Montecito CA. Average annual rainfall is approximately 20-inches.

In the fall of 2008, the District adopted a tiered rate structure.5 The tiered rate structure charges customers higher water rates as water use increases. Prior to the adoption of this rate structure, customers were charged a flat rate regardless of the amount of water used. Table 4 above demonstrates the reduction in demand affected by this rate structure change.

The 2005 UWMP included demand projections which examined full build-out of the District in the year 2030. The UWMP projected a demand of approximately 7,900 AFY at full build-out.

With the District adopting a tiered rate structure in 2008 and other water conservation measures anticipated to reduce demands, such as the State’s 20 by 2020 Water Conservation Plan, this study has assumed that the projected demand levels at full build-out will be reduced by approximately 20% to 6,300 AFY.

C. RELIABILITY OF EXISTING WATER SUPPLIES

All water supplies have vulnerabilities, and no supply can be 100% reliable under all conditions, whether this be related to climactic, physical system, environmental, regulatory or institutional factors.

5 Montecito Water District Board of Directors Adopted Resolution No. 2047 on August 20, 2008.

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The following provides an analysis and overview of the reliability of the District’s water supplies and how they may be impacted during a drought and also during an unscheduled emergency interruption in supply due to physical system failures.

1. Reliability of Supplies During Drought

Approximately 90% of the District’s water supply is provided by surface water sources which rely upon precipitation for recharge. During extended droughts, these surface water supplies are severely depleted and the District must rely upon customer conservation to offset the loss of these sources.

The following analysis was performed to determine the approximate supplemental supply required from a seawater reverse osmosis (SWRO) plant to sustain District demands at full build-out under drought conditions. As previously noted, the projected demand at full build-out has been reduced by 20% as shown in Table 5 below. The demand used in this analysis does not include possible increases in demands that may occur under extreme drought conditions.

TABLE 5 – PROJECTED DEMAND AT FULL BUILD-OUT Description AFY

Year 2030 Demand per 2005 UWMP 7,900

Customer Conservation of 20% -1,600

Year 2030 Demand w/ 20% Conservation 6,300

Table 6 below contains four drought scenarios which examine the range of supply shortfalls anticipated during drought conditions similar to those currently projected for the 2014/15 Water Year (WY). All four scenarios assume demand levels of 6,300 AFY, which represents demand at full build-out with 20% customer conservation. No externally banked, stored or supplemental water purchases are reflected in these scenarios.

Scenario A includes only local supplies which are similar to those projected for the 2014/15 WY. The local supplies consist of Lake Cachuma (1,193 AFY), Jameson Lake (375 AFY), Doulton Tunnel (80 AFY) and groundwater (425 AFY).

Scenario B includes the same local supplies and also includes a State Water Project supply of 800 AFY, which is equivalent to the District’s actual historical supply from this source.

Scenario C increases the supply from Jameson Lake from 375 AFY to 1,300 AFY with all other local supplies remaining at the 2014/15 WY projections. The supply from Jameson Lake is increased to reflect the potential modification to the operation of this reservoir if a desalinated supply were available. It is assumed that with a constant desalinated water supply available, supply from this reservoir would be minimized during normal years to

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allow the District to increase storage in this reservoir and thereby increase supply from this reservoir during drought periods.

Scenario D includes the same assumptions as Scenario C, and also includes a State Water Project supply of 800 AFY, which is equivalent to the District’s actual historical supply from this source.

TABLE 6 – PROJECTED SHORTFALLS DUE TO DROUGHT CONDITIONS

Description Scenario A

(AFY) Scenario B

(AFY) Scenario C

(AFY) Scenario D

(AFY)

Local Supplies 2,100 2,100 3,000 3,000

Year 2030 Demand w/ 20% Conservation 6,300 6,300 6,300 6,300

Estimated State Water Project Supply 0 800 0 800

Estimated Supply Shortfall -4,200 -3,400 -3,300 -2,500

As the above analysis indicates, supply shortfalls ranging from 2,500 AFY to 4,200 AFY are projected at build-out under drought conditions, depending on how local and imported supplies are managed.

These shortfalls could be met by desalination plant capacities of 2.5 million gallons per day (MGD) and 4.2 MGD respectively.

2. Reliability of Supplies Due to Other Interruptions

While drought conditions impact the availability of both local and imported surface water supplies, the District’s water supplies are also subject to other factors that may interrupt the supply. For example, the Tecolote Tunnel, which conveys State and Cachuma water from Cachuma Lake to the District could be completely interrupted for an extended duration due to a significant seismic event that damages storage or conveyance facilities. Lake Cachuma not only conveys the water impounded by Bradbury Dam but it also acts as the “pass-though” facility for all State Water Project deliveries.

The drought analysis above indicated that supply shortfalls ranging from 2,500 AFY up to 4,200 AFY could be met with desalination plant capacities ranging from 2.5 MGD to 4.2 MGD respectively. An analysis was performed to determine if a desalination plant capacity of 2.5 MGD could meet customer demands under an assumed six month interruption of the Tecolote Tunnel during a “normal” supply year at build-out conditions.

The following assumptions were used for this analysis:

Demand level of 6,300 AFY; Interruption in supply assumed to begin in May with service restored in November;

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Local supplies (Jameson Lake and groundwater) are maximized during supply interruption;

Desalinated supply exists in District’s water supply portfolio and is operating at 1.25 MGD before supply interruption and is increased to 2.5 MGD during interruption.

Results from this supply interruption analysis indicate that with a desalinated supply operating at 2.5 MGD, additional customer conservation ranging from 20% up to 30% would be required throughout the entire supply interruption period. Similarly, with a desalinated water supply operating at 4.2 MGD, additional customer conservation ranging from 0% up to 10% would be required throughout the supply interruption period.

If the District were to lose its other local supply sources of the Doulton Tunnel and/or Jameson Lake, a 2.5 MGD desalination plant would be capable of providing the average supply of these sources. It is important to note however that additional system improvements (i.e. pumping stations) would be required to serve customers at higher elevations typically served by these sources.

With approximately 95% of the District’s water supply impounded by dams and conveyed via tunnels, desalinated ocean water may provide the District with added “water security” by providing a local water supply in the event of a catastrophic system failure.

D. DESALINATION PLANT OPERATION

Based on the review of previous studies6, conditions surrounding the current drought, and the above analyses it appears that a seawater desalination plant with an initial capacity of 2.5 MGD (2,500 AFY at 90% utilization) would able to augment the District’s existing water supply portfolio to provide not only a drought proof supply, but would also increase the reliability of the District’s supply in the event one or more of the District’s sources were to become unavailable. The following discussion addresses how this desalination plant would be operated under normal conditions.

Table 7 below contains four operational scenarios which examine the range of supply shortfalls anticipated during “normal” supply conditions. All four scenarios assume demand levels of 6,300 AFY, which represents demand at full build-out with 20% customer conservation. No externally banked, stored or supplemental water purchases are reflected in these scenarios.

Scenario 1 includes only local supplies at 5,100 AFY as presented in the 2005 UWMP and summarized in Table 1 above. The local supplies consist of Lake Cachuma (2,906 AFY), Jameson Lake (1,569 AFY), Doulton Tunnel (375 AFY) and groundwater (250 AFY).

Scenario 2 includes the same local supplies and also includes a State Water Project supply of 800 AFY, which is equivalent to the District’s actual historical supply from this source based on records from 1998 to 2013. 6 Mosby, Tom., 2005, Montecito Water District Urban Water Management Plan Update. Bachman, Steven., Alroth, Jon., 2005, Montecito Water District Water Supply Optimization Plan.

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Scenario 3 reduces the supply from Jameson Lake by 1,000 AFY with all other local supplies remaining the same. The supply from Jameson Lake is decreased to reflect the potential modification to the operation of this reservoir if a desalinated supply were available. It is assumed that with a constant desalinated water supply available, supply from this reservoir would be minimized during normal years to allow the District to increase storage in this reservoir and thereby increase supply from this reservoir during drought periods.

Scenario 4 includes the same assumptions as Scenario 3, and also includes a State Water Project supply of 800 AFY, which is equivalent to the District’s actual historical supply from this source.

TABLE 7 – DESALINATION PLANT OPERATIONAL SCENARIOS Description Scenario 1 (AFY) Scenario 2 (AFY) Scenario 3 (AFY) Scenario 4 (AFY)

Local Supplies 5,100 5,100 4,100 4,100

Year 2030 Demand w/ 20% Conservation 6,300 6,300 6,300 6,300

Estimated State Water Project Supply 0 800 0 800

Estimated Supply Shortfall -1,200 -400 -2,200 -1,400

As the above analysis indicates, supply shortfalls ranging from 400 AFY to 2,200 AFY are projected at build-out under “normal” supply conditions, depending on how local and imported supplies are managed.

These shortfalls could be met by a 2.5 MGD desalination plant operating at 10% to 80% utilization.

E. DESALINATION PLANT CAPACITY

The above discussion suggests an initial desalination plant capacity of 2.5 MGD based on a planning period ending in the year 2030. However, to reduce initial capital costs, the District may elect to implement the desalination plant in multiple phases.

Prudent planning would consider the possibility of expanding the plant capacity at some future time, eventually reaching an ultimate capacity of 4.0 MGD or more.

The lowest capital cost option would be to construct the infrastructure for the desalination plant for only the initial capacity. However, if the District elects to increase the production capacity at a later date, portions of this buried infrastructure may be undersized and the District would then be required to design, permit and construct additional parallel infrastructure. In addition, the public roadways and other areas impacted by the initial project would be affected by additional construction activities.

For these reasons, this study is based on the assumption that, with the exception of the intake system, the initial infrastructure supporting the desalination plant will be sized for an ultimate plant capacity of 4.0 MGD.

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III. FEASIBILITY CONSIDERATIONS The feasibility of constructing and operating a desalination plant must consider much more than just the treatment process. Implementation of this type of project must consider the feasibility associated with intake of seawater (feedwater), conveyance the feedwater to the desalination plant, power supply to the desalination plant and feedwater pumping facilities, conveyance and discharge of the concentrate (brine) and conveyance of the product (treated) water to the distribution system. In addition there are financial, public acceptance, environmental, and regulatory considerations that must be evaluated.

This section provides a feasibility analysis for each major component of the desalination process including:

Seawater Intake, Brine Conveyance and Discharge, Desalination Plant, Power Supply, and Product Water Conveyance.

A. SEAWATER INTAKE

This section provides a conceptual feasibility assessment for seawater intake options that could supply feedwater from the Pacific Ocean to a proposed desalination facility. For a 2.5 MGD (approximately 1,700 gpm) plant, approximately 5.6 (approximately 3,900 gpm) MGD of seawater is required as feedwater assuming 45% recovery through the reverse osmosis (RO) process. For a 4.0 MGD ultimate plant (approximately 2,800 gpm) approximately 8.9 MGD is required (approximately 6,200 gpm).

Evaluation of feasible intake sites began with an analysis of the coastline within the study area using aerial imagery and Geographic Information System (GIS) data to identify potential sites within the study area located at a distance no more than 1,000 feet from the shoreline. This distance was selected as intake systems may become cost prohibitive to construct at distances beyond this threshold.

With the boundary condition established, the coastline was canvassed using the aerial imagery to identify candidate intake locations. Considerations for candidate sites included existing land use, proximity to the coastline, topography, and constructability.

Following this “paper” analysis, three separate field inspections were conducted to more closely analyze each potential intake location. The first field inspection was used to determine which potential intake locations identified during the paper analysis were feasible. The subsequent field inspections were conducted with industry intake and construction experts to validate candidate intake

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locations. As a result, five intake locations are considered in this study. These locations are described below and shown in Exhibit 2.

Intake Site 1 (I1): Eastern side of Santa Barbara Cemetery property near Channel Drive; Intake Site 2 (I2): South of Jameson Lane and west of Posilipo Lane, on the former Miramar

Hotel property; Intake Site 3 (I3): On private property on Fernald Point Lane directly adjacent to Picay

Creek; Intake Site 4 (I4): On private property near the intersection of North Jameson Lane and the

Sheffield Road Highway 101 northbound off-ramp; Intake Site 5 (I5): Lookout Park in Summerland, south of Highway 101 and east of Evans

Avenue.

1. Open-Ocean vs Sub-Surface Intakes

Eight seawater intake options were considered in this study consisting of one open-ocean intake and seven subsurface intake options. Implementation of an open-ocean intake in light of the proposed modifications to the California Ocean Plan will be difficult and can only be pursued if it is demonstrated that implementation of a sub-surface intake is not “feasible”.

