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City of Los Angeles IV.G-1 Loyola Marymount University Master Plan Project Draft EIRENV-2008-1342-EIR January 2010
IV.G SURFACE WATER HYDROLOGY AND WATER QUALITY
1.0 INTRODUCTION
This section describes the potential impacts of the Proposed Project on surface water hydrology and
surface water quality on the Loyola Marymount University (LMU) campus and in the surrounding area.
This section incorporates and summarizes information contained in the Surface Water Hydrology and
Water Quality Analysis prepared by KPFF Consulting Engineers, dated July 2009. A copy of the report is
provided in Appendix IV.G.
2.0 REGULATORY SETTING
2.1. Hydrology and Drainage
2.1.1 Federal Regulations
2.1.1.1 National Flood Insurance Act
The National Flood Insurance Act established the National Flood Insurance Program, which is based on
the minimal requirements for flood plain management and is designed to minimize flood damage within
Special Flood Hazard Areas. According to the Federal Emergency Management Agency Flood Insurance
Rate Map, the entire campus is in an area of minimal flooding (Flood Zone C) and does not require flood
insurance.1
2.1.2 Local Level
Drainage and flood control structures and improvements in the City of Los Angeles are subject to review
and approval by the City of Los Angeles, Bureau of Engineering. Storm drains within the City are
constructed by both the City and the Los Angeles County Flood Control District. The Los Angeles County
Flood Control District constructs the major storm drains and open flood control channels, and the City
constructs local interconnecting tributary drains. The City designs its systems to convey storm flows from
1 KPFF Consulting Engineers, LMU Surface Water Hydrology and Water Quality Analysis, (2009), 5. (Provided inAppendix IV.G.) Flood Zone C is identified in the community Flood Insurance Study as an area of minimalhazard from the principal source of flood in the area. However, buildings in Flood Zone C could be flooded bysevere, concentrated rainfall coupled with inadequate local drainage systems. Local stormwater drainagesystems are not normally considered in the community's Flood Insurance Study. Source: Federal EmergencyManagement Agency, Answers to Questions about the NFIP, http://www.fema.gov/business/nfip/fhamr.shtm#79.2009.
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a 10-year storm event, while the County designs for a 50-year storm event and the federal government
(Army Corps of Engineers) designs for a 100-year event.2
The County of Los Angeles and the City of Los Angeles are co-permittees under the municipal
stormwater National Pollutant Discharge Elimination System permit for Los Angeles County (also
known as the MS4 permit), which is discussed further below under the Federal Clean Water Act
regulations.3 In order to comply with the National Pollutant Discharge Elimination System Program, a
Standard Urban Storm Water Mitigation Plan is required to address stormwater pollution from new
construction and redevelopment projects.4 Although most of the Best Management Practices identified in
the Standard Urban Storm Water Mitigation Plan focuses on water quality issues such as the infiltration
or treatment of stormwater runoff and reduction of the post-project discharge of pollutants from
stormwater conveyance systems, one structural Best Management Practice requires that a project control
peak flow discharge to provide stream channel and over bank flood protection.5 The Proposed Project is
required to incorporate appropriate Standard Urban Storm Water Mitigation Plan requirements into
project plans as part of the development plan approval process for building and grading permits.6
Drainage and flood control structures and improvements in the City of Los Angeles are subject to review
and approval by the City of Los Angeles Department of Public Works and Department of Building and
Safety.7 As required by the City of Los Angeles Department of Public Works, all public storm facilities
must be designed in conformity with the standards set forth by Los Angeles County. The City of Los
Angeles Department of Public Works reviews and approves storm drain plans prior to construction.8
2 City of Los Angeles, Los Angeles Citywide General Plan Framework Final EIR, (1995), 2.8-4.3 City of Los Angeles, Department of Public Works, Bureau of Sanitation, Watershed Protection Division,
Development Best Management Practices Handbook, Part A – Construction Activities, Third Edition (2004).4 Los Angeles County Department of Public Works, Development Planning for Storm Water Management: A
Manual for the Standard Urban Storm Water Mitigation Plan, (2002), 1-2 and 1-3.5 City of Los Angeles, Department of Public Works, Bureau of Sanitation, Watershed Protection Division,
Development Best Management Practices Handbook, Part A – Construction Activities.6 LAMC, Section 64.70 et seq., (Ordinance No. 172,176); LAMC, Chapter IX, Section 70.7 LAMC Section 64.70.02. Pollutant Discharge Control, Subsection D; LAMC Section 64.72.01. Authority of the
Board of Public Works.8 LAMC Section 64.72.01. Authority of the Board of Public Works.
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2.2 Surface Water Quality
2.2.1 Federal Regulations
2.2.1.1 Clean Water Act
The Federal Water Pollution Control Act was established in 1948 and substantially expanded in 1972, at
which time it became commonly known as the Clean Water Act. The 1972 amendments established the
National Pollutant Discharge Elimination System (NPDES) program and made procurement of a permit
for the point source discharge of pollutants to waters of the United States a requirement.9 The Water
Quality Act of 1987 added Section 402(p) to the Clean Water Act, which directed the United States
Environmental Protection Agency to establish requirements for stormwater discharges from municipal
and industrial sources.10 In response to the 1987 amendment, Phase I of the United States Environmental
Protection Agency National Pollutant Discharge Elimination System Program required National
Pollutant Discharge Elimination System permits for (1) municipal separate storm sewer systems generally
serving, or located in, incorporated cities with 100,000 or more people (referred to as MS4 permits);
(2) 11 specific categories of industrial activity (including landfills); and (3) construction activity that
disturbs 5 acres or greater of land.11 In March 2003, Phase II of the National Pollutant Discharge
Elimination System Program extended requirements for National Pollutant Discharge Elimination System
permits to (1) numerous small municipal separate storm sewer systems, (2) construction sites of 1 to
5 acres, and (3) industrial facilities owned or operated by small municipal separate storm sewer systems,
which were previously exempted from stormwater permitting.
Section 402 (p) of the Clean Water Act mandates that the MS4 permits12 must (1) effectively prohibit the
discharges of non-stormwater to the stormwater system except under certain provisions; and (2) require
controls to reduce pollutants in discharges from the stormwater system to the maximum extent
practicable, including best management practices, control techniques, and system, design, and
engineering methods.13
9 U.S. Environmental Protection Agency. History: Water, http://www.epa.gov/history/topics/fwpca/05.htm. (2009).10 County of Los Angeles, Municipal Storm Water Permit (NPDES No. CAS004001, Order No. 01-182).11 U.S. Environmental Protection Agency. Amendments to the National Pollutant Discharge Elimination System
(NPDES) Regulations for Storm Water Discharges Associated With Oil and Gas Exploration, Production, Processing, orTreatment Operations, or Transmission Facilities, available at http://cfpub.epa.gov/NPDES/stormwater/oilgas.cfm.2006.
12 U.S. Environmental Protection Agency. Clean Water Act, Section 402: National Pollutant Discharge EliminationSystem. http://www.epa.gov/owow/wetlands/laws/section402.html. 2009.
