Los Angeles Department of Water and Power Case Study

8/12/2019 Los Angeles Department of Water and Power Case Study

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Following case study was extracted from published WaterRF report titled Effects of Climate

Change on Water Utility Planning Criteria and Design Standards (Order# 4154)

LOS ANGELES DEPARTMENT OF WATER AND POWER

Utility Overview

Description of Util ity

The Los Angeles Department of Water and Power (LADWP) is a retail water andelectricity provider located in Los Angeles, California. LADWP services approximately 713,000

water connections with a typical delivery of approximately 660,500 acre-feet per year (as of CY

2007) with an average per capita use of 141 gallons per person per day. The majority ofLADWP‟s customers are residential (66%) with single-family (38%) and multi-family (29%),

followed by commercial/industrial (20%), non-revenue water (7%), and municipal (6%). Figure

1 details the LADWP service area.

Figure 1 LADWP water service area



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LADWP drinking water supplies come from imports (88%), local groundwater (11%),

and recycled water (1%). LADWP owns and operates the Los Angeles Aqueduct (LAA), which

provides approximately 35% of the department‟s imported supplies. The LAA extends

approximately 340 miles from the Mono Basin to Los Angeles. There are eight reservoirs(including the terminal Los Angeles reservoir) with a combined storage capacity of 300,560

acre-feet and 12 hydroelectric power generation facilities along the LAA that can generate up to

250 megawatts (Figure 2).

Figure 2 LADWP’s Los Angeles aqueduct system

LAA water originates from snowmelt runoff from the Eastern Sierras in the late spring

and summer, after most of the year‟s precipitation has already occurred and is conveyed the

entire distance by gravity alone. From 1970 through 1993, LAA deliveries suppliedapproximately 65 percent of the City‟s total water supply. In 1994, LADWP began its

environmental enhancement and mitigation efforts in the Mono Basin and Owens Valley,

resulting in a reduction of LAA deliveries to the City. Currently, the LAA deliversapproximately 35 percent of the City‟s water supply. LADWP anticipates that LAA supplies



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will be at this level for the foreseeable future as environmental commitments and the potentialimpacts from climate change to cumulatively reduce deliveries from the LAA.

LADWP, on average, purchases approximately 53% of its water from Metropolitan

Water District of Southern California (MWD), which delivers water via the California State

Water Project (SWP) and the Colorado River Aqueduct (CRA), to supplement its own importedand local supplies. MWD‟s service area includes the Southern California coastal plain. The

quantity of water bought from MWD varies yearly and depends on LAA deliveries and the

availability of other sources. LADWP does however have a “take or pay” contract withMetropolitan through a “purchase order” for a fixed amount of water priced at Metropolitan‟s

less expensive Tier 1 rate. The amount of water that LADWP can purchase in any one year

under the purchase order was determined by each member agency‟s “base year” amount asdefined by LADWP‟s highest fiscal year purchase of firm supplies from Metropolitan between

fiscal year 1989/90 and 2001/02. Under the purchase order, agencies can vary its purchase

amounts from year to year; however, if the member agency does not meet its minimumcommitment during the ten years, it is still obligated to pay for the full purchase order. Under the

terms of its current purchase order, LADWP can purchase a maximum of 304,970 acre-feet in

any one year and has committed to purchasing 2,033,132 acre-feet of supplies by December 31,

2014. LADWP major sources of water are shown on Figure 3.



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Figure 3 Major sources of water for LADWP

Other sources of water supply include local groundwater. The City of Los Angeles owns

water rights in three Upper Los Angeles River Area groundwater basins: San Fernando, Sylmar,and Eagle Rock as well as Central and West Coast Basins. However, localized water quality

issues have impacted the exercise of LADWP‟s water rights in the West Coast Basin and the San

Fernando Basin. LADWP is currently undertaking a Groundwater System Improvement Studyfor the San Fernando Basin which provides over 80 percent of the City‟s groundwater supplies.