A subsurface intake is defined by any intake that extracts water from water bearing formations near or under the seafloor. The principal advantage of sub-surface intakes cited by regulators and environmental groups is the avoidance of impingement and entrainment of marine life (fish larvae and eggs). Additionally, subsurface intakes reduce or eliminate many pretreatment issues regarding feedwater quality associated with screened open-ocean intakes due to the filtering action of the subsurface material. The following discussion describes the geologic and hydrogeologic characteristics of the near-shore environment within the study area, which are critical to the assessment of sub-surface intakes.

2. Geology and Hydrogeology

For a sub-surface intake system to perform satisfactorily, favorable near-shore geologic conditions must be present such as adequate deposits or layers of alluvium material, which generally consist of silt, sand and gravels.

A preliminary geologic investigation was performed as a part of this study to determine if the near-shore geology within the study area is suitable for a sub-surface intake system. Mr. Adam Simmons, a local certified Engineering Geologist and Hydrogeologist, examined the near-shore geology of five potential intake locations. The locations spanned from the western edge of the District Boundary near the Santa Barbara Cemetery to the eastern edge near Summerland. The preliminary geologic investigation did not include any physical sampling or testing and was based solely on inferred geologic conditions. Per the

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preliminary investigation, the offshore geology varies significantly along the five miles of coastline.

The following summarizes the findings of the preliminary geologic investigation report. The full report is attached as Appendix A.

Intake Area 1 – Santa Barbara Cemetery Area

This intake location is generally located near the eastern edge of the Santa Barbara Cemetery adjacent to Channel Drive. The on-shore land mass is situated on a coastal bluff that protrudes approximately 60-feet above sea level with sheer cliffs.

The inferred near-shore geology indicates the presence of an anticlinal fold with very little alluvium deposits present. However, this area is underlain by the relatively permeable Casitas formation to a depth of approximately 200 feet. The Casitas formation is a primary groundwater source in the study area.

Intake Area 2 – Miramar Area

This intake location is generally located near the former Miramar Hotel site, south of Jameson Lane and west of Posilipo Lane. The on-shore land mass is approximately 20-feet above sea level.

The inferred near-shore geology indicates the presence of older alluvium deposits approximately 100-feet to 200-feet thick below the seabed. These older alluvium deposits are underlain by the Casitas formation and the moderately permeable Santa Barbara formation to depths of approximately 1,000 feet or more.

Intake Area 3 – Fernald Point Area

This intake location is generally located near the eastern end of Fernald Point Lane near the Picay Creek outfall to the Pacific Ocean. The on-shore land mass is approximately 15-feet above sea level.

The inferred near-shore geology indicates the presence of older alluvium deposits approximately 50-feet to 100-feet thick below the seabed. It is underlain by depths of the Casitas and Santa Barbara formations similar as Intake Area 2.

Intake Area 4 – Sheffield Drive Off-Ramp Area

This intake location is generally located near the intersection of North Jameson Lane and the Sheffield Road Highway 101 northbound off-ramp. The on-shore land mass is approximately 85-feet above sea level.

The Fernald Point fault runs at an angle to the shoreline and would be encountered approximately 250 feet from the shoreline. The inferred offshore geology indicates the

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presence of older alluvium deposits approximately 25-feet to 50-feet thick below the seabed. Landward of the fault, the older alluvium is underlain by approximately 300 feet of the Casitas formation. On the ocean side of the fault, the older alluvium is underlain by only approximately 100 feet of the Casitas formation and the Casitas formation in this area is underlain by the poorly permeable Pico formation.

Intake Area 5 – Summerland Area

This intake location is generally located near Lookout Park in Summerland, which is just south of Highway 101 and east of Evans Avenue. The on-shore land mass is situated on a coastal bluff that protrudes approximately 60-feet above sea level with sheer cliffs.

The inferred near-shore geology indicates the presence of the permeable Casitas formation near the surface with very little alluvium present. The area also has several historic oil wells located both on and off-shore, which raises concerns regarding liability and water quality associated with potential existing or future petroleum-impacted groundwater.

3. Intake Types

The following section describes the seven types of sub-surface intakes as well as the open-ocean intake system with the associated advantages and disadvantages of each technology as it applies to this study.

Vertical Wells

Description

Conventional vertical wells are commonly used for the extraction of groundwater and have been used to source small seawater desalination plants (less than 1 MGD). Non-corrosive materials would be required for all down-hole equipment. The geology appears to be suitable for this alternative at Intake Sites I1, I2, I3 and I4.

Advantages Proven technology, well understood, numerous providers; Avoids marine life impingement and entrainment; Unit cost for construction is relatively low.

Disadvantages Limited capacity (approximately 300 gpm) per well which would require

approximately ten to twenty individual wells spaced hundreds of feet apart on multiple sites along the coast to meet feedwater quantity requirements;

Substantial temporary and permanent impacts along the Montecito coast due to multiple well sites;

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Potential for exposure to coastal hazards and bluff erosion; Potential temporary and permanent impacts to coastal views and coastal access due to

multiple well sites; Potential impacts on local groundwater resources and existing wells (will require

groundwater modeling to determine); Potential to induce seawater intrusion on the ocean side of the wells.

Feasibility Assessment

It is not considered feasible to pursue this intake type due to the relatively large number of sites required and distributed along approximately 12,000 feet of coastline. In addition, groundwater modeling requirements, unknown groundwater impact mitigation requirements, extensive site acquisition and associated costs and disruption related to the intake system make this intake type cost prohibitive.

It is unlikely that vertical wells would be capable of providing the required feed water capacity. If vertical wells were capable of providing the required feed water capacity, they would most likely be located on the beach to avoid creating interference with existing groundwater wells in the coastal area. If located on the beach, this type of intake system would require the wellhead to be constructed on the beach which is not considered feasible due to environmental and regulatory requirements. In particular, future coastal erosion may preclude this intake technology from being viable.

Pumping from coastal wells could potentially cause a negative impact on nearby fresh groundwater aquifers. Recently, traditional on-shore groundwater wells in confined coastal aquifers have increased in quantity in response to the drought. As the freshwater aquifer is depleted without being recharged through natural processes, salt water intrusion from the ocean can occur. Desalination has often been cited as a way to reduce saltwater intrusion by producing potable water without disturbing freshwater aquifers. However, depending on the local groundwater profile, beach wells to supply the desalination plant could exacerbate intrusion problems.

Not withstanding the above concerns, capacity limitations, and regulatory difficulty, should the District desire to pursue beach wells further, a site-specific hydrogeological survey and groundwater modeling effort would be required in order to more accurately define potential on-shore groundwater impacts and beach well performance capabilities.

Slant Wells

Description

Slant wells are typically drilled from the beach at an angle and extend beyond the shoreline under the seabed to tap the saline aquifer under the ocean. A slant well, as illustrated in

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Figure 1, is drilled at a shallow angle from the horizontal (typically 15 – 25 degrees). Drilling lengths of up to 1,000 feet have been proposed in other projects. The water is typically extracted from the well with a submersible pump. All down-hole materials including the pump are typically constructed of Super-Duplex corrosion resistant materials. This technology has been demonstrated for seawater intake by the Municipal Water District of Orange County (MWDOC) at Doheny Beach in Dana Point, CA and has been proposed for California American Water’s Monterey Peninsula Water Supply Project. The geology appears to be suitable for this alternative at Intake sites I1, I2, I3 and I4.

Advantages Angled construction increases screen length in the targeted area and thereby

increasing production for the well and reducing the number of wells required; Multiple wells (two to four) can be drilled from a single site; Drawdown is considerably less than vertical wells thereby reducing impact on local

groundwater resources; Angled construction allows placement of a portion of the well screen below the ocean

floor thereby taking advantage of vertical infiltration and permeability.

Disadvantages Unit cost for construction is relatively high; Requires marine permitting (State Lands Commission); Potential impacts on local groundwater resources and existing wells (requires

groundwater modeling to determine); Only one pilot plant for this technology as an intake for seawater desalination (no

full-scale examples); Wellhead and casing could be potentially impacted by coastal erosion; May induce seawater intrusion on the ocean side of the wells; Capacity of each slant well is unknown, thereby requiring “prototype” testing to

determine total number of slant wells required to meet feedwater requirements.

Feasibility Assessment

Many of the proposed seawater desalination projects in California have explored the feasibility of this alternative, and suitable geology appears to be available in the study to area to consider this alternative further. While it may be feasible to site two or three slant well clusters that would have sufficient capacity for this project, significant implementation time is required to allow for testing, permitting, and groundwater modeling, and this type of an intake would likely impact local groundwater resources.

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FIGURE 1: SLANT WELL INTAKE PROFILE

Deep Infiltration Gallery (DIG)

A deep infiltration gallery (DIG) concept has been developed by the San Diego County Water Authority as a sub-surface intake alternative for a large (150 MGD) desalination project proposed to be located on Camp Pendleton. This intake concept involves a large diameter deep tunnel underneath the ocean floor through which vertical wells are drilled. Water enters the deep tunnel via the wells by gravity and is pumped from the tunnel by an on-shore pump station.

This type of an intake is not considered feasible for desalination plants less than 50 MGD capacity due to the length and diameter of the sub-seafloor tunnel that would be required, as well as the associated cost, construction time, and lack of existing examples.

Horizontal Collector Wells

Description

Horizontal collector wells are currently provided under the trade name “Ranney Wells” by Layne Christensen. These wells are generally comprised of a single large vertical reinforced concrete shaft with horizontal lateral well screens projected radially out into the aquifer to collect and filter the water. Figure 2 below contains a general illustration of this intake system. These intakes have been used extensively for fresh water intakes along rivers and have been installed in a few (less than 10) installations for seawater intake.

This type of intake structure would normally require a collector structure located on the beach with the pumps mounted in the collector structure. The beach structure would then be connected with a second deep remote structure via a gravity tunnel, and the seawater would be pumped from the remote structure. The geology and on-shore topography appears to be suitable for this alternative at Intake sites I2 and I3 only. However, similar to vertical wells, Ranney Wells are not considered feasible due to coastal erosion concerns associated with beachfront structures, in addition to environmental, aesthetic, and regulatory issues.

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Advantages Minimal impact on local groundwater resources; Proven constructability and track record; Would allow for use of less expensive vertical turbine pumps which are more

efficient and easier to maintain than submersibles; One intake facility can potentially provide required capacity.

Disadvantages Sole source provider (non-competitive); Will require substantial permitting effort to site a structure on the beach, with

considerable time, cost, and uncertainty; Difficult beach construction; Longer construction duration; Vulnerability to coastal erosion; Additional coastal issues such as visual impact and beachfront temporary and

permanent easements.

Feasibility Assessment

Due to the requirement to permit and construct a significant structure on the beach, this alternative is not considered feasible.

FIGURE 2: HORIZONTAL COLLECTOR WELL

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Excavated Seabed Infiltration Gallery (ESIG)

Description

An excavated seabed infiltration gallery (ESIG) is an off-shore shallow pipe gallery installed underneath the seabed. There is one example of this technology in operation serving a seawater desalination plant in Fukuoka, Japan (see Figure 3). The intake typically consists of an array of horizontal collector drain pipes, installed 6 to 10-feet below the ocean floor, which are manifolded and connected to a single pipe that conveys the seawater to the shoreline. The seafloor must be excavated with engineered fill placed over the collector pipes. Water enters the collector system by gravity induced by an on-shore pump station. For the 2.5 MGD desalination project, the gallery would occupy approximately 5 acres of seafloor. Because the feasibility of this alternative is relatively independent of geology, this alternative could be considered at all five intake sites.

Advantages Can be applied to almost any geologic condition; No impact on inland groundwater resources.

Disadvantages Although these systems can be constructed in calm embayments, they are difficult to

construct on the open ocean where significant wave action impedes construction and also affects seafloor stability. In this case, a water depth of 30 feet or more would be required which is approximately 1,000-feet off-shore, and construction would have to contend with have heights of 10 feet or more;

Excavation of seafloor will potentially disrupt benthic communities and degrade ocean water quality;

Unknown long-term performance of these systems relative to fouling and stability of engineered fill, with no ability to maintain or clean the system;

Significant construction duration including use of temporary piers, and associated impacts to coastal views and marine life;

This technology would require extensive regulatory permitting and likely be controversial due to marine and coastal impacts.

Feasibility Assessment This technology represents an extraordinary cost, marine impact, coastal impact and long-term uncertainty and is not considered appropriate or feasible for a relatively small community-scale desalination facility such as Montecito.

