constraints and opportunities analysis for residential...

Constraints and Opportunities Analysis for Residential Development REPORT OF PRELIMINARY RESULTS

COUNTY OF SAN LUIS OBISPO DEPARTMENT OF PLANNING & BUILDING

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Contents Introduction ............................................................................................................................................................ 1 GIS Weighted Overlay Analysis ......................................................................................................................... 2 Qualitative Analysis .............................................................................................................................................. 3 Preliminary Results .............................................................................................................................................. 3

Area No. 1 – West Paso Robles ...................................................................................................................................... 4 Area No. 2 – West Templeton ........................................................................................................................................ 6 Area No. 3 – South Atascadero ...................................................................................................................................... 8 Area No. 4 – Pozo Road Area .......................................................................................................................................... 9 Area No. 5 – Los Osos Valley Road Area .................................................................................................................. 11 Area No. 6 – Edna Valley Area ..................................................................................................................................... 12 Area No. 7 – South Arroyo Grande/North Nipomo ............................................................................................. 14 Area No. 8 – Southeast Nipomo .................................................................................................................................. 15 San Miguel Expansion Areas ........................................................................................................................................ 17 Shandon Expansion Areas ............................................................................................................................................. 17 Summary of Preliminary Results ............................................................................................................................... 20

Infill Capacity ....................................................................................................................................................... 23 Appendix A - Constraints Model .................................................................................................................... 24 Appendix B – General Plan Policies ............................................................................................................. 31

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DEPARTMENT OF PLANNING & BUILDING Constraints and Opportunities Analysis for Residential Development Report of Preliminary Results

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Introduction On June 12, 2017, the County Board of Supervisors directed staff to identify where new large tracts of land could be rezoned for residential uses. The Board’s direction specifically listed some of the criteria to be considered in this analysis including:

• Proximity to job centers and services; • Availability of infrastructure (water, wastewater, roads, etc.) and police and fire

service; • Resource availability (particularly water supply); and • Consumer preferences Other factors considered in this analysis include: agriculture, geological hazards, terrain, flood zones, fire safety, biological resources, archaeological resources, visual resources, and estimated vehicle miles traveled.

To date, staff has accomplished the following: • Evaluated existing information, including a draft mapping study from 2010 that

focused on subdivision potential and development suitability in the unincorporated rural portions of the county.

• Engaged key stakeholders (e.g., EVC, HBA, etc.) and other agencies (e.g. San Luis Obispo Council of Governments (SLOCOG)) to identify additional information needs.

• Tested and updated the 2010 Geographic Information System (GIS) model that evaluates development suitability based on factors such as: groundwater basins, agriculture, geologic hazards, biological and archaeological resources, public safety, etc.

• Prepared a preliminary permit and public facility cost analysis.

• In addition, staff has and continues to coordinate this project with SLOCOG, which is in the process of developing maps and transportation models for the 2019 Regional Transportation Plan/Sustainable Communities Strategy and Regional Housing Needs Plan.

• Staff has acquired the services of a hydrogeological consulting firm to help with refinements to the water resources mapping layer.

Contained in this report are the preliminary results from the initial constraints and opportunities analysis performed by staff. The analysis included GIS modeling, stakeholder and agency input, and staff’s qualitative evaluation of other pertinent information such as distance to job centers and services, and access to community infrastructure and public facilities. The preliminary results of this analysis presented in this report identify eight

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potential areas for new residential development. In addition, the communities of San Miguel and Shandon are discussed because each have recently had community plan updates that provide for new residential development within expansion areas. The areas identified generally have fewer constraints, when compared to other areas, and are mostly located near urban areas where greater opportunities exist. In some instances, the opportunities associated with a location can lessen the effect of a mapped constraint (e.g., access to supplemental water, or circulation improvements that reduce emergency response times and lessen vehicle miles traveled). It is important to note that these areas are generalizations with no specific properties, acreage or potential number of dwelling units identified. This report is for informational purposes only; it does not conclude if any one of the eight areas is preferred over another; and it does not include any recommendations. To initiate a project for residential development in any of these areas will require significant policy direction from the Board of Supervisors to move forward. Likewise, the County would need to conduct public outreach should a project be initiated.

GIS Weighted Overlay Analysis The GIS model was an important (and first) component in this analysis. The model utilizes the “Weighted Overlay” function within the GIS software. Weighted Overlay is a technique for applying a common measurement scale of values to diverse and dissimilar inputs to create an integrated analysis. It is akin to a standard overlay analysis where multiple layers are placed upon one another in an overlapping-layering effect. Where the various layers overlap the weights become more pronounced. The weighted overlay analysis allows values to be assigned not only to individual layers but different data within the layer itself. For instance, slopes between 0 percent and 5 percent would be valued lower (less constraining or more suitable) than slopes between 15 percent and 20 percent (more constraining or less suitable). Figure 1 illustrates this technique. In the illustration, the upper gold box is weighted at 75 percent influence and the lower gold box is weighted at 25 percent influence. When the gold boxes are overlaid, the result is the values shown in the green box. So, if the higher number were more favorable, the upper-right corner would be preferred. Please refer to Appendix A - Constraints Model for a more detailed discussion on the GIS methodology. For this analysis, 21 layers, considered to influence potential development areas, were utilized in the GIS model. The result of the model was a countywide map that shows varying degrees of constraint. From the countywide map, staff identified 48 areas on the map that

Figure 1 - Weighted Overlay Illustration

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were least constrained (or more suitable) for development. Many of the areas were too remote and removed from further consideration. Others were eliminated because the geographic area was unconsolidated, too narrow (e.g., following a stream), or the pattern was fractured (such as an area where gentle slopes where interspersed within steep topography).