13 U.S. Environmental Protection Agency. Clean Water Act, Section 402.
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A MS4 permit was issued to the County of Los Angeles and 84 incorporated cities (with the exception of
the City of Long Beach) in December 2001.14 To meet the Los Angeles County MS4 Permit requirements,
municipalities are required to implement the Storm Water Quality Management Program that was
prepared as part of the Report of Waste Discharge filed as part of the National Pollutant Discharge
Elimination System approval process. Pursuant to this program, municipalities, including the City of Los
Angeles, are required to conduct a variety of activities including, but not limited to, the following:
Control discharges at commercial/industrial facilities through tracking, inspecting, and ensuringcompliance at facilities that are critical sources of pollutants;
Implement a development planning program for specified development projects;
Implement a program to control construction runoff from construction activity at all constructionsites within its jurisdiction; and
Implement a public agency activities program.
The National Pollutant Discharge Elimination System (NPDES) General Permit for Storm Water
Discharges from Construction Activities requires that all developers of land where construction activities
will occur on 1 acre or greater do the following:
Eliminate or reduce non-stormwater discharges to storm sewer systems and other waters of theUS;
Develop and implement a Storm Water Pollution Prevention Plan, which specifies BestManagement Practices that will reduce pollution in stormwater discharges to the Best AvailableTechnology Economically Achievable/Best Conventional Pollutant Control Technologystandards; and
Perform inspections and maintenance of all Best Management Practices.15
In order to obtain coverage under the National Pollutant Discharge Elimination System General
Construction Permit, a project applicant must submit a Notice of Intent to the State Water Resources
Control Board and prepare a Storm Water Pollution Prevention Plan. Best Management Practices within
the Storm Water Pollution Prevention Plan typically regard minimization of erosion during construction,
stabilization of construction areas, sediment control, control of pollutants from construction materials, as
well as post-construction stormwater management (e.g., the minimization of impervious surfaces,
14 County of Los Angeles Municipal Storm Water Permit (National Pollutant Discharge Elimination System No.CAS004001, Order No 01-182).
15 U.S. Environmental Protection Agency. National Pollutant Discharge Elimination System (NPDES) General Permit forStormwater Discharges from Construction Activities – Fact Sheet, http://cfpub.epa.gov/NPDES/stormwater/const.cfm.2009.
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treatment of stormwater runoff, etc). The Storm Water Pollution Prevention Plan also must include a
discussion of the program to inspect and maintain all Best Management Practices.16
The City of Los Angeles Development Best Management Practices Handbook, Part A Construction
Activities, 3rd Edition, adopted by the City of Los Angeles Board of Public Works on September 29, 2004,
and associated ordinances also have specific minimum Best Management Practice requirements for all
construction activities and require that construction projects with 1 acre or greater of disturbed soil
require the preparation of a Storm Water Pollution Prevention Plan and filing of a Notice of Intent to
comply with the State National Pollutant Discharge Elimination System General Construction Permit
with the State Water Resources Control Board.17
The City of Los Angeles Development Best Management Practices Handbook also address water quality
associated with project operations.18 However the Initial Study determined that the Proposed Project
would not have long-term water quality impacts or violate water quality standards or waste discharge
requirements.
2.2.2 State Regulations
2.2.2.1 Porter-Cologne Water Quality Control Act
The Porter-Cologne Water Quality Control Act of 1969 established the principal state program for water
quality control.19 The Porter-Cologne Water Quality Control Act20 also authorizes the State Water
Resources Control Board to implement the provisions of the Federal Clean Water Act. The Act divided
the state into nine Regional Water Quality Control Board areas. Each Regional Water Quality Control
Board implements and enforces provisions of the Porter-Cologne Act and the Clean Water Act subject to
policy guidance and review by the State Water Resources Control Board. The Proposed Project site is
located in Region 4, the Los Angeles Regional Water Quality Control Board area.
Section 13050 of the Porter-Cologne Water Quality Control Act defines pollution, contamination, or
nuisance. Pollution is an alteration of the water quality such that it unreasonably affects the water’s
16 U.S. Environmental Protection Agency. National Pollutant Discharge Elimination System (NPDES) General Permit forStormwater Discharges from Construction Activities – Fact Sheet.
17 City of Los Angeles, Department of Public Works, Bureau of Sanitation, Watershed Protection Division,Development Best Management Practices Handbook , Part A – Construction Activities .
18 City of Los Angeles, Department of Public Works, Bureau of Sanitation, Watershed Protection Division,Development Best Management Practices Handbook, Part A – Construction Activities.
19 State Water Resources Control Board. Porter-Cologne Water Quality Control Act with Additions and AmendmentsEffective January 1, 2009. http://www.waterboards.ca.gov/laws_regulations/docs/portercologne.pdf. 2009.
20 California Water Code, Division 7. Water Quality.
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beneficial uses; contamination is an impairment of the water quality to the degree that it creates a hazard
to public health; and a nuisance is anything that is injurious to health, is offensive to the senses, or is an
obstruction to property use, and which affects a considerable number of people.21
2.2.2.2 Storm Water Pollution Prevention Plan
For “projects that disturb one or more acres of soil or projects that are less than 1 acre but are part of a
larger common plan of development that in total disturbs one or more acres,” the California State Water
Resources Control Board requires that a Stormwater Pollution Prevention Plan be developed and
implemented for the construction of the project.22
A Storm Water Pollution Prevention Plan defines “best management practices” to protect stormwater
runoff from carrying sediment and/or pollutants to areas off of the construction site and causing erosion
problems.23 Best management practices can include, but are not limited to, sandbag barriers, stabilized
construction entrances, street sweeping, inlet protection, and any other practices deemed necessary at the
time of construction.24
The California General Construction Activity Storm Water Permit, adopted by the State Water Resources
Control Board, regulates construction activity including clearing, grading, and excavation resulting in soil
disturbance of at least 1 acre of land area.25 This General Permit authorizes the discharge of stormwater
to surface waters from construction activities. It prohibits the discharge of materials other than
stormwater and authorized non-stormwater discharges and all discharges that contain a hazardous
substance in excess of reportable quantities established at 40 Code of Federal Regulations 117.3 or
40 Code of Federal Regulations 302.4, unless a separate National Pollutant Discharge Elimination System
Permit has been issued to regulate those discharges.
21 State Water Resources Control Board. Porter-Cologne Water Quality Control Act with Additions and AmendmentsEffective January 1, 2009, Chapter 2. Definitions, § 13050. Definitions (l)(1),http://www.waterboards.ca.gov/laws_regulations/docs/portercologne.pdf. 2009.
22 State Water Resources Control Board, Storm Water Program: Construction Storm Water Program,http://www.swrcb.ca.gov/water_issues/programs/stormwater/construction.shtml. 2009.
23 State Water Resources Control Board, Storm Water Program: Construction Storm Water Program.24 City of Los Angeles, Department of Public Works, Bureau of Sanitation, Watershed Protection Division,
Development Best Management Practices Handbook, Part A: Construction Activities.25 State Water Resources Control Board, National Pollutant Discharge Elimination System (NPDES) General Permit
for Storm Water Discharges Associated with Construction Activity (NPDES No. CAS000002).