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FIGURE 3: EXCAVATED SEABED INFILTRATION GALLERY (FUKUOKA, JAPAN)

Sub-Seafloor Drains (Neodren)

Description

A sub-seafloor drain is a flexible permeable pipe installed 10-feet to 20-feet beneath the seafloor using horizontal directional drilling (HDD) technology. Figure 4 contains an illustration of this intake type. The permeable pipe is manufactured using high density polyethylene (HDPE) and can be manufactured to tightly controlled porosities. This permeable pipe has the distinct advantage of being installed directly within the existing native geology without the need for installing gravel packing or other engineered materials around the pipe. Seawater enters the permeable pipe by gravity induced by an on-shore pump. Currently, this technology (trade name Neodren) is a patented technology held by Catalana de Perforacions, located in Spain. While this intake system is currently in use for several seawater desalination intakes in Spain, this technology has not been deployed in the United States. However, it is now available through a California-based company7.

For the 2.5 MGD plant considered in this study, the intake system would conceptually consist of up to four individual drains installed in a fan arrangement emanating from a single site with the permeable sections of the intake drains extending approximately 1,000-ft beyond the shoreline. The geology appears to be suitable for this alternative at Intake sites I1, I2, I3 and I4.

7 IntakeWorks located in Sacramento, CA.

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Advantages No impact to local groundwater resources; Minimal impact to the seafloor; Construction can be performed in a relatively small area at both land and ocean ends

of the drains; Drain can be launched from well outside any coastal erosion zone; Drain can operate in relatively thin alluvial beds, and lends itself to various

contingency options; Installation technology (HDD) is a well-demonstrated and proven technology; Installation technology (HDD) could be used to install a new concentrate (brine)

outfall at the same site, thereby eliminating the need to acquire separate property or easements for intake and outfall sites and potentially decreasing overall project costs;

Due to the ability to specify and control permeable pipe porosity, this alternative probably produces a more superior and consistent water quality of all the sub-surface intake alternatives.

Disadvantages Sole source provider (non-competitive); No track record for this technology as intake for existing seawater desalination plants

in the United States; Capacity of sub-seafloor drain is unknown until first drain is installed, thereby

requiring “prototype” testing to determine total number of drains required to meet feedwater requirements;

Extensive seafloor exploration program is required to confirm feasibility of HDD, depth of alluvium and seafloor stability.

Feasibility Assessment

Along with the slant well alternative, the sub-seafloor drain (Neodren) alternative is considered to be a potentially feasible sub-surface intake alternative for this project. However, similar to the slant well alternative, a prototype test facility should be constructed to verify design criteria for a full scale installation.

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FIGURE 4: NEODREN SUB-SEAFLOOR DRAIN

Beach Infiltration Gallery

Description

A beach infiltration gallery consists of permeable pipe or screened pipe buried underneath the beach parallel to the shoreline, similar to the demonstration project constructed by the Long Beach Water Department. Buried collector structures would be required on the beach, connected to one or more remote pump structures via tunnels similar to the horizontal collector well alternative previously described. This infiltration gallery would likely traverse several thousand feet of shoreline.

This type of an intake is not considered feasible due to the significant disruption to the beach during construction as well as the potential for coastal erosion impacts to both the pipe gallery and collector structures on an exposed coastline.

Screened Open-Ocean Intake

As previously discussed, a screened open-ocean intake would only be considered if none of the sub-surface intakes previously described are feasible.

A screened open-ocean intake is an offshore intake that would typically include cylindrical wedge-wire mesh screens mounted on the ocean floor. Wedge-wire screens consist of a large wire wrapped cylinder mounted on pedestals at the end of an intake pipe below the water surface at water depths from 35 feet to 90 feet. The wires that are wrapped around the circumference of the cylinder have a triangular or wedge shaped cross-section. This technology has been demonstrated by the City of Santa Cruz, Marin Municipal Water District, and West Basin Municipal Water District. An example of a wedge-wire screen is shown in Figure 5 below.

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FIGURE 5: OPEN-OCEAN INTAKE WITH WEDGE-WIRE SCREEN

The primary feasibility issue for implementing open-ocean wedge-wire screens in California is potential impingement and entrainment of marine life. Other feasibility issues include potential impaired water quality due to the ingestion of sediment or algal blooms, required periodic cleaning of the wedge-wire screens to remove marine growth that tends to accumulate on the screens and reduces intake capacity, and ensuring proper structural design and metal alloys to withstand coastal wave and corrosion processes.

Again, since subsurface intakes appear to be feasible and are strongly preferred by regulatory agencies, a screened open-ocean intake is not under consideration for this project.

4. Intake Site Alternatives

As previously stated, sub-surface intake technology is the preferred alternative for this feasibility study. While there are many sub-surface intake technologies available, at this time it is assumed that only two intake systems may be viable for this project. The two intake types considered feasible at this conceptual level include the Neodren sub-seafloor drains (at Intake locations I1, I2, I3 and I4) and slant wells. Slant wells will only be considered at Intake location I1 because the impact to local groundwater resources would likely be substantially reduced at this location. Input from industry experts in the fields of slant wells, Horizontal Directional Drilling (HDD) and the Neodren sub-seafloor drain intake system was used to verify that these technologies are appropriate for further study at these intake locations.

For the HDD sub-seafloor drain alternative, a section of non-permeable pipeline would extend from the drilling site to the shoreline. A permeable section of the pipeline would extend from the shoreline beneath the seafloor. At this time it is assumed that a total of four sub-seafloor drains (intakes) will be installed to supply the initial plant capacity of 2.5 MGD.

Table 8 contains a summary of the approximate lengths of both the non-permeable and permeable sections for the HDD sub-seafloor drain at each intake site. As indicated in Table 8, the intake lengths could range from just under 5,000 feet to over 7,000 feet. This difference in length is directly related to the distance of the non-permeable section of

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pipeline. When the drilling site is located further from the shoreline, additional non-permeable pipe is required.

TABLE 8 – SUB-SEAFLOOR INTAKE ALTERNATIVES & CORRESPONDING LENGTHS

Intake Site

Non Permeable

Intake Length (ft)

Permeable Intake

Length (ft)

Number of

Intakes (Ea)

Total Intake Length

(ft)

I1 400 1,000 4 5,600

I2 350 1,000 4 5,400

I3 225 1,000 4 4,900

I4 800 1,000 4 7,200

I5 400 1,000 4 5,600

Table 9 below provides preliminary sizing information for a slant well system at Intake Site I1.

TABLE 9 – SLANT WELLS AT INTAKE LOCATION I1

Intake Site

Number of Wells

Angle of Well (deg)

Total Length per

Well (ft)

Screen Length

per Well (ft)

Number of

Clusters

I1 6 20-25 800 600 2

Intake Site I1 – Santa Barbara Cemetery

Intake Site I1 is generally located on the eastern side of the Santa Barbara Cemetery property near Channel Drive. Both the HDD sub-seafloor drain and slant well alternatives are considered at this location. Listed below are the advantages and disadvantages of using this site for an intake location.

Advantages for this location include:

Previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Adequate space for drilling equipment; Surrounding land use is institutional with limited residential; Relatively close to the shoreline which maximizes length of intake underneath the

ocean floor; Ease of access for both construction and future operation and maintenance;

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Relatively close to a convenient crossing beneath the railroad and US 101 for feedwater conveyance pipeline.

Disadvantages for this location include:

Property is not owned by the District; Site elevation (60 feet) will result in increased length of submersible pump equipment

(drop pipe, power cable, etc.); Uncertainties regarding potential future bluff erosion impacts to on-shore pipe or well

casing segments.

Intake Site I2 - Miramar

Intake Site I2 is generally located on the property of the former Miramar Hotel site, south of Jameson Lane and west of Posilipo Lane. This property is currently proposed as a new resort property and the proposed intake location would be in an area designated for surface parking. Listed below are the advantages and disadvantages of using this site for an intake location for the HDD sub-seafloor drain alternative.

Advantages for this location include:

Previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Adequate space for drilling equipment; Ease of access for both construction and future operation and maintenance; Relatively close to the shoreline which maximizes length of intake underneath the

ocean floor; Existing elevated railroad berm may provide a barrier to protect facilities from

potential future coastal erosion; Centrally located relative to potential desalination plant sites.

Disadvantages for this location include:

Property is not owned by the District; Intake will cross beneath railroad tracks; Site is potentially within floodway and/or coastal erosion zone; Feedwater pipeline will cross beneath US 101.

Intake Site I3 – Fernald Point

Intake Site I3 is generally located on private property near the eastern end of Fernald Point Lane near the Picay Creek outfall to the Pacific Ocean. The intake would be drilled from an

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existing private lot. Listed below are the advantages and disadvantages of using this site for an intake location for the HDD sub-seafloor drain alternative.

Advantages for this location include:

Previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Relatively close to the shoreline which maximizes length of intake underneath the ocean floor;

Disadvantages for this location include:

Property is not owned by the District; Surrounding properties are predominantly residential; Access would be via private driveway/property which will be difficult for

construction and future maintenance; Site is potentially within floodway and/or coastal erosion zone.

Intake Site I4 – Sheffield Drive Off-Ramp

Intake Site I4 is located near the intersection of North Jameson Lane and the Sheffield Drive US 101 northbound off-ramp. The site would be on previously disturbed private property and a portion of un-disturbed County property. Listed below are the advantages and disadvantages of using this site for an intake location for the HDD sub-seafloor drain alternative.

Advantages for this location include:

Portions of the site are previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Ease of access for both construction and future operation and maintenance; Adequate space for drilling equipment.

Disadvantages for this location include:

Relatively long distance to shoreline which reduces length of intake beneath ocean floor;

Site elevation (85 feet) will result in increased length of submersible pump equipment (drop pipe, power cable, etc.);

Property is not owned by the District; Surrounding properties are predominantly residential; Intake will cross beneath US 101 including bridge piers and the Union Pacific Rail

Road tracks.

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Intake Site I5 – Lookout Park (Summerland)

Intake Site I5 is located at Lookout Park in Summerland, which is just south of US 101 and east of Evans Avenue. Listed below are the advantages and disadvantages of using this site for an intake location for the HDD sub-seafloor drain alternative.

Advantages for this location include:

Previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Relatively close to the shoreline which maximizes length of intake underneath the ocean floor.

Disadvantages for this location include:

Limited space for drilling equipment may require special measures to achieve safe depth below toe of slope;

Site elevation (60 feet) will result in increased length of submersible pump equipment (drop pipe, power cable, etc.);

Uncertainties regarding potential future bluff erosion impacts to on-shore pipe or well casing segments;

Property is not owned by the District; Property is public park which would require closure during construction.

B. CONCENTRATE DISCHARGE AND DISPOSAL

This section provides a conceptual feasibility assessment for discharge of reverse osmosis process concentrate (brine) from the proposed desalination facility. Brine is typically discharged to the ocean using either an existing outfall from a wastewater treatment plant or a new dedicated ocean outfall. In either case, an engineered diffuser will be required at the end of the outfall to meet new discharge requirements in the proposed California Ocean Plan Amendments. These modifications are expected to require diffusion of the brine to the extent that the discharge does not increase salinity in the ocean more than 5 percent above ambient conditions measured 100 meters from the discharge (the regulatory zone of initial dilution (ZID)). For a 2.5 MGD desalination plant (approximately 1,700 gpm), approximately 3.1 MGD of brine (approximately 2,200 gpm) would be produced, at a salinity concentration of 60,000 mg/L8 to 65,000 mg/L assuming 45% recovery through the RO process (seawater concentration is approximately 34,000 mg/L at this location). For a 4.0 MGD ultimate plant (approximately 2,800 gpm) approximately 4.9 MGD of concentrate is produced (approximately 3,400 gpm).

8 1,000 Milligrams per Liter (mg/L) = 1 Part Per Thousand (ppt).

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1. Concentrate Discharge Types

The following section describes the off-shore portion (outfall) of the concentrate conveyance system. For this feasibility study two alternatives for concentrate discharge were considered; use of the existing Montecito Sanitary District (MSD) treated wastewater outfall and a new dedicated outfall.

The primary advantage of combining treated wastewater and brine in a single discharge are two-fold. First, in comparison to discharging pure brine, the reduced salinity of the combined flows allows for more rapid diffusion of the plume to meet salinity concentration limitations at the edge of the ZID. Secondly, in comparison to discharging only treated wastewater, the elevated salinity of the combined flows suppresses surfacing of the effluent plume. The other advantage is the potential reduction of project capital and operation and maintenance costs due to the elimination of a new ocean outfall/diffuser.

The principal disadvantage of using the MSD existing ocean outfall is the possible temporary shut-down of the desalination plant that would be required to provide MSD with full access to the outfall capacity. While additional capacity analysis of the existing outfall is needed to fully evaluate the potential impacts to MSD’s discharge capabilities, it is likely that operational guidelines would need to be developed to ensure the desalination plant brine discharge would not compromise MSD’s outfall capacity needs in any way. Another consideration is that the outfall would have to be re-permitted for use by both MSD and the District to allow the outfall to discharge desalination concentrate.