Figure 2 shows an example of a constraints map where orange areas are more constrained and green areas are less constrained. A star would indicate an area that may be more suitable for future residential development because it is less constrained and near an urban area. In all, 21 of the 48 areas were evaluated further by staff, including some moderately constrained areas that were retained due to proximity to US 101 and urban infrastructure. The eight most suitable areas plus the communities San Miguel and Shandon are discussed below.

Qualitative Analysis Some of the information considered in this analysis is not characteristically compatible with the GIS model or easily mapped. Other important issues warranted further description (e.g., water, or proximity to job centers and services). In addition, factors that may be unique to an area, such as existing development patterns, potential land use conflicts, or special land forms were taken into account. Potential opportunities, such as annexation for urban service and infrastructure improvements are also included. A summary of the qualitative analysis follows the map for each of the identified areas.

Preliminary Results Staff has identified eight generalized areas that are least constrained and have greater opportunities for future residential development based on the Board of Supervisor’s direction, input from the stakeholder’s group and staff’s site-specific qualitative analysis. Following each map, the key limiting factors are listed, there is a brief description on water, proximity to jobs and services, infrastructure and public facilities, and policy considerations.

Figure 2 - Example Map

More constrained

Less constrained but remote

Exclusionary areas (gray) Less

constrained but, unconsolidated

Urban areas (gray, excluded)

Potential area for development

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A cost estimate for permits and fees for a 2,100-square foot single-family residence within each area is also included. The star located on each map signifies a generalized location and is not site specific.

Area No. 1 – West Paso Robles

Key Limiting Factors: The key limiting factors for the West Paso Robles area are water, terrain (gently rolling to steeply sloped), Agricultural (AG) zoning, intensified agriculture, oak woodland, and San Joaquin kit fox habitat. Water: The West Paso Robles area is partially located in the Paso Robles groundwater basin but mostly located over fractured rock (includes: Paso Robles Formation and granite rocks, undivided).

Proximity to Job Centers and Services: The West Paso Robles area is approximately three miles to downtown Paso Robles, three miles to US 101/13th Street in Paso Robles, 8.5 miles to US 101/Las Tables Road in Templeton, 16 miles to US 101/Santa Rosa Road in Atascadero, 31miles to Cal Poly and 31 miles to downtown San Luis Obispo. The average vehicle miles traveled (VMT) per capita per day from this area would be approximately 9 VMT.

Infrastructure and Public Facilities: This area lacks community water and wastewater systems, and drainage and circulation improvements would be required. Within Paso Robles there are public schools (K-12), public parks, and library. The nearest hospital and sheriff

U.S

. 101

Highway 46

Least Constrained

Most Constrained Exclusionary Areas

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substation are in Templeton. The nearest County fire station is approximately 6.5 miles from this area.

Policy Considerations: • The following general plan policies and principles should be considered for this area.

Please refer to Appendix B for the complete text.

o AG Element Policy 24 o Strategic Growth Principles 1 and 2 o COSE Policies: AQ 1.2, OS 4.3, and WR 1.9 o Housing Element Policies: HE 1.1, 1.2, 1.3 o Economic Element Policies: EE 3.2. and 3.3

• The cost estimate for permits and fees for a 2,100-square foot single-family residence

in this area without community water or wastewater treatment facilities is approximately $46,000.

• Prepare a Specific Plan or prepare a Public Facility Financing Plan for a community water system, wastewater treatment plant and potential circulation improvements, and rezone land for higher residential density.

• Annexation to the City of Paso Robles • Provide for the intensification of adjacent properties that are currently within the

Residential Rural and Residential Suburban land use categories.

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Area No. 2 – West Templeton

Key Limiting Factors: The key limiting factors for the West Templeton area are water, terrain (gently rolling to moderately sloped), Agricultural (AG) zoning, intensified agriculture, and agricultural preserves. Water: The West Templeton area is partially located in the Salinas Valley Atascadero Area (DRW Bulletin 118, 2016) groundwater basin but mostly located over fractured rock (includes: Paso Robles and Monterey Formations). This area is located adjacent to the Templeton Community Services District (TCSD) service boundary.

Proximity to Job Centers and Services: The West Templeton area is approximately 13 miles to US 101/13th Street in Paso Robles, two miles to US 101/Las Tables Road in Templeton, nine miles to US 101/Santa Rosa Road in Atascadero, 24.5 miles to Cal Poly and 24.5 miles to downtown San Luis Obispo. The average vehicle miles traveled (VMT) per capita per day from this area would be approximately 10 VMT.

Highway 41

Highway 46

Least Constrained


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Infrastructure and Public Facilities: This area lacks community water and wastewater systems, and drainage and circulation improvements would be required. Within Templeton there are public schools (K-12), public park, hospital, fire station and sheriff substation. The nearest library is in Paso Robles.



o AG Element Policy 24 o Strategic Growth Principles 1 and 2 o COSE Policies: AQ 1.2, SL 3.1, and WR 1.9 o Housing Element Policies: HE 1.1, 1.2, 1.3 o Economic Element Policies: EE 3.2. and 3.3


in Templeton is approximately $61,000. • Williamson Act contract cancellations • Prepare a Specific Plan, rezone land for higher residential densities, and expand the

Templeton Urban Reserve Line (URL). • Annexation to TCSD • Include intensification of adjacent properties that are currently within the URL.

