San Luis Reservoir Low Point Improvement Project Draft

Transcription

Preface
SCVWD has prepared this report to summarize results to date from the planning process
now underway for the San Luis Reservoir Low-Point Improvement Project. It
• describes the low-point problem and its effects on the quality and availability of
water delivered to users who depend on the reservoir for domestic, industrial, and
agricultural supply;
• summarizes the alternatives development and screening process conducted to date;
and
• provides information on the outreach process that has enabled SCVWD to incorporate
public and resource agency input into the project process so far.
SCVWD is currently slightly more than a year into a planning and study process expected to last about three years. Next steps include further development of project
alternatives and preparation of an environmental impact report/environmental impact
statement analyzing feasible project alternatives in more detail. This report also
provides information on the timetable and approach anticipated for these upcoming
phases of the project.
We welcome your input on the project and on this report, and would be happy to address any questions you may have. Please direct comments and inquiries to
Kurt Arends, P.E., Senior Project Manager
Santa Clara Valley Water District
5750 Almaden Expressway
San Jose, CA 95118-3614
Telephone: (408) 265-2600
Email: [email protected]
Additional information on the Low-Point Improvement Project may be obtained from the
San Luis Reservoir Low Point page on the SCVWD web site (www.valleywater.org).
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San Luis Reservoir Low-Point Improvement Project
Draft Alternatives Screening Report
Table of Contents
Page
Section 1 – San Luis Reservoir and the Low-Point Problem................................... 1
Section 2 – The Alternatives Development and Screening Process ......................... 9
Section 3 – Outreach Activities ....................................................................... 19
Section 4 – Results of Alternatives Screening .................................................... 23
Section 5 – Feasible Alternatives Recommended for Further Consideration.............. 31
Section 6 – Next Steps ................................................................................... 37
List of Acronyms
Exhibits (included at end of report)
I – Level I Screening Matrix
II – Alternatives Location Map
Section 1
San Luis Reservoir and the Low-Point Problem
Jointly owned and operated by the U.S. Bureau of Reclamation and the California Department of Water Resources, San Luis Reservoir is one of California’s largest reservoirs
and a key component of the state’s water supply system. In fact, with a capacity of
more than 2 million acre-feet (AF), it is the largest offstream storage facility in the
world.
Water from California’s Sacramento–San Joaquin Delta is
delivered to San Luis Reservoir
via the California Aqueduct and
Delta-Mendota Canal for temporary storage during the rainy
season. During the dry season, ��
this stored water is released for ��
use by contractors of the State ��
Water Project (SWP) and the
federal Central Valley Project (CVP)
located south of the Sacramento–San
Joaquin Delta.
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San Luis Reservoir also provides water to the
Santa Clara Valley Water District (SCVWD) and the
San Benito County Water District (SBCWD). Water is delivered to these users through
the CVP’s San Felipe Division on the west side of the reservoir. In the near future,
the Pajaro Valley Water Management Agency (PVWMA) is also
expected to draw from San
Luis Reservoir via the San
Felipe Division. Other
“south of Delta” users
receive water through the
William R. Gianelli Pumping-Generating Plant on
the east side of the reservoir.
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See end of this report for a list of
acronyms and abbreviations.
Section 1
The Low-Point Problem
At present, when San Luis Reservoir approaches its late summer–early fall low
point, operational constraints combine with the design of existing facilities to
limit the flexibility of other federal and state contractors to fully utilize reservoir
storage. The low-point problem poses a threat to about half of the imported CVP
supplies for the San Felipe Division agencies. The following sections describe this
low-point problem in more detail.
Annual Operational Cycle
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San Luis Reservoir Water Seasonal Storage
The annual operational cycle
of San Luis Reservoir entails
filling the reservoir during the
fall and winter and releasing
the stored water during the
spring and summer, as shown
in the graph on the left. Water
levels in the reservoir typically
reach their annual low point
in late summer or early fall,
when contractors’ water demands are at their peak. The
elevation of the water surface
at the low point depends on a
number of factors, including
• yearly rain and snowfall in tributary watersheds,
• demands of state and federal contractors,
• volume of water exported from the Sacramento–San Joaquin Delta, and
• operational decisions made by the CVP and SWP.
Accurate predictions of the low point’s timing and severity each year are key to
the planning necessary to maintain operational flexibility and reliability for the
CVP and SWP.
As Water Level Drops …
The low point begins to affect San Felipe Division operations when
water level in the reservoir drops to an elevation of about 406 feet above mean sea
level, corresponding to a storage capacity
of about 571 thousand acre-feet (TAF). At
this elevation, summer algal growth that
develops at the reservoir’s surface and
extends to depths of 30 feet or more may
begin to be drawn into the upper intake of
Section 1
the Pacheco Pumping Plant, located at elevation 376. Consequently, when the water
level approaches elevation 406, the upper Pacheco intake is shut off manually to
avoid adverse effects on the quality of San Felipe Division water supply. When the
water level reaches the "low-point" at approximately elevation 369, corresponding to about 300 TAF capacity, algae may begin to enter the lower Pacheco intake
located at elevation 334. At these lower water levels, the concentration of algae
in water drawn into the Pacheco Pumping Plant may be so high that the water is
untreatable, and water supply may be interrupted as a result of poor water quality.
Even without algal growth, if the water level were to drop below the elevation of
the lower Pacheco Intake, water could not be drawn into the Pacheco Pumping
Plant, and no supply would be available to the San Felipe Division. As shown in
the schematic below, the Gianelli inlet/outlet is at a lower elevation (273–296),
so it is not affected by algal growth as long as reservoir drawdown is limited to
maintain water levels at the elevation of the lower Pacheco intake.
El. 554'
El. 545'
Close Upper Intake
El. 406'/571 TAF
3
To
San Felipe
Division
Capacity 2.0 MAF
Sisk
Dam
El. 635'
Pacheco
Pumping
Plant
Gianelli
Intake
Crest
Pacheco
Regulating Tank
Seasonal Algal
Growth Shown
at "Low Point"
Upper Intake
El. 376'/345 TAF
"Low Point"
El. 369'/300 TAF
Inactive Conservation Pool
El. 326'/79 TAF
Top of Lower Intake
El. 334'/110 TAF
To CVP/SWP
Contractors
Top of Intake
Pacheco
Tunnel Reach 1
El. 296'
Bottom of Intake
El. 273'
Schematic Cross Section View of San Luis Reservoir, Looking South
In response to the low-point problem, reservoir operators now manage San Luis
Reservoir to maintain water levels above the low-point elevation of 369; as a result,
approximately 200 TAF of water stored in the reservoir remains unavailable to state
and federal users each year. This problem is expected to worsen in coming years as
pressure to use all of the water stored in the reservoir increases and new measures
for environmental and fish habitat protection further restrict the amount of water
that can be exported from the Delta for storage in San Luis Reservoir.
Local Impacts
While all contractors of the CVP and SWP are impacted by the low point, it presents
a particularly challenging situation for the CVP’s San Felipe Division contractors,
because San Luis Reservoir is their only source of CVP water. Other CVP contractors,
and all of the SWP contractors, may still receive water supply via the CVP and SWP
canals even if supply from the reservoir is inaccessible.
Section 1
Potential effects of the low-point problem include the following.
• Interruption of water deliveries to domestic, industrial and agricultural users.
• Interruption of water deliveries used to replenish groundwater supplies.
• Clogging of agricultural irrigation systems.
• Reduced ability to treat water efficiently.
• Increased water treatment costs.
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• Taste and odor problems.