Recycled water is also a water supply source for LADWP. The City‟s Department of

Public Works, Bureau of Sanitation is responsible for the planning and operation of the

wastewater program, which is the source of recycled water. As of 2005, almost 65,000 AFY ofthe City‟s wastewater is recycled. Approximately 4,500 AFY of recycled water is used for

municipal and industrial (M&I) purposes to reduce demands for imported water. The City ofLos Angeles Water Supply Action Plan indicates that the City plans to increase its M&I recycled

water use to at least 50,000 AFY by 2019.LAA water is treated by the Los Angeles Aqueduct Filtration Plant. The plant was built

in 1986 and can treat 600 million gallon daily. It uses ozonation and rapid rate deep bed

filtration as treatment processes. In addition, fluoridation was added to the plant. LADWP isevaluating enhanced coagulation as a pilot to remove arsenic. LADWP is converting to



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chloramine treatments for disinfection prior to distribution. LADWP is replacing chlorine bychloramines as a disinfectant because chloramines form less disinfection by-products. LADWP

monitors its local groundwater supply from the production wells for all contaminants before it

enters the distribution system. If water quality problems are detected, groundwater supply is

isolated and retested. Treated water available for distribution is stored in LADWP‟s 100 in-cityreservoirs and storage tanks.

Organizational Structure

LADWP is a revenue-generating department of the City of Los Angeles. LADWP‟s

budget and policies are approved by a five-member Board of Water and Power Commissioners.The Board members are appointed by the Mayor and confirmed by the City Council for five-year

terms. LADWP's water operations are financed solely by the sale of water services. Capital

funds are raised through the sale of bonds.

Review of Current Planning Documents and Design Standards

The following paragraphs summarize Los Angeles Department of Water & Power‟s

(LADWP) current planning criteria and design standards for sizing of facilities (includingconveyance, treatment, pumping, pipelines, and storage), based on the review of select utility

documents.

Water Supply Reli abili ty and Water Demand Projections

LADWP‟s water planning processes (water supply reliability and water demand projections) are detailed in the department‟s 2005 Urban Water Management Plan (UWMP). In

the midst of climate change, local groundwater contamination, diminishing snowpack in the

Eastern Sierra, potential regional water allocations, and drought, the Los Angeles Mayor and

LADWP published the City of Los Angeles Water Supply Action Plan (WSAP) titled Securing

L.A.‟s Water Supply in May 2008. It clearly refines the City of L.A.‟s long-term water supply policy that is to sustain a reliable supply of water while meeting current and future demand. With

the WSAP, LADWP seeks to maintain water supply reliability through conservation and localresource development. More details on the 2005 UWMP and 2008 WSAP are included in the

Climate Change Approach section below.

Sizing of Facilities (conveyance, treatment, pumping, pipelines, and treated water storage)

LADWP prepared design guidelines for their gravity and pumping systems in 1997,

which are used for sizing new distribution facilities and determining the capacity of existingfacilities to meet projected demands. These criteria are intended to provide operational

flexibility to respond to both planned and emergency system outages. LADWP notes that thesecriteria may be modified, however this decision should be based on professional judgment and

cost-benefit analyses.



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Conveyance

LADWP has developed fire flow requirements to meet a minimum 20-psi residual

pressure during ultimate peak hour (Table 1).

Table 1

Fire flow requirements

Zoning/ Land

Development Type

Max Hydrant

Spacing (feet)

Continuous Mains –

Minimum Fire Flow

Dead End Mains –

Minimum Fire Flow

Low DensityResidential

600 2000 gpm from 3 adjacenthydrants flowingsimultaneous (1000 gpmfrom most critical hydrant)

1500 gpm from last 2hydrants (500 gpmfrom last hydrant)

High Density

Residential & LimitedCommercial

300 – 600 4000 gpm from 4 adjacent

hydrants flowingsimultaneous (1000 gpm

from most critical hydrant)

2000 gpm from last 2

hydrants (750 gpmfrom last hydrant)

Commercial & LightIndustrial 300 6000 – 9000 gpm from 4-6adjacent hydrants flowing

simultaneous (1500 gpmfrom most critical hydrant)

3000 gpm from last 2hydrants (1000 gpm

from last hydrant)

CommercialManufacturing &Heavy Industrial

300 12,000 gpm available to any block

12,000 gpm availableto any block

LADWP has also established emergency requirements for the design of their watersystem facilities (Table 2).

Table 2Emergency requirements for water system facility design

ConditionMin Pressure

(psi)Time

Normal (Res/ Comm/Ind) 43 Ultimate Peak-Hour (UPH)

Fire Gravity 20 UPH

Pump20

Ultimate Max Demand (UMD) – 6 criticalhours

Emergency (first24 hours)

GravityPositive pressure

Service Zone: UPHLarge System: Ultimate Typical SummerDay (UTSD)

Pump20

UTSD – 6 critical hours with fire flow,4 hours if more than 1 power source

For the sizing of trunk lines and supply mains, LADWP allows a maximum headloss

during peak hour of 3 ft per 1000 ft length. The rule of thumb for these lines is that the diameter



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= 6 x (Maximum Day Demand in cfs)^1/2

. Distribution mains are sized for 5-7 ft of headloss per1000 ft length during ultimate peak hour.