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Area No. 3 – South Atascadero

Key Limiting Factors: The South Atascadero area is largely developed with suburban lots with few large undeveloped and consolidated areas for subdivisions. The area lacks a community wastewater treatment facility. Water: The South Atascadero area is served by Atascadero Mutual Water Company.

Proximity to Job Centers and Services: The South Atascadero area is approximately 11 miles to US 101/Las Tables Road in Templeton, 2.5 miles to US 101/Santa Rosa Road in Atascadero, 15 miles to Cal Poly, 15 miles to downtown San Luis Obispo, and 20 miles to San Luis Obispo Regional Airport. The average vehicle miles traveled (VMT) per capita per day from this area would be approximately 12 VMT.

Infrastructure and Public Facilities: This area lacks a community wastewater treatment facility, and drainage and circulation improvements would be required. The public elementary school is located in Santa Margarita; the public middle and high schools are located in Atascadero. Public parks and library are located in Atascadero. The nearest hospital is in Templeton. The nearest County Fire station is approximately nine miles from this area. The nearest sheriff substation is approximately 11 miles from this area.

Highway 41

Highway 58

Least Constrained


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o Strategic Growth Principle 2 o COSE Policies: AQ 1.2 and WR 1.9 o Housing Element Policies: HE 1.1, 1.2, 1.3 o Economic Element Policy: EE 3.2


in this area without a wastewater treatment facility is approximately $41,000. • Amend the Land Use Ordinance to allow accessory dwelling units (ADUs) in this area. • Prepare a public facilities financing plan for a wastewater treatment facility and

potential circulation improvements, and rezone land for higher residential densities.

Area No. 4 – Pozo Road Area

Highway 41

Least Constrained


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Key Limiting Factors: The key limiting factors for the Pozo Road area are water, access, oak woodlands, Agricultural (AG) zoning, intensive agriculture, and agricultural preserves. Water: The northerly portion of the Pozo Road area is partially located in the Salinas Valley Atascadero Area (DRW Bulletin 118, 2016) groundwater basin, and the southeasterly portion of this area is within Rinconada Valley (DRW Bulletin 118, 2016) groundwater basin. The remainder of this area is over fractured rock (includes: Atascadero, Franciscan, and Paso Robles Formations, and Santa Margarita sandstone). Proximity to Job Centers and Services: The Pozo Road area is approximately 19 miles to US 101/Las Tables Road in Templeton, 12 miles to US 101/Santa Rosa Road in Atascadero, 15 miles to Cal Poly,15 miles to downtown San Luis Obispo, and 20 miles to San Luis Obispo Regional Airport. The average vehicle miles traveled (VMT) per capita per day from this area would be greater than 13 VMT. Infrastructure and Public Facilities: This area lacks community facilities for water, wastewater treatment, and drainage and circulation improvements would be required. The public elementary school is located in Santa Margarita; the public middle and high schools are located in Atascadero. In Santa Margarita is a public park and library. The nearest hospital is in San Luis Obispo. The nearest County Fire station is approximately seven miles from this area. The nearest sheriff substation is approximately 20 miles from this area. Policy Considerations:

• The following general plan policies and principles should be considered for this area. Please refer to Appendix B for the complete text.

o AG Element Policy 24 o Strategic Growth Principles 1 and 2 o COSE Policies: AQ 1.2, OS 4.3, SL 3.1, and WR 1.9 o Housing Element Policies: HE 1.1, 1.2, 1.3 o Economic Element Policies: EE 3.2


in this area without community water or wastewater treatment facilities is approximately $41,000.

• Williamson Act contract cancellations • Prepare a Specific Plan and rezone land for higher residential densities.

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Area No. 5 – Los Osos Valley Road Area

Key Limiting Factors: The key limiting factors for the Los Osos Valley Road area are water, access, flood zone, Agricultural (AG) zoning, ag preserves, intensified agriculture, scenic resources (Morros), geology, and terrain in some areas.

Water: The southerly portion of the Los Osos Valley Road area is partially located in the San Luis Obispo Valley (DRW Bulletin 118, 2016) groundwater basin. The remainder of this area is over fractured rock (Franciscan Formation). Proximity to Job Centers and Services: The Los Osos Valley Road area is approximately three miles to Cal Poly, four miles to downtown San Luis Obispo, five miles to Highway One at Colony Drive, north of San Luis Obispo, and six miles to San Luis Obispo Regional Airport. The average vehicle miles traveled (VMT) per capita per day from this area would be approximately 7 VMT. Infrastructure and Public Facilities: This area lacks community facilities for water, wastewater treatment, and drainage and circulation improvements would be required. Within San Luis Obispo are public schools (K-12), public parks, library and hospitals. The nearest County fire station is three miles from this area and nearest sheriff substation is six miles from this area.

Least Constrained


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o AG Element Policy 24 o Strategic Growth Principles 1 and 2 o COSE Policies: AQ 1.2, SL 3.1, VR 2.1 and WR 1.9 o Housing Element Policies: HE 1.1, 1.2, 1.3 o Economic Element Policies: EE 3.2. and 3.3


in this area without community water and wastewater treatment facilities is approximately $42,000.

• Williamson Act contract cancellations • Prepare a Specific Plan or, prepare a PFFP for a community water system, wastewater

treatment plant and potential circulation improvements, and rezone land for higher residential density.