New Dedicated Concentrate Outfall

The second alternative for concentrate discharge and disposal would be through the use of a new dedicated outfall. It is assumed that during the construction of the sub-surface intake system, which may be constructed using HDD technology, a new dedicated concentrate discharge outfall could be constructed simultaneously.

The outfall would be constructed of high-density polyethylene (HDPE) pipe extending approximately 1,500-ft into the Pacific Ocean. An engineered diffuser system would be constructed at the end of the outfall to promote dilution of the concentrate in the Pacific Ocean, consistent with the proposed California Ocean Plan Amendments.

There are many advantages to this alternative including: intake and discharge facilities could be located in one area; realization of economy of scale for construction of both intake and discharge facilities simultaneously; no capacity limitations; and complete control and ownership of the outfall.

The primary disadvantage of this alternative, other than cost, is the permitting of a new ocean outfall which involves permitting with the Coastal Commission, State Lands Commission,

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Regional Water Quality Control Board, U.S. Army Corps of Engineers, and other local and state coastal permitting agencies.

2. Oceanographic and Biological Considerations

Siting of a new off-shore outfall should take into account oceanographic characteristics which include but are not limited to ocean depth, wave characteristics, ocean currents and seafloor composition. Overall success of an offshore outfall design includes the strategic placement of the discharge diffuser to avoid sensitive biological communities. Another emerging issue is turbulence mortality, which refers to potential adverse effects on fish larvae caused by the velocity of the discharge as it exits the diffuser. Careful design of the diffuser will be required to minimize turbulence mortality. Off-shore studies and evaluations to determine design criteria for the outfall diffuser system include current and wave measurements for extended durations, hydrodynamic modeling of the discharge plume, and icthyoplankton9 and benthic surveys.

3. Discharge Alternatives

In order to develop alternative locations for brine discharge, one alternative would be to construct a dedicated ocean outfall at the same location as the seawater intake (site-specific ocean modeling would be required for intake and discharge siting, both to avoid sensitive benthic resources and to ensure adequate separation between the source water intake and concentrate discharge). This would provide many advantages including easement or property procurement for only one area, disruption to only one site for intake and concentrate facility construction, possible economy of scale when constructing both intake and outfall using one HDD contractor, and location of all intake and discharge facilities in one area for ease of inspection and future maintenance.

The second type of alternative would be to use the existing MSD treated wastewater outfall. Therefore, for each alternative configuration of facilities, two alternative discharge locations have been considered: (1) placing the concentrate discharge location at the same location as the intake; and (2) using the existing MSD treated wastewater outfall.

The six concentrate (brine) discharge locations identified in this study are as follows and as shown in Exhibit 3.

Discharge Site 1 (D1): Eastern side of Santa Barbara Cemetery property near Channel Drive;

Discharge Site 2 (D2): South of Jameson Lane and west of Posilipo Lane, on the former Miramar Hotel property;

9 Icthyoplankton are the eggs and larvae of fish and are typically found in the sunlit zone of the water column, less than 200 meters deep.

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Discharge Site 3 (D3): On private property on Fernald Point Lane directly adjacent to Picay Creek;

Discharge Site 4 (D4): On private property near the intersection of North Jameson Lane and the Sheffield Drive US 101 northbound off-ramp;

Discharge Site 5 (D5): Lookout Park in Summerland, south of US 101 and east of Evans Avenue.;

Discharge Site 6 (D6): Montecito Sanitary District existing treated wastewater outfall.

For the new ocean outfall alternatives, the analysis assumed that HDD-deployed HDPE pipe would be installed with an engineered diffuser at the end.

For the alternative that considers connecting to MSD’s existing treated wastewater outfall, it is assumed that the existing outfall will not be extended further into the Pacific Ocean. Modifications to the diffuser system at the end of this existing outfall may be required based on further studies.

Table 10 contains a summary of the approximate length of each concentrate discharge outfall. As indicated in Table 10, the outfall lengths could range from approximately 1,700 feet to 2,300 feet. This difference in length is directly related to the distance of the drilling site from the shoreline (when the drilling site is located further from the shoreline, more discharge pipe is required).

TABLE 10 – CONCENTRATE DISCHARGE OUTFALL ALTERNATIVES & CORRESPONDING LENGTHS

Concentrate Discharge Site

On-Shore Outfall Section

(ft)

Off-Shore Outfall Length

(ft)

Total Length

(ft)

D1 400 1,500 1,900

D2 350 1,500 1,850

D3 225 1,500 1,725

D4 800 1,500 2,300

D5 400 1,500 1,900

D6 N/A N/A N/A

The site advantages and disadvantages for Concentrate Discharge sites D1 through D5 are the same as previously described for the Intake Sites I1 through I5, respectively with the exception that references to down-hole pump and well equipment are not applicable. It is unknown at this time if the off-shore diffusion and mixing characteristics at each of the discharge locations are significantly different.

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Concentrate Discharge Site D6 (MSD Existing Outfall)

Other than the advantages previously discussed, utilizing the MSD existing treated wastewater outfall would minimize marine construction costs. The MSD wastewater treatment facility is located on the western edge of the District service boundary near the intersection of Channel Drive and Monte Cristo Lane. The MSD has an existing ocean outfall with an inside diameter of 18-inches that extends approximately 1,500 feet into the Pacific Ocean to a depth of approximately 35 feet below sea level. The outfall is constructed of cast iron and was installed in 1961. An engineered diffuser section is located along the last 100 feet of the outfall. The engineered diffuser section consists of ten diffusers fitted with duck-bill check valves which are alternately oriented on the east and west side of the pipe.

C. DESALINATION PLANT

The following section discusses the overall process of desalinating ocean seawater.

1. Overview of Desalination Process

Seawater Reverse Osmosis (SWRO) is a process that desalinates water by pushing raw seawater under pressure through a semi-permeable membrane. This process requires the application of energy (pressure) to the more saline solution. A reverse osmosis membrane allows the passage of water molecules through the semi-permeable membrane, but excludes dissolved salts, organics, and bacteria. The water that is allowed to pass through the membrane is referred to as permeate or product water. The water that contains the high concentration of dissolved salts and organics is referred to as concentrate or brine. Figure 6 below provides a generalized schematic of the SWRO process.

FIGURE 6: SWRO MEMBRANE PROCESS

The membranes consist of six or seven spirally wound elements contained within pressure vessels, and the vessels would be arranged in “arrays” of twenty to fifty vessels each. Figures 7 and 8 below illustrate a typical membrane element and pressure vessel.

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FIGURE 7: RO SPIRAL WOUND MEMBRANE ELEMENT

FIGURE 8: MEMBRANE PRESSURE VESSEL

In addition to the SWRO membranes, other facilities located at a SWRO plant site include: pretreatment equipment, pumps, chemical handling, storage facilities, and non-process buildings and facilities. After passing through the SWRO process, the desalted water is void of essential minerals and is so pure that it is highly corrosive. Post-treatment, or re-mineralization, is required to protect downstream piping systems and to make the product water compatible with other District water supplies.

The District’s proposed SWRO facility would desalinate raw seawater obtained from a subsurface intake. It is assumed that pre-treatment consisting of granular media filtration (sand filters) with chlorination would be deployed in the event that the feedwater contains dissolved iron and manganese. This pre-treatment process would remove the iron and manganese and prevent the fouling of the downstream SWRO membranes caused by iron and manganese precipitation. If a subsurface intake is not feasible, substantially more pre-treatment will be required to remove suspended solids in the feedwater.

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After pretreatment, the filtered water (filtrate) would be pumped through SWRO membranes. A portion of the permeate will then be re-treated through membranes in what is referred to as a “second pass”. The second pass permeate is then blended with the first pass permeate to meet specific water quality goals for boron, bromide, sodium and chloride based on the fact that a significant portion of the water could be used for agricultural and landscape irrigation. For purposes of this study, a second pass percentage of 50% has been assumed.

An energy recovery system would be used to recover energy from the concentrate stream prior to its disposal to assist in reducing energy costs. After the SWRO process, desalinated water (permeate) would go through post-treatment to stabilize the water to prevent corrosion of the distribution system pipelines and consumer plumbing. The post-treatment process would most likely consist of:

Carbon dioxide; Lime (calcite beds); Sodium hydroxide (pH adjustment); and Sodium hypochlorite (disinfection - chlorine residual).

Clean-In-Place

Intermittent (non-continuous) cleaning of accumulated silts or scale on the SWRO membrane is necessary to ensure peak membrane performance. The pressure vessel arrays are cleaned one at a time at intervals of six months or more. The cleaning process takes approximately two weeks for each array with the remaining arrays providing the required plant production capacity. The clean-in-place (CIP) process consists of proprietary and non-proprietary acidic and/or alkaline chemicals passing through the membranes and then flushed. The used CIP waste stream would be collected in a separate collection sump, neutralized, and subsequently taken by tanker truck to an appropriate off-site disposal site.

Energy Recovery

Seawater desalination is an energy intensive process and therefore utilizing an energy recovery system is required to recover the energy from the concentrate stream. Various types of energy recovery devices are available and in use and the specific system to be used will be determined during design and/or procurement.

Power Requirements

It is anticipated that a SWRO plant with an initial capacity of 2.5 MGD will require approximately two megawatts (mW) of power to operate. Power in the Montecito area is provided by Southern California Edison (SCE) and it is anticipated that power would be purchased from the SCE grid for this project. SCE has provided a preliminary indication that it is capable of providing power in this range throughout the District’s service boundary;

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however the distribution and design of the power system and those associated costs are unknown at this time.

2. Desalination Plant Site Alternatives

Site Screening Criteria

The SWRO desalination plant site would need to accommodate pretreatment and desalination process facilities, chemical storage facilities, non-process and other appurtenant facilities. It is estimated that the total land area required for a potential ultimate 4.0 MGD SWRO plant would be approximately two acres.

This acreage may be a conservative value, as alternative construction methods could be applied (such as vertical or stacked construction) in order for the desalination facility to occupy less acreage.

In addition to size, additional site screening criteria included land ownership (public ownership preferred), site access (direct from public roadways), topography (flat requiring minimal grading), existing conditions at site (disturbed or not), neighboring land use (adjacent to compatible land uses), proximity to the coastline (less than two miles), elevation (less than 300 feet), and proximity to the District’s major water distribution pipelines.

Identification of Candidate Sites

Similar to the intake site analysis, and applying the above screening criteria, identification of candidate SWRO treatment plant site locations was initially performed using aerial imagery and Geographic Information System (GIS) data to identify property parcel information within the District’s service boundary.

Following this “paper” analysis, field inspections were conducted to more closely analyze each candidate SWRO desalination plant site location. This preliminary reconnaissance survey resulted in the identification of ten sites as shown on Exhibit 4 and listed below in Table 11.

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TABLE 11 – PRELIMINARY CANDIDATE SWRO PLANT SITES Plant Site

Site Description Site Acreage

Approx. Site Elevation (ft) Ownership

P1 Montecito Country Club - Hot Springs Rd 2.64 80 Private P2 Private Lot - 1437 S. Jameson Lane 3.27 60 Private

P3 Private Lot - 115 Tiburon Bay Lane (Orchard) 5 35 Private

P4 District Paden Well & Las Entradas HOA 0.33 75 District

1.0 +/- 70 Private P5 Private Lot - 1510 San Leandro Lane 0.858 65 Private

P6 District Yard - 583 San Ysidro Road 3.03 235 District 0.71 250 District

P7 Private Lot - 1790 N. Jameson Lane 8.85 50 Private P8 Private Lot - 2025 Creekside Road 2.49 90 Private P9 County Yard / Greenwell Preserve 1.8 105 Public

P10 At US 101 Sheffield Drive Off-Ramp 0.62 85 Public

0.60 +/- 80 Public 1.86 80 Private

The largest unknown at this time is the ability to acquire property owned by others. Furthermore, the time and financial investment involved in acquiring property may extend the overall implementation schedule for the project.

One of the sites, P6 – District Yard, is completely owned by the District and this site has been selected as a baseline to which three other sites have been selected for comparison, each representing a different type of property acquisition. These sites are included for illustrative purposes only. There are likely additional sites that could accommodate the desalination plant. Future site-specific investigations and discussions with property owners would be required prior to proceeding with any specific site. The District has not yet selected a “preferred” or proposed specific site for the intakes, discharge, or desalination plant.

The sites selected for further analysis are as shown in Exhibit 5 and described in Table 12 below.

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TABLE 12 – SWRO DESALINATION PLANT SITE OPTIONS SWRO

Treatment Plant Site

Site Description Site Acreage

Approx. Site Elevation (ft) Ownership

P3 Private Lot - 115 Tiburon Bay Lane (Orchard) 5 35 Private

P6 District Yard - 583 San Ysidro Road

3.03 235 District

0.71 250 District

P9 County Yard / Greenwell Preserve 1.8 105 Public

P10 At US 101 Sheffield Drive Off-Ramp

0.62 85 Public

0.60 +/- 80 Public

1.86 80 Private

The three options (to the base site option of P6) listed above were also selected based on a preliminary assessment of the conveyance facilities necessary to connect the desalination plant site to the intake, discharge and District distribution system as described below.