Pumping

Pumping capacity should be sufficient to supply ultimate max-day demand plus

requirements for other systems supplied. Typical pump stations have 2-4 operating units, a

standby unit, and emergency unit. Total operating capacity must supply at least 115% of thesystem‟s residential ultimate max-day demand plus the 24-hour average of all other system

demands including fire flow. An initial pump station sizing estimate of 200 square-feet per

pump unit is used to approximate space for pumps 50 HP or less, with no more than 3 units.

Storage

LADWP has developed preliminary guidelines to be used for storage sizing purposes,

however actual storage volumes are based on detailed analysis of the area being served

(hydrographs, emergency outage scenarios, backup supplies) (Table 3).

Table 3Storage volumes

Emergency storage in daily regulatory reservoirs is equal to:

2-7 days of ultimate maximum week demand

3-12 days of ultimate mean-annual demand – OR-

6-20 days of ultimate winter time demand

Total storage for LADWP‟s facilities is equal to emergency storage plus regulatory

storage. Regulatory storage is 100,000 gallons per cfs of ultimate maximum daily demand.Emergency storage is 540,000 gallons or 100,000 gallons per cfs of ultimate maximum day

demand, whichever is greater. From a practical standpoint, the smallest tank proposed is

typically 1 million gallons, although smaller tanks may be acceptable for specific site restrictionsand demand requirements. Tank elevation is designed to be a minimum of 100 feet (125 preferred) above the highest elevation served.

Final design of facilities is confirmed using hydraulic modeling. LADWP defines the

critical design period as typical summer day demand (65-70% maximum day demand), critical 6-

hour 35% daily consumption, critical 4-hour 30% daily consumption.

Period (Ultimate) Regulatory Storage per cfs Demand

Maximum Day 0.22 MG

Maximum Week 0.44 MG

Maximum Month 1.32 MG

Maximum 4 Months 4.0 MG

Annual 20 MG



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Treatment

LADWP‟s design guidelines also address the water quality implications of a proposed

design. Concerns such as disinfection by-product potential, disinfection contact time, and future

drinking water regulations are factored into their facility design decisions. LADWP currentlymeets all the disinfection by-product standards and is in the process of switching from chlorine

to chloramines to maintain water disinfectant residual, which will further reduce levels of total

trihalomethanes. LADWP is also in compliance with the Surface Water Treatment Rule forthrough the design and construction of facilities to provide only filtered water from their

reservoirs.

AWWA Standards

LADWP uses applicable AWWA standards as appropriate to support design decisions.

Climate Change Approach

Policy

The basic policy principles that guide LADWP‟s water planning process are detailed in

the department‟s 2005 Urban Water Management Plan (UWMP). The UWMP is updated every

five years pursuant to the Urban Water Management Planning Act (Act). The Act requires urbanwater suppliers to prepare plans that describe and evaluate reasonable and practical efficient

water uses, recycling, and conservation activities. LADWP‟s 2005 UWMP defines policies for

water resources and water planning, such as water demand, water conservation, integratedresources planning, water supply reliability, and alternative water supply.

In the midst of climate change, local groundwater contamination, diminishing snowpack

in the Eastern Sierra, potential regional water allocations, and drought, the Los Angeles Mayor

and LADWP published the City of Los Angeles Water Supply Action Plan (WSAP) titled

Securing L.A.‟s Water Supply in May 2008. The WSAP is a blueprint for creating sustainablesources of water for the future of Los Angeles. It clearly refines the City of L.A.‟s long-term

water supply policy that is to sustain a reliable supply of water while meeting current and futuredemand. Under the WSAP, the City will not rely on new imported water sources, but instead will

engage in developing alternative water supplies through the implementation of both short-term

and long-term strategies. With the WSAP, LADWP seeks to maintain water supply reliabilitythrough conservation and local resource development.