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2.2.3 Local Regulations
In accordance with the Porter-Cologne Water Quality Control Act and the Clean Water Act Amendments
of 1972, the Los Angeles Regional Water Quality Control Board established a Water Quality Control Plan
for the Los Angeles Region, known as the Basin Plan.26 The Basin Plan designates beneficial uses of water
bodies, sets water quality objectives to protect those uses, addresses localized water quality problems,
and sets forth a plan to protect water quality. General discharge permits issued by the Los Angeles
Regional Water Quality Control Board under the Basin Plan are used to regulate polluted stormwater
runoff, treated groundwater, non-hazardous soil disposal, and other discharges.27
In accordance with the Los Angeles County MS4 Permit requirements, the City of Los Angeles has
developed and completed several programs and activities, including the adoption of ordinances relating
to stormwater regulation and completion of a Development Best Management Practices Handbook (3rd
Edition) governing construction and planning activities.
2.2.3.1 Standard Urban Storm Water Mitigation Plan
Under recent regulations adopted by the Los Angeles Regional Water Quality Control Board, projects are
required to implement a Standard Urban Storm Water Mitigation Plan during the operational life of the
Project to ensure that stormwater quantity and quality is addressed by incorporating best management
practices into the design of the project. This plan defines water quality design standards to ensure that
stormwater runoff is managed for water quality concerns and to ensure that pollutants carried by
stormwater are confined and not delivered to waterways. Project applicants are required to abide by
source control and treatment control best management practices from the list approved by the Los
Angeles Regional Water Quality Control Board and included in the Standard Urban Storm Water
Mitigation Plan. These measures include infiltration of the stormwater into the ground as well as filtering
runoff before it leaves a site. This can be accomplished through various means, including the use of
infiltration pits, flow-through planter boxes, hydrodynamic separators, and catch basin filters.
In combination, these treatment control best management practices must be sufficiently designed and
constructed to treat or filter the first 0.75 inch of stormwater runoff from a 24-hour storm event.
Post-development runoff rates and volumes cannot exceed runoff rates and volumes of pre–development
conditions, and treatment systems must be constructed or installed to treat runoff from the first 0.75 inch
of rainfall for projects within a Standard Urban Storm Water Mitigation Plan category.
26 Los Angeles Regional Water Quality Control Board. Water Quality Control Plan: Los Angeles Region, (1995).27 Los Angeles Regional Water Quality Control Board. Water Quality Control Plan: Los Angeles Region.
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3.0 EXISTING CONDITIONS
3.1 Existing Surface Water Hydrology Conditions
3.1.1 Topography
The LMU campus varies in elevation from approximately 66 feet above mean sea level at the primary
entrance to the campus, at LMU Drive entrance and Lincoln Boulevard, to approximately 120 feet at the
northeast corner of Burns Campus, to 150 feet in the campus interior. The campus rises above the
adjacent Ballona Plain, with the majority of the elevation difference evident on Hughes and Leavey
Campuses. Burns Campus slopes gently downhill from south to north as it approaches the bluff edge
along the northern campus boundary.
3.1.2 General Campus Hydrology
For purposes of stormwater runoff, the LMU campus comprises three distinct watersheds or drainage
areas. The first watershed generally encompasses the southeast corner of Burns Campus, including
Sullivan Field, the baseball and softball fields, the tennis courts, and the area north of the tennis courts.
This watershed discharges into the McConnell Avenue Storm Drain at the southeast corner of Burns
Campus. The second watershed encompasses the remainder of Burns Campus, which discharges into the
riparian corridor at the northeast corner of Burns Campus. The third watershed encompasses all of
Hughes and Leavey and discharges into the riparian corridor west of Hughes Campus.
3.1.2.1 Surface Permeability
Existing impervious surface area (i.e., developed or paved area) campus totals approximately 88 acres, or
62 percent of the total 142-acre campus area, and is comprised of roads, walkways, and residential,
academic, administrative, and athletic facilities. The remaining 54 acres, or 38 percent, of the campus are
pervious surfaces where water can directly percolate into the soil, including lawns, athletic fields, a
stormwater collection and flood control sump, and landscaped areas.
3.1.2.2 Stormwater Drainage Facilities and Surface Runoff Flow Direction on Campus
The Hydrology Study prepared by KPFF Consulting Engineers, included as Appendix IV.G addresses
Burns, Leavey, and Hughes Campuses separately, because these areas were developed at different times
and have distinct, though interrelated, hydrological characteristics. Therefore, the Draft EIR discusses
existing hydrological conditions for each of these three hydrological areas. Stormwater runoff from the
campus is conveyed by a non-erosive storm drain system consisting of area drains, catch basins, gutters,
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roof drains, and storm drain piping. These systems convey runoff from the campus to the Santa Monica
Bay. The existing storm drain system is shown in Figure IV.G-1, Existing Storm Drains.
Burns Campus
The majority of stormwater on Burns Campus is conveyed to the north through a LMU-owned storm
drain lines ranging from smaller polyvinyl chloride laterals to larger reinforced-concrete pipe mains that
eventually flows into a 66-inch diameter City of Los Angeles reinforced-concrete pipe storm drain in the
northeast corner of the campus, which in turn flows into the riparian corridor at the base of the bluffs on
the Playa Vista site. The capacity of this storm drain is unknown.
During larger storm events (beyond the 10-year event), the Sunken Garden, in the northern center of
Burns Campus can act as a retention and flood control area. The 24-inch LMU-owned storm drain leaving
the Sunken Garden and directing flows to the riparian corridor handles stormwater runoff that is in
excess of its design capacity during storm events at and beyond the 10-year event.28 This causes the
stormwater to back up in the pipe and surcharge out of the existing catch basins along the pipe. These
catch basins are located in the Sunken Garden, causing the Sunken Garden to fill up with stormwater and
act as a retention pond during heavy storm events.
Furthermore, the 12-inch storm drain to the east of the Sunken Garden that connects to the Sunken
Garden outflow storm drain and the 8-inch and 12-inch storm drains at the southwest corner of Burns
Campus that leads to the Sunken Garden are currently above capacity.
Stormwater flow from the southeast corner of Burns Campus is conveyed to an existing 24-inch
reinforced-concrete pipe storm drain and then flows to the south under the softball and baseball fields
where the stormwater flow is discharged off campus into the 36-inch diameter City of Los Angeles
reinforced concrete pipe storm drain called the McConnell Avenue Storm Drain. The 24-inch storm drain
has adequate capacity for current conditions, and the 36-inch storm drain has excess capacity. This storm
drain is currently operating below capacity and there are no known flooding issues in this area of
campus.
Leavey Campus
Runoff on Leavey Campus is collected and conveyed to the south through an LMU-owned 27-inch
diameter reinforced-concrete pipe storm drain line in LMU Drive. Prior to exiting the campus, flows from
the north side of Leavey Campus and the William H. Hannon Library enter a junction box, where low
28 KPFF Consulting Engineers, LMU Surface Water Hydrology and Water Quality Analysis, (2009).
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flow storm event and irrigation runoff are diverted into an approximately 27,000 cubic feet sump located
near Drollinger Parking Plaza.