3. Desalination Plant Site Options

The following section discusses the advantages and disadvantages associated with constructing a SWRO desalination facility at each of the four locations identified in the previous section. The base option considers siting the SWRO desalination plant on property currently owned by the District at 583 San Ysidro Road. This is considered as the base option due to the fact that property acquisition is not required. The remaining three site options are analyzed herein, but it is important to note that the ability to acquire these properties is unknown at this time.

Site P6 (Base Option – District Yard)

The P6 site is located at 583 San Ysidro Road and currently serves as the Montecito Water District Headquarters and Distribution Operations Yard. Listed below are the advantages and disadvantages of constructing a SWRO desalination facility on the P6 site.

Advantages related to constructing a SWRO facility on the site are:

Property is owned by the District; Previously disturbed land, therefore minimizing or avoiding effects on sensitive

habitat/species; Adequate space for construction of SWRO plant and ancillary facilities; Property contains water pump station and acts as equipment and material storage

yard, therefore a SWRO plant will not be in conflict with existing land use; Surrounding land use is mixture of commercial, institutional and residential;

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Minimal amount of product water conveyance pipeline required as it is located adjacent to major distribution transmission mains.

Disadvantages related to constructing a SWRO facility on the site are:

Site is located more than 1-½ miles from shoreline, requiring feedwater and concentrate discharge pipelines to be routed from shoreline to site;

Site elevation (approximately 250 feet) would require additional energy consumption of feedwater pump station to deliver water from intake to SWRO plant site;

Feedwater pipeline and concentrate discharge pipeline would need to cross under both US 101 and the Union Pacific Rail Road.

The P6 Site is a feasible site option for locating a SWRO desalination facility in the central region of the District service boundary since it is located on property completely owned by the District. Exhibit 6 provides a conceptual layout for a 2.5 MGD desalination plant with room for future expansion to a 4.0 MGD plant. This conceptual layout has been prepared with the sole purpose of illustrating the footprint of this proposed facility. It is assumed that this layout would be evaluated and optimized as the project progresses.

This conceptual layout impacts several existing on-site facilities including storage buildings, a mechanic’s shop, and employee housing. Impact on these facilities will need to be evaluated in further detail by the District.

Site P9 (Option 1 - County Yard/Greenwell Preserve)

The P9 site is located in Summerland near the intersection of Asegra Road and Greenwell Avenue. This property is currently owned by the County of Santa Barbara and has an existing parking lot and structure located on the site. Listed below are the advantages and disadvantages of constructing a SWRO desalination facility on the P9 site.

Advantages related to constructing a SWRO facility on the site are:

Previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Adequate space for construction of SWRO plant and ancillary facilities; Site elevation (approximately 105 feet) would minimize energy consumption of

feedwater pump station.

Disadvantages related to constructing a SWRO facility on the site are:

Property is not owned by the District; Existing topography of site may require additional grading to maximize area.

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Site P10 (Option 2 – Intersection of Sheffield Drive Off-Ramp & North Jameson)

The P10 site is located near the intersection of the US 101 Sheffield Drive off-ramp. This site considers the combination of three individual properties made up of private property, County of Santa Barbara property and County right-of-way off of Sheffield Drive. The private property is partially developed, and the County property and right-of-way appears to be vacant. Listed below are the advantages and disadvantages of constructing a SWRO desalination facility on the P10 site.

Advantages related to constructing a SWRO facility on the site are:

Portions of the site contains previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Adequate space for construction of SWRO plant and ancillary facilities if all three properties are combined;

If site is also used for seawater intake and brine discharge, this would eliminate these conveyance pipelines and associated capital and operation and maintenance costs.

Disadvantages related to constructing a SWRO facility on the site are:

None of these properties are owned by the District; Possibly complicated site acquisition due to different property owners.

Site P3 (Option 3 – Tiburon Bay Orchard Site)

The P3 site is generally located off of North Jameson Lane east of Hixon Road and west of Tiburon Bay Lane. This site is private property that is currently being used for agricultural purposes. Listed below are the advantages and disadvantages of constructing a SWRO desalination facility on the P3 site.

Advantages related to constructing a SWRO facility on the site are:

Previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Adequate space for construction of SWRO plant and ancillary facilities; Site located less than ½ mile from shoreline which would minimize length of

feedwater and concentrate discharge pipelines; Site elevation (approximately 35 feet) would minimize energy consumption of

feedwater pump station.

Disadvantages related to constructing a SWRO facility on the site are:

Property is not owned by the District; Would remove active agricultural land from production;

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Feedwater pipeline and concentrate discharge pipeline (to new outfall) would need to cross under both US 101 and the Union Pacific Rail Road;

Surrounding land use is predominantly residential.

D. PRODUCT WATER CONVEYANCE

1. Overview of Existing Water Distribution System

The District’s distribution system is generally comprised of two surface water treatment plants that treat water from the Doulton Tunnel and Jameson Lake, three pumping stations that convey water from the South Coast Conduit (SCC) to various areas of the distribution system, nine storage reservoirs predominantly located in the foothills of Montecito, 27 individual pressure zones and approximately 113 miles of pipeline. The system generally operates via gravity whereby the storage reservoirs located at the higher elevations in the Montecito foothills are filled by either the District’s Bella Vista Treatment Plant or water pumped from the SCC. Water is conveyed by the extensive pipeline network and served at acceptable pressures through the use of pressure reducing stations.

Pipelines range in size from 2-inches to 18-inches with the majority of the distribution system network (approximately 74%) comprised of 6-inch and 8-inch diameter pipelines. These pipelines primarily act as distribution pipes to deliver water directly to customers, but in many instances also function as transmission mains which act as a part of the “backbone” for the distribution system, conveying water from reservoirs and pump stations to the various pressure zones of the system. The majority of the District’s pipelines (83%) are made of either cast or ductile iron with the oldest pipes over 90 years old. Approximately 20% (23 miles) of the distribution system pipe was installed before 1930.

It is important to understand the make-up of the existing distribution pipe network, as the introduction of desalinated water can create issues with older pipelines. For example, the introduction of desalinated water into an un-lined cast iron pipeline that has flowed in one direction for several decades, and is then subjected to flow in the opposite direction, may generate water quality issues due to the breakage and disruption of tubercles10.

With elevations ranging from near sea level to over 1,800-feet, there are 27 individual pressure zones to reduce and regulate system pressures throughout the distribution system.

2. Product Water Connection Requirements

Introducing desalinated water into the existing distribution system requires an understanding of the distribution system hydraulics to ensure this new source can be utilized to the greatest extent possible.

10 A small knob or button of rust formed on the inside of an iron pipe.

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With this objective in mind, the following connection requirements and considerations were established to determine where the product water supply (permeate) would be introduced for each desalination plant site option.

Connect to the Park-Lane Romero pressure zone. This zone is the largest pressure zone, is connected to over 2 MG of storage, and the Romero Pump Station can “wheel” water via the highline transmission pipeline to storage reservoirs in the foothills;

Connect to an existing pipeline of 12-inches or larger to maintain acceptable pipeline velocities and reduce friction losses.

3. Product Water Connection Analysis

The product water conveyance pipeline alignment and connection analysis identified preliminary pipeline alignments and points of connection to the system based on current knowledge of the system for the sole purpose of estimating pipeline length. These alignments represent possible options for routing water from the SWRO desalination plant to the distribution system. It is expected that alignment alternatives would be analyzed and optimized as part of subsequent studies.

Evaluation of alternative product water conveyance pipeline alignments and points of connection began with a review of the District’s distribution system to determine where available connection points to the Park-Lane Romero pressure zone were located. Once these possible points of connection were identified, the existing pipelines were reviewed to determine if the point of connection was to a 12-inch or larger pipeline. If the nearest pipeline was less than 12-inches in diameter, the proposed product water pipeline alignment was extended until it reached a 12-inch or larger pipeline.

Product water conveyance pipeline alignments were generated from each of the ten SWRO desalination plant site options to the point of connection using the criteria stated above.

Table 13 below contains the results of this analysis. As Table 13 indicates, the length of product water conveyance pipeline ranges from negligible to nearly 12,000 feet. Opportunities may exist for the District to replace aging or undersized pipe along each alignment, and this should be evaluated in subsequent studies.

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TABLE 13 – PRODUCT WATER CONVEYANCE PIPELINE LENGTHS SWRO Desalination Plant Site Total Length of Product Water Conveyance

Pipe Required (ft) P1 3,500 P2 6,900 P3 10,400 P4 8,300 P5 5,700 P6 0 P7 8,800 P8 6,700 P9 11,800 P10 6,200

It is assumed that the new product water conveyance pipeline would be 16 inches in diameter in order to allow expansion of the desalination plant to an ultimate capacity of 4.0 MGD.

E. PROJECT ALTERNATIVES

1. Methodology

The above sections of this report have noted the advantages and disadvantages for the intake alternatives, concentrate discharge alternatives, SWRO desalination plant site alternatives and product water conveyance system considerations. These components of the project were configured as complete system alternatives to develop a preliminary feasibility assessment of seawater desalination as a supplemental water source of supply to the District. In addition to the infrastructure evaluated above, two additional components were evaluated: feedwater pipelines and brine pipelines.

For this study, it is assumed that the feedwater and brine pipelines would be constructed along the same alignment and possibly in a shared trench. These alignments were developed along public roadways for the sole purpose of estimating pipeline length. It is expected that alignment alternatives would be analyzed and optimized as part of subsequent studies.

2. Development of System Alternatives

Potentially over fifty SWRO system combinations can be formulated from the various SWRO desalination plant site, intake site and concentrate discharge site alternatives.

Table 14 below contains a matrix which quantifies the approximate length of feedwater conveyance pipeline required to bring raw seawater from each alternative intake location to each alternative SWRO desalination plant site.

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TABLE 14 – FEEDWATER CONVEYANCE PIPELINE ANALYSIS

SWRO Plant Sites

Intake Sites

Feedwater Conveyance Pipeline Length (ft)

I1 I2 I3 I4 I5

P1 4,000 9,000 12,000 13,000 18,000

P2 9,000 4,000 6,000 8,000 13,000

P3 13,000 1,000 2,000 3,000 8,000

P4 16,000 4,000 7,000 4,000 7,000

P5 11,000 3,000 5,000 6,000 11,000

P6 17,000 8,000 11,000 12,000 16,000

P7 15,000 2,000 1,000 2,000 7,000

P8 18,000 7,000 4,000 1,000 5,000

P9 26,000 14,000 13,000 10,000 6,000

P10 18,000 7,000 4,000 0 5,000

As illustrated by Table 14, feedwater conveyance pipelines could range from negligible to 26,000 feet. For this study, it is assumed that the feedwater conveyance pipeline will be 20-inches in diameter.

For brine discharge, two possibilities were considered: (1) a new brine discharge outfall at the same location as the intake; and (2) connection to the existing MSD treated wastewater outfall. For the co-located intake and discharge combinations, the brine pipeline lengths are identical to the feedwater pipeline lengths shown in Table 14 above and repeated for discharge sites D1 through D5 in Table 15 below. For the combinations involving connections to the MSD outfall (D6) the brine pipeline lengths are shown in Table 15 below. For this study, it is assumed that the brine conveyance pipeline will be 16-inches in diameter.

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TABLE 15 – BRINE CONVEYANCE PIPELINE ANALYSIS

SWRO Plant Sites

Brine Discharge Sites

Brine Conveyance Pipeline Length (ft)

D1 D2 D3 D4 D5 D6

P1 4,000 9,000 12,000 13,000 18,000 3,000

P2 9,000 4,000 6,000 8,000 13,000 8,000

P3 13,000 1,000 2,000 3,000 8,000 13,000

P4 16,000 4,000 7,000 4,000 7,000 15,000

P5 11,000 3,000 5,000 6,000 11,000 11,000

P6 17,000 8,000 11,000 12,000 16,000 16,000

P7 15,000 2,000 1,000 2,000 7,000 14,000

P8 18,000 7,000 4,000 1,000 5,000 18,000

P9 26,000 14,000 13,000 10,000 6,000 26,000

P10 18,000 7,000 4,000 0 5,000 17,000

As illustrated by Table 15, brine conveyance pipelines could range from negligible to 26,000 feet.

As mentioned earlier, only one of the SWRO plant site alternatives (P6 – District Yard) is entirely owned by the District. All other alternatives identified are either privately owned, publicly owned or a combination of both. Due to the conceptual nature of this study, due diligence regarding property acquisition was not included as a part of this work.