The LADWP has been a Charter Member of the California Climate Action Registry since

September 2002. Los Angeles is also a signatory to the U.S. Mayors Climate Protection

Agreement along with more than 900 US mayors. The GHG emissions reduction strategy is primarily focused on the power system of LADWP, since electricity generation is a significant

source of direct GHG emissions. Since 1998, with the divestiture of Colstrip and Deseret coalcontracts and shutdown of Mohave Generating Station at the end of 2005, the LADWP has taken

steps to move away from dependence on coal resources, including discontinuation of itsinvolvement in the development of Unit 3 at Intermountain Generating Station. The LADWP is

undergoing a utility-wide transformation in how it supplies, transmits, delivers and uses

electricity. In 2007, the City of Los Angeles unveiled its “Green LA Plan,” an aggressive plan



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for reducing the City‟s overall greenhouse gas (GHG) emission levels to 35% below 1990 levels by 2030, of which the LADWP plays a lead role through its renewables, energy

efficiency/demand side management programs, tiered customer rates, green building/LEED

incentives that complement the City‟s Green Building Ordinance, and water management

programs. The utility is taking immediate action now, not in 2012, to reduce its emissions.Accordingly, LADWP has established an aggressive goal of developing and owning new

renewable generation to meet its 20% by 2010 mandate and 35% by 2020 Renewables Portfolio

Standard (RPS) mandate. Since 2005, LADWP has increased its renewable energy mix from 3%to 10% in fall 2008. LADWP has identified the need for new staff to work on climate change.

LADWP is in the process of hiring an employee that will be dedicated to working on GHG

mitigation and adaptation for their water section.The California Global Warming Solutions Act of 2006, also commonly known and

referred to as Assembly Bill 32, requires the California Air Resources Board (ARB) to adopt a

Scoping Plan by January 1, 2009 to provide a framework for implementing the aggressiveemission reduction goal of achieving 1990 statewide emission levels by 2020. The ARB adopted

the Scoping Plan on December 11, 2008. This plan includes emission reduction measures for the

water sector, including water use efficiency, water recycling, water system energy efficiency,

reuse of urban runoff, and increase renewable energy production. Additionally, the Scoping Plan

proposes a public goods charge for water. The LADWP will monitor the regulatorydevelopments over the next 24 months, including establishment of the public goods charge and

use of collected revenues to ensure that revenues collected support LADWP‟s GHG strategies

related to the water system and used directly within our service territory.LADWP, in collaboration with the Department of Public Works, the Bureau of

Sanitation, public stakeholders, and other agencies, has developed an Integrated Resources Plan

(IRP). This IRP uses an approach of technical integration and community involvement to guidewater resources policy decisions and facilities planning. The IRP discusses alternatives that the

City could implement that would provide water supply benefits, along with other benefits such as

protection of the environmental by reducing pollutants going into ocean and rivers, creation of

more open space, flood control, and improving the overall quality of life for the citizens of Los

Angeles. LADWP is currently working with other City‟s department on more aggressive actionstowards efficient landscaping. The City of Los Angeles is also in the process of discussing the

development of new policies with other City‟s departments, the Bureau of Sanitation, and othercities on state-of-the-art water conservation.

The LADWP Board of Commissioners sets the billing rates subject to approval of the Los

Angeles City Council by ordinance. Through their tiered rate structure, LADWP has securedfunding mechanisms for water conservation and recycling and has incorporated climate zonings.

Additionally, LADWP charges new developments through a connection fee when broadening

their recycling water system.

One of LADWP‟s main vulnerabilities is the observed and predicted decrease in run-offfrom the Eastern Sierras. However, creating and adopting policies to address this concern will

require greater understanding regarding particular uncertainties associated with climate change predictions. Ultimately, LADWP is interested in addressing these vulnerabilities to better

understand the magnitude and gravity of source impacts and develop and invest in the most judicious and needed policies.



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Planning

Planning at LADWP is concerned with a long-term commitment to water use efficiency

and the environment while providing a safe, reliable, and affordable water supply to their

customers. It focuses on forecasting future water demand, and evaluating current supply capacityand the need for future new supply sources and water rights. This section covers LADWP‟s

vulnerability assessment as it relates to planning, planning criteria assessment (with a focus on

impacts and uncertainties) and adaptive strategies to incorporate climate change into planning.Climate change studies indicate that a wide range of impacts could potentially affect the

water utility‟s planning function, and more precisely, water demand and water supply. LADWP

anticipates reduced run-off, changes in snowmelt timing, reduced recharge, greater flood peaks,increased demand, temperature extremes, poor water quality, sea level rise, and ecological

impacts having the greatest impact on their long range water supply planning criteria due to

climate change.Water Demand Forecasting. Water demand forecasting at LADWP is conducted in-

house. LADWP expects that actual demand (indoors and outdoors [mainly irrigation]) would

increase with increasing atmospheric temperature. LADWP forecasts water demand based on

historical trends in billing data, projections of water conservation, and projections of

demographics provided by the Southern California Association of Governments (SCAG). Thedemographic projections used in LADWP‟s demand planning for the 2005 UWMP were

obtained from the SCAG 2004 Regional Transportation Plan and were modified using MWD‟s

land planning tool to represent LADWP‟s service area. The current demand forecasting approachuses demographic projections and integrates variable parameters, such as temperatures and

precipitations. As climate change needs to be considered further, LADWP anticipates changes to

its demand planning modeling such as including economic projections and changing currentmodel assumptions. Projected water demands through 2030 from LADWP‟s 2005 UWMP are

shown in Figure 4.

