iv g hydrology and water quality - la city planning...iv.g surface water hydrology and water quality...

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.

IV.G Surface Water Hydrology and Water Quality


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.



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.



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.



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.



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).



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.



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,



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).



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



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.



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.



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



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.



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?



4.2 Project Design Features


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.


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


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



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



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



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.


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.



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



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



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.



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



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.


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.


contractors and LMU, respectively, shall provide periodic and consistent removal of

landscape and construction debris.


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.



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.

iv g hydrology and water quality - la city planning...iv.g surface water hydrology and water quality...

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