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Monthly Demand, San Felipe Division
Statewide Impacts
The low-point problem restricts the operational flexibility of San Luis Reservoir for
all CVP and SWP contractors south of the Sacramento–San Joaquin Delta. The need
to maintain the water level in the reservoir at or above about 300 TAF to meet San
Felipe Division allocations restricts reservoir operators’ ability to fully utilize the
Section 1
available storage in San Luis Reservoir. As a result, water supply to south of Delta
contractors from San Luis Reservoir is effectively reduced.
The timing and rate of drawdown of San Luis Reservoir is also important for flexible
operations of the CVP and SWP. For dam safety, USBR has established a maximum
drawdown rate of 2 feet per day from San Luis Reservoir. The effect of this maximum
drawdown rate reduces the potential water supply for all users. In May 2000, the
San Luis & Delta-Mendota Water Authority (SLDMWA) developed a plan to respond to
combined effects of the low-point problem and drawdown limitations. As described
in the SLDMWA plan, solutions to the low-point problem should address effective
storage in San Luis Reservoir as well as the timing and rate of water supplied from
the reservoir.
Tackling the Low-Point Problem – the San Luis Reservoir LowPoint Improvement Project
The CALFED consortium of state and federal agencies was established in May 1995 to
develop a comprehensive long-term plan for restoring the Bay–Delta environment and
improving the management of California’s water resources. In August 2000, CALFED
issued a Programmatic Record of Decision (ROD) representing the culmination of
its California Environmental Quality Act (CEQA) and National Environmental Policy
Act (NEPA) environmental compliance process. An
important outcome of the ROD was the identification
of a variety of water projects to be implemented
throughout the state.
The CALFED program consists of several components,
among them Watersheds, Water Supply Reliability,
Storage, Conveyance, and Water Quality. Under the
Conveyance component, the ROD identifies the need
for “a bypass canal to the San Felipe Unit at the San
Luis Reservoir” and recommends the allocation of
Proposition 13 funds to SCVWD to support studies
of the bypass canal in conjunction with expanded
local storage, stating that
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Local Storage
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CALFED schematic showing concept for bypass canal
serving San Felipe Division
… When operated in conjunction with local storage, this canal would allow Santa
Clara Valley Water District to receive water directly from the Delta pumping
facilities, thereby avoiding water quality problems associated with the low
point water levels in San Luis Reservoir. Resolving this low point issue also will
increase the effective storage capacity in San Luis Reservoir up to 200 TAF.
The SCVWD began the San Luis Reservoir Low-Point Improvement Project in early
2001, and is now working with the U.S. Bureau of Reclamation to conduct a feasibility analysis and formulate a solution to the low-point problem. As recommended
by the CALFED ROD, the project is funded by a Proposition 13 grant administered
by the California Department of Water Resources (DWR).
Section 1
Project Purpose
The goal of the Low-Point Improvement Project is to increase the operational flexibility of storage in San Luis Reservoir and ensure a high quality, reliable water
supply for the San Felipe Division contractors. To achieve this goal, the project
incorporates the following specific objectives.
1. Increase the operational flexibility of San Luis Reservoir by increasing the
effective storage.
Increasing operational flexibility of San Luis Reservoir by providing up to 200
TAF of additional storage capacity to the SWP and the CVP. Solving the low point
problem will increase the amount of water available for agricultural, domestic,
industrial, and environmental uses.
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2. Ensure that the San Felipe Division contractors are able to use their annual
Central Valley Project contract allocation to meet their water supply and
water quality commitments.
Because San Luis Reservoir provides about one-third of the San Felipe Division
Water agencies' annual supply, and the low-point problem has the potential to
affect about half of that allocation, this represents a significant concern. The
low-point problem occurs in the late summer and early fall when these water
supplies are needed most.
3. Provide opportunities for project-related environmental and other improvements.
Consistent with SCVWD policy, opportunities to enhance or restore natural resource
benefits of streams and watersheds will be identified. Depending on the preferred
solution to the low-point problem, various enhancements and improvements (for
example, open space, trails, and environmental restoration) could be integrated
into the project.
Project Team
SCVWD is responsible for managing the engineering and environmental studies
required for the Low-Point Improvement Project, and will serve as the lead agency
for CEQA compliance. SCVWD has retained Montgomery Watson Harza and Jones &
Stokes to provide engineering and environmental consulting services, respectively.
The U.S. Bureau of Reclamation will act as the lead agency for NEPA compliance.
Project Study Approach and Schedule
The project team (SCVWD, Montgomery Watson Harza, and Jones & Stokes) is relying
on an integrated approach that combines engineering and environmental studies
with stakeholder outreach, and incorporates stakeholder input as a key factor in
the development and evaluation of project alternatives. The following chart shows
the overall study approach and project schedule.
Section 1
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Study Approach and Schedule
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Section 1
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Section 2
The Alternatives Development
and Screening Process
Although the CALFED ROD identified a bypass canal as a potential solution to the lowpoint problem, SCVWD has taken a broader view and is considering a range of possible
solutions. This approach will offer a better opportunity to develop the optimal solution, and is more consistent with CEQA and NEPA regulatory guidance requiring project
proponents to consider a reasonable range of alternatives. This section summarizes
the process through which possible solutions were developed and screened for the
Low-Point Improvement Project.
Alternatives Development
Several sources provided key input in the development of possible solutions, or project
alternatives, including
• the project team,
• the public,
• project stakeholders,
• regulatory agency staff, and
• other previous and ongoing studies.
Previous and ongoing studies provided essential background information, which was
used to the greatest extent possible, in order to ensure consistency with other efforts
and to control project costs by avoiding duplication of effort.
Public Input
As required by CEQA and NEPA, SCVWD and USBR held public scoping meetings for the
Low-Point Improvement Project in August 2002. The first
scoping meeting for the Low-Point ImThe Scoping Process
Scoping refers to the public outreach process provement Project was held on August
conducted under CEQA and NEPA to deter- 26 at the SCVWD headquarters in San
mine the coverage and content of an envi- Jose, and the second meeting was held
ronmental impact report or environmental on August 27 at the Romero Visitors’
impact statement. Scoping contributes to Center facility at San Luis Reservoir.
the selection of a range of project alterna- Numerous comments were received
tives to be considered, and can also help in person at the scoping meetings;
to establish methods of analysis, identify in writing on questionnaire forms
the environmental effects that will be con- distributed at the meetings; and via
sidered in detail, and develop mitigation
letters, faxes, and emails received
measures to avoid or compensate for adverse
after the meetings. Comments
effects.
came from private individuals and
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Section 2
from agency representatives, and included suggestions for alternatives
that should be considered as well as comments regarding issues of concern. A separate Scoping Summary Report was prepared in October 2002
to thoroughly document the results of these meetings. It can be viewed
online at the SCVWD website (http://www.valleywater.org).
Stakeholder and Regulatory Agency Input
In addition to the scoping meetings, SCVWD has conducted more than 25
briefings to date for agencies, environmental organizations, and other
special interest groups. A complete description of the stakeholder and
agency outreach program is provided in Section 3 of this report. An
important result of the outreach program for alternatives development
has been ongoing dialogue regarding potential alternative solutions.
As discussed below, stakeholder and agency input was also essential
to the development and weighting of screening criteria.
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Ongoing Studies
A number of other projects and studies now in progress provided valuable information used in alternatives development for the Low-Point Improvement Project.
SCVWD activities that were key in this regard include the Integrated Water Resources
Plan Update, the Treated Water Improvement Program, the District-Wide Habitat
Conservation Plan, and ongoing development of the SCVWD’s geographic information system and related mapping projects. In addition, the SBCWD and PVWMA
are presently implementing basin management plans for their service areas, and
the U.S. Bureau of Reclamation is completing an integrated resource plan for the
Westside Region of the San Joaquin Valley on behalf of the CVP. The Westside
Integrated Resource Plan focuses on alternative means of reducing imbalances
between water demand and water supply, groundwater, land use, drainage, and
water quality. Since San Luis Reservoir is a principal source of water supply to the
Westside Region, solving the low-point problem would represent a major benefit
to water users in this area.
