May 18, 2001
BACKGROUND
A. Plan B
On March 28, 1997, California-American Water Company (Cal-Am)
filed application A.97-03-052 with the California Public Utilities
Commission (CPUC) for authority to construct and operate the Carmel
River Dam and Reservoir Project (CRDRP).
The CPUC issued Decision D.98-08-036 requiring Cal-Am to
prepare a long-term water supply contingency plan describing the
program or combination of programs that the company would pursue if
for any reason the Carmel River Dam Project did not go forward. Assembly Bill 1182
subsequently required the CPUC itself to prepare a water supply
contingency plan. This contingency plan is
informally referred to as Plan B.
The CPUC retained a consulting team (Plan B Team) to develop Plan B. The Plan B Team laid out a series of steps to develop Plan B, soliciting public input at each step. Five potential water supply technologies, or components, were identified and are currently being assessed for their ability to provide the required 10,730 acre-feet per year (afy) Plan B water supply. The final recommended Plan B configuration will likely contain a package of components.
B. Prior Steps in the Plan B Process
The
Plan B Team has completed several steps in the Plan B analysis and
issued reports at each step of the process.
The reports have presented planning goals and objectives of
Plan B (December 1999), a characterization of components to be
considered (April 2000), and an initial screening of components
(November 2000). The last public meeting was
held in Seaside on December 13, 2000 to review the initial screening
results and solicit public input.
Since the meeting, the Plan B Team has conducted more in-depth
analyses of the most promising components to determine what
combination could potentially provide the 10,730-afy water supply.
C. Purpose and Structure of this Memorandum
This
memo is a progress report to inform the public of the status of Plan
B development, including ongoing studies and next steps. It briefly describes each
component currently being considered and the estimated range of yield
that that component could contribute to the total 10,730-afy
requirement. Based on this second phase of analysis and the
public input from the December meeting, it is anticipated that the
final recommended Plan B contingency plan package will consist of a
combination of aquifer storage and recovery (ASR) and desalination,
with some yield from water rights, if approved, and reclamation.
Comments
on this memo are being solicited from the public and will be
considered in the final Plan B report.
On May 31, 2001 representatives from the Plan B Team and the
CPUC will attend the Monterey Peninsula Water
Management District (MPWMD) Board public meeting to present a brief
summary and next steps. A
final Plan B document will be produced and distributed in the
July/August time period.
II. Updated Assessment of the Target Yield and Ranges of Plan B Components
A. Updated Assessment
This
section of the memorandum presents the Plan B Team's updated
assessment of the potential yield of Plan B components.
The components examined include conservation, reclamation,
water rights, aquifer storage and recovery (ASR), and desalination. The ranges of potential yield have been
established to allow maximum flexibility in meeting Plan B’s
10,730-afy yield requirement. The
November 2000 Component Screening Report prepared by the Plan B Team
included a proposed mix of components that could make up the
10,730-afy Plan B water supply. The following paragraphs
describe a refined forecast of potential yield from each component
and a proposed range and target size for the components.
These are summarized in the table below.
Summary
of Component Yield Range for Plan B Strategy (afy)
Component |
Screening Report Proposal (November '00) |
Component Yield (April, '01) |
Component Yield (April, '01) |
Refined Target Yield (April, '01) |
|
Conservation |
|
|
|
|
|
Reclamation |
|
|
|
|
|
Water
Rights |
|
|
|
|
|
Seaside
Basin ASR |
|
|
|
|
|
Desalination |
|
|
|
|
|
Total |
|
|
|
|
The
refined ranges and their supporting rationale are described in the
paragraphs that follow.
B. Conservation
The
MPWMD and Cal-Am have been operating a water conservation program for
many years. Cal-Am
customer per capita water use is among the lowest in urban areas in
the State. The program includes public
education, rebates for low flow toilet replacement, expanded customer
water conservation, and standby rationing plans.