Figure 4 Projected water demands through 2030



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Water Supply Planning. LADWP‟s major water supply sources include imported waterfrom the LAA, local groundwater, and supplemental water purchased from MWD. Recycled

water for irrigation and industrial purposes constitutes a minor water supply source but is

progressing. LADWP currently uses the 5-year update cycle for short-term planning efforts that

is required under the UWMP, which is mandatory in California. LADWP has not done a recentassessment of its existing water supply planning criteria that may be susceptible to the impacts of

climate change. LADWP plans to evaluate its water resources planning efforts on a continual

basis to take into account changing conditions and the dynamic water supply situation thatimpacts the City‟s water supplies.

LADWP uses various hydrologic data (snowpack, rainfall, storage, etc.) to forecast their

imported water supplies. Forecasts are typically done with exceedance levels to reflectuncertainty of future precipitation events. LADWP‟s historical record of hydrology used for

planning purposes is approximately 75 years. One of LADWP„s goals for their long-term water

supply planning is to create near-term reliability which will also serve as a measure for climateadaptation. LADWP‟s UWMP assesses service area reliability under three hydrologic

conditions: average (or normal weather), single dry year (such as a repeat of the 1976-77

drought), and multi-year drought (such as a repeat of the 1987-92 drought). Under these

scenarios for the 25 year projection period, LADWP‟s supply is expected to be reliable, with

adequate supplies available to meet projected demands. Under dry weather conditions, waterdemands are expected to be approximately 5 percent greater than in normal years. In a 2030 dry

year scenario, the percentage of supply from the LA Aqueduct is expected to decrease from 31%

of the total supply to 10% of the total supply. MWD imported supplies are expected to coverthis difference. In case of severe drought, LADWP will purchase more water from MWD and

will pass the charge on to customers.

LADWP uses the State‟s water supply planning standards, outlined in Urban WaterManagement Planning guidelines, with a typical planning horizon of 25 years for water

resources, which is five years longer than required, but commonly used for water and land use

planning purposes. The LADWP typically uses a 100-year life-cycle planning horizon for major

pipelines and storage facilities. System operations require a one-year planning horizon. Every

year, LADWP holds an in-house water supply symposium during which the operating criteria aredetermined. Annual LAA operations are largely driven by its delivery capacity dependent upon

yearly snowpack from the Eastern Sierras, by the limited quantity of groundwater available to pump (due to the contamination on the San Fernando Valley), and by conjunctive use

opportunities. Based on these estimated operation criteria, LADWP is able to estimate additional

water purchases from MWD to sustain reliability. The LAA delivery is vulnerable to climatechange as it highly depends on the snowpack quantity in the Eastern Sierras. LADWP is faced

with the challenge to accurately predict the effects of climate change to their operations. To

better understand the potential impacts of climate change, LADWP will undertake an evaluation

study on potential impacts to the LAA, as well as locally.The limited LAA storage capacity does not allow the system to store large water volume

from greater flow peaks from potential early run-off or intense storm events. Predicted earlierrun off from climate change may result in limited supply availability through the summer

months, while water spillage/loss may occur during intense storm events. LADWP sees waterloss of most concern because it constitutes a loss of economical value. Spillage can also be of

concern to the ecosystems and habitat surrounding the LAA (e.g., Owen‟s Lake).



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LADWP is also concerned there is a potential impact to Bay-Delta fisheries due toclimate change, which may limit the availability of supply to MWD. Changes in the natural

watershed, waterways, and biota (ex. Algal balance, spikes in turbidity in raw water, and the

presence of non-native invasive species, such as Quagga Mussels) are current water quality

impacts LADWP believes may be associated with climate change. LADWP is also bound toenvironmental enhancement and restoration projects along the LAA, which result in reductions

in LAA deliveries. Deterioration of water supply quality and environmental restoration projects

may further impact LADWP‟s water supply availability.Planning Criteria Adaptation Strategies. The 2005 UWMP indicates that climate

change may impact LADWP‟s surface water supplies f rom the Los Angeles Aqueduct and

MWD. The UWMP states that although science has not yet determined definitive impacts onthese supplies, most scientists believe that climate change would impact timing of precipitation

for the West. LADWP will continue to monitor climate change research, especially related to the

Eastern Sierras, and will study potential actions to adapt to future changing conditions.LADWP‟s biggest opportunities to incorporate climate change into their planning

practice reside in outlining the LAA operational impacts and understanding the climate change

impacts to the Eastern Sierra snowpack to meet near-term reliability. While a policy would be

most certainly needed to implement these changes, LADWP is developing adaptive strategies.