To provide a consistent set of planning criteria for the various CALFED projects,
CALFED has initiated a Common Assumptions Workgroup. The Low-Point Improvement Project team has actively participated in this workgroup and will continue
to do so as the project proceeds.
Solution Concept Categories
Based on input from the sources discussed above, seven broad categories of solution concepts were identified.
Section 2
• No Project/No Action – The No Project/No Action Alternative means that no
project would be implemented and no actions would be taken to resolve the
low-point problem. Both CEQA and NEPA require detailed analysis of the No
Project/No Action Alternative to ensure that the outcome of taking no action is
thoroughly understood.
• Institutional Agreements – This category of concepts includes nonstructural
institutional agreements such as contract modifications, rescheduling of water
deliveries, water exchanges, water banking, and modification of operating agreements and procedures. Under such alternatives, no new infrastructure would be
constructed, but existing infrastructure could be operated differently.
• Source Water Quality Control – This category of concepts would involve controlling
water quality onsite, in San Luis Reservoir. The range of potential solutions was
derived from reservoir management and algae-control methods that have been
used successfully in other water bodies to address issues similar to the San Luis
Reservoir algae problem.
• Water Treatment – This category of concepts would involve implementing additional water treatment processes offsite, at existing or new water treatment
plants. The range of potential solutions was based on techniques that have been
used successfully at other facilities to remove algae that clog filters, reduce
treatment plant production, and cause taste and odor issues.
• Conveyance Facilities – This category of concepts would develop new infrastructure to allow diversion of water around or beneath San Luis Reservoir during the
low-point period. A new conveyance system would allow San Felipe Division
deliveries to bypass the quality-impaired storage pool in the reservoir, and would
prevent supply interruption related to the reservoir water level dropping below
the lower Pacheco intake.
• Local Reservoir Storage – This category of concepts would expand existing reservoir storage or construct new storage to allow water to be pumped and stored
offsite during the wet season for release during the dry season when the lowpoint problem occurs.
• Alternate Water Supplies – This category of concepts would entail reoperation
(modified operation) of existing water supplies and/or use of new water supplies.
Alternate water supplies would be used to replace San Luis Reservoir water during
interruptions resulting from low-point conditions.
A fundamental precedent to the development of any alternative is the implementation of SCVWD’s existing and planned water conservation and wastewater
reclamation and reuse programs.
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Section 2
The Screening Process
What is Alternatives Screening?
Both CEQA and NEPA require that an environmental impact report/environmental
impact statement analyze a reasonable range of feasible project alternatives.
Alternatives screening refers to the process of evaluating a broad range of conceptual alternatives to identify those that should be carried forward for detailed
analysis in the project environmental impact report/environmental impact statement. The purpose of the screening process is to systematically narrow the range
of possible alternatives to focus increasingly detailed evaluations on the more
feasible and promising alternatives.
Alternatives screening is a key phase in project development, because it helps project
sponsors to identify and focus on the most workable solutions to a problem. It is
also an essential part of the environmental review process, helping to ensure that
the public has the opportunity to review and comment on all solutions analyzed
during development of a draft environmental impact report/environmental impact
statement.
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Alternatives Screening for the Low-Point Improvement Project
As described in Section 1, the District has adopted an integrated approach to
the Low-Point Improvement Project, incorporating a combination of engineering analysis, environmental review, and stakeholder outreach. This approach was
carried through in the alternatives screening process, which entailed two basic
steps—Level 1 screening and Level 2 screening—and was designed to involve
continuous feedback allowing reformulation and modification of alternatives. New
alternatives introduced at any point in the process were considered in accordance
with the steps shown in the diagram below.
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Section 2
An essential component of any screening process is the development of evaluation
criteria that allow the project team to identify the more feasible and promising
alternatives at each stage of the process. Evaluation criteria for the Low-Point
Improvement Project were developed on the basis of project objectives (i.e., the
degree to which a potential solution would satisfy the stated project objectives) and
feasibility incorporating stakeholder input. Additional information on the development and refinement of screening criteria is provided in the following paragraphs
describing the Level 1 and Level 2 screening procedures.
Problem
Definition
Drawdown Limitations
for San Luis Reservoir
Potential Interruption
in Water Supply
Algae Growth in
San Luis Reservoir
CALFED Environmental
Objectives
SCVWD Mission and
Policies
Project Goal
and Purposes
Level 1
Screening
San Luis Reservoir
Operational
Flexibility
San Luis Reservoir
Operational
Flexibility
Level of San Luis
Reservoir Operational
Flexibility
San Felipe Division
Water Supply
Reliability
San Felipe Division's
Ability to Utilize
CVP Allocation
San Felipe Division
Water Quality
San Felipe Division
Water Quality
San Felipe Division
Water Supply and
Water Quality
Opportunities for
Environmental and
Other Improvements
Level 2
Screening
Feasibility (Level 3)
Screening and
EIR/EIS Analysis
Identification
of Preferred
Alternative
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Regional
Considerations
Additional Screening
Criteria and/or
Subcriteria
Effects on Sensitive
Resources
Assessment
of Potential
Environment
Impacts
Other Environmental
Effects
Economics
Technical
Feasibility
Project Risks
Level 1 Screening
The purpose of Level 1 screening was to eliminate solution concepts that failed to
meet project objectives or fundamental tests of technical feasibility. Evaluations
at this early level of project development were based on readily available data,
including information from previous studies; experience from similar projects; and
professional judgment.
At the initial level of screening, the process must provide some focus, but should
not be so restrictive that it eliminates potentially viable solutions. Therefore, the
number of criteria used in Level 1 was relatively limited, and individual criteria were
broad. In addition, at Level 1, each concept was rated relative to the screening
criteria rather than being compared and ranked relative to the other concepts. Level
1 screening also emphasized the identification of concepts that were individually
unsuccessful but could be reformulated or combined with other concepts to meet
the screening criteria.
Section 2
Level 1 Screening used a simple matrix to track the evaluation of the solution concepts. This approach is widely used in engineering project development because
it is convenient, systematic, and visually accessible. The Level 1 screening matrix
is included as Exhibit I at the back of this report.
Following are the evaluation criteria used in Level 1 screening.
• San Luis Reservoir Flexibility: Does the concept have the potential to increase
the operational flexibility of San Luis Reservoir? If San Luis Reservoir could
regularly be drawn down below the San Felipe Division low point, this would
increase the operational storage available to the SWP and the CVP by up to 200
TAF. In addition, this additional draw down could be timed to provide more
flexibility in meeting the annual water demand patterns of the SWP and the CVP.
This criterion is an evaluation of the concept's ability to provide this operational
flexibility in San Luis Reservoir.
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• San Felipe Division Water Supply Reliability: Is the concept capable of providing a quantity of water supply equivalent to the scheduled deliveries from San
Luis Reservoir to the San Felipe Division? Based upon historical and projected
operational data, the low point months typically occur from July through October.
Water demands for the San Felipe Division are estimated to be 100 TAF during
this four-month period. If the water supply from San Luis Reservoir were not
available to the San Felipe Division during the low-point months, there would be
significant public health, safety, and economic impacts to the San Felipe Division contractors. This criterion evaluates the ability of the concept to provide
a sufficient quantity of water supply to the San Felipe Division during the low
point months.
• San Felipe Division Water Quality: Is the concept capable of sufficiently reducing algae concentrations to avoid impacts on municipal water treatment plants,
agricultural drip irrigation systems, and groundwater recharge facilities for the
San Felipe Division? If algae in the water supply from San Luis Reservoir can
be controlled, removed, or avoided, then impacts to municipal, industrial, and
agricultural water supplies will be minimized or will not occur. This criterion
evaluates the ability of the concept to avoid the impacts of algae in the water
supply provided to the San Felipe Division contractors from San Luis Reservoir.