• Future annexation to the City of San Luis Obispo

Area No. 6 – Edna Valley Area

Least Constrained


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Key Limiting Factors: The key limiting factors for the Edna Valley area are access, Agricultural (AG) zoning, intensified agriculture, ag preserves, slope (in some portions), the railroad, and airport compatibility. Water: The southerly portion of this area is located in the San Luis Obispo Valley (DRW Bulletin 118, 2016) groundwater basin, the remainder of this area is over fractured rock (Franciscan formation). Proximity to Job Centers and Services: The Edna Valley area is approximately six miles to Cal Poly, five miles to downtown San Luis Obispo, eight miles to Highway One at Colony Drive, north of San Luis Obispo, three miles to San Luis Obispo Regional Airport, and 11miles to US 101/Oak Park Boulevard in the five cities area. The average vehicle miles traveled (VMT) per capita per day from this area would be approximately 11 VMT. Infrastructure and Public Facilities: This area lacks community facilities for water, wastewater treatment, and drainage and circulation improvements would be required. Within San Luis Obispo are public schools (K-12), public parks, library and hospitals. The nearest County fire station is three miles from this area and nearest sheriff substation is nine miles from this area. Policy Considerations:


o AG Element Policy 24 o Strategic Growth Principles 1 and 2 o COSE Policies: AQ 1.2, OS 4.3, SL 3.1, and WR 1.9 o Housing Element Policies: HE 1.1, 1.2, 1.3 o Economic Element Policies: EE 3.2. and 3.3


in this area without community water and wastewater treatment facilities is approximately $42,000.

• Williamson Act contract cancellations • Prepare a Specific Plan with a public facilities financing plan for a community water

system, wastewater treatment plant, circulation improvements, and potentially other facilities such as schools and parks, and rezone land for higher residential density.

• Future annexation to the City of San Luis Obispo

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Area No. 7 – South Arroyo Grande/North Nipomo

Key Limiting Factors: The key limiting factors for the South Arroyo Grande/North Nipomo area are water, access (in some areas), terrain (gently rolling to steeply sloped), oak woodlands, Agricultural (AG) zoning, ag preserves, and intensified agriculture. Water: Most of this area is located in the Nipomo Mesa Water Conservation Area of the Santa Maria groundwater basin. Some of the area is within the Nipomo Community Services District service area or sphere of influence. Proximity to Job Centers and Services: The South Arroyo Grande/North Nipomo area is approximately 21 miles to Cal Poly, 19 miles to downtown San Luis Obispo, 14 miles to San Luis Obispo Regional Airport, six miles to US 101/Oak Park Boulevard in the five cities area, and 12 miles to Santa Maria. The average vehicle miles traveled (VMT) per capita per day from this area would be approximately 12 VMT. Infrastructure and Public Facilities: Water system, wastewater system, drainage and circulation improvements would be required. Within Arroyo Grande and the Nipomo Mesa

Least Constrained


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there are public schools (K-12), public parks, hospital and library. The nearest County fire station is four miles and the nearest sheriff substation is five miles from this area. Policy Considerations:


o AG Element Policy 24 o Strategic Growth Principles 1 and 2 o COSE Policies: AQ 1.2, and SL 3.1 o Housing Element Policies: HE 1.1, 1.2, 1.3 o Economic Element Policies: EE 3.2. and 3.3


in Nipomo is approximately $59,000. • Williamson Act contract cancellations • Prepare a Specific Plan and rezone land for higher residential densities

Area No. 8 – Southeast Nipomo

Key Limiting Factors: The key limiting factors for the Southeast Nipomo area are water, Agricultural (AG) zoning, ag preserves, and terrain (gently rolling to moderate slopes).

Least Constrained


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Water: This area is located in the Santa Maria groundwater basin and a portion of the area is within the Nipomo Community Services District sphere of influence. Proximity to Job Centers and Services: The Southeast Nipomo area is approximately 26 miles to Cal Poly, 25 miles to downtown San Luis Obispo, 20 miles to San Luis Obispo Regional Airport, 11 miles to US 101/Oak Park Boulevard in the five cities area, and seven miles to Santa Maria. The average vehicle miles traveled (VMT) per capita per day from this area would be approximately 12 VMT. Infrastructure and Public Facilities: Water system, wastewater system, drainage and circulation improvements would be required. Within Nipomo and the Nipomo Mesa there are public schools (K-12), public parks, library and fire stations. The nearest hospital is seven miles and the nearest sheriff substation is 11 miles from this area. Policy Considerations:


o AG Element Policy 24 o Strategic Growth Principles 1 and 2 o COSE Policies: AQ 1.2, and SL 3.1 o Housing Element Policies: HE 1.1, 1.2, 1.3 o Economic Element Policies: EE 3.2. and 3.3


in Nipomo is approximately $59,000. • Williamson Act contract cancellations • Prepare a Specific Plan, rezone land for higher residential densities, and expand the

Nipomo Urban Reserve Line (URL). • Include intensification of adjacent properties that are currently within the URL.

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San Miguel Expansion Areas

Key Limiting Factors: The key limiting factors for the San Miguel expansion areas are cost of new infrastructure, access, railroad, Agricultural (AG) zoning, and limited local job opportunities and competition with existing job centers for attracting new businesses. Water: This area is located in the Estrella subarea of the Paso Robles groundwater basin and is served by San Miguel Community Services District. Proximity to Job Centers and Services: San Miguel is approximately 9 miles to US 101/13th Street in Paso Robles, 15 miles to US 101/Las Tables Road in Templeton, 22 miles to US 101/Santa Rosa Road in Atascadero. The average vehicle miles traveled (VMT) per capita per day from this area would be approximately 12.5 VMT.