In response to substantial variability and reliability concerns of surface water suppliesfrom LAA and MWD as a result of climate change, LADWP plans to expand its existing supply

source and diversify its sources without increasing reliance on imported sources. To increase the

reliability of their system, LADWP is considering alternative supplies, such as water transfers,increased water recycling, storm water capture and beneficial reuse of urban runoff (dry weather

and wet weather options), enhanced local groundwater basin production (routine groundwater

monitoring, conjunctive use, groundwater recharge through the use of spreading grounds,groundwater storage, San Fernando Groundwater Basin clean-up acceleration). Desalination is

also a potential new supply, but it is not currently the focus of LADWP‟s planning efforts. Some

of these alternative supplies are included in the IRP, where LADWP examines ways to decrease

potable water needs by expanding the City‟s recycled water program and encouraging rainwater

harvesting, increasing water efficiency by installing smart irrigation devices that reduceirrigation demands, and increasing groundwater resources by using wet weather runoff to

recharge the aquifer. Additional management programs are being developed such as conservationand pricing.

LADWP has achieved significant success in water conservation. In the 2005 UWMP, the

City increased its conservation goal to a 20 percent reduction to lessen its reliance on importedwater and provide a drought-proof resource. Moreover, LADWP is currently participating in

cooperative efforts to increase supplies through the Greater Los Angeles Integrated Regional

Water Management Planning process. Another adaptation measure for LADWP‟s long-term

water supply planning consists of integrating climate change in their demand and supplyforecast.

To address greater flow peaks and potential consequent spillage, LADWP is exploring a program for enhanced maintenance of the LAA (i.e., debris clearing), expansion of the LAA

areas that are congested or spillage-prone, and development of watershed management programs.Further adaptation strategies related to ecosystems will be discussed in the Watershed and

Environmental Regulatory section.



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While the implementation of the aforementioned strategies are not driven solely byclimate change, LADWP plans to perform a study to evaluate and develop proposed adaptation

measures to address climate change impacts to the LAA. The request for proposal was issued

mid-2008. The scope of work is to review and evaluate existing studies, reports and literature on

climate change analyses; climate models, and specific climate change scenarios relevant to theeastern Sierra Nevada; use climate scenarios and downscaling to evaluate impacts on the LAA

watershed; analyze impacts to LAA operations; provide adaptation measures, especially

groundwater storage at specific aquifer sites; and examine water quality implications of climatechange on water delivered from the LAA and recommend potential changes to operations and

treatment. This study is expected to be published by the end of 2010. LADWP, in collaboration

with other City departments, is also working with the University of California - Los Angeles on adownscaling GCM study for the geographic boundaries of the City of LA. LADWP is

particularly interested in investigating the climate change impacts on demands, groundwater

contaminants, and maybe the potential groundwater recharge.

Design

The design criteria referred to in this section are used for sizing of conveyance, treatment,

pumping, pipeline, and storage facilities. The following details have been obtained from casestudy discussions and survey results from LADWP.

Design Criteri a. Generally, LADWP relies on USEPA, State of California, and the City

of Los Angeles guidance documents and regulations for their facility designs. Design of facilitiesat LADWP is driven by water quality regulations. Design is mostly done in-house. However,

LADWP has started to use peer reviews or value engineering on their design projects, but the

decision of using these processes was not driven by climate change effects.Currently, LADWP has not performed an assessment of climate change impacts on their

design criteria and climate change is not a focus of their design practices. LADWP indicated that

reduced run-off, change in snowmelt, recharge, greater flood flows, and corrosion are significant

factors that could impact their design standards for facilities. LADWP currently believes that the

impacts of climate change may result in modifications of the design standards earlier thananticipated. Also, LADWP‟s water demand standards, such as peaking factors and facility sizing,

may be impacted. LADWP does not believe that the increased volatility and magnitudeassociated with climate conditions will have an impact on design standards in the near term.