• Technical Feasibility: Is the concept technically feasible? The definition of
technical feasibility used for all concept categories included the need to maintain
the original design capacity (490 cfs) of the San Felipe Division facilities; that
is, if a concept would reduce the existing capacity of the San Felipe Division’s
Section 2
facilities to convey water, the concept was judged to be technically infeasible.
For some concept categories, more detailed definitions of technical feasibility
were developed to ensure a thorough evaluation of potential solutions. The
sidebar on this page provides an example.
All concepts that passed the Level 1 screening
evaluation were carried forward for a second, more
intensive round of screening. The purpose of Level
2 screening is to further limit the number of alternatives to a reasonable range to be carried forward
to the environmental review process. Prior to Level
2 screening, the alternatives that passed Level 1
screening were developed in more detail to provide
additional information regarding engineering and
economic feasibility and potential environmental
impacts.
• weighting of evaluation criteria,
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• ability to systematically compare different types
of alternatives against one another,
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• improved identification of gaps in existing data,
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Level 2 screening employed a computer-supported
decision making tool called Criterium Decision PlusTM
(CDP) . Computer-based “decision models” simply
analyze the data more quickly than manual methods
and present the results graphically for easier interpretation. The computer-based tool also provides
additional benefits, such as:
For concepts in the Local Reservoir Storage category, the
definition of technical feasibility was amplified to include
benchmark criteria for reservoir capacity; elevation, which
determines the extent to which pumping would be required,
and thus affects the cost and difficulty of delivering water
to the San Felipe Division contractors; distance to existing
infrastructure, which also relates to the difficulty and cost of
delivering water to San Felipe Division contractors; and the
relative efficiency of dam volume to storage capacity, which
is an indicator of the cost-effectiveness of developing or
expanding a dam site. In addition, reservoir sites upstream
of the Hollister Conduit Bifurcation on the Pacheco Conduit
were preferred, to maintain the existing operational procedures for serving all of the San Felipe Division contractors.
Depending on their locations, reservoir sites downstream
of the Hollister Conduit Bifurcation might be technically
feasible, but would require backfeeding through the Santa
Clara Conduit, and the need to backfeed would significantly
increase operational complexity. Finally, local storage could
theoretically be provided at a combination of sites. However,
because of the cost and difficulty of developing new or expanded storage,
only those sites
that would
accommodate the required storage volume
at a single
location were
considered feasible at this level of
project development.
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Level 2 Screening
Case Study – Expanding the Definition of
Technical Feasibility for Reservoir Storage
Concepts
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Level 1 screening did not include environmental criteria, because at this stage the solution concepts
were very broadly defined, and the information
available on project construction footprints and operational constraints (key factors in the evaluation
of environmental impacts under CEQA and NEPA) was
inadequate for substantive analysis. This was not
intended to limit the importance of the environmental perspective; rather, screening that depended on
environmental criteria was deferred to Level 2, when
more information would be available.
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Bifurcation
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Section 2
• ability to complete sensitivity analyses, and
• step-by-step documentation of the evaluation process.
CDP was selected as the preferred modeling tool for Level 2 screening based on
evaluation of a range of similar tools currently available on the market.
The evaluation criteria used in Level 2 screening were more detailed and more
specific than those applied in the matrix evaluation for Level 1 screening. They
were developed by SCVWD staff and the consultant team with input from project
stakeholders and regulatory agency staff (see Section 3 of this report). Development
of Level 2 screening criteria began with the collection of an initial list of criteria
and assessments of their relative importance (“weighting”) from each participating
group. Following CDP analyses and discussions with stakeholders and regulatory
agency representatives, the initial list of criteria and the initial weightings were
refined as follows.
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• Selection of Weights – The purpose of obtaining weights from different groups
was to identify trends and obtain general agreement. While there was some
variation among the groups, the pattern of the relative weights was similar for
all groups. The consensus that emerged from discussion among the contributing
groups was that the “final” weights used in CDP analysis for Level 2 screening
should reflect the weighted average of the values provided by SCVWD staff, the
members of the project Stakeholder Committee, and the project Regulatory
Compliance Work Group (see Section 3).
Level of Importance (Weight) on a Scale of 1 to 10
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Section 2
• Increased Emphasis on Environmental Issues – The original list of criteria included all potential environmental issues under a single criterion. Stakeholders
and regulatory agencies felt that this approach placed insufficient emphasis on
environmental issues. Therefore, the single environmental criterion was divided
into two criteria and relative weights were adjusted accordingly. The result of this
refinement was to increase the relative weight of environmental considerations
from 14% to 25% of each alternative’s total Level 2 score.
The evaluation criteria used in the CDP model for Level 2 screening are presented
in the table below, along with their relative weights.
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Level 2 Screening Criteria
Unlike Level 1 screening, Level 2 screening compared each alternative against the
others and ranked the alternatives’ performance relative to each screening criterion.
In order to accomplish this systematically, the CDP model requires that a metric,
or specific measurable attribute, be identified for each criterion. For example,
the metric used for the Economics criterion combined the present value of the
capital costs that would be required with anticipated operation and maintenance
costs. Level 2 ranking helped focus results on those alternatives that did not rate
well compared to the other alternatives. Additional evaluation of those alternatives helped to identify specific factors that caused the alternative to rate low
and indicate that it is not reasonable to carry that alternative forward for further
consideration.
17
Section 2
Holladay Aqueduct
18
An example of the integrated planning approach
used for the Low-Point Improvement Project is
the Holladay Aqueduct concept. Mr. Ken Holladay of Gilroy contacted the SCVWD to suggest
this concept after hearing about the studies
in progress for the project. The idea was developed in the 1950s by his father, Mr. Cedric
(Ted) Holladay, a former Santa Clara County
game warden for the California Department of
Fish and Game. The Holladay Aqueduct would
involve a bypass pipeline beginning near the
City of Patterson and extending westward up
the flank of the Diablo Range to a terminus
at the crest of the range. From the crest, the
water would flow down natural stream channels
through open space, including Henry Coe State
Park, into Coyote and Anderson Reservoirs. The
concept was originally proposed by the elder Mr.
Holladay as an alternative to San Luis Reservoir
and the San Felipe Division infrastructure as a
method of delivering imported water to Santa
Clara County. Following the contact by Mr. Ken
Holladay, the concept was incorporated into the
alternatives development and screening process
for the Low-Point Improvement Project. The
Holladay Aqueduct was considered as an option
for the northerly bypass corridor discussed in
Section 4, but was eliminated because its length
and the elevation lift required to convey water
to the crest of the Diablo Range would require
substantial and costly pumping operations.
It should be emphasized that the CDP model served as a tool
to assist in organizing and evaluating screening data. The final
Level 2 screening decisions were derived in part from the results
of CDP modeling, but also incorporated further input from project
stakeholders and supplemental technical evaluations. In addition,
a series of sensitivity analyses were performed to backcheck and
validate results. Sensitivity analyses used the CDP model to view
each criterion independently and compare the alternatives based
only on that single criterion. This tested the model for undue
sensitivity to each criterion, and helped to ensure that the results
were consistent and reasonable.
Section 3
Outreach Activities
Stakeholders have been an integral part of
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the process almost since the inception of
the Low-Point Improvement Project. Public
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scoping meetings held for the project, and
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the importance of public input in the alterna��
tives development and screening process, are
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described in Section 2 of this report. SCVWD
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felt that intermittent briefings would not be
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sufficient to sustain the open and ongoing
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communication between project stakeholders
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and the project team that would be essential
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to the success of the project. Consequently,
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they invited individuals representing a wide
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range of stakeholder and regulatory agency
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perspectives to participate in a regularly
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convened Stakeholder Committee and Regula��
tory Compliance Work Group for the Low-Point
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Improvement Project. In addition, to date
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SCVWD has conducted numerous agency and
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interest group briefings to explain the low��
point problem, describe potential solutions
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identified to date, and share information on
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the alternatives screening process.