Infrastructure and Public Facilities: Community Infrastructure improvements would be required. In San Miguel is a public school (K-8), fire station, park and library. The high school is in Paso Robles. The nearest hospital and Sheriff substation are in Templeton. Policy Considerations:


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o AG Element Policy 24 o Strategic Growth Principle 2 o COSE Policies: AQ 1.2 and SL 3.1 o Housing Element Policies: HE 1.3 o Economic Element Policies: EE 3.2 and 3.3


in San Miguel is approximately $45,000. • Approved community plan includes expansion areas. • Consider the relative impact that community buildout would have on the

groundwater basin.

Shandon Expansion Areas

Key Limiting Factors: The key limiting factors for Shandon expansion areas are cost of infrastructure, limited local job opportunities and competition with existing job centers for attracting new businesses, and distance to existing job center and services. Water: This area is located in the Shandon subarea of the Paso Robles groundwater basin and is served by County Service Area (CSA) 16. CSA-16 has an existing connection to the State Water Project pipeline. Supplemental water is required (by the Community Plan) for expansion areas. Proximity to Job Centers and Services: Shandon is 19 miles to US 101/13th Street in Paso Robles, and 26 miles to US 101/Las Tables Road in Templeton. The average vehicle miles traveled (VMT) per capita per day from this area would be greater than 13 VMT.

Highway 46

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Infrastructure and Public Facilities: Shandon lacks a community wastewater treatment, and drainage and circulation improvements would be required. In Shandon are schools (K-12), fire station, park and library. The nearest hospital and Sheriff substation are in Templeton. Policy Considerations:


o Strategic Growth Principle 2 o COSE Policies: AQ 1.2 o Housing Element Policies: HE 1.3 o Economic Element Policies: EE 3.2


in Shandon is approximately $50,000. • Approved community plan includes expansion areas. • Consider the relative impact that community buildout would have on the

groundwater basin.

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Summary of Preliminary Results West Paso Robles Key Limiting Factors: Water, terrain, ag, oak woodlands, kit fox habitat. Water: Groundwater basin and fractured rock Proximity: Approximately 9 VMT

General Plan Policies: AGP 24; SGP 1 and 2; COSE: AQ 1.2, OS 4.3, and WR 1.9; HE 1.1, 1.2 and 1.3; and EE 3.2 and 3.3 Permit/Fee Cost Estimate: $46,000 (does not include costs for community water and wastewater treatment, circulation and drainage improvements)

Infrastructure and Public Facilities: This area lacks community water and wastewater systems, and drainage and circulation improvements would be required. Within Paso Robles there are public schools (K-12), public parks, and library. The nearest hospital and sheriff substation are in Templeton. The nearest County fire station is approximately 6.5 miles from this area. West Templeton Key Limiting Factors: Water, terrain, ag Water: Groundwater basin and fractured rock Proximity: Approximately 10 VMT

General Plan Policies: AGP 24; SGP 1 and 2; COSE: AQ 1.2, SL 3.1, and WR 1.9; HE 1.1, 1.2 and 1.3; and EE 3.2 and 3.3 Permit/Fee Cost Estimate: $61,000

Infrastructure and Public Facilities: This area lacks community water and wastewater systems, and drainage and circulation improvements would be required. Within Templeton there are public schools (K-12), public park, hospital, fire station and sheriff substation. The nearest library is in Paso Robles. South Atascadero Key Limiting Factors: Largely developed, no community wastewater treatment Water: Served by AMWC Proximity: Approximately 12 VMT

General Plan Policies: SGP 2; COSE: AQ 1.2, and WR 1.9; HE 1.1, 1.2 and 1.3; and EE 3.2 Permit/Fee Cost Estimate: $41,000 (does not include costs for community wastewater treatment)

Infrastructure and Public Facilities: This area lacks a community wastewater treatment facility, and drainage and circulation improvements would be required. The public elementary school is located in Santa Margarita; the public middle and high schools are located in Atascadero. Public parks and library are located in Atascadero. The nearest hospital is in Templeton. The nearest County Fire station is approximately nine miles from this area. The nearest sheriff substation is approximately 11 miles from this area. Pozo Road Area Key Limiting Factors: Water, access, oak woodlands, ag Water: Groundwater basin and fractured rock Proximity: Greater than 13 VMT

General Plan Policies: AGP 24; SGP 1 and 2; COSE: AQ 1.2, OS 4.3, SL 3.1, and WR 1.9; HE 1.1, 1.2 and 1.3; and EE 3.2 Permit/Fee Cost Estimate: $41,000 (does not include costs for community water and wastewater treatment, circulation and drainage improvements)

Infrastructure and Public Facilities: This area lacks community facilities for water, wastewater treatment, and drainage and circulation improvements would be required. The public elementary school is located in Santa Margarita; the public middle and high schools are located in Atascadero. In Santa Margarita is a public park and library. The nearest hospital is in San Luis Obispo. The nearest County Fire station is approximately seven miles from this area. The nearest sheriff substation is approximately 20 miles from this area.