LADWP uses different planning horizons depending on the type of facility. Typically, a 100-

year life cycle planning horizon is used for major pipelines and storage facilities. LADWP is notcurrently considering climate change in the planning process for their capital projects, although it

would be considered if climate change impacts were more certain. However, LADWP does focus

on low-impact buildings, as LEED buildings as a normal course of business under the City‟s

larger sustainability initiatives.LADWP indicated one of their main vulnerabilities to be the lack of storage along the

LAA. It is of most concern in case of early run-off and extreme storm events, as it may result inflooding/spilling. The consequences of spilling from LAA are a loss in ability to transfer water

and, hence, an added expense. Consequently, a significant risk from the lack of water storage isoversizing and overbuilding facilities. Further, the need for additional storage space may result in

a change how to design facilities as water will be transferred and consumed faster, without the

capability to spread it, resulting in higher costs.



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LADWP also anticipates that climate change may result in higher capital and operational costsfor their facilities. In addition, longer operation cycles may expose greater defects of materials

and equipment, more frequent replacement of materials and equipment, and more chemicals for

treatment may be needed.Consequences for Water Qual ity. No formal assessment has been performed on climate

change impacts on water quality. LADWP has specific concerns over temperature extremes, poor

water quality, and sea level rise on the impacts on water quality related design standards.

Reduced run-off, change in snowmelt, greater flood peaks, and increased erosion are moresecondary.

LADWP needs to comply with the USEPA and State‟s water quality standards. LADWP

is concerned with the possible need to comply with more standards because of climate changeimpacts, generating larger decision-making instead of smaller changes. LADWP is also

concerned with water quality in their storage tanks. With higher water temperatures, chloramines

may result in additional nitrification in summers. Also, LADWP believes that changes in naturalwatersheds, waterways, biota and the presence of non-native invasive species, such as Quagga

mussels may be associated with climate change.

Design Adaptation Strategies. LADWP‟s climate change adaptation needs f or their

design practices are varied. LADWP sees their biggest opportunities to incorporate climate

change into their design practices in Eastern Sierra watershed management, planning for the dryyears, justifying the design to match potential demand, and gaining support of the community for

future designs. LADWP believes that design flood and material allowed would all be moderately

impacted by climate change.To further enhance their compliance with the Surface Water Treatment Rule, LADWP‟s

nine out of 15 open distribution reservoirs containing treated water have been bypassed, replaced

by tanks, taken off-line, or protected with floating covers. Specific operations for some of thereservoirs, such as microfiltration and/or disinfection stations, were taken at some reservoirs to

treat reservoir water and achieve compliance. Improvements are underway to comply with the

six remaining open reservoirs in the future. LADWP believes the deterioration of water quality

in its reservoirs can be addressed by adding mixers to aerate and release water at different ages.

If state health requirements or design standards change due to warmer atmospheric temperatures,LADWP foresees the potential need to add more mixers, decrease the size of reservoirs, add

more reservoirs, increase the storage capacity of the LAA, and optimize reservoir spacemanagement.

While the implementation of the aforementioned adaptation strategies are not driven

solely by climate change, LADWP is interested in future research on water quality and especiallythe possible need to change disinfection chemicals if current ones are deemed less effective in

future years. LADWP also feels that regulatory support would be necessary to implement these

changes in design practices and ease adaptation to climate change.

Watershed and Environmental

Watershed protection and environmental regulatory functions at LADWP could also bevulnerable to climate change. This section covers potential climate change impacts on

LADWP‟s watershed and environmental requirements and adaptive strategies to incorporate

climate change into watershed and environmental areas.



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Watershed Protection and Environmental Regulatory Functions. LADWP expressedconcern over climate vulnerabilities with respect to the limited amount of water available from

their watershed and the need to mitigate environmental projects. This may be a high concern in

the future because water allocations from MWD may also decrease. Environmental mitigation

projects include the State Water Resources Control Board Mono Lake Decision, which permanently limited LADWP‟s ability to export water from the Mono Basin and required the

restoration of the streams feeding Mono Lake and restoration of Mono Lake; implementation of

the Owens Lake Dust Mitigation Project; rewatering the Lower Owens River and a number ofother environmental restoration projects in the Owens Valley that require water.

LADWP anticipates the following issues related to mitigation projects may worsen due to

climate change and to create more challenging conditions for yield supply: more stringent pumping limitation at Owen‟s Valley to preserve habitat, increased flash flooding in the

watershed, increased waste and debris in source water, damage to facilities, maintenance of

habitat conditions for various species present in the watershed and in ecosystems along the LAA,and the addition of more requirements to the existing mitigation. In addition to these technical

issues, LADWP noted political issues are associated with watershed protection. One example is

dust mitigation at Owen‟s Lake where difficulties with permitting challenges for LADWP to

offer “dry” or water efficient dust mitigation measures because the permits require to use water

to provide habitat for shorebirds. Climate change regulation causes limitations and/or reductionsof GHG emission, which may also impact environmental and mitigation projects.