Stakeholder
Committee
The Stakeholder Committee represents a
wide variety of perspectives and interests, including local
and statewide water
Views from the August 2002 scoping meetings
agencies as well as local business, agricultural, and environmental organizations. SCVWD’s goal in forming
the Stakeholder Committee was to facilitate early and ongoing communication with
various stakeholders and interest groups in order to develop a preferred alternative
that not only meets the project objectives but also reflects community interests and
is acceptable to the public.
19
Section 3
The role of the Stakeholder Committee is to provide input and feedback to SCVWD
and the project team throughout the project planning process, and to identify issues and concerns related to various project activities, including
• screening of solution concepts (Level 1 alternatives screening),
• development and screening of conceptual alternatives (Level 2 alternatives
screening), and
• identification of the preferred alternative.
The Stakeholder Committee participates in workshops and in regular monthly or
quarterly meetings. Meeting topics are identified based on project progress. Organizations currently represented on the Stakeholder Committee include
• California Department of Parks and Recreation,
20
• California Department of Water Resources,
• CALFED Bay-Delta Program,
• CVP Water Association,
• Environmental Defense,
• Pacheco Pass Water District,
• PVWMA,
• San Jose Silicon Valley Chamber of Commerce,
• San Luis and Delta-Mendota Water Authority,
• Santa Clara County Farm Bureau,
• Santa Clara Valley Audubon Society,
• SBCWD,
• SCVWD Agricultural Water Advisory Committee,
• SCVWD Water Retailers Committee,
• Silicon Valley Manufacturing Group,
• State Water Contractors,
• Streams for Tomorrow, and
• U.S. Bureau of Reclamation.
Additional members will be added to the Stakeholder Committee as the project
continues to develop.
Section 3
Regulatory Compliance Work Group
The District formed the Regulatory Compliance Work Group because of the project’s
complexity and large scale and the resulting need to facilitate early consultation and
effective coordination with agencies that have resource management and regulatory responsibilities in the project area. The Regulatory Compliance Work Group’s
role is to provide the resource and regulatory agency perspective in a variety of
essential project tasks, including
• developing an appropriate approach to meet permitting and environmental
compliance requirements for the project,
• identifying the range of alternatives to be analyzed and the range of resource
issues to be addressed in the project environmental impact report/environmental
impact statement,
• selecting methods for the analysis of project environmental impacts, and
• developing mitigation measures to avoid or compensate for significant environmental impacts.
Going forward, the Regulatory Compliance Work Group is also tasked with working
in consultation with CALFED’s Science Program to develop adaptive management
strategies that will address any uncertainties regarding the project’s effectiveness,
the nature or severity of project impacts, and/or the success of the mitigation
measures implemented to avoid or compensate for those impacts.
Like the Stakeholder Committee, the Regulatory Compliance Work Group participates
in meetings addressing topics related to project progress. Organizations that are
represented on the RCWG include
• California Department of Fish and Game,
• California Department of Water Resources,
• NOAA Fisheries (National Marine Fisheries Service),
• San Francisco Bay Regional Water Quality Control Board,
• State Water Resources Control Board,
• U.S. Army Corps of Engineers,
• U.S. Environmental Protection Agency, Region 9,
• U.S. Fish and Wildlife Service, and
• U.S. Bureau of Reclamation.
21
Section 3
22
Section 4
Results of Alternatives Screening
This section summarizes the results of the screening process described in Section 2. It
identifies the alternatives that passed the Level 1 and 2 screening tests, but focuses
on those that were eliminated from further consideration at each level in order to
describe the reasons why they were eliminated. The alternatives that passed Level 2
screening (the feasible alternatives) are described in detail in Section 5.
Results of Level 1 Screening
In the Level 1 screening process, approximately 75 solution concepts were evaluated
relative to several criteria that addressed their ability to meet project objectives and
their technical feasibility. Screening results and rationale were tracked on a matrix,
which is presented in full in the Appendix on file at SCVWD headquarters.
23
The following concepts passed all of the Level 1 screening criteria.
1. Bypass conveyance facilities along a northern route (“northerly
bypass corridor”).
2. Bypass conveyance facilities along a southern route (“southerly
bypass corridor”).
3. Expanded storage capacity at Anderson Reservoir.
4. New dam and reservoir at Los Osos site.
5. New dam and expanded storage capacity at Pacheco Reservoir.
6. Desalination facilities at San Francisco Bay.
7. Desalination facilities at Monterey Bay.
8. Desalination facilities at San Francisco Bay, Monterey Bay, and the
San Benito groundwater basin.
Seven additional solution concepts failed some of the Level 1 criteria
individually, but were identified as providing some benefit if combined
with other concepts.
A number of the solution concepts
included in the alternatives screening process were suggested by project stakeholders. Examples include
using floating covers or nontoxic
shading agents (dyes) to prevent
algal growth in the reservoir; extending and lowering the Pacheco
intake to access deeper reservoir
waters offering better water quality; implementing desalination
to provide an alternate source of
water supply; and constructing the
Holladay Aqueduct described on
page 18.
1. Algae harvesting.
2. Algicide application.
3. Managed stratification (modifying inlet structures to allow withdrawal of water from
the reservoir’s upper layer in addition to the presently available withdrawals from
the reservoir’s deep waters).
4. Dissolved air flotation (DAF) treatment to remove algae at Pacheco intake facility.
Section 4
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Section 4
5. DAF treatment at existing Coyote Pump Station and new facilities serving SBCWD
and PVWMA.
6. DAF treatment at existing Santa Teresa and Rinconada Water Treatment Plants
and new facilities serving SBCWD and PVWMA.
7. Other regional projects, such as expansion of storage at Los Vaqueros Reservoir,
expansion of storage at Calaveras Reservoir, and/or options from the SBCWD and
PVWMA basin management plans.
In addition, as required by both CEQA and NEPA, the No Project/No Action Alternative was carried forward for further study. Thus, a total of 16 conceptual alternatives
remained in consideration after the Level 1 screening process was completed: the
eight that passed by themselves, the seven combination alternatives, and the No
Project/No Action Alternative. Exhibit II at the end of this report is a map showing
the locations of major facilities required for the conceptual alternatives.
25
Level 2 Screening Results
Before Level 2 screening could begin, the 16 alternatives identified through Level
1 screening as potentially offering feasible solutions to the project objectives were
developed in more detail to provide additional information on their engineering
and economic feasibility and their possible environmental impacts. The 16 alternatives then underwent a preliminary evaluation using the CDP model, as described
in Section 2 (see the table below for the scores from this round of screening). The
source water quality control and treatment alternatives were combined with other
regional projects to meet all project objectives and provide a consistent basis for
comparison using the CDP model.
Type
Alternative
Score
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Section 4
The project team, the Stakeholder Committee, and the Regulatory Compliance Work
Group reviewed and discussed these preliminary results. Based on these discussions,
additional information was collected for some alternatives, and the model was recalibrated for an additional screening run (see Section 2). Evaluations conducted at
this stage of the process also provided information that allowed the project team
to explore reformulating and recombining alternatives for greater success. The
outcome of the Level 2 screening process was the identification of an initial list of
six feasible project alternatives, which was then presented to project stakeholders
during a series of briefings. Following are the feasible alternatives that were carried forward to the stakeholder outreach program for discussion.
• No Project/No Action Alternative.
• Algae management (algae harvesting, algicide application).
• DAF treatment.
26
• Southerly bypass corridor.
• Expanded storage at Pacheco Reservoir.