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Summary of Preliminary Results Los Osos Valley Road Area Key Limiting Factors: Water, access, flood zone, scenic resources, geology, terrain and ag Water: Groundwater basin and fractured rock Proximity: Approximately 7 VMT

General Plan Policies: AGP 24; SGP 1 and 2; COSE: AQ 1.2, SL 3.1, VR 2.1 and WR 1.9; HE 1.1, 1.2 and 1.3; and EE 3.2 and 3.3 Permit/Fee Cost Estimate: $42,000 (does not include costs for community water and wastewater treatment, circulation and drainage improvements)

Infrastructure and Public Facilities: This area lacks community facilities for water, wastewater treatment, and drainage and circulation improvements would be required. Within San Luis Obispo are public schools (K-12), public parks, library and hospitals. The nearest County fire station is three miles from this area and nearest sheriff substation is six miles from this area. Edna Valley Area Key Limiting Factors: Access, slope, railroad, ag, airport Water: Groundwater basin and fractured rock Proximity: Approximately 11 VMT

General Plan Policies: AGP 24; SGP 1 and 2; COSE: AQ 1.2, OS 4.3, SL 3.1, and WR 1.9; HE 1.1, 1.2 and 1.3; and EE 3.2 and 3.3 Permit/Fee Cost Estimate: $42,000 (does not include costs for community water and wastewater treatment, circulation and drainage improvements)

Infrastructure and Public Facilities: This area lacks community facilities for water, wastewater treatment, and drainage and circulation improvements would be required. Within San Luis Obispo are public schools (K-12), public parks, library and hospitals. The nearest County fire station is three miles from this area and nearest sheriff substation is nine miles from this area. South Arroyo Grande/North Nipomo Key Limiting Factors: Water, access, oak woodlands, ag Water: Groundwater basin and within NCSD Sphere of Influence Proximity: Approximately 12 VMT

General Plan Policies: AGP 24; SGP 1 and 2; COSE: AQ 1.2, and SL 3.2; HE 1.1, 1.2 and 1.3; and EE 3.2 and 3.3 Permit/Fee Cost Estimate: $59,000

Infrastructure and Public Facilities: Water system, wastewater system, drainage and circulation improvements would be required. Within Arroyo Grande and the Nipomo Mesa there are public schools (K-12), public parks, hospital and library. The nearest County fire station is four miles and the nearest sheriff substation is five miles from this area. Southeast Nipomo Key Limiting Factors: Water, terrain, ag Water: Groundwater basin Proximity: Greater than 12 VMT

General Plan Policies: AGP 24; SGP 1 and 2; COSE: AQ 1.2, and SL3.1; HE 1.1, 1.2 and 1.3; and EE 3.2 and 3.3 Permit/Fee Cost Estimate: $59,000

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Summary of Preliminary Results Infrastructure and Public Facilities: Water system, wastewater system, drainage and circulation improvements would be required. Within Nipomo and the Nipomo Mesa there are public schools (K-12), public parks, library and fire stations. The nearest hospital is seven miles and the nearest sheriff substation is 11 miles from this area.

San Miguel Expansion Areas Key Limiting Factors: Infrastructure costs, access, railroad, ag, jobs Water: Groundwater basin and served by SMCSD Proximity: Approximately 12.5 VMT

General Plan Policies: AGP 24; SGP 2; COSE: AQ 1.2, and SL 3.2; HE 1.1, 1.2 and 1.3; and EE 3.2 and 3.3 Permit/Fee Cost Estimate: $45,000

Infrastructure and Public Facilities: Community Infrastructure improvements would be required. In San Miguel is a public school (K-8), fire station, park and library. The high school is in Paso Robles. The nearest hospital and Sheriff substation are in Templeton. Shandon Expansion Areas Key Limiting Factors: Infrastructure cost and jobs Water: Groundwater basin and served by CSA-16 Proximity: Greater than 13 VMT

General Plan Policies: SGP 2, COSE: AQ 1.2, HE 1.3, EE 3.2 Permit/Fee Cost Estimate: $50,000

Infrastructure and Public Facilities: Shandon lacks a community wastewater treatment, and drainage and circulation improvements would be required. In Shandon are schools (K-12), fire station, park and library. The nearest hospital and Sheriff substation are in Templeton.

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Infill Capacity In addition to expansion, each of the ten urban communities have room for additional growth within existing urban reserve lines. The following table is for informational and comparative purposes only. The individual community plans, Coastal Zone area plans, the Resource Management System, and the Growth Management Ordinance should be referenced to understand community resource limitations or other factors that may affect residential development, densities or the timing of development.

Urban Community1

No. of Vacant Residential

Single-Family Parcels2

Vacant Residential Multi-Family Parcels – Cumulative Acreage

Cambria3 2,043 16.6 Cayucos 217 14.0 Los Osos 476 17.7 San Miguel 106 9.1 Shandon 32 11.8 Templeton 34 7.3 Santa Margarita 15 0 Avila Beach 0 3.2 Oceano 30 11.9 Nipomo 79 21.1 Total 3,032 112.7 Notes: 1) Does not include village reserve areas. 2) Does not include parcel zoned Residential Suburban or Residential Rural.

Does not account for parcels that may be consolidated. 3) Excludes parcels that have been retired via the Cambria Transfer of

Development Credit Program.

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Appendix A - Constraints Model This analysis was limited to rural county land. Lands that were within an incorporated City, Urban Reserve, or Village Reserve were not considered in this analysis.