Due to the duration and achievements of this plan, it is the
Plan B Team's assessment that additional consumer conservation is
unlikely to produce additional efficiencies to contribute to
long-term yield of water. What consumer conservation
can be achieved will be called upon for specific drought related
supply shortfall events.
Cal-Am
has also completed an audit of its existing distribution system to
identify areas of high system leakage.
Cal-Am is currently replacing older mains to reduce system
leakage and unaccounted-for-water (UAW).
Cal-Am reports that its UAW is less than typical for systems
of similar type and age. In
1995, Cal-Am’s transmission and distribution losses were only
4%. It is unlikely that a
long-term yield of water can be realized through further reduction of
the UAW in the system. As
the system continues to age, replacement programs will only maintain
the UAW at its current levels. Due
to these conditions, the target yield from conservation is zero.
C. Reclamation/Urban Water Recycling
There are two potential sources of reliable
reclaimed water available to replace existing potable supplies
currently provided by Cal-Am. The Carmel Area Wastewater
District/Pebble Beach Community Services District (CAWD/PBCSD)
reclaimed water project expansion and the Salinas Valley Reclamation
Project (SVRP) reclaimed water expansion both could replace existing
potable water use by Cal-Am customers if implemented by their
sponsors.
The Plan B Team has met with both the CAWD and
the Marina Coast Water District (MCWD) to gather information about
their ongoing recycled water development projects.
A draft recycled water development program has been prepared
for review by the agencies. After
the agency review comments have been incorporated into the
development program, an implementation plan will be developed for
Plan B to pursue development of the recycled water projects.
It is intended that this implementation plan be carried
forward by the MPWMD.
For the purposes of Plan B strategy development,
it is assumed that up to 1,000-afy of reclaimed water use (500-afy
from CAWD/PBCSD expansion and 500-afy from SVRP expansion) could
reduce the 10,730-afy Plan B yield requirement.
This represents the maximum potential yield from reclamation. The minimum yield is zero, which represents the
scenario where neither project is able to offset Cal-Am potable water
demand. The target yield should be
1,000-afy, which represents an aggressive but responsible goal for
reclaimed water development. The
two responsible recycled water purveyors are currently refining these
estimates of recycled water development.
D. Water Rights
Cal-Am or the MPWMD could get additional water
rights for direct diversion from the Carmel River if the State Water
Resources Control Board (SWRCB) determines that there would not be a
negative effect on the environment and that it is in the community’s
best interest to do so. This
is an ongoing process that is currently on hold until a decision is
reached on the water supply for the greater Monterey Peninsula area.
Up to 7,900-afy of additional water rights could be granted to
the MPWMD or Cal-Am, based on recent applications to the SWRCB by the
MPWMD. This represents the maximum
potential yield from additional water rights.
The minimum potential additional water right would be zero if
the water rights process were tied up in litigation over the
foreseeable future. The target yield is set at
3,000-afy, representing a less optimistic view of potential water
rights that could be granted by the SWRCB.
E. Seaside Basin Aquifer Storage and Recovery (ASR)
A 1999 report
prepared for the MPWMD by Fugro West estimated 7,200 acre-feet of
storage was available through ASR operations in the Seaside
groundwater basin. This estimate was based on the historic draw
down of groundwater levels since the 1950s for an aquifer bounded on
the east by General Jim Moore Boulevard. Based on this
information, the Plan B Team's assessment was that a reasonable
maximum ASR component size would be approximately 50 percent of the
available storage, or 3,600-afy. (Safe annual yield is
typically approximately half of the total available storage volume
because of the need to carry over storage for drought reserve.)
Basin yield is being reinvestigated and the geographic
limitations of the basin that were initially understood are no longer
present. Recent investigations suggest that the basin storage
is significantly in excess of 7,200 af.