• Other regional projects (e.g., expansion of storage at Los Vaqueros Reservoir,
expansion of storage at Calaveras Reservoir, and/or options from the SBCWD and
PVWMA basin management plans).
The feasible alternatives are described in more detail in Section 5 of this report. The
following paragraphs describe the alternatives eliminated from further consideration
at this point, and the reasons they were judged unlikely to be successful.
Which Alternatives Were Eliminated In Level 2, and Why?
The following alternatives were eliminated from further consideration as a result
of Level 2 screening evaluations.
• Managed stratification.
• Northerly bypass corridor.
• Expansion of Anderson Reservoir.
• New dam and reservoir at Los Osos site.
• Large-scale desalination facilities at all locations studied (San Francisco Bay,
Monterey Bay, and San Benito groundwater basin).
The table on the following pages summarizes the specific reasons these alternatives
were eliminated from further consideration.
• In addition, in order to avoid taking the reservoir out of service
during construction, modifications to the Gianelli Inlet/Outlet
Works would likely need to be completed under as much as 200
feet of water, presenting substantial logistical and cost
challenges.
• Modifying the Gianelli Inlet/Outlet Works to include inlets at a
variety of depths would allow reservoir operators to selectively
withdraw water from the upper layer of water in the reservoir
(the epilimnion) in addition to the presently available
withdrawals from the reservoir's lower layer (hypolimnion),
theoretically offering additional operational flexibility.
However, while this technique is effective in some reservoirs, it
was evaluated as unlikely to succeed in San Luis Reservoir;
instead of resolving water quality problems, managed
stratification would likely result in algae being drawn into the
upper intake at the modified Gianelli Inlet/Outlet Works,
potentially degrading water deliveries to other south of Delta
CVP and SWP contractors in the same way that deliveries to the
San Felipe Division are now affected. The quality of water
delivered to the San Felipe Division could improve, but water
quality problems related to algal content would almost certainly
be transferred downstream to other south of Delta users.
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• This alternative would involve pumping water over mountainous
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terrain in portions of the Diablo Range. Depending on the route
selected, three or more major pump stations and a long pipeline
would be required. This would increase construction cost and
project footprint, and because of the expanded footprint, could
result in increased environmental impacts by comparison with
the southerly bypass corridor.
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Managed stratification is the most
costly of the source water quality
control options, at approximately
twice the cost of algae harvesting or
algicide application.
Degradation of water deliveries to
downstream CVP and SWP users would
represent a serious concern because of
potential adverse impacts on
municipal water treatment plants and
agricultural uses.
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This alternative is substantially more
costly than the others advanced to
Level 2 screening, but would not offer
any additional benefits.
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Section 4
27
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• An expanded Anderson Reservoir would inundate a known
hazardous waste site in the northern portion of the watershed.
• There are several geologic issues related to constructing a larger
dam and reservoir at this site, including its location in close
proximity to the active Calaveras fault and over the trace of the
potentially active Silver Creek fault. In addition, the left
(southeast) abutment of a larger dam would encroach on a
major active landslide, while a larger reservoir would inundate
and/or add significant loading to several major existing
landslides on both the east and west sides of the reservoir.
• The existing dam was not designed for expansion; expansion of
reservoir storage would effectively require demolition of the
existing dam and construction of a new dam on the site.
• With a length of at least 19 miles, the northerly bypass corridor
is substantially longer than the 7-mile-long southerly bypass
corridor. Additional pipeline length translates into increased
construction cost and additional environmental impacts.
• Operation of three or more in-sequence pump stations would be
complex and would reduce the overall reliability of the delivery
system for the San Felipe Division.
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• Because of the need for multiple pumping operations, this
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alternative would be very energy-intensive.
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• The existing Anderson Reservoir is
classified as an emergency water
supply for SCVWD's surface water
treatment plants. At present,
extensive recreation is allowed on the
reservoir. However, an expanded
reservoir would be used as a primary
supply to surface water treatment
plants. Thus, if the reservoir were
expanded, recreational activities
would have to be significantly
reduced.
• An expanded reservoir would inundate
some 100 homes and other structures.
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28
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This alternative is substantially more
costly than the others advanced to
Level 2 screening, but would not offer
any additional benefits.
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Section 4
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29
Section 4
30
Section 5
Feasible Alternatives Recommended
for Further Consideration
This section presents the feasible alternatives identified through the screening process described in Section 2 and recommended for detailed evaluation in the project
environmental impact report/environmental impact statement.
Refinement of Feasible Alternatives
Following the completion of Level 2 screening, feedback from stakeholder briefings led
to further refinement of the slate of feasible alternatives identified in Level 2. Specifically, as it was originally identified in Level 2 screening, the southerly bypass corridor
alternative incorporated multiple options for new conveyance facilities. In response
to stakeholder input, which consistently identified the need to study the effects of a
lowered intake, the original southerly bypass alternative has been separated into two
alternatives to facilitate a thorough analysis. The two alternatives are now referred to
as Lower San Felipe Intake and Bypass San Luis Reservoir. The primary distinction
between them is the source of the water supply: the Lower San Felipe Intake Alternative would draw water from lower elevations in San Luis Reservoir, while the Bypass
San Luis Reservoir Alternative would divert water from the Delta-Mendota Canal.
The terminology for describing the feasible alternatives has also been refined in response to stakeholder input, in order to describe the alternatives more clearly. The
table below compares the original Level 2 terminology with the revised terminology
proposed for use going forward.
Former (Level 2) Name
Revised Name
Algae management
(algae harvesting, algicide application)
Algae management
Dissolved air flotation treatment
Dissolved air flotation treatment
Southerly bypass corridor
Lower San Felipe intake
Bypass San Luis Reservoir
Expanded storage at Pacheco Reservoir
Expand Pacheco Reservoir
Other regional projects
Combination solution
No project/no action
No project/no action
Note that both algae management and dissolved air flotation treatment represent partial solutions.
These two alternatives address the water quality aspects of the low-point problem but would need to be
combined with other alternatives to meet all of the project objectives.
31
Section 5
The chart below shows the relative timing and complexity of implementing the six
feasible alternatives. The following paragraphs briefly describe each feasible alternative, including the rationale for carrying it forward for further consideration.
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Algae Management
Algae management would involve controlling algae growth in San Luis Reservoir
via algicide application and/or algae harvesting. This alternative would address
only the water quality facet of the low-point problem, and would need to be
combined with other alternatives to meet all project objectives.
Following are the key rationales for further consideration of algae management
as a feasible alternative.
• Depending on its effectiveness, algae management has the potential to
reduce the capacity required from other alternatives in a combination solution,
because it would improve water quality in San Luis Reservoir and increase the
usability of the San Luis Reservoir resource. This in turn would reduce the
required operating timeframe and the cost of other alternatives included in a
combination solution.
• Algae management would entail a very low initial capital cost (approximately
$1 million) and could be implemented relatively quickly. Combining algae management with another alternative to meet all project objectives would have an
estimated present value of $161 to $182 million.
Section 5
Dissolved Air Flotation Treatment
DAF treatment would utilize a proven water treatment process to remove algae at
existing or new water treatment plants. The treatment facilities could be
installed at a single centralized location near the existing Pacheco Pumping
Plant, or could be decentralized at a combination of existing and new water
treatment plants. This alternative would address only the water quality
facet of the low-point problem, and would need to be combined with other
alternatives to meet all project objectives.
Following are the key rationales for further consideration of DAF treatment
as a feasible alternative.
• Depending on its effectiveness, DAF treatment has the potential to reduce the
capacity required from other alternatives in a combination solution, because
it would increase the usability of the San Luis Reservoir resource. This in turn
would reduce the required operating timeframe and the cost of other alternatives
included in a combination solution.