This sump has an area of 3,600 feet and an average depth of 7.5 feet and was designed to treat and store
runoff in accordance with the National Pollutant Discharge Elimination System Permit, which requires
the “first flush” of stormwater runoff (equivalent to a 2-year storm event) to be treated prior to exiting the
campus. During heavier storms, the overflow continues through the junction box in the 27-inch diameter
LMU-owned and maintained reinforced concrete pipe that becomes a City of Los Angeles storm drain
main prior to exiting Leavey Campus and entering Hughes Campus. The portion of this storm drain at
the south end of Leavey Campus that travels east to west in LMU Drive is City-owned and maintained,
and has adequate capacity for current flow volumes. There are no known flooding issues in this area of
campus and this storm facility is currently operating below capacity.
Hughes Campus
After entering Hughes Campus from the north, the 27-inch City-owned storm drain increases in diameter
to a 33-inch storm drain and continues south under LMU Drive. A City-owned and maintained 24-inch
reinforced concrete pipe storm drain is also present at the south side of University Hall which flows to
the west and then joins the storm drain main in LMU Drive. The main, which currently operates below
capacity, then exits the campus on the west side of LMU Drive and directs flows into the riparian corridor
through a 36-inch reinforced concrete pipe storm drain.
3.1.3 Stormwater Conveyance and Treatment Systems
3.1.3.1 Riparian Corridor
As part of implementation of the Playa Vista Project, the Centinela Ditch was replaced with the riparian
corridor. The riparian corridor is a shallowly sloped, naturally vegetated stormwater conveyance and
flood control channel, varying in width from 5 feet to 90 feet, that provides surface water runoff
treatment in the form of sedimentation, biofiltration, bacterial reduction and decomposition, and plant
uptake. It is planted with cattails and other vegetation on the channel bottom and willows along the side
slopes. Stormwater runoff inside the riparian corridor may contain pollutants from contributing urban
areas including sediment, nutrients, pesticides, construction waste, and other miscellaneous waste.
Existing Storm Drains
FIGURE IV.G-1
877-002•06/09
SOURCE: KPFF Consulting Engineers, LMU Surface Water Hydrology and Water Quality Analysis - June 2009.
APPROXIMATE SCALE IN FEET
400 200 0 400
n
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The riparian corridor is designed to treat and remove these pollutants from the runoff prior to emptying
into the freshwater marsh and, downstream, the Ballona Wetlands.
The freshwater marsh is located west of Lincoln Boulevard, across the street from Playa Vista. Runoff
from the freshwater marsh travels through the Ballona Wetlands to the Ballona Channel which eventually
empties into the Pacific Ocean. The marsh was also constructed as part of the Playa Vista Project to
control the amount of runoff, and concentration of pollutants carried by this runoff, flowing into the
Ballona Wetlands.
Approximately 85 percent of the LMU campus is part of the tributary (drainage) area of the riparian
corridor. This includes Leavey Campus, Hughes Campus, and all of Burns Campus except the southeast
portion, which drains to the McConnell Avenue Storm Drain. As discussed above, flows from Burns
Campus into the tiparian corridor exceed the capacity of the storm drain.
3.1.4.2 McConnell Avenue Storm Drain
The McConnell Avenue Storm Drain collects stormwater runoff from the surrounding urban area. The
stormwater runoff in the southeast portion of Burns Campus is collected in a 36-inch City of Los Angeles
reinforced concrete pipe storm drain through a catch basin located in 80th Street. This runoff empties into
the 36-inch McConnell Avenue Storm Drain, which is maintained by the Los Angeles County Flood
Control District. The McConnell Avenue Storm Drain continues south toward Los Angeles International
Airport within the Lincoln Boulevard alignment and then west to the Pacific Ocean via the City of Los
Angeles and County of Los Angeles storm drain systems. Stormwater from the McConnell Avenue Storm
Drain does not enter Ballona Creek or the Riparian Corridor west of the LMU campus at any point.
Currently, the McConnell Avenue Storm Drain has excess capacity.
3.1.4 Los Angeles Department of Public Works Flood Control Easements
According to available record information from the Los Angeles Department of Public Works,29 three
City storm drain easements are present on the LMU campus. A 10-foot storm drain easement is present
on the south side of Hughes Campus, extending from the Campion Drive cul-de-sac around the south
side of University Hall to LMU Drive, and contains a 24-inch reinforced concrete pipe storm drain.
Another 10-foot storm drain easement runs along the north side of Hughes Campus from the intersection
of Altavan Avenue and W. 78th Street to LMU Drive, and also contains a 24-inch reinforced concrete pipe
storm drain. A third easement in the northeast corner of the portion of Burns Campus varies from 10 to
29 City of Los Angeles, Department of Public Works, http://navigatela.lacity.org/index.cfm. 2009.
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15 feet in width, connecting McConnell Avenue to the riparian corridor,30 and contains a 66-inch
reinforced concrete pipe storm drain.
3.1.5 Flood Zone Characteristics
According to the Federal Emergency Management Agency Flood Insurance Rate Map, the entire campus
is in an area of minimal flooding (Flood Zone C).31
3.2 Existing Surface Water Quality Conditions
3.2.1 Potential Sources of Erosion, Sedimentation, and Pollution
3.2.1.1 Erosion and Sedimentation
The LMU campus includes steep hillside areas and bluffs along its northwest side. This area could be a
potential source of erosion and sedimentation if stormwater runoff from the campus were allowed to
sheet or channel flow uncontrolled over the hillside into the riparian corridor. Currently, this is controlled
by collecting stormwater runoff in a series of catch basins and area drains prior to the runoff flowing over
the hillside.
3.2.1.2 Pollution
The LMU campus contains approximately 54 acres of pervious area, or 38 percent of the campus, much of
which is planted with grass and/or miscellaneous vegetation. These areas may use pesticides and/or
fertilizers, which can be a source of pollution if carried off-campus by stormwater runoff.
The remaining impervious areas of the campus consist of roof areas, driveway parking lot areas, and
miscellaneous hardscape, such as walkways and the pool deck. All impervious surface areas collect dust
and particulate matter that are conveyed to the stormwater drainage facilities by stormwater runoff. In
addition, driveways and parking lot areas collect oil and grease deposits and brake dust from
automobiles; the deposits and dust can get washed into the existing catch basins.
30 The riparian corridor is located at the base of the Westchester Bluffs along the north edge of campus and servesas a form of water retention and treatment. More information is provided in Section 3.1.3.1.
31 Flood Zone C is identified in the community Flood Insurance Study as an area of minimal hazard from theprincipal source of flood in the area. However, buildings in Flood Zone C could be flooded by severe,concentrated rainfall coupled with inadequate local drainage systems. Local stormwater drainage systems arenot normally considered in the community's Flood Insurance Study. Source: Federal Emergency ManagementAgency, Answers to Questions about the NFIP, http://www.fema.gov/business/nfip/fhamr.shtm#79, April 2, 2009.