Carmel
Valley Simulation Model (CVSIM) runs have been completed to
determine the timing and availability of excess winter flows in the
Carmel River after meeting minimum instream flow requirements for
fisheries. This information has been used to establish the
long-term yield for an ASR project (based on the
hydrologic record) given the level of flow routed from
Carmel Valley to the Seaside area in distribution system
hydraulic model analyses. The flow also is the basis for
sizing diversion, treatment, and conveyance facilities. Test well data are promising. The MPWMD test
well at Fort Ord is being outfitted for 1,500-gpm injection and
3,000-gpm extraction (limited by the electricity available at the
site). A conservative estimate of the data indicates that
2,000-gpm injection and 4,000-gpm extraction can be
accommodated. The current constraint to ASR development is now
considered to be the water diversion, treatment, and
conveyance infrastructure (from Carmel Valley to the Seaside Basin)
and the costs of new diversion, treatment, and
conveyance facilities.
The
Plan B Team has conducted winter and summer hydraulic analyses
of the Cal-Am water distribution system for ASR operation and
confirmed the minimum initial phase yield of 3,000-afy for this
component. This minimum level of ASR represents the average
yield constrained by use of the existing Cal-Am distribution system
to route excess Carmel River flows, generally from December to May,
to the Seaside Basin injection and extraction wells. The
maximum yield is approximately 6,050 afy. The target Seaside
Basin ASR component size is 3,730-afy. This could be modified
as needed based on the cost optimization work currently being
performed for the Plan B strategy development.
The Plan B Team is
continuing with the distribution system hydraulic analyses to size
ASR and desalination conveyance facilities and will review the
results of the hydraulic analysis with Cal-Am. The Plan B Team
also met with representatives from the Cities of Seaside and Del Rey
Oaks and discussed siting constraints for ASR facilities.
The Plan B Team is continuing its evaluation of Seaside Basin
ASR well locations and sizes, and the groundwater basin
hydro-geologic characteristics. In addition, ASR would require
additional water rights for diversion of winter flows to storage.
A comprehensive
review of ASR program feasibility is being performed and will be
incorporated into Plan B. The feasibility study includes a data
review of Carmel River flows and diversions, Seaside groundwater
basin hydro-geologic characteristics, identification of missing or
insufficient data, and development of a conceptual design for the ASR
well system facilities. This analysis will be completed in time
for inclusion in the final Plan B document, scheduled for Fall 2001.
F. Desalination
Desalination could
potentially provide the entire Plan B water supply because of the
readily available and reliable seawater source.
However, a large desalination facility would be implemented
only if all other Plan B strategy components failed in their
implementation or fell short of their target yields.
The minimum desalination facility is based on a single 3-mgd
reverse osmosis process module, which is equivalent to a 3,000-afy
supply. The phased implementation of a desalination component
could add capacity in 3-mgd increments up to that needed to meet the
Plan B water supply goal. The
proposed target is 3,000-afy, which is approximately 3-mgd assuming
full production at 90% availability. This could be expanded to
an installed capacity of 6-mgd (two 3-mgd modules). Any additional
capacity above that required for Plan B could be used for
peaking during summer months, as a standby source, and to provide
additional drought resistant supply. The target size will be
modified as needed based on desalination cost optimization work
currently being performed for the Plan B strategy development.
The
Plan B Team has studied the area from Moss Landing to Monterey for
potential sites. Local city and state agencies were consulted
about the possibility of building desalination facilities at various
sites. A feasibility-level geologic and geotechnical evaluation
of the sites has been completed, along with a Phase I environmental
site assessment. Several feasible desalination facility sites
were identified; however, final site selection will be done after
completion of the environmental documentation for the desalination
plant.
Specific design
parameters for seawater production wells and brine disposal wells are
currently being investigated. The desalination process design
development has been completed. Some of the desalination
technologies reviewed included multi-stage flash distillation,
multiple effect-distillation, vapor compression, and reverse osmosis.