• DAF treatment would entail a relatively low initial capital cost (approximately
$147 to $169 million) and could be implemented relatively quickly compared to
other feasible alternatives. Combining DAF treatment with another alternative
would have an estimated present value of $272 to $299 million.
Lower San Felipe Intake
Lowering the San Felipe intake would draw water from lower elevations of San Luis
Reservoir, allowing the San Felipe Division to use supply from elevations comparable
to those presently accessed by the SWP and other south of Delta CVP contractors,
and largely avoiding the impacts of algal growth in the reservoir. Additional
studies are required to thoroughly evaluate lowering the existing intake to
the Pacheco Pumping Plant. If this alternative were selected, institutional,
operational, or other measures would be required to ensure that the water
supply reliability needs of the San Felipe Division were met.
Following are the key rationales for further consideration of lowering the
San Felipe intake as a feasible alternative.
• Lowering the San Felipe intake would allow San Felipe contractors to use highquality water from lower elevations in San Luis Reservoir, possibly ensuring better
water quality than from the Bypass San Luis Reservoir alternative.
• The estimated cost of this alternative will depend upon the results of more detailed feasibility studies and the potential methods of construction. However,
preliminary estimates indicate that this alternative would have a present value
cost of approximately $238 million.
33
Section 5
• Since this alternative would be constructed underwater within San Luis Reservoir,
environmental impacts would be expected to be minimal compared to other
feasible alternatives.
Construction of new conveyance facilities in the southerly bypass corridor would
allow water to be diverted around San Luis Reservoir for delivery to the San
Felipe Division during the low-point months. A number of potential diversion
locations have been identified, but the most likely site for a new intake and
pump station would be on the Delta-Mendota Canal near its turnout toward
O’Neill Forebay. The conveyance facilities would extend from the new intake
to the existing Pacheco Regulating Tank; they could be located within or
adjacent to the reservoir, and, depending on their location, could consist of
a pipeline, a tunnel, or a combination of pipeline and tunnel segments.
34
Following are the key rationales for further consideration of bypassing San Luis
Reservoir, the original CALFED option, as a feasible alternative.
• The elevation lift and transport distance needed to deliver water via new conveyance in the southerly bypass corridor would be substantially less than that
required to deliver water via conveyance alternatives in the northerly bypass
corridor. Consequently, less pumping would be required, and energy consumption
and some types of environmental impacts would likely be less by comparison.
• With an estimated present value of approximately $430 million, construction of
facilities to bypass San Luis Reservoir would be less costly than other feasible
alternatives providing similar benefits.
Expand Pacheco Reservoir
Expanding Pacheco Reservoir would allow water to be pumped and stored
offsite during the wet season for release to the San Felipe Division during
the low-point months. An existing dam and 6 TAF reservoir are located at
the Pacheco Creek site, and SCVWD’s 1993 Wahler Report identified several
additional dam sites upstream. A new pipeline and pump station would
be required to convey Pacheco Reservoir water to and from the Pacheco
Conduit. A small hydropower facility could also be included in the project
if determined to be cost-effective.
Following are the key rationales for further consideration of expanding Pacheco
Reservoir as a feasible alternative.
• The site is located upstream of the existing turnout for SBCWD and the future
turnout for the PVWMA. Therefore, there would be no significant increase in the
operational complexity of the San Felipe Division transmission system if this
alternative were selected.
Section 5
• The Pacheco Reservoir is very close to the existing Pacheco Conduit (0.4 to 1.7 miles depending on the preferred dam site) and the water surface of an expanded
reservoir would be at approximately elevation 680, which
is compatible with the elevation of the Pacheco Regulating Tank located at elevation 635. A low to moderate
lift pump station would also be needed.
• The site is located approximately 11 miles east of the
Calaveras fault; preliminary evaluations suggest that
geotechnical issues related to active seismicity would
be substantially less under this alternative than under
others located closer to this active fault.
• Expanding Pacheco Reservoir could provide substantial
benefits in the form of permanent open space in the area
and enhanced streamflow for improved fish habitat in
Pacheco Creek.
• The estimated present value cost of expanding Pacheco
Reservoir is approximately $560 million. Although this
is the highest cost of the feasible alternatives, it is also
projected to provide the highest value of benefits.
No Inundation of Coe Park
As the potential solutions were identified for the
project, many stakeholders expressed their preferences or opposition to various alternatives. Most
notably, a number of groups and individuals have
expressed their objection to any alternative that
would adversely impact Henry W. Coe State Park.
As it had been described previously, the Pacheco
Reservoir expansion alternative could have inundated
approximately 30 acres of the 87,000 acre park.
Following a review of the California Public Resources
Code and consistent with SCVWD policies, the CEO
of SCVWD determined the following:
• In seeking a solution to the San Luis Reservior
low-point problem, the SCVWD will not adversely
impact Henry W. Coe State Park. There will be no
inundation of any Coe Park Lands.
• While a change in designation from State Park to
State Recreation Area might allow for a storage
facility, this change in use and purpose of Henry
W. Coe State Park would be incompatible with
SCVWD interests and the SCVWD will not seek such
a change in designated use.
Combination Solution
A combination solution could be formulated by combining feasible alternatives,
institutional agreements, reoperation of existing facilities, and other regional and
local projects. The intent of a combination solution would be to address the lowpoint problem by integrating several smaller scale projects or actions. Other regional
projects that could form part of such a solution would include the Los Vaqueros
Reservoir expansion and options from the SBCWD and PVWMA basin management
plans.
Following are the key rationales for further consideration of a combination of other
regional projects as a feasible alternative.
• A combined solution relying on coordination of other projects or components
would provide substantial flexibility in terms of potential supply capacity, implementation staging, and ability to accommodate new regional projects as they
are developed.
• Stakeholders have expressed a very high level of interest in this type of incremental alternative that does not rely on the construction of a single large capital
project.
35
Section 5
No Project/No Action
If the No Project/No Action Alternative were selected, no project would be implemented and no actions would be taken to resolve the low-point problem. This
alternative will be carried forward for detailed consideration in order to comply
with the requirements of CEQA and NEPA.
How Will The Alternatives Evolve?
The feasible alternatives recommended for further consideration represent a wide
range of solutions to the low-point problem, and each one would solve the problem
in a fundamentally different manner. Consequently, their complexity and the time
that would be required to implement each one also vary widely.
36
Successful implementation of any individual alternative may depend on external
conditions—such as permitting, successful negotiation between the agencies and
institutions involved, and/or availability of financing—that are beyond the control
of the project proponents. As a result, it may be necessary to pursue several different
alternatives in parallel or as part of an “umbrella” program leading to a long-term
plan. This strategy would provide maximum flexibility to react to the risks and
uncertainties inherent in any major water resources program in California.
As described in Section 2, the reformulation and refinement of alternatives is an
ongoing part of the project development and the planning process. Therefore, as
feasibility evaluations proceed, additional variations or combinations of alternatives
not included in the descriptions provided in this report may be identified.
Section 6
Next Steps
The next steps in the Low-Point Improvement Project studies will be to complete engineering and environmental investigations for the recommended feasible alternatives.
Both of these processes will include further outreach to stakeholders and regulatory
agency representatives, and the environmental review process will also provide more
opportunity for public input and comment. The result of these studies now in progress
will be a draft engineering feasibility study and a draft environmental impact report/
environmental impact statement.
Engineering Studies
Engineering studies will include more detailed technical analyses, operational modeling,
surveying, geotechnical investigations, and estimation of project benefits and costs.
Potential institutional and financial arrangements for project implementation will also
be identified. In accordance with the CALFED principle stipulating that “beneficiaries
pay,” project costs will be allocated among potential partners in proportion to the
benefits they would receive.
Some of the most important technical issues that need to be resolved for each of the
feasible alternatives are summarized in the table on the following page.
