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Date:   August 27, 2009
To:     Kathleen Van Velsor, ABAG Climate Change Team
From:   Kristian Ongoco, Planning Intern
Re:     Implications for Future Water Supply to Delta-supplied Counties with
        Priority Development Areas


________________________________________________________________________


The Association of Bay Area Governments (ABAG) have to date adopted 65 Priority
Development Areas (PDA)1, including three new PDAs, which were approved at the
beginning of this month. The Climate Change Team’s recent work has involved
examining various options for the future of the Sacramento-San Joaquin Delta and
its surrounding areas. Along with delivering water to the Central Valley and
Southern California, five Bay Area counties rely on the Delta for water supply. These
counties are where some of the fastest growing PDAs are located, e.g. Cities of
Oakley and Pleasanton – making it a critical issue for ABAG2. Counties directly
impacted by the Delta’s water delivery are Alameda, Contra Costa, Napa, Santa
Clara, and Sonoma Counties (See Figure-1). Several water districts and over forty
departments serve these affected areas3.


Delta-PDA Water Supply Assessment

In 1983, California passed the Urban Water Management Planning Act. The act
mandates that every water supplier that provides water to 3,000 customers or
more, or provides water to over 3,000 acre-feet of water annually, adopt and
implement an Urban Water Management Plan4. Plans must cover water reliability,
supply, and demand in normal, dry, and multiple dry years, demonstrating that
future supply will meet future use.

The Delta-PDA Water Supply Assessment is a preliminary look into what the future
of water use holds for these affected PDAs and how transformation in the Delta may
impact water use. By comparing water distribution, land use, current use, projected
demand, and population projections in the affected areas, ABAG can determine the
Delta’s state of water delivery to these areas.

1
  Priority Development Areas (PDAs) are locally-identified, infill development opportunity areas
within existing communities.
2 ABAG, What If? Projections 2009
3
  ABAG, Water retail Agencies Map
4 California Water Code Sections (10610 - 10656)
Figure – 1




_________________________________________________________________________________________________

Figure – 1 illustrates the areas served by the Delta.
Figure - 2




       _________________________________________________________________________________________

Downtown Hayward (Figure – 2) is an example of a PDA within the Delta water
service area. As an example, the City of Hayward’s demand, land use, and
projections have been extracted from this assessment to compare these as variables.
Since Hayward publishes its own Urban Water Management Plan, the figures may be
more exact than if aggregated with many other jurisdictions in a water district-wide
UWMP. Three PDA’s lie in the City of Hayward: Downtown (shown in Figure-2),
South Hayward BART Station, and The Cannery.
Below is a summary of Hayward’s PDA and city population.
Population5
                                 2005         2030___                     Change
Downtown Hayward                 2,936        7,306                       +4,370
South Hayward BART Station       1,288        2,630                       +1342
The Cannery                      41           272                         +230
City of Hayward
Total Population                 144,300      174,800                     +30,500

Figure-3


                       City of Hayward Population Projections

                    190,000

                    180,000

                    170,000
       Population




                    160,000

                    150,000

                    140,000

                    130,000

                    120,000
                              2005   2010   2015   2020     2025   2030
                                               Year




Figure 3 illustrates a steady increase in population from 2010 to 2030, with an
aggregate rise of 30,500 people by 2030. Growth within the PDA’s represents
approximately 20% of the anticipated growth for the city.




5
    City and PDA population projections, ABAG, Projections 2009
Water Demand Projections

In general, water demand forecasts are based on current demographic projections.
Local Urban Water Management Plans population projections are often derived
from ABAG, and are manipulated with historic and current water demand.



Figure-4


                                       City of Hayward Water Use

                35,000

                30,000

                25,000
    Acre/Feet




                20,000
                                                                               Acre/Feet
                15,000

                10,000

                 5,000


                    0
                         2005   2010        2015          2020   2025   2030
                                                   Year

Source: City of Hayward, Urban Water Management Plan, 2005

According to the chart above, water demand in a normal year will increase by
approximately 10,000 acre/feet over a 25 year period.
Figure-5


                            City of Hayward Actual and Projected
                                Population and Water Demand
                250,000



                200,000
   Population




                150,000                                                    Acre/Feet
                                                                           Population

                100,000



                 50,000



                     0
                     2005   2010      2015          2020     2025   2030
                                             Year

Source: City of Hayward, Urban Water Management Plan, 2005

Figure-5 shows the relationship between population projections and water demand
forecasts, with water demand increasing as population increases.