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3.2.2 Measures to Control Erosion, Sedimentation and Pollution
Sump
Stormwater runoff from Leavey Campus drains into a sump west of the Drollinger Parking Plaza. This
sump was designed to treat and store runoff for the National Pollutant Discharge Elimination System
(NPDES) permit, which requires the first 0.75 of an inch of stormwater runoff for sediment and pollutant
removal prior to leaving the campus.
Currently, this translates to a required sump volume of approximately 13,000 cubic feet. Since the volume
of the sump is approximately 27,000 cubic feet, it is below capacity and can handle additional flow if
necessary.
4.0 ENVIRONMENTAL IMPACT ANALYSIS
4.1 Significance Thresholds
4.1.1 Surface Water Hydrology
The Los Angeles CEQA Thresholds Guide states that a project would normally have a significant impact on
surface water hydrology if it would:
HWQ-1 Cause flooding during the projected 50-year developed storm event, which would have
the potential to harm people or damage property or sensitive biological resources;
HWQ-2 Substantially reduce or increase the amount of surface water in a water body; or
HWQ-3 Result in a permanent, adverse change to the movement of surface water sufficient to
produce a substantial change in the current or direction of water flow.
4.1.2 Surface Water Quality
The Los Angeles CEQA Thresholds Guide states that a project would normally have a significant impact on
surface water quality if:
HWQ-4 Discharges associated with the Proposed Project would create “pollution,”
“contamination” or “nuisances” as defined in Section 13050 of the California Water Code.
Pollution means an alteration of the quality of the waters of the state to a degree,which unreasonably affects either of the following: (1) the waters for beneficial
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uses;32 or (2) facilities which serve these beneficial uses. Pollution may includeContamination.
Contamination means an impairment of the quality of the waters of the state bywaste33 to a degree which creates a hazard to the public health through poisoning orthrough the spread of disease. Contamination includes any equivalent effectresulting from the disposal of waste, whether or not waters of the state are affected.
Nuisance means anything which meets all of the following requirements: (1) isinjurious to health, or is indecent or offensive to the senses or an obstruction to thefree use of property, so as to interfere with the comfortable enjoyment of life orproperty; (2) affects at the same time an entire community of neighborhood, or anyconsiderable number of persons, although the extent of the annoyance or damageinflicted upon individuals may be unequal; and (3) occurs during, or as a result of thetreatment or disposal of wastes.
HWQ-5 The Proposed Project would cause regulatory standards to be violated, as defined in the
applicable National Pollutant Discharge Elimination System stormwater permit or Water
Quality Control Plan for the receiving water body.
Appendix G of the State CEQA Guidelines provides sample questions for use in an initial study to
determine a project’s potential for environmental impacts. According to the sample questions34 included
in Appendix G under Section VIII Hydrology and Water Quality and Section XVI Utilities and Service
Systems, a project would have a potentially significant impact if it would:
VIII.a) Violate any water quality standards or waste discharge requirements;
VIII.b) Substantially deplete groundwater supplies or interfere with groundwater recharge such thatthere would be a net deficit in aquifer volume or a lowering of the local groundwater tablelevel (e.g., the production rate of preexisting nearby wells would drop to a level which wouldnot support existing land uses or planned land uses for which permits have been granted);
32 Section 13050 of the California Water Code provides that the following definition for beneficial uses: “Beneficialuses’ of the waters of the state that may be protected against quality degradation include, but are not limited to,domestic, municipal, agricultural and industrial supply; power generation; recreation; aesthetic enjoyment;navigation; and preservation and enhancement of fish, wildlife, and other aquatic resources or preserves.”Beneficial uses have been designated by the Regional Water Quality Control Board for the Ballona Wetlands andthe Ballona Channel.
33 Section 13050 of the California Water Code provides the following definition for waste: “’Waste’ includes sewageand any and all other waste substances, liquid, solid, gaseous, or radioactive, associated with human habitation,or of human or animal origin, or from any producing, manufacturing, or processing operation, including wasteplaced within containers of whatever nature prior to, and for purposes of, disposal.
34 The remainder of the Appendix G Utilities and Service Systems sample questions (XVI.a, -b, and –d through -g)pertain to water supply, wastewater, and solid waste and are addressed in Sections IV.L.1, Water Supply,IV.L.2, Wastewater, and IV.L.3, Solid Waste, respectively.
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VIII.c) Substantially alter the existing drainage pattern of the site or area, including through thealteration of the course of a stream or river, in a manner which would result in substantialerosion or siltation on or off site;
VIII.d) Substantially alter the existing drainage pattern of the site or area, including through thealteration of the course of a stream or river, or substantially increase the rate or amount ofsurface runoff in a manner which would result in flooding on or off site;
VIII.e) Create or contribute runoff water which would exceed the capacity of existing or plannedstormwater drainage systems or provide substantial additional sources of polluted runoff;
VIII.f) Otherwise substantially degrade water quality;
VIII.g) Place housing within a 100-year flood plain as mapped on federal Flood Hazard Boundary orFlood Insurance Rate Map or other flood hazard delineation map;
VIII.h) Place within a 100-year flood plain structures which would impede or redirect flood flows;
VIII.i) Expose people or structures to a significant risk of loss, inquiry or death involving flooding,including flooding as a result of the failure of a levee or dam;
VIII.j) Be subject to inundation by seiche, tsunami, or mudflow; or
XVI.c) Require or result in the construction of new storm water drainage facilities or expansion ofexisting facilities, the construction of which could cause significant environmental effects.
The Initial Study prepared for the Proposed Project determined that the Proposed Project would have less
than significant impact with regard to sample questions VIII.b and VIII.g through -i of Appendix G of the
State CEQA Guidelines. The responses to these questions are discussed in Section VII, Effects Found Not
to be Significant. The Initial Study is provided in Appendix I.
The thresholds used in the Los Angeles CEQA Thresholds Guide to determine significant impacts to surface
water hydrology and surface water quality are inclusive of most of the thresholds provided in
Appendix G of the State CEQA Guidelines. Therefore, thresholds HWQ-1 through HWQ-5, above, are
used for the following analysis of the Proposed Project’s potential impacts, as well as the following
threshold that is based on Appendix G (listed above):
HWQ-6 Would the Proposed Project be subject to inundation by seiche, tsunami, or mudflow?
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4.2 Project Design Features
4.2.1 Surface Water Hydrology
Runoff from 16 acres at the southwest corner of Burns Campus currently flows from the 8-inch and
12-inch storm drains under the Sunken Garden and towards the riparian corridor to the north. Since these
storm drains are presently over capacity, the runoff from this area would be diverted to the McConnell
Avenue storm drain, which has capacity, by rerouting these storm drains to the southeast. The diverted
storm drains will be upsized so that they are no longer over capacity, and rerouting them will decrease
the volume of stormwater flowing into existing drainage facilities flowing under the Sunken Garden
toward the riparian corridor. In addition, the 24-inch LMU-owned storm drain leaving the Sunken
Garden and the 12-inch LMU-owned storm drain immediately to the east would be upsized to alleviate
flooding that occurs in the Sunken Garden during major storm events.