The recommended technology for Plan B is reverse
osmosis. Preliminary design criteria and process flow diagrams
have been developed for a reverse osmosis system. Conceptual
facility layouts and capital, operating and maintenance cost
estimates have been prepared. A 3-mgd desalination plant
requires approximately two megawatts of electricity to operate the reverse osmosis
system. A larger plant would require a proportional increase in
energy. These large power needs must be considered in
evaluating the economics of a desalination facility. The high
power consumption would likely require modifications to the local
electrical grid. Consultation with the local power
agency should be initiated in the design phase of the
project.
G. Managing Operational Yields
Cal-Am
and MPWMD will need to continue managing the ongoing operational
yield of the existing reservoirs.
For example, the MPWMD is exploring the feasibility of
dredging the two existing reservoirs on the Carmel River, the San
Clemente Reservoir and the Los Padres Reservoir.
The storage capacities of the reservoirs have been
significantly reduced due to sediment deposition over the past eight
decades. Sediment
management at both reservoirs, whether by dredging or other means,
has become increasingly important due to potential effects on aquatic
life and downstream flood elevations.
A
recent MPWMD issue paper found that sediment removal from the
reservoirs is technically feasible, but could result in potential
significant adverse impacts to people, aquatic resources, and
wildlife. The high cost of dredging may be partially offset
by marketing the dredged materials.
More information is needed on the characteristics and volume
of dredged materials at both reservoir sites, as well as further
information on the effects of existing regulations, such as the
Endangered Species Act, before a definitive determination can be made
on the feasibility of dredging in the Carmel River (MPWMD 2000).
Currently,
a draft EIR for the seismic retrofit of the San Clemente Dam is
available for public review. One
of the principal concepts being addressed by Cal-Am and its
consultants is the construction of gated sluiceways through the dam
below the spillway to allow sediment in the reservoir to be sluiced
downstream during periods of high winter flows.
The preferred alternative would remove sediment from the San
Clemente Reservoir and maintain an additional 250-300 af of
operational storage. The additional storage would be used to provide
sediment management opportunities and would increase flexibility to
release flows for fish in the dry season.
It would help Cal-Am maintain operational flexibility for
surface water diversions into the distribution system.
Although the additional storage may provide some increased
yield, the volume would be insufficient to provide substantial dry
year carryover storage and cannot be relied on as a firm yield for
Plan B purposes.
Other
proposals have been suggested. The
California Coastal Conservancy has recommended partial dam removal
and burial by relocation of sediment.
The National Marine Fisheries Service has recommended dam
removal with no dredging. The
State Department of Water Resources, Division of Safety of Dams,
intends to make a decision on the preferred option in July 2001.
A revised draft EIR is likely to be prepared and circulated
again for public comment.
III. NEXT STEPS IN THE PLAN B PROCESS
As indicated
above, analysis of the optimal configuration and phasing of Plan B
components is ongoing and will be completed in the near future. The proposed Plan B preferred alternative will be
presented in the July/August timeframe.
Following completion of this phase of the process, Plan B will
be evaluated relative to the proposed Carmel River Dam and the No
Project alternatives. Tentatively,
the schedule for completing the study is as follows:
May
31, 7pm: Public Briefing to Monterey Peninsula Water Management
District Board
Monterey City Council Chambers, Madison & Pacific Streets, Monterey.
June
15: End of Comment Period on Plan B Components Status Report
July/August:
CPUC Issues Revised Plan B Document
August/September:
Public Meeting on Revised Plan B Document
September/October:
CPUC Delivers Plan B to MPWMD
October/November:
MPWMD Initiates CEQA Review Period
Comments Invited
Your comments on
this Status Report on Plan B Components are invited and will be
considered by the project team in drafting the final Plan B. They may be forwarded to:
Richard Tom, Project Manager
Water Division
California Public Utilities Commission
505 Van Ness Avenue
San Francisco, CA 94102
Comments are due by
June 15, 2001.
This 1,000-afy target may be too aggressive but the Plan B Team recommends an aggressive approach to reclamation. If the target is not met, the remainder could be met by another component.
Based on MPWMD News Release, May 1, 2001, “Water District to Apply for Water Rights.”