As previously discussed, four of the desalination plant site options have been identified for further analysis: a “Base Option” and three alternatives based on desalination plant sites P3, P9 and P10. For each of the options, an intake location was selected with the assumption that the brine discharge would be co-located at the same site denoted as the “A” alternative and correspondingly a “B” alternative was identified for connecting that desalination plant site with the existing MSD outfall. The logic for selecting the intake location for each desalination plant site was based on selecting the intake location with the shortest feedwater pipeline length to the site with the exception of P9 (County Yard / Greenwell Preserve) where the nearest Intake location (I5) was considered to be questionably feasible.

Exhibits 7 through 10 illustrate the feedwater, brine discharge (both to the new brine discharge outfall and the existing MSD outfall) and product water conveyance pipelines associated with these four system alternatives. Table 16 below contains a summary of the plant and conveyance facilities along with a conceptual cost for each alternative. These estimates do not include costs for property or easement acquisition, which would be required for all sites except for Plant Site P6 – District Yard.

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TABLE 16 – SUMMARY OF SWRO SYSTEM ALTERNATIVES

Attributes

Base Option (P6 & I2) Sub-Seafloor Drains Option 1 (P9 & I4) Option 2 (P10 & I4) Option 3 (P3 & I2)

A B A B A B A B

Plant Site Acreage 3.74 1.8 3.08 5

Plant Site Elevation (ft) 250 105 85 35

Subsurface Intake Length (ft) 5,400 7,200 7,200 5,400

Feedwater Pipe Length (ft) 8,000 10,000 0 1,000

Product Water Pipe Length (ft) 0 11,800 6,200 10,400

Concentrate (Brine) Pipe Length (ft) 8,000 16,000 10,000 26,000 0 17,000 1,000 13,000

Ocean Outfall Length (ft) 1,850 0 2,300 0 2,300 0 1,850 0

Estimated Cost of Pipe Infrastructure $20,800,000 $19,100,000 $30,500,000 $30,500,000 $21,500,000 $21,800,000 $19,000,000 $18,700,000

Estimated Cost of Plant Infrastructure $30,000,000 $30,000,000 $30,000,000 $30,000,000 $30,000,000 $30,000,000 $30,000,000 $30,000,000

Estimated Engineering/Legal/ Admin/Cont.

$20,300,000 $19,640,000 $24,200,000 $24,200,000 $20,600,000 $20,720,000 $19,600,000 $19,480,000

Total Estimated Cost $71,100,000 $68,740,000 $84,700,000 $84,700,000 $72,100,000 $72,520,000 $68,600,000 $68,180,000

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The four SWRO system alternatives presented in Table 16 are based on the use of a sub-seafloor drain as the intake system. As previously noted, Intake Site I1 may be a candidate for a slant well intake system. Therefore, to identify and evaluate this intake system an alternative considering the use of slant wells at Intake Site I1 is presented below. This alternative also uses site P6 – District Yard for the SWRO plant site since this is the only property completely owned by the District. Table 17 provides a summary of this variation of the Base Option. Exhibit 11 illustrates the configuration of this variation of the Base Option.

TABLE 17 – SWRO SYSTEM ALTERNATIVE CONSIDERING SLANT WELLS

Attributes Base Option Variation (P6 & I1) Slant Wells

A B

Plant Site Acreage 3.74

Plant Site Elevation (ft) 250

Number of Slant Wells (ea) 6

Feedwater Pipe Length (ft) 17,000

Product Water Pipe Length (ft) 0

Concentrate (Brine) Pipe Length (ft) 17,000 16,000

Ocean Outfall Length (ft) 1,900 0

Estimated Cost of Pipe Infrastructure $31,500,000 $26,900,000

Estimated Cost of Plant Infrastructure $30,000,000 $30,000,000

Estimated Engineering/Legal/Admin/Cont. $24,600,000 $22,760,000

Total Estimated Cost $86,100,000 $79,660,000

3. Conceptual Project Alternatives

The options as shown and described in the previous section provide a suitable framework for evaluating the feasibility of seawater desalination as a supplemental source of supply for the District.

Additional studies and investigations of these conceptual alternatives are recommended to determine the preferred alternative, with the understanding that intake sites and plant sites may be adjusted as the investigation proceeds based on factors such as property acquisition, stakeholder input and permitting issues that may arise.

A summary discussion of advantages, disadvantages, and costs of each of these conceptual alternatives is provided below.

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Base Option (Sub-Seafloor Drains)

The Base Option considers siting the SWRO desalination plant at Site P6 which is located at the District’s Yard at 583 San Ysidro Road. This site currently serves as the District’s Headquarters and Distribution Operations Yard. Raw seawater would be provided by a sub-surface intake system (HDD sub-seafloor drain) located at Intake Site I2, which is located at the former Miramar Hotel site south of Jameson Lane and west of Posilipo Lane. Concentrate would be discharged to either a new dedicated outfall co-located with the intake at Site I2, or alternatively would be conveyed to the existing Montecito Sanitary District treated wastewater outfall. The Base Option with all of its associated conveyance pipelines is shown in Exhibit 7.

Below is a summary of the advantages and disadvantages for the Base Option and special challenges that should be considered for further evaluation.

Advantages for the Base Option include:

Plant Site P6 property is owned by the District; Plant Site P6 property is previously disturbed land, therefore minimizing or avoiding

effects on sensitive habitat/species; Plant Site P6 has adequate space for construction of SWRO plant and ancillary

facilities; Plant Site P6 contains water pump station and acts as equipment and material storage

yard, therefore a SWRO plant will not be in conflict with existing land use; Land use surrounding Plant Site P6 is a mixture of commercial, institutional and

residential; Minimal amount of product water conveyance pipeline required as Plant Site P6 is

located adjacent to major distribution and transmission mains; Intake Site I2 is previously disturbed land, therefore assume no sensitive

habitat/species; Intake Site I2 has adequate space for drilling equipment; Intake Site I2 provides ease of access for both construction and future operation and

maintenance of intake facilities; Intake Site I2 is relatively close to the shoreline which maximizes length of intake

underneath the ocean floor; Existing elevated railroad berm may provide a barrier to protect facilities from coastal

erosion at Site I2; Intake Site I2 is centrally located relative to potential desalination plant site.

Disadvantages for the Base Option include:

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Plant Site P6 is located more than 1-½ miles from shoreline, requiring feedwater and concentrate discharge pipelines to be routed from shoreline to site;

Plant Site P6 elevation (approximately 250 feet) would require additional energy consumption of feedwater pump station to deliver water from intake to SWRO plant site;

Feedwater and concentrate discharge pipelines would need to cross under US 101; Intake Site I2 property is not owned by the District; Intake will cross beneath Union Pacific Rail Road tracks; Concentrate discharge will cross beneath Union Pacific Rail Road tracks; Intake Site I2 is potentially within floodway and/or coastal erosion zone.

The estimated cost to implement the Base Option is between $68.7M and $71.1M depending on which brine discharge outfall alternative is considered.

Base Option (Slant Well Variation)

This variation of the Base Option also considers siting the SWRO desalination plant at Site P6 which is located at the District’s Yard at 583 San Ysidro Road. This site currently serves as the District’s Headquarters and Distribution Operations Yard. However, for this option, raw seawater would be provided by a sub-surface intake system (slant wells) located at Intake Site I1, which is located at the eastern edge of the Santa Barbara Cemetery site near Channel Drive. Concentrate would be discharged to either a new dedicated outfall co-located with the intake at Site I1, or alternatively would be conveyed to the existing Montecito Sanitary District treated wastewater outfall. This variation of the Base Option with all of its associated conveyance pipelines is shown in Exhibit 11.

Below is a summary of the advantages and disadvantages for the Base Option (Slant Well Variation) and special challenges that should be considered for further evaluation.

Advantages for the Base Option (Slant Well Variation) include:

Plant Site P6 property is owned by the District; Plant Site P6 property is previously disturbed land, therefore minimizing or avoiding

effects on sensitive habitat/species; Plant Site P6 has adequate space for construction of SWRO plant and ancillary

facilities; Plant Site P6 contains water pump station and acts as equipment and material storage

yard, therefore a SWRO plant will not be in conflict with existing land use; Land use surrounding Plant Site P6 is a mixture of commercial, institutional and

residential;

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Minimal amount of product water conveyance pipeline required as Plant Site P6 is located adjacent to major distribution and transmission mains;

Intake Site I1 is previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Intake Site I1 has adequate space for drilling equipment; Intake Site I1 surrounding land use is institutional with limited residential; Intake Site I1 is relatively close to the shoreline which maximizes length of intake

underneath the ocean floor; Intake Site I1 provides ease of access for both construction and future operation and

maintenance; Relatively close to a convenient crossing beneath both the railroad and US 101 for

feedwater and brine pipelines.

Disadvantages for the Base Option (Slant Well Variation) include:

Plant Site P6 is located more than 1-½ miles from shoreline, requiring feedwater and concentrate discharge pipelines to be routed from shoreline to site;

Plant Site P6 elevation (approximately 250 feet) would require additional energy consumption of feedwater pump station to deliver water from intake to SWRO plant site;

Intake Site I1 is not owned by the District; Intake Site I1 elevation (60 feet) will result in increased length of submersible pump

equipment (drop pipe, power cable, etc.); Intake Site I1 has uncertainties regarding bluff erosion impacts to on-shore pipe or

well casing segments; Slant wells may adversely affect local groundwater quality or existing well operation.

The estimated cost to implement the Base Option (Slant Well Variation) is between $79.6M and $86.1M depending on which brine discharge outfall alternative is considered.

Option 1

Option 1 considers siting the SWRO desalination plant at Site P9, which is located in Summerland near the intersection of Asegra Road and Greenwell Avenue. This property is currently owned by the County of Santa Barbara and has an existing parking lot and structure located on the site. Raw seawater would be provided by a sub-surface intake system (HDD sub-seafloor drain) located at Intake Site I4, which is situated near the US 101 Sheffield Drive off-ramp. Intake Site I4 considers the combination of two individual properties made up of private property and property owned by the County of Santa Barbara. The private property is partially developed, and the County property appears to be vacant. Concentrate would be discharged to either a new dedicated outfall co-located with the intake at Site I4, or

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alternatively would be conveyed to the existing Montecito Sanitary District treated wastewater outfall. Option 1 with all of its associated conveyance pipelines is shown in Exhibit 8.

Below is a summary of the advantages and disadvantages for the Option 1 and special challenges that should be considered for further evaluation.

Advantages for Option 1 include:

Plant Site P9 is previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Plant Site P9 has adequate space for construction of SWRO plant and ancillary facilities;

Plant Site P9 elevation (approximately 105 feet) would minimize energy consumption of feedwater pump station;

Portions of Intake Site I4 are previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Intake Site I4 provides ease of access for both construction and future operation and maintenance of intake facilities;

Intake Site I4 has adequate space for drilling equipment.

Disadvantages for Option 1 include:

Plant Site P9 property is not owned by the District; Existing topography of Plant Site P9 may require additional grading to maximize area

for SWRO site; Plant Site P9 location requires longest product water pipeline connection compared to

the other three alternatives; Intake Site I4 property is not owned by the District, and combination of private and

public ownership could make site acquisition more complicated; Intake Site I4 is a relatively long distance from the shoreline which reduces length of

intake beneath ocean floor; Intake Site I4 elevation (85 feet) will result in increased length of submersible pump

equipment (drop pipe, power cable, etc.); Properties surrounding Intake I4 are predominantly residential; Intake I4 will cross beneath US 101 including bridge piers and the Union Pacific Rail

Road tracks; Concentrate discharge will also cross beneath US 101 including bridge piers and the

Union Pacific Rail Road tracks.

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The estimated cost to implement Option 1 is approximately $84.7M regardless of which brine discharge outfall alternative is considered.

Option 2

Option 2 considers siting the SWRO desalination plant at Site P10, which is located near the intersection of the US 101 Sheffield Drive off-ramp. Site P10 considers the combination of three individual properties made up of private property, County of Santa Barbara property and County right-of-way off of Sheffield Drive. The private property is partially developed, and the County property and right-of-way appear to be vacant. Raw seawater would be provided by a sub-surface intake system (HDD sub-seafloor drain) located at Intake Site I4. Intake Site I4 also considers the use of the above mentioned properties, with the exception of the County right-of-way. Concentrate would be discharged to either a new dedicated outfall co-located with the intake at Site I4, or alternatively would be conveyed to the existing Montecito Sanitary District treated wastewater outfall. Option 2 with all of its associated conveyance pipelines is shown in Exhibit 9.