The diversion of flows into the City-owned storm drain that eventually empties in the McConnell Avenue
Storm Drain would require that an LMU-owned 24-inch storm drain at this location be upsized to a
36-inch storm drain to handle the additional runoff volume. The City-owned 36-inch storm drain already
has the necessary excess capacity and would not need to be increased in size.
4.2.2 Surface Water Quality
The north side of Leavey Campus is in compliance with Standard Urban Storm Water Mitigation Plan
requirements because stormwater runoff from Leavey Campus drains to the sump by the Drollinger
Parking Plaza. The remaining areas of the LMU campus were designed before this regulation was
adopted and were, therefore, designed in accordance with the standards in effect when they were built
out. All Proposed Project improvements on the LMU campus would be designed to current standards
and regulations.
4.3 Project Impacts
4.3.1 Surface Water Hydrology
HWQ-1 Would the Proposed Project cause flooding during the projected 50-year developed
storm event, which would have the potential to harm people or damage property or
sensitive biological resources?
The Sunken Garden acts as a retention area serving approximately 66 acres of Burns Campus. As
discussed above, the Sunken Garden experiences flooding during 10-year or greater storm events. The
24-inch LMU-owned storm drain leaving the Sunken Garden and the 12-inch LMU-owned storm drain
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immediately to the east, as well as the 8-inch and 12-inch storm drains at the southwest corner of Burns
Campus, would be upsized to alleviate flooding in this area. The design for the Proposed Project storm
drain system would divert stormwater flows from 16 acres within the southwestern portion of Burns
Campus, which currently flow into the riparian corridor, toward the south and into the McConnell
Avenue Storm Drain, as required by PDF-HWQ-1. The diversion of flows into the City-owned storm
drain that eventually empties in the McConnell Avenue Storm Drain would require that a LMU-owned
24-inch storm drain at this location be upsized to a 36-inch storm drain to handle the additional runoff
volume. The City-owned 36-inch storm drain already has the necessary excess capacity and would not
need to be increased in size. The McConnell Avenue Storm Drain currently has the capacity to
accommodate the additional flows from Burns Campus. Therefore, no adverse impacts on the existing
off-campus drainage system would occur.
Additionally, the Proposed Project would not cause flooding within the existing riparian corridor during
a projected 50-year developed storm event. Diversion of runoff from 16 acres at the southwest corner of
Burns Campus from the riparian corridor to the north to the McConnell Avenue Storm Drain to the south
would reduce the quantity of stormwater volume that is conveyed to the riparian corridor. The drainage
system would be designed to convey the total peak runoff rates and volumes generated by the Proposed
Project. Therefore, the Proposed Project would not cause flooding during a 50-year developed storm
event, which could harm people, damage property, or sensitive biological resources, and impacts would
be less than significant.
HWQ-2 Would the Proposed Project substantially reduce or increase the amount of surface water
in a water body?
HWQ-3 Would the Proposed Project result in a permanent, adverse change to the movement of
surface water sufficient to produce a substantial change in the current or direction of
water flow?
4.3.1.1 Construction
During construction, a Storm Water Pollution Prevention Plan would be implemented and best
management practices would be in place, in accordance with the California State Water Resources
Control Board, to provide temporary stormwater management for areas under construction to prevent
the volume of stormwater from adversely affecting water bodies and the stormwater conveyance and
treatment systems adjacent to the campus. These best management practices include proper scheduling of
construction activities and the preservation of existing vegetation which help to control the runoff
stormwater runoff quantity during construction. Construction of the Proposed Master Plan Project would
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City of Los Angeles IV.G-19 Loyola Marymount University Master Plan Project Draft EIRENV-2008-1342-EIR January 2010
not substantially reduce or increase the amount of surface water in the Ballona Channel and/or the
riparian corridor, and potential impacts to off-campus stormwater conveyance and treatment systems
related to stormwater runoff volumes would be less than significant with adherence to applicable
regulations. Nonetheless, mitigation measure MM-HWQ-1, which requires preparation of a Storm Water
Pollution Prevention Plan, and MM-HWQ-2, which requires preparation of a Standard Urban Storm
Water Mitigation Plan, are included to ensure compliance with regulations pertaining to surface water
hydrology.
4.3.1.2 Operation
As discussed above, storm drains that direct flows from the Sunken Garden would be rerouted and
upsized to alleviate flooding in the Sunken Garden. Also, as discussed above, diversion of runoff from
16 acres at the southwest corner of Burns Campus from the riparian corridor to the north to the
McConnell Avenue Storm Drain to the south would reduce the quantity of stormwater volume that is
conveyed to the riparian corridor. These improvements would decrease the stormwater flowing into
existing drainage facilities both on and off the campus; however, this decrease will not be substantial.
Because the reduction in flows to the riparian corridor would not be substantial, this decrease would not
have a significant impact on the Ballona Creek or the riparian corridor.
The Standard Urban Storm Water Mitigation Plan requires that stormwater facilities, such as infiltration
pits, stormwater cisterns and other stormwater retaining and detaining devices, be implemented to
reduce the rate and volume of stormwater runoff that would be conveyed to the stormwater conveyance
and treatment systems. For the Proposed Project Standard Urban Storm Water Mitigation Plan to adhere
to the standards set forth by the City of Los Angeles, the first 0.75 inch of rainfall from new impervious
areas must be treated and infiltrated whenever possible. When buildings and parking areas that currently
do not adhere to this regulation (due to their construction prior to the implementation of these
regulations) are replaced, the new buildings and parking areas would adhere to this regulation,
consequently reducing the volume of rainfall runoff produced on the campus and sent to the riparian
corridor and the McConnell Avenue Storm Drain. Thus improvements to the LMU campus would be
designed to current water hydrology standards and regulations. As several areas of the campus,
including Burns Campus, were designed before current regulations were in place, implementation of the
Proposed Project would bring the campus into compliance with current regulations.
Because the stormwater runoff rate and quantity is being reduced throughout the entire LMU campus,
the receiving water bodies will experience a decrease in stormwater volume. The exception is the
McConnell Avenue Storm Drain, which will experience an increase in the rate and quantity of
stormwater due to the diversion of runoff of 16 acres from the southwestern portion of Burns Campus to
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City of Los Angeles IV.G-20 Loyola Marymount University Master Plan Project Draft EIRENV-2008-1342-EIR January 2010
the McConnell Avenue Storm Drain to the south. The diversion of flows would require that a
LMU-owned 24-inch storm drain at this location be upsized to a 36-inch storm drain to handle the
additional runoff volume. In addition, the 12-inch LMU-owned storm drain immediately to the east of the
Sunken Garden, as well as the 8-inch and 12-inch storm drains at the southwest corner of Burns Campus
shall be upsized to alleviate flooding in the Sunken Garden area and to accommodate additional runoff
volume, as required by PDF-HWQ-2. The City-owned 36-inch storm drain already has the necessary
excess capacity and would not need to be increased in size. The direction of surface runoff flow for the
remainder of the campus would be similar to existing conditions.