Weighted Overlay The model utilizes the “Weighted Overlay” function within ESRI ArcMap (the GIS software). Weighted Overlay is a technique for applying a common measurement scale of values to diverse and dissimilar inputs to create an integrated analysis. It is akin to a standard overlay analysis where multiple layers are placed upon one another in an overlapping-layering effect. Where the various layers overlap the weights become more pronounced. The Weighted Overlay analysis allows values to be assigned not only to individual layers but different data within the layer itself. For instance, slopes between 0 percent and 5 percent would be valued lower (less constraining or more suitable) than slopes between 15 percent and 20 percent (more constraining or less suitable).

Reclassifying Data The weighted overlay requires that the data have a numeric value as an input to the model. While some layer attributes were natively numeric (slope percent for example) others contained text-based information such as “High Liquefaction Potential”. Layers with textual data required the use of the reclassify function to convert their attributes to numeric values.

Assumptions Assumptions made in the development of the Constraints model can be split into two types: data accuracy (exact mapped boundaries are often estimates) and the extent of influence (how much to weight to assign to the data for influence in the model) upon development represented by each layer. Both of these assumptions were understood and utilized by working professionals from the business community as well as by staff from various departments within the county who are intimately familiar with San Luis Obispo County, the data, and the GIS model creation and analysis process.

Determining how much weight to give individual layers and their contents took considerable time and thought. A team of County staff was assembled and met regularly to discuss the

Figure 1 - Weighted Overlay Illustration

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available data layers and their potential impacts from a variety of perspectives and possibilities. Input was sought from experts within the business community as well.

Constraints Model Layer Selection and Grouping The development of the constraints analysis began with the selection of available countywide GIS data layers which were believed to have the most impact on development potential. In an effort to ensure that all land within the County was considered and given equal analysis, countywide data coverage (See Figure 2 - Countywide coverage vs Non-Countywide Coverage) was used to the maximum extent feasible. This avoided the situation where data with a limited geographic range would skew that particular area of the County.

Utilized Constraints Data Layers The following 21 layers were considered to be influencing development and were utilized in the Constraints Model (See Figure 3 - Constraints Analysis Values and Weighting):

Ground Water Basins Agriculturally Important Soils High Value Crops Slopes between 10 and 30% Flood and Dam Inundation areas Liquefaction Landslide

Fire Potential Airport Safety Zones Emergency Response Time Fault Zones Wetlands, streams, riparian Oak Woodlands CNDDB

Kit Fox Mitigation Ratios USFWS Critical Habitat Serpentinite Formations SRA’s and ESHA’s Visually Sensitive Areas Erodibility (NRCS) Archaeological Findings

Figure 2 - Countywide Coverage vs Non-Countywide Coverage

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Constraints Model Groups

Once all layers were identified and their attributes were assigned a value it was decided that grouping the layers into 5 different categories (See Figure 3 - Constraints Analysis Values and Weighting) would allow for some additional control as to how much influence an individual layer would ultimately have.

These groups were assigned an overall value reflective of their relative constraint. As required by the weighted overlay analysis, the weight assigned to each of the five groups had to add up to 100 percent. For instance, if all five groups were valued equally they would each get 20 percent. The five group categories and their contents are listed below in order of importance.

Figure 3 - Constraints Analysis Values and Weighting

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1. Essential Data in this layer was considered essential to development. Without this resource, development could not occur. This group contains the groundwater basins layer and its respective level of severity rating which ranges from 0 (no supply issues), to 3 (severe supply issues). The essential layer is weighted at 30%.

2. Agriculture This group consists of Important Agricultural soils and areas in active crop production. The agriculture layer was developed in coordination with representatives from the Agriculture Commissioners Office and followed their recommended methodology which consisted of combined their Important Soil layer with the parcels data and valuations based on the relative area of important soils within each parcel. Parcels with Agriculture, Rural Lands, and Rural Residential were combined with the Important Soil layer so that parcels under 10 acres were removed. The remaining parcels were intersected with the Important Soil layer and parcels with greater higher-rated soil class acreage were given a higher value. Once this was completed, the Active Crop layer was added to emphasize land in active production. The Agriculture layer is weighted at 20 percent. 3. Public Safety The public safety group consists of slopes between 10 and 30 percent, flood hazard areas, dam inundation areas, liquefaction areas, landslide areas, fire hazard areas, airport safety zones, emergency response times, and earthquake faults. This group is weighted at 25 percent.

4. Protected Resources This group is made up of environmentally sensitive layers. The protected resources group consists of wetlands, riparian, streams, oak woodlands, the California Natural Diversity Database, kit fox mitigation ratios, and critical habitat areas. This group is weighted at 15 percent.

5. Other Constraints This final group consists of other constraints that were important but did not fit into any of the other established groups. It is made up of serpentine rock outcroppings, Sensitive Resource Areas and Environmentally Sensitive Habitat Areas, and visually sensitive areas as defined in the County General Plan. Other layers included are erodibility and archaeology reports with positive findings. This group is weighted at 10 percent.

Exclusionary Areas Areas of the County that were not covered by either the Constraints or Suitability models were considered to be exclusionary. The development of the exclusionary layer involved merging the relevant topics together, dissolving them, and adding it as an overlay to the final

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map. The final list of eight exclusionary layers was utilized in both the Constraints and Suitability models. The following data layers make up the exclusionary group:

Open Space Urban boundaries (Cities, URL, VRL)

Public Land Water bodies Conservation Easements

Slopes > 30%

Airport Safety Zones Alquist-Priolo Fault Zones

Interpreting the Results

It is important to bear in mind that there are layers represented in the analysis that do not cover the entire County and there are other layers that were used whose data is considered “reference quality” meaning that these layers are better suited for larger scale viewing such as in a Statewide analysis. It is important to keep that in mind when viewing down to a scale of a single property so that it is understood that the data may not reflect actual ground conditions. That being said, the County Planning Department feels that the mapping is accurate enough to yield a good idea of what can be expected for larger areas such as areas surrounding an Urban Reserve Line (URL).