Advantages for Option 2 include:

Portions of Plant Site P10 and Intake Site I4 contain previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Plant Site P10 provides adequate space for construction of SWRO plant and ancillary facilities if all three properties are combined;

With Plant Site P10 and Intake Site I4 co-located, this would eliminate both feedwater and brine conveyance pipelines and the associated capital and operation and maintenance costs;

Intake Site I4 provides ease of access for both construction and future operation and maintenance of intake facilities;

Intake Site I4 has adequate space for drilling equipment.

Disadvantages for Option 2 include:

None of the three properties are owned by the District; Possibly complicated site acquisition due to different property owners; Intake Site I4 is a relatively long distance from the shoreline which reduces length of

intake beneath ocean floor; Intake Site I4 elevation (85 feet) will result in increased length of submersible pump

equipment (drop pipe, power cable, etc.); Properties surrounding Plant Site P10 and Intake Site I4 are predominantly

residential; Intake I4 will cross beneath US 101 including bridge piers and the Union Pacific Rail

Road tracks;

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Concentrate discharge will also cross beneath US 101 including bridge piers and the Union Pacific Rail Road tracks.

The estimated cost to implement Option 2 is between $72.1M and $72.5M depending on which brine discharge outfall alternative is considered.

Option 3

Option 3 considers siting the SWRO desalination plant at Site P3, which is generally located off of North Jameson Lane east of Hixon Road and west of Tiburon Bay Lane. Site P3 is private property that is currently being used for agricultural purposes. Raw seawater would be provided by a sub-surface intake system (HDD sub-seafloor drain) located at Intake Site I2, which is located at the former Miramar Hotel site south of Jameson Lane and west of Posilipo Lane. Concentrate would be discharged to either a new dedicated outfall co-located with the intake at Site I2, or alternatively would be conveyed to the existing Montecito Sanitary District treated wastewater outfall. Option 3 with all of its associated conveyance pipelines is shown in Exhibit 10.

Advantages for Option 3 include:

Plant Site P3 is previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Plant Site P3 provides adequate space for construction of SWRO plant and ancillary facilities;

Plant Site P3 located less than ½ mile from shoreline which would minimize length of feedwater and concentrate discharge pipelines;

Plant Site P3 elevation (approximately 35 feet) would minimize energy consumption of feedwater pump station;

Intake Site I2 is previously disturbed land, therefore minimizing or avoiding effects on sensitive habitat/species;

Intake Site I2 has adequate space for drilling equipment; Intake Site I2 provides ease of access for both construction and future operation and

maintenance of intake facilities; Intake Site I2 is relatively close to the shoreline which maximizes length of intake

underneath the ocean floor; Existing elevated railroad berm may provide a barrier to protect facilities from coastal

erosion at Site I2; Intake Site I2 is centrally located relative to potential desalination plant site.

Disadvantages for Option 3 include:

Plant Site P3 property is not owned by the District;

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Construction of a SWRO plant at Site P3 would remove active agricultural land from production;

Feedwater pipeline and concentrate discharge pipeline (to new outfall) would need to cross under US 101;

Land use surrounding Plant Site P3 is predominantly residential; Intake Site I2 property is not owned by the District; Intake will cross beneath Union Pacific Rail Road tracks; Concentrate discharge will cross beneath Union Pacific Rail Road tracks; Intake Site I2 is potentially within floodway and/or coastal erosion zone.

The estimated cost to implement Option 3 is between $68.1M and $68.6M depending on which brine discharge outfall alternative is considered.

IV. PROJECT IMPLEMENTATION A. REGULATORY & PUBLIC CONSIDERATIONS

Potential regulatory permitting and related challenges were considered in this feasibility study as part of the overall desalination technology, alternatives evaluation and feasibility assessment. This study is not intended to be a comprehensive or detailed regulatory permitting evaluation, which is recommended as part of the “Next Steps” listed below. Rather, this feasibility study focuses on certain key regulatory permitting decision drivers that are considered most likely to influence the desalination alternatives, site selection and feasibility. Successful implementation of a desalination project not only requires technical, financial and political/institutional feasibility, but also must receive strong community support and pass the test of multiple layers of local, state and federal regulatory permitting review and approval processes. The following are key regulatory considerations that factored into this feasibility study. A more comprehensive (but not exhaustive) list of potential regulatory permits and approvals is provided below. As indicated in the “Next Steps” section below, one of the essential recommended tasks is to conduct limited field investigations, refine the overall desalination concept, and reach out to key stakeholders and regulatory agencies to further define and refine the issues, process and approaches to addressing each required permit or approval.

1. Key Regulatory Considerations Community support – Strong community support will be important to ensure

project acceptance and the timeliness of approvals. As demonstrated at the September 18, 2014 community meeting, the Montecito community strongly supports desalination. A robust community participation program is recommended as one of the Next Steps.

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Subsurface intakes – In order to expedite permitting and implementation, it is recommended the District pursue a subsurface intake, which is the intake method preferred by regulatory permitting agencies and the environmental community. Specific subsurface intake technologies will be evaluated further in future phases, should the District proceed.

Desalination concentrate discharge – This feasibility study investigates blending the concentrate discharge with the existing MSD outfall, and also considers a new outfall constructed concurrently with the new intake system using the HDD construction method. Both options would include a concentrate discharge diffuser to ensure compliance with existing and anticipated future California Ocean Plan requirements. Recommended Next Steps also include conducting limited marine surveys to ensure proper siting and design of the intake and discharge facilities, given the potential for sensitive marine habitat off of the Montecito coast.

“Right-sized” community-scale facility – The feasibility study identifies the recommended desalination plant sizing, in order to achieve “water security” through a safe, reliable, drought-proof water supply. Recommended Next Steps include updating the District’s Urban Water Management Plan regarding desalination in light of other existing and potential future water supply portfolio options such as conservation, recycled water, imported water, and groundwater.

Sensitive beach habitat – The feasibility study recommends further study of subsurface intake options that avoid beach construction, and allow the intake facility on-shore “launch” site to be well-removed from sensitive beach and coastal bluff areas. Recommended Next Steps include limited terrestrial biological surveys to identify and where possible avoid sensitive habitat and species.

Coastal erosion hazards – The recommended subsurface intake options would avoid beach or bluff construction, thereby avoiding issues and regulatory permitting challenges associated with coastal erosion hazards. Recommended Next Steps include identifying applicable coastal/bluff hazard lines to avoid or mitigate any remaining coastal hazard concerns.

Coastal groundwater effects – The recommended subsurface intake options would avoid potential groundwater effects associated with other intake methods. Recommended Next Steps include conducting limited offshore and onshore geologic investigations to better understand and map coastal geology, develop hydrogeologic groundwater modeling to predict intake system performance and effects, and initiate a pilot project to further define and refine the desalination intake system.

Other coastal resources (sensitive habitat, parking, visual impacts, land area) – The subsurface intake option would substantially avoid or reduce impacts to coastal resources by allowing the on-shore “launch” site to be well-removed from the beach and bluffs. Recommended Next Steps include developing conceptual design plans for intake and discharge facilities as well as associated conveyance lines and pump

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stations, in order to properly site and design these facilities to avoid or minimize potential adverse effects upon sensitive coastal resources.

Terrestrial resources – The identified on-shore facilities almost exclusively utilize existing disturbed sites, easements or public roads, in order to avoid or minimize potential adverse effects upon terrestrial resources such as sensitive biological habitat and species. Recommended Next Steps include refining the facility alignments and conceptual design, and conducting limited field surveys including biological and cultural/historic resources. This effort is recommended to include a detailed review and consistency analysis with applicable regulations, plans and policies, including the Santa Barbara County Comprehensive Plan, Montecito Community Plan, Santa Barbara County Coastal Zoning Ordinance and other relevant regulations, plans and policies.

2. Potential Regulatory Permits and Approvals Required

The following is a partial list of potential regulatory permits and approvals that may be required for a Montecito Desalination Facility. The specific regulatory permits/approvals and associated processes would be dependent on the desalination option(s) selected by the Board of Directors for further analysis and implementation. Recommended Next Steps include refining the desalination options selected for further study, and initiating informal regulatory agency consultation to better understand and define the issues, processes, technical studies and potential solutions to address each required permit or approval.

CEQA (California Environmental Quality Act) Compliance – CEQA compliance is required before any local or state agency can issue a permit or approval for the project. As part of the CEQA process, in addition to public input, the District would consult with other applicable agencies and organizations, including but not limited to:

California Department of Fish and Wildlife (California Endangered Species Act compliance)

Native American consultation State Water Resources Control Board (for any “CEQA Plus” analysis should the

District depending on project funding) NEPA (National Environmental Policy Act) Compliance – NEPA compliance is

required for any federal agency permit, approval or funding (see list of agencies below).

Project Approval – the Montecito Water District would be the CEQA "Lead Agency" and be responsible for the initial Project Approval, following a determination of CEQA compliance.

Montecito Sanitary District (MSD) – MSD approval would be required for the discharge option involving connection to and blending with the MSD outfall. This approval/agreement with MSD would be coordinated closely with the NPDES permit,

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State Lands Commission lease/amendment, and Coastal Development Permit noted below.

County of Santa Barbara – the Project would require several discretionary and ministerial permits and approvals from the County of Santa Barbara and its various agencies or departments, including:

County Planning Department County Parks (should facilities affect County park land) Montecito Planning Commission:

• Preliminary Development Plan • Coastal Development Permit (CDP) – for all on-shore facilities

County Board of Supervisors • Local Coastal Program Amendment (LCPA) for possible parcel

rezoning to Public Works County Public Health Department (well permit)

State Lands Commission – (SLC) – the MSD currently operates its existing outfall under a lease from the State Lands Commission (approved 12/10/10). Changes in use of this outfall, such as the addition of desalination concentrate discharge, may require a lease amendment, in addition to a new or amended NPDES and Coastal Development Permit as noted below.

U.S. Army Corps of Engineers (USACE) – in addition to any upland crossings of existing streams, the project would require various permits or approvals from the USACE for any intake or discharge option that involved new construction in the open ocean, including:

Clean Water Act Section 404 Permit Rivers and Harbors Act Section 10 Permit U.S. Fish and Wildlife Service, Endangered Species Act, Section 7 Consultation National Marine Fisheries Services, Marine Mammal Protection Act compliance National Marine Fisheries Services, Magnuson-Stevens Fishery Conservation and

Management Act compliance State Historic Preservation Officer, National Historic Preservation Act, Section 106

Consultation U.S. Coast Guard, Rivers and Harbors Act, Section 10 Consultation Property Owners - the Coastal Commission will require that the District obtain

permission from any affected property owner(s) prior to Coastal Development Permit issuance, including encroachment permits, easements and/or temporary or permanent land acquisition from Caltrans, the Union Pacific Railroad, private property owners, and/or others.

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California Coastal Commission – following County CDP approval and/or LCPA, the project would be subject to review and approval by the California Coastal Commission for a Coastal Development Permit (for marine facilities below the mean high tide, including desalination intakes and discharge), LCPA approval, and Coastal Zone Management Act consistency determination associated with any required federal permit or approval.

Regional Water Quality Control Board (RWQCB) – the project would require various permits and approvals from the RWQCB associated with determining consistency with the California Ocean Plan, Porter-Cologne Water Quality Control Act, NPDES Permit program, and the Clean Water Act Section 401 certification process.

State Water Resources Control Board (SWRCB) – Drinking Water Program – following construction, the project would require approval by DWR for a new drinking water system Domestic Water Supply Permit.

Santa Barbara County Air Pollution Control District – the desalination plant would require approval from the APCD, under Rule 201, Authority to Construct and Permit to Operate.

B. PROJECT DELIVERY AND SCHEDULE CONSIDERATIONS

This section provides a general overview of potentially available project delivery methods as well as schedule considerations for this project.

1. Conventional Delivery

Conventional project delivery, typically referred to as Design-Bid-Build (DBB), is the most prevalent delivery model for construction projects in the United States. For DBB projects, the owner contracts with a consulting engineering firm to design the project and produce bid documents which include construction drawings and technical specifications. These documents are then publicly advertised inviting contractors to submit hard dollar construction bids to complete the project. The project is awarded through a competitive bidding process, which typically awards the contract to the lowest bidder. The contractor then builds the project and the owner takes ownership and operates the project after all construction is complete and has passed acceptance tests.

While conventionally delivered projects closely follow the design-bid-build path, groundwater wells deviate slightly from this sequence due to the technical nature associated with this infrastructure. For groundwater wells, the design is typically not complete at the time of contractor bidding because the actual hydrogeologic conditions are unknown. Therefore, the contractor is relied upon during the initial construction phase of the well to collect and provide additional technical information to the engineer. The engineer uses the information collected during the initial construction phase to finalize the well design, which

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is then completed by the same contractor. This is an important example to describe, as it is anticipated that the sub-surface intake system would follow this conventional delivery model.