For these reasons, the Proposed Project would not substantially reduce or increase the amount of surface
water in the Ballona Channel and/or the riparian corridor, and potential impacts to off-campus
stormwater conveyance and treatment systems related to stormwater runoff volumes would be less than
significant with adherence to applicable regulations. Nonetheless, mitigation measure MM-HWQ-1,
which requires preparation of a Storm Water Pollution Prevention Plan, and MM-HWQ-2, which
requires preparation of a Standard Urban Storm Water Mitigation Plan, are included to ensure
compliance with regulations pertaining to surface water hydrology.
4.3.2 Surface Water Quality
HWQ-4 Would the Proposed Project create “pollution,” “contamination” or “nuisances” as
defined in Section 13050 of the California Water Code?
Pollution means an alteration of the quality of the waters of the state to a degree,which unreasonably affects either of the following: (1) the waters for beneficial uses;or (2) facilities which serve these beneficial uses. Pollution may includeContamination.
Contamination means an impairment of the quality of the waters of the state bywaste to a degree which creates a hazard to the public health through poisoning orthrough the spread of disease. Contamination includes any equivalent effectresulting from the disposal of waste, whether or not waters of the state are affected.
Nuisance means anything which meets all of the following requirements: (1) isinjurious to health, or is indecent or offensive to the senses or an obstruction to thefree use of property, so as to interfere with the comfortable enjoyment of life orproperty; (2) affects at the same time an entire community of neighborhood, or anyconsiderable number of persons, although the extent of the annoyance or damageinflicted upon individuals may be unequal; and (3) occurs during, or as a result of thetreatment or disposal of wastes.
IV.G Surface Water Hydrology and Water Quality
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HWQ-5 Would the Proposed Project cause regulatory standards to be violated, as defined in the
applicable National Pollutant Discharge Elimination System stormwater permit or Water
Quality Control Plan for the receiving water body?
4.3.2.1 Construction
During construction of Proposed Project buildings and facilities, grading activities associated with
construction could result in a temporary increase in the amount of suspended solids and exposed soil
running off the campus. Spills and leaks associated with construction-related substances such as oils,
lubricants, paints, cleaning agents, and other fluids on the Proposed Project construction sites could
increase the potential for contamination. In the event of rainfall, construction site runoff originating from
the campus could result in sheet erosion of exposed soil. Erosion of exposed soil caused by runoff could
affect surface water quality in the vicinity of the campus, as well as downstream from the campus as
water flows towards the Pacific Ocean. Additionally, galvanized metal, painted surfaces, and preserved
wood are surfaces exposed to stormwater as a result of construction activities. These coatings and
treatments may contain metals, as well as other potential contaminants such as creosote. These potential
contaminants may enter receiving waters as surfaces corrode, flake, dissolve, decay, or leach through
contact with rainfall. Acidic constituents in rain may accelerate these processes. Soils also contain natural
levels of trace metals such as arsenic, copper, and zinc.
Herbicides, insecticides, and rodenticides are used commonly at construction sites. The unnecessary or
improper application of these pesticides may result in receiving water contamination and pollution
through drift, or transport of soil particles by wind and rain fall. Also, pesticides may inadvertently be
released to the environment if not properly labeled, handled, or stored. As with pesticides, the storage,
handling, and use of other chemicals, such as fuels, paints, solvents, and petroleum products, associated
with construction activities could cause water quality impacts if spilled or released near surface waters.
Miscellaneous wastes include wash from concrete mixers, solid waste resulting from vegetation removed
during land clearance, wood and paper materials from building products packaging, food containers, and
sanitary wastes. The discharge of these wastes can lead to unsightly and polluted waterways. Concrete
wash water can be toxic and requires proper control. Therefore, construction-related erosion and
construction site contamination could result in a potentially significant impact to surface water quality.
LMU would adhere to the requirements of the National Pollutant Discharge Elimination System, which
includes preparation of a Storm Water Pollution Prevention Plan prior to the issuance of grading permits,
and the Storm Water and Urban Runoff Pollution Control provisions from the Los Angeles Municipal
Code, which includes the preparation of a Standard Urban Storm Water Mitigation Plan. The Standard
Urban Storm Water Mitigation Plan would incorporate Best Management Practices by requiring controls
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of pollutant discharges that utilize best available technology economically achievable and best
conventional pollutant control technology to reduce pollutants. Potential impacts associated with
construction of the Proposed Project would be less than significant with adherence to applicable
regulations. Nonetheless, mitigation measure MM-HWQ-1, which requires preparation of a Storm Water
Pollution Prevention Plan, and MM-HWQ-2, which requires preparation of a Standard Urban Storm
Water Mitigation Plan, as well as MM-HWQ-3 through MM-HWQ-7 are included to ensure compliance
with regulations pertaining to surface water quality.
4.3.2.2 Operation
Surface water quality is generally affected by the length of time since the last rainfall, rainfall intensity,
urban uses of the area, and quantity of transported sediment. Typical urban water quality pollutants
usually result from motor vehicle operations, oil/grease residues, fertilizer/pesticide uses, human/animal
littering, careless material storage/handling, and poor property management. The majority of pollutant
loads are usually washed away during the first flush of a storm occurring after the dry-season period.
Street and parking lot/garage-generated pollutants typically contain atmospheric pollution, tire-wear
residues, petroleum products, oil, and grease, fertilizer and pesticide wash-offs, chemical spills, as well as
animal droppings and litter types of wastes. The pollutants are washed from street surfaces by a rainfall
adequate to produce runoff. The amount of pollutants washed off the street surface is a function of the
amount of pollutants that have accumulated on street surfaces and the frequency and amount of surface
water flow flushing the pollutants from storm and non-storm events (such as hosing down of walkways
and parking garage surfaces). These pollutants have the potential to degrade water quality and may
result in significant impacts.
The current building standards for parking structures require the installation of oil and grease traps and
other mechanisms to treat water before being sent to the storm drain system. The Proposed Project will
replace significant areas of surface lot parking (which do not have these mechanisms in place to treat
runoff) with structure parking above or below grade. Herbicides, insecticides and rodenticides are used
commonly. The unnecessary or improper application of these pesticides may result in receiving water
contamination and pollution through drift, or transport of soil particles by wind and rain fall. Also,
pesticides may inadvertently be released to the environment if not properly labeled, handled, or stored.
LMU maintains on-campus storage in accordance with requirements of the California Department of
Pesticide Regulation.
All improvements to the LMU campus would be designed to current water quality standards and
regulations. Several areas of the campus were designed before current regulations. Therefore, when
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existing buildings and parking areas are replaced, the new buildings and parking areas would adhere to
current regulations, consequently reducing the volume of rainfall runoff produced on the campus and
sent to the riparian corridor and the McConnell Avenue Storm Drain. As such, the Proposed Project
would improve these areas to comply with current regulations and therefore, would improve water
quality in these areas and reduce the volume of rainfall runoff produced on the campus and sent to the
riparian corridor and the McConnell Avenue Storm Drain.