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GIS Methodology – Appendix Tools Used in the Constraints Model The Constraints and Suitability models were developed using 5 primary tools: Select, Union, Polygon to Raster, Reclassify, and Weighted Overlay.

Select - Allows for the selection of desired attributes

Union – Used to combine layers with the county boundary to ensure total coverage.

Polygon to Raster – Used to convert polygon type data to a cell (pixel) based image.

Reclassify - Assigns numeric values in place of text based attributes.

Weighted Overlay - Overlays several rasters using a common measurement scale and weights each according to its importance.

The process for creating the weighted overlay required the initial selection of relevant attributes using the select tool. The selection of attributes such as “Very High” and “High” while ignoring “Low” allows for the identification of only those areas which will have the most significant impact on development constraints. Once these specific attributes were selected, they were combined with the County boundary layer using the union operation to create a layer that had complete county coverage. This layer is then converted to a raster with the polygon to raster conversion tool.

Figure A4 - Complete constraints model

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Numeric values ranging between 1 and 10 were then assigned to each cell replacing the text based attributes using the reclassify tool. Areas which are not covered by an attribute of interest were given a value of 0 to negate impact on the final map.

After all the layers were converted to rasters and values assigned they were entered into the weighted overlay process. This process actually takes place twice. First, the layers identified in each of the 5 groups were overlaid in an initial weighted overlay process creating an output for each of the five groups (Essential, Agriculture, Public Safety, Protected Resources, and Other). Then the five resulting outputs were weighted again in the final overlay process (See Figure 3 - Constraints Analysis Values and Weighting for grouping and rankings, and for the output).

The output of the final weighted overlay analysis is an image which has values assigned for each cell, taking the relative weights into account. Ranges of values were decided upon for each level of constraint, ranging from 1 (least constrained) to 5 (most constrained). The final graphic representation can be easily read to identify the level of constraint within each area based on the color variation.

Figure A5 - Initial model steps

Figure A6 - Reclassification and Weighted Overlay

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Appendix B – General Plan Policies

The General Plan provides policies for planning land uses and for allowing new development. The San Luis Obispo County General Plan contains 11 elements in nine separate documents (Land Use and Circulation, Housing, Conservation and Open Space, Noise, Safety, Agriculture, Economic, Off Shore Energy, and Parks and Recreation). This appendix lists 13 (key) general plan policies (and principles) that should be considered when making determinations for residential expansion. For each of the areas identified in this report, the applicable policies for that area are listed in the respective sections of this report. It is important to note that only the key policies, for this analysis, are listed below. Should a future land use project (such as a specific plan) be initiated, as a result of this report, that project would need to be found consistent with the County General Plan, as a whole, which would likely involve analyses and discussion on several General Plan policies in addition to the following.

Agriculture Element

AG Policy 24 - Conversion of Agricultural Land

Discourage the conversion of agricultural lands to non-agricultural uses through the following actions:

1. Work in cooperation with the incorporated cities, service districts, school districts, the County Department of Agriculture, the Agricultural Advisory Liaison Board, Farm Bureau, and affected community advisory groups to establish urban service and urban reserve lines and village reserve lines that will protect agricultural land and will stabilize agriculture at the urban fringe.

2. Establish clear criteria in this plan and the Land Use Element for changing the designation of land from Agriculture to non-agricultural designations.

3. Avoid land redesignation (rezoning) that would create new rural residential development outside the urban and village reserve lines.

4. Avoid locating new public facilities outside urban and village reserve lines unless they serve a rural function or there is no feasible alternative location within the urban and village reserve lines.

Land Use and Circulation Element

Strategic Growth Principle 1 - Preserve open space, scenic natural beauty and sensitive environmental areas. Conserve energy resources. Conserve agricultural resources and protect agricultural land.

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Strategic Growth Principle 2- Strengthen and direct development towards existing and strategically planned communities.

Conservation and Open Space Element

COSE Policy AQ 1.2 Reduce vehicle miles traveled

COSE Policy OS 4.3 Conversion of rural areas to Urban Lands

COSE Policy SL 3.1 Conserve Important Agricultural Soils

COSE Policy VR 2.1 Develop in a manner compatible with Historical and Visual Resources

COSE Policy WR 1.9 Discourage new water systems

Housing Element

HE 1.1: Designate a sufficient supply of land for housing that will facilitate balanced communities, including a variety of housing types, tenure, price, and neighborhood character.

HE 1.2: Plan for future housing needs beyond the State-required planning period (2009-2014) for this Housing Element. This is important because the tasks necessary to identify land for housing and provide infrastructure can take several years to accomplish.

HE 1.3: Designate land for housing near locations of employment, shopping, schools, parks, and transportation systems when feasible.

Economic Element

Policy EE 3.2: Foster development that is compact and in reasonable proximity to necessary infrastructure and existing development.

Policy EE 3.3: Work closely with cities and community services districts to provide continuity of land use planning and to achieve a balance between economic and housing growth and services.

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constraints and opportunities analysis for residential...

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