2. Alternative Delivery

There are many alternatives to conventional project delivery, however only the Design-Build-Operate-Finance (DBOF) model is considered for portions of this project.

Under the DBOF model a company is selected to design, build, operate, maintain and finance the project with all assets owned by a private sector entity. The successful entity finances construction and operation of the project in return for revenue which is normally paid in two forms, an availability charge, and a volume charge. A proving period is normally incorporated into the contract to ensure the project is operating to the specifications established by the owner. A high level of involvement of the owner would be required prior to involving the private sector entity to establish performance criteria and guarantee requirements for design, construction, operation, maintenance and finance of the project.

3. Idealized Project Delivery & Implementation Schedule

Based on the District’s desire to implement desalinated water as a supply source in the most expeditious way possible, an idealized project delivery method combining both conventional delivery (DBB) and alternative delivery (DBOF) methods are assumed for this project.

It is assumed that the feedwater conveyance pipelines, brine discharge conveyance pipelines, product water conveyance pipelines, sub-surface intakes and dedicated concentrate outfall would be delivered under a conventional Design-Bid-Build model. It is assumed that the SWRO desalination plant would be delivered under a Design-Build-Operate-Finance model.

If the SWRO desalination plant cannot be delivered under an alternative project delivery model such as DBOF, the project implementation schedule as shown below in Table 18 would be extended by an estimated six to twelve months.

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TABLE 18 - IMPLEMENTATION SCHEDULE

Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 1st 2nd 3rd 4thProject DefinitionCEQA

NOP/ScopingTechnical Studies

Admin Draft EIRCommunity Meetings

Draft EIR45-Day Public Review

Responses to CommentsFinal EIR/District Approval

Regulatory PermitsPreliminary Engineering

Permit ApplicationsProcessing and Approvals

Prototype IntakePermitting

Marine and Seafloor TestingDesign/Procurement

ConstructionOperation

Intake/Discharge/ConveyanceDesign/Procurement

Encroachment PermittingConstruction

Desalination PlantSelect Preferred Site

Preliminary DesignProcurement

Design / ConstructionCommissioning & Start Up

2014 2015 2016 2017

« « ««

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C. NEXT STEPS

The recommended next steps for the proposed Montecito Water District Desalination Project, following the completion of this Conceptual Feasibility Study and direction from the District’s Board of Directors, are to conduct further engineering, planning, and field studies to support a Conceptual Design Report, which in turn could be considered by the Board as the basis for proceeding with the necessary environmental compliance (CEQA/NEPA) and regulatory permitting approvals for a new permanent desalination facility. The planning studies would consist of, but are not limited to, property due diligence investigations, evaluation of power options, additional conveyance alternatives, product water integration alternatives, environmental resource studies, and off-shore / on-shore geotechnical investigations. Additional technical studies will be required prior to project implementation; however, for this report only the primary next steps have been identified for District consideration. This section serves as a preliminary discussion guide for considering the immediate action items.

NOTE: for each recommendation below, the District will consider input from the October 29, 2014 Community Meeting, and continue to seek input from stakeholders at the local, state and federal level. Recommendation Nos. 6-9 should be initiated immediately, and run on a parallel path with the work efforts noted below.

RECOMMENDATIONS

1. Develop a Detailed Project Implementation Plan

Develop a detailed workplan, schedule and cost estimate to proceed through Conceptual Design Report, CEQA/NEPA compliance and regulatory permitting, taking into account input from the Community Meeting and other stakeholders, and incorporating technical, financial/funding, community outreach, project delivery, and regulatory permittting elements.

2. Identify Preferred Desalination Option(s)

This study has identified candidate desalination plant sites, as well as optional subsurface intake technologies, intake/discharge locations, and conveyance alignments. A preferred desalination project configuration, or several configurations, could be identified by the District to focus further investigations, feasibility analyses and property due diligence.

3. Initiate Desalination Technical Studies

It is critical to initiate marine, geotechnical and seafloor field studies as soon as possible to obtain information needed to further evaluate the feasibility of sub-surface intakes in the study area. In addition to these field studies, property due diligence research must be conducted to determine if the candidate intake and discharge sites identified in this conceptual feasibility study are available. Terrestrial surveys and studies should also be

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conducted to evaluate facility siting and alignment locations relative to sensitive coastal resources and consistency with applicable local, state and federal regulations, plans and policies. Other technical studies deemed appropriate to initiate early should also be conducted durin this phase, such as hydrodynamic modeling of desalination concentrate discharge, greenhouse gas emission reduction plan, and a coastal hazards analysis.

4. Prepare Conceptual Design Report

Based on the results of the above steps, prepare a Conceptual Design Report with sufficient detail to initiate the CEQA/NEPA compliance and regulatory permitting process, including adequate details on project costs, schedule, financing/fundings, and construction/delivery options.

5. Initiate Environmental and Regulatory Permitting

Utilize the Conceptual Design Report to initiate CEQA/NEPA compliance and regulatory permitting of a preferred project and/or alternatives. Community outreach and regulatory agency consultation are essential components of this process, and should be initiated early with a comprehensive plan for transparent communication, issue identification and developing proactive solutions. The CEQA/NEPA document and associated regulatory permits/approvals should provide the District with sufficient flexibility to incorporate appropriate design modifications as the project moves through the regulatory permitting, design and construction process.

6. Identify Project Delivery Method

As previously mentioned, it is assumed that this project will be delivered through a combination of conventional and alternative project delivery models. It is important that the District confirm that alternative delivery of the SWRO desalination plant is available.

7. Establish Program Management Structure

A project of this magnitude will require careful coordination of significant parallel project paths including environmental and regulatory permitting, preliminary engineering required for permitting, coordination of field studies, coordination of possible prototype intake systems, and the development of procurement documents for project implementation. Without adequate Program Management, it will be difficult to achieve the idealized project implementation schedule included in this conceptual feasibility study.

8. Financing

A project financial plan should be developed by the District to determine how this project will be financed. The District should consider researching available grant funding opportunities, low interest loans, and performing an updated Cost of Service Analysis (COSA) to evaluate impacts to the District’s rate structure.

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Conceptual Desalination Feasibility Study October 27, 2014

Page 60

With a portion of the project potentially delivered through the Design-Build-Operate-Finance model, the District must consider and evaluate how this financing alternative would impact the District’s operating budget.

9. Public Information

It is important to continually involve the District’s customers in this project as it progresses. Public relations and community outreach associated with this project have already begun and should continue throughout the duration of the project. Continuing public outreach would consist of community workshops, District mailers and website updates, and press releases.

V. CONCLUSIONS AND RECOMMENDATIONS Commensurate with the level of effort, schedule and other limitations noted herein, this Conceptual Desalination Feasibility Study finds that:

1) Desalination appears technically feasible for the Montecito Water District, in one or more combinations of intake, discharge, desalination plant and conveyance options;

2) Given the urgency of the District’s water supply situation, the District should proceed as quickly as possible with:

Recommendation 1 – Develop a Detailed Project Implementation Plan Recommendation 2 – Identify Preferred Desalination Option(s) Recommendation 3 – Initiate Desalination Technical Studies Concurrently, the District should proceed with investigating and implementing the

best solutions for Recommendations 6, 7, 8 and 9.

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Source: Esri, DigitalGlobe, GeoEye, i-cubed, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, andthe GIS User Community

Montecito Water District

Montecito Water District Service Boundary and Study AreaExhibit 1

° 0 5,000 10,0002,500Feet

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Source: Montecito Water District

Montecito Water District Service Boundary

P A C I F I C O C E A N

CARPINTERIA

CITYOF

SANTA BARBARA

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SAN YSIDRO RD

SHEFFIELD DR

ORTEGA HILL RD

N JAMESON LN

E VALLEY RD

HOT SPRINGS RD

TIBUR

ON B

AY LN

DANIELSON RD

COAST VILLAGE RD

SYCAMORE CANYON RD

OLIVE MILL RD

GREENWELL AVE

E VALLEY RD

SAN LEANDRO LN

S JAMESON LN

CHANNEL DR

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Intake Site 4 (I4)

Intake Site 5 (I5)Intake Site 1 (I1)

Intake Site 2 (I2)

Intake Site 3 (I3)

250'

500'

1000'

Montecito Water District

Seawater Intake Site AlternativesExhibit 2

° 0 2,000 4,0001,000Feet

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Distance from Shoreline

District Service Boundary

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SAN YSIDRO RD

SHEFFIELD DR

ORTEGA HILL RD

N JAMESON LN

E VALLEY RD

HOT SPRINGS RD

TIBUR

ON B

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DANIELSON RD

COAST VILLAGE RD

SYCAMORE CANYON RD

OLIVE MILL RD

E VALLEY RD

SAN LEANDRO LN

S JAMESON LN

CHANNEL DR

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Discharge Site 6 (D6)

Discharge Site 4 (D4)

Discharge Site 5 (D5)Discharge Site 1 (D1)

Discharge Site 2 (D2)

Discharge Site 3 (D3)

250'

500'

1000'

Montecito Water District

Concentrate Discharge Site AlternativesExhibit 3

° 0 2,000 4,0001,000Feet

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Distance from Shoreline

District Service Boundary

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SAN YSIDRO RD

SHEFFIELD DR

ORTEGA HILL RD

N JAMESON LN

E VALLEY RD

E VALLEY RDHOT S

PRINGS RD

SAN YSIDRO RD

TIBUR

ON B

AY LN

DANIELSON RD

COAST VILLAGE RD

SYCAMORE CANYON RD

OLIVE MILL RD

GREENWELL AVE

ASEGRA RD

E VALLEY RD

SAN LEANDRO LN

S JAMESON LN

CHANNEL DR

P8 P9P3 P10

P4P1 P5

P2

P6

P7

Montecito Water District

Candidate Desalination Plant SitesExhibit 4

° 0 2,000 4,0001,000Feet

10/2

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Desalination Plant Sites

District Service Boundary

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SAN YSIDRO RD

SHEFFIELD DR

ORTEGA HILL RD

N JAMESON LN

E VALLEY RD

E VALLEY RD

HOT SPRINGS RD

SAN YSIDRO RD

TIBUR

ON B

AY LN

DANIELSON RD

COAST VILLAGE RD

SYCAMORE CANYON RD

OLIVE MILL RD

GREENWELL AVE

ASEGRA RD

E VALLEY RD

SAN LEANDRO LN

S JAMESON LN

CHANNEL DR

P9P3 P10

P6

Montecito Water District

Candidate Desalination Plant Sites Selected for Further EvaluationExhibit 5

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Source: Montecito Water District

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Desalination Plant Sites

District Service Boundary

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Intake Site 2 and

Discharge Site 2 (I2,D2)

Discharge Site 6 (D6)

P6

Montecito Water District

Base Option System AlternativeExhibit 7

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Source: Montecito Water District

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Desalination Plant Site (P6)

Feedwater Pipeline

Brine Discharge Conveyance Pipeline - Alternative A

Brine Discharge Conveyance Pipeline - Alternative B

District Service Boundary

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Intake Site 4 and

Discharge Site 4 (I4,D4)

Discharge Site 6 (D6)

P9

Montecito Water District

Option 1 System AlternativeExhibit 8

° 0 2,000 4,0001,000Feet

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Desalination Plant Site (P9)

Product Water Pipeline

Feedwater Pipeline

Brine Discharge Conveyance Pipeline - Alternative A

Brine Discharge Conveyance Pipeline - Alternative B

District Service Boundary

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Intake Site 4 and

Discharge Site 4 (I4,D4)

Discharge Site 6 (D6)

P10

Montecito Water District

Option 2 System AlternativeExhibit 9

° 0 2,000 4,0001,000Feet

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Source: Montecito Water District

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Desalination Plant Site (P10)

Product Water Pipeline

Brine Discharge Conveyance Pipeline - Alternative B

District Service Boundary

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kjkj

Intake Site 2 and

Discharge Site 2 (I2,D2)

Discharge Site 6 (D6)

P3

Montecito Water District

Option 3 System AlternativeExhibit 10

° 0 2,000 4,0001,000Feet

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Source: Montecito Water District

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Desalination Plant Site (P3)

Product Water Pipeline

Feedwater Pipeline

Brine Discharge Conveyance Pipeline - Alternative A

Brine Discharge Conveyance Pipeline - Alternative B

District Service Boundary

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Intake Site 1 and

Discharge Site 1 (I1,D1)

Discharge Site 6 (D6)

P6

Montecito Water District

Variation of Base Option System AlternativeExhibit 11

° 0 2,000 4,0001,000Feet

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Source: Montecito Water District

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Desalination Plant Site (P6)

Feedwater Pipeline

Brine Discharge Conveyance Pipeline - Alternative A

Brine Discharge Conveyance Pipeline - Alternative B

District Service Boundary