Potential impacts associated with operation of the Proposed Project would be less than significant with
adherence to applicable regulations. Nonetheless, mitigation measure MM-HWQ-1, which requires
preparation of a Storm Water Pollution Prevention Plan, and MM-HWQ-2, which requires preparation of
a Standard Urban Storm Water Mitigation Plan, as well as MM-HWQ-3 through MM-HWQ-7 are
included to ensure compliance with regulations pertaining to surface water quality.
HWQ-6 Would the Proposed Project be subject to inundation by seiche, tsunami, or mudflow?
The elevation of the campus ranges from approximately 66 to approximately 150 feet above mean sea
level. According to the City of Los Angeles Safety Element, the LMU campus is not located within a
tsunami run-up zone, which is the area that might be inundated during a tsunami. Therefore, tsunamis
are not considered a significant hazard on the LMU campus.35
According to the City of Los Angeles Safety Element, the campus is not located in a potential inundation
area that could adversely affect the campus in the event of earthquake-induced dam failures or
seiches (wave oscillations in an enclosed or semi-enclosed body of water). Therefore, the potential
for inundation at the campus as a result of an earthquake-induced seiche or dam failure is considered
low.36
Finally, the campus is not located in a City-designated Landslide or Hillside Area, however the
Westchester Bluffs below the campus are located in a state-designated Earthquake-Induced Landslide
Hazard Zone because of their steep angle. Due to the sandy, uncemented nature of bluff materials, the
bluff face is generally considered susceptible to erosion and sloughing. As stated in Section IV.E,
Geology, Proposed Project impacts related to slope stability would be less than significant with
preparation of Project-level (i.e., building-specific) geotechnical evaluations, including slope stability
analyses to verify the factor of safety of the bluff slope, and adherence to applicable building codes
35 MACTEC Engineering and Consulting, Inc, Geotechnical Evaluation: Proposed Master Plan Project, LoyolaMarymount University.
36 MACTEC Engineering and Consulting, Inc, Geotechnical Evaluation: Proposed Master Plan Project, LoyolaMarymount University.
IV.G Surface Water Hydrology and Water Quality
City of Los Angeles IV.G-24 Loyola Marymount University Master Plan Project Draft EIRENV-2008-1342-EIR January 2010
governing slope stability. Moreover, no buildings or structures would be constructed within the northern
portion of campus on the bluffs, as this area is designated by the proposed LMU Specific Plan as a
Buffer/Open Space Planning Area. Given the above, impacts related to inundation by seiche, tsunami, or
mudflow are considered to be less than significant.
4.4 Project Design Features and Mitigation Measures
PDF-HWQ-1 The runoff from 16 acres at the southwest corner of Burns Campus shall be diverted to
the McConnell Avenue storm drain by rerouting these storm drains to the southeast.
PDF-HWQ-2 During Proposed Project construction of components on Burns Campus, the 24-inch
LMU-owned storm drain leaving the Sunken Garden and the 12-inch LMU-owned storm
drain immediately to the east of the Sunken Garden, and the 8-inch and 12-inch storm
drains at the southwest corner of Burns Campus, shall be upsized to alleviate flooding in
the Sunken Garden area and to accommodate additional runoff volume.
The following mitigation measures would address impacts to surface water hydrology and water quality
and ensure that impacts remain less than significant.
MM-HWQ-1 Prior to the start of soil-disturbing activities for individual projects on campus, a Notice
of Intent (NOI) and Storm Water Pollution Prevention Plan shall be prepared in
accordance with, and in order to partially fulfill, the California SWRCB Order No. 99-08-
DWQ, National Pollutant Discharge Elimination System General Permit No. CAS000002
(General Construction Permit). The Storm Water Pollution Prevention Plan shall meet the
applicable provisions of Sections 301 and 402 of the Clean Water Act and Chapter 6
Article 4.4, Storm Water and Urban Runoff Pollution Control from the City of Los
Angeles Municipal Code by requiring controls of pollutant discharges that utilize best
available technology economically achievable and best conventional pollutant control
technology to reduce the rate and quantity of stormwater runoff. Examples of best
available technology economically achievable and best conventional pollutant control
technology that may be implemented during site grading and construction could include
straw hay bales, straw bale inlet filters, filter barrier infiltration pits, stormwater cisterns,
and silt fences.
MM-HWQ-2 LMU shall prepare and implement for individual projects on campus a Standard Urban
Storm Water Mitigation Plan in accordance with the requirements of Chapter 6 Article
4.4, Storm Water and Urban Runoff Pollution Control, from the City of Los Angeles
Municipal Code, to ensure that stormwater runoff water quality is managed through
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implementation of appropriate and applicable Best Management Practices. Prior to
issuance of any grading or building permits for individual projects on campus, the City
of Los Angeles Department of Public Works must approve the Standard Urban Storm
Water Mitigation Plan.
MM-HWQ-3 During the construction of individual Proposed Project components, Proposed Project
contractors shall properly store hazardous materials to prevent contact with precipitation
or runoff.
MM-HWQ-4 During Proposed Project construction and subsequent operation, Proposed Project
contractors and LMU, respectively, shall develop and maintain effective monitoring and
cleanup programs for spills and leaks of hazardous materials.
MM-HWQ-5 During Proposed Project construction and subsequent operation, Proposed Project
contractors and LMU, respectively, shall place equipment to be repaired or maintained in
covered areas on a pad of absorbent material to contain leaks, spills, or small discharge.
MM-HWQ-6 During Proposed Project construction and subsequent operation, Proposed Project
contractors and LMU, respectively, shall provide periodic and consistent removal of
landscape and construction debris.
MM-HWQ-7 During Proposed Project construction and subsequent operation, Proposed Project
contractors and LMU, respectively, shall sweep parking lots at regular, frequent intervals
to remove debris and shall also remove any significant chemical residue on the Project
site through appropriate methods.
4.5 Level of Impact After Mitigation
All Proposed Project-specific construction and operational impacts would be less than significant;
therefore, no unavoidable significant surface water hydrology and water quality impacts would result
from implementation of the Proposed Project. Nonetheless, mitigation measures MM-HWQ-1 through
MM-HWQ-7 are recommended to ensure compliance with regulations pertaining to surface water
quality.
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4.6 Cumulative Impacts
As discussed in Section III, General Description of Environmental Setting, several related projects are
proposed and/or planned within the campus vicinity. All of the projects are proposed upstream of the
Ballona Wetlands and Ballona Channel; none of the related projects are proposed upstream of the
McConnell Avenue Storm Drain. The majority of these projects will need to implement a Stormwater
Pollution Prevention Plan and a Standard Urban Stormwater Mitigation Plan. Compliance with these
plans would result in a cumulative decrease in stormwater runoff rate and volume and, consequently, a
decrease in the amount of pollutants carried by stormwater runoff. Considered together with related
projects, the Proposed Project’s contribution to cumulatively significant surface water hydrology and
water quality impacts would be less than significant.37
37 KPFF Consulting Engineers, LMU Surface Water Hydrology and Water Quality Analysis, 8.