 A Hayward population rise of 30,500, or 21% in twenty-five years is
 moderate. However, according to ABAG Population Projections, in faster
 growing cities like Dublin, the population is expected to almost double in
 this timeframe.
Figure - 6


                               City of Dublin Actual and Projected
                                 Population and Water Demand

                 120,000


                 100,000


                  80,000
    Population




                                                                                            Water Demand
                  60,000
                                                                                            Population

                  40,000


                  20,000


                      0
                      2005   2010         2015          2020         2025         2030
                                                 Year

Source: Dublin/San Ramon Services District, Urban Water Management Plan, 2005



In 2005, Dublin water supplier Dublin and San Ramon Services District (DSRSD)
projected Dublin’s population to reach 56,117 by 2030. ABAG’s 2009 report
forecasts Dublin to have a populace of 49,000 by 2010; 56,000 by 2015; and 76,600
by 2030. This significant disparity will force the water supplier to adjust its water
demand and supply forecast, and more accurately account for future water need.
The adjustment also adds to the impact of California’s Delta crisis6, as “the
uncertainty about the reliability of water supply has thrown the hard work of cities
and other land use planning agencies into chaos7.”

Water demand in many urban water plans for the Bay Area show that water supply
meets demand for a normal year, but a single dry year within a twenty year period
can alter this scenario, shown below. Conservation efforts will also affect future
water supply and demand8.



6
  Public Policy Institute of California, Envisioning Futures for the Sacramento-San Joaquin Delta, February
2007
7
  Letter in Response to Preparation and Notice of Intent to Prepare EIR/EIS for Bay Delta Conservation
Plan from Dublin and San Ramon Services District, dated May 29, 2008
8
  City of Hayward, Urban Water Management Plan, 2005, 5-5
Figure – 7


                                       Water Supply and Demand
                                        Single Dry Year within a
                                          Twenty-year period

                            Water reduction or supply increases necessary by 2030

                     30

                     25

                     20
        Population




                                                                                           Demand
                     15
                                                                                           Supply
                     10

                     5

                     0
                          2010       2015         2020         2025         2030
                                                  Year

Source: City of Hayward, Urban Management Plan, 2005

Urban Water Management Plans are required to report water supply and demand
projections in normal, single, and multiple dry years. California, however, has
historically experienced multiple dry years, and water plans do not sufficiently
emphasize the frequency of multiple dry years, especially in relation to water
demand forecasts9.


Limitations

This Delta-PDA Water Assessment outlines the water demand, projections, and
water use for selected PDAs in a preliminary way, given limitations in obtaining
specific water demand information. This is due to the large number of suppliers and
districts, and a limited research time frame. For example, multiple PDAs are
supplied by large water suppliers such as East Bay Municipal Utility District
(EBMUD), which serves twenty incorporated cities and fifteen unincorporated
cities10. In these cases, it is difficult to compare current demand and future demand
since water plans generally do not allocate water amounts to specific cities or
service areas.



9
    California Water Resources Board, http://www.water.ca.gov/drought/assist/archive.cfm
10
    East Bay MUD, Urban Water Management Plan, 2005, 2-1
Moreover, all plans are not created equal. Urban Water Management Plans have
required water projections, but some plans include detailed information on specific
cities, land use, and consistent methodologies, while others do not. The
methodology for projected water demands (for instance by EBMUD) relied on the
development of a spatial geographic information system (GIS) land use database,
and the determination of land use unit demands (LUDs) in gallons per day per acre
(gpd/ac). These data were then applied to acreages of land uses11.

Finally, this assessment was predicated on 2005 Urban Water Management plans –
information that is five to seven years old, and the base year of the population
projections will alter the projected water demand. For example, the recent
economic recession has caused decreases in population and jobs in some areas of
the region, arguably making the projections unreliable. A more accurate
assessment would include data from upcoming 2010 UWM plans, which will be
submitted next year.

Findings

Policy and planning implications of analyzing the projected water demand and
population in the Delta-PDA areas are as follows:

         This is the third straight dry year for these Delta-supplied counties.
          Therefore, water plans should emphasize the potential impact of multiple
          future dry years on their ability to deliver water to communities and
          developments.
         Delta-supplied counties and their cities appear to be most vulnerable to a
          lack of water supply in the next twenty-five years due to natural and
          manmade hazards -- especially in the fastest growing cities and
          redevelopment areas of the Bay Area.
         The 2005 Urban Water Management Plans for the City of Hayward and San
          Ramon and Dublin Water Services demonstrate that supply can meet
          demand. However, recent forecasts indicate higher population figures in the
          Bay Area than what the four-year old plans report. Thus, modifications in
          conservation levels and water supply and demand must change accordingly.
         Urban water management plans need a more detailed break down of specific
          areas and sources, so that planners can more accurately plan for a growing
          population in redeveloped areas.




11
     East Bay MUD, WSMP 2040, 7-1

				
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