Another concern for LADWP‟s watershed protection is their limited storage capacity

because less recharge is anticipated due to more precipitation falling as rain instead of snow inthe Eastern Sierras, which creates more potential for flash flooding. The Antelope Valley

groundwater adjudication may present LADWP an opportunity to divert water from the LAA for

groundwater storage, but diverting significant volumes of water at once is a challenge forLADWP because of the current lack of infrastructure.

LADWP anticipates being faced with invasive species issues. Plants in the watershed

range from grassy types to more woody types. No maintenance fires are allowed so there is an

increase in brush, which in turn requires more water to be maintained decreasing water supply

available.Watershed Protection and Environmental Regulatory Adaptation Strategies. As

described above, there are several concerns associated with watershed protection andenvironmental regulatory functions. LADWP believes that climate change impacts will

exacerbate these concerns.

Adaptation strategies considered are mainly the development of alternative watersupplies. Examples include evaluating groundwater usage at Owen‟s Lake; finding additional

groundwater storage areas; cleaning up San Fernando Valley contamination; developing green

streets by capturing storm water runoff and storing it in spreading grounds; and implementing

conservation and reclamation.

Key Observations

This section summarizes the main points from LADWP‟s climate change approach andtheir challenges on the path to adapt to climate change (Table 4).



16

Table 4

Key observations for LADWP

LADWP Policy Planning Design

Climate Change

Approach

City of LA long-termwater supply policy

in place to sustain a

reliable water supplywhile meeting current

and future demand.

No development of

new importedsources.

City of LA‟s

mitigation-focused policy related the

GHG and

participation to theMayor‟s Climate

Action Plan.

Additional

organizational needs.

Multi-department

collaboration for

Integrated Resources

Plan, efficient

landscaping, andconservation.

Development of pricing programs

incorporating climate

change. Securefunding mechanisms

for conservation and

recycling.

No recent assessmentof existing water

supply planning

criteria.

Evaluation of water

resources planning

efforts on continual basis to take into

account changing

conditions and

dynamic water supplysituation impacting

the City‟s water

supplies.

Providing near-term

reliability for long-term water supply

planning.

Yearly predictions of

LAA operation

criteria. Need to

increase LAA storage

capacity.

Monitoring of

impacts of watersource areas (Eastern

Sierra, Bay Area

Delta).

Involvement in

several research projects and

collaborative partnerships:

Study in progress toevaluate and develop

proposed adaptation

measures to addressclimate change.

No currentassessment of climate

change impacts on

design criteria performed.

Modifications of

design standards inthe future. Increased

volatility and

magnitude associated

with climate changeconditions not

impacting design

standards.

No consideration of

climate change in planning process for

capital projects.

Need to design for

additional storage.

Need to plan for

greater capital and

operational costs dueto longer operational

cycles.

Additional

nitrification in tanks

and reservoirs due tohigher water

temperatures.

(continued)



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Downscaling GCM

study with UCLA in

progress.

Adaptation

Challenges

Need to understand

the magnitude andgravity of source

impacts anduncertainties before

creating adapting

policies to addressclimate change.

State legislation may

increase water feesand impede investing

in improvements.Shift mitigation-focused GHG policy

towards adaptation-

focused.

Changes to demand

planning modeling toinclude economic

projections andmodify model

assumptions.

Study of potential

actions to adapt to

future changing

conditions. OutlineLAA potential

operational impactsand understanding ofclimate change

impacts to the Eastern

Sierras.

Expansion of existing

supply source and

diversification ofsources with no new

imported sources.

Development of

conservation and

pricing management

programs.

Integration of climate

change in demandand supply forecasts.

Washing out LAA,

expanding LAAcongested areas,

clearing out debris

from LAA,developing watershed

programs to address

Need for more

research on waterquality uncertainties

Potential need for

increased water

quality compliance.

Gaining support of

the community for

future designs.

Development ofadditionalinfrastructure for

storm water capture,

additional storagespace, additional

treatment compliance,

additional equipment

for water qualityimprovement.

Development ofregulatory support to

help with adaptation.

(continued)

(continued)



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greater flow peaks.

Investigation ofclimate change

impacts to demand

factor, water qualityof the LAA and

groundwater

contaminants and

potential groundwaterrecharge.