Environmental Studies
The focus of SCVWD’s upcoming environmental studies will be preparation of a
combined environmental impact report/
environmental impact statement for joint
compliance with CEQA and NEPA. SCVWD
will serve as the lead agency for CEQA
compliance, and the U.S. Bureau of Reclamation will serve as the lead agency for
NEPA compliance. The “joint compliance”
approach was selected because combining
the CEQA and NEPA review processes typically saves money by eliminating duplication of effort. At the same time, because
the requirements of the state and federal
regulations differ slightly, joint compliance usually results in a more comprehensive environmental analysis than that
required for either law alone.
37
Section 6
��
��
��
• Evaluate the relative effectiveness of algicide application and algae harvesting for San Luis
Reservoir.
• Identify any permitting needs and application restrictions that are relevant to algicide
application.
• Determine the disposal method and identify disposal site(s) for harvested algae material.
��
• Assess the effectiveness of DAF treatment for algae removal in water from San Luis
Reservoir.
• Determine whether a centralized or decentralized approach is most appropriate for
implementation of this alternative.
- Confirm the feasibility of a centralized treatment site near the Pacheco Pumping Plant.
38
- If a decentralized approach is selected, identify potential sites for DAF treatment
in SBCWD and PVWMA service areas and confirm the feasibility of using San Luis
Reservoir water for upstream groundwater recharge and agricultural diversions.
��
��
• Evaluate the effectiveness of extending and lowering the existing Pacheco intake without
lowering the Pacheco Pumping Plant.
• Determine method of construction and connection to existing facilities.
• Identify measures to ensure that San Felipe Division's water supply reliability objectives
would be met.
��
��
• Confirm the preferred location for a new intake and pump station.
• Identify the preferred route and method of conveyance.
• Evaluate the availability, reliability, and quality of water diverted from the Delta-Mendota
Canal during the low-point months.
��
��
• Identify the preferred dam site.
• Identify route, method of conveyance, and pumping station location.
• Use operational modeling to refine the required reservoir storage volume.
��
��
• Identify the feasibility, timing, and cost of the regional projects that would likely be
included in this alternative.
• Assess potential risks to water supply reliability from reoperation of existing facilities.
��
• Define baseline conditions for CALFED Program through the Common Assumptions Work
Group.
• Estimate costs to industry and agriculture from potential interruption of water supply
during the low-point months.
Section 6
Project EIR/EIS
The purpose of the upcoming environmental impact
report/environmental impact statement for the LowPoint Improvement project will be to
• address physical, biological, and human environmental resources;
What Do CEQA and NEPA Require?
CEQA requires the preparation of an environmental impact
report when a project has the potential to result in significant environmental impacts. The trigger for preparation of
an environmental impact statement to comply with NEPA
is very similar.
• analyze the potential environmental effects of the
various alternatives, including possible contributions to cumulative impacts in the project area;
Under CEQA, an environmental impact report must
• inform decision makers and the public about a project’s
significant environmental effects, and
• describe both adverse impacts and anticipated
benefits;
• identify project alternatives and mitigation measures that
would reduce the project’s effect on the environment.
• identify mitigation measures to avoid or compensate for significant adverse effects, and
Under NEPA, an environmental impact statement must
• provide opportunities for public participation in
the planning and decision making process, including a public meeting following the release of the
draft document for public review.
Stakeholder Outreach
As the detailed engineering and environmental studies proceed, SCVWD will continue to hold meetings
with the Stakeholder Committee and the Regulatory
Compliance Work Group. Meetings will be timed with
key milestones in the studies to provide updates
and gather feedback. Additional briefings will be
provided to agencies, environmental organizations,
and other interest groups. At least one public
meeting will be held following release of the draft
environmental document, which is currently planned
for 2004.
• disclose the potential environmental impacts of the proposed project,
• identify any adverse environmental effects that would be
unavoidable if the proposed project were implemented,
• identify alternatives to the proposed project,
• discuss the project’s effect on the relationship between
local short-term uses of the environment and the maintenance and enhancement of long-term productivity, and
• identify any irreversible and irretrievable commitments of
resources that would result from implementation of the
proposed project.
39
Section 6
40
1. San Luis
Reservoir
Flexibility
Concepts
2. San Felipe
Division Water
Supply
Reliability
3. San Felipe
Division Water
Quality
4. Technical
Feasibility
Results
Concepts
That Meet
All Criteria
Candidates for
Combination
Solution
Notes
No Action
Not rated, required for CEQA/NEPAcompliance.
No Project/No Action
Institutional Agreements
Banking
Contract Amendment with USBR
Exchanges
Operating Agreements and Procedures
Rescheduling
May provide some short-term benefits.
Limiting drawdown to 300 TAF reduces operational flexibility of reservoir.
Source Water Quality Control
Algae Harvesting
Algicides/Herbicides (For algae or macrophytes)
Barley Straw (To absorb algae and nutrients)
Coffer Dam Around Intake
Dilution/Flushing (Local runoff)
Dredging
Fish Grazers on Algae or Macrophytes
Floating Covers
Intermediate Intake for Pacheco Pumping Plant
Isolate Portion (Arm) of San Luis Reservoir
Macrophyte (Water weed harvesting)
Managed Stratification (Modify Gianelli Inlet/Outlet Works)
Mechanical Destratification and Lake Mixing
Nutrient Harvesting from Fish or Other Biota
Oxygenation or Aeration
Pathogens of Algae or Macrophytes
Raise San Luis Reservoir
Sediment Sealing (Fabric liners, barriers, chemicals)
Shading (Dyes) to Minimize Light for Photosynthesis
Use Calero as Wetland
Water Level Fluctuation
Wetlands Algae Filter (Off-line wetlands)
Testing required to develop site specific design criteria.
Commonly used method, may have permitting issues.
Not technically feasible for this size reservoir.
Algae accumulation within coffer dam would degrade water quality.
Local runoff volume is not sufficient.
Not applicable to this problem, bottom is not anoxic.
Fish will not eat blue-green algae, change type of fish in reservoir.
Not feasible for large reservoir, water quality under cover could degrade.
New intake would be above lower intake and provides no benefit.
Removes 200 TAF from storage, stops circulation and could degrade water quality.
Not applicable to this problem, algae not weeds create problem.
Potential water quality issues for South of Delta contractors.
Difficult for large reservoirs, similar to oxygenation and aeration.
Fish represent small percentage of biomass, removes fish from reservoir.
Difficult for large reservoirs, similar to mechanical destratification and lake mixing.
Short-term benefits, algae build up immunity to pathogens.
Reliability problem remains for San Felipe Division if minimum pool reached early in season.
Not applicable to this problem, bottom is not anoxic.
Reservoir is too large for dyes, wind would disperse dyes.
Eliminates Calero Reservoir as storage facility.
Not applicable to this problem, algae not weeds create problem.
Not technically feasible for this size reservoir.
Water Treatment
Dissolved Air Flotation (DAF) Near San Felipe Intake
DAF at Coyote Pumping Plant (Plus San Benito and Pajaro)
DAF at Santa Teresa and Rinconada (Plus San Benito and Pajaro)
Testing required to establish site specific design criteria.
Conveyance
Extend/Lower San Felipe Intake to Gianelli Inlet/Outlet Level
Highway 152 Pipeline/Tunnel
Holladay Aqueduct
Northerly Bypass Corridor
Southerly Bypass Corridor
Ranney Collectors in San Luis Reservoir
Facilities in Southerly Bypass Corridor, include as option.
Right-of-way, permitting, and safety issues limit technical feasibility.
Concept similar to Northerly Bypass Corridor, consider as option.
Requires multiple pump stations and construction in rugged terrain.
Multiple options for facilities and locations within this corridor.
Bottom geology not suitable for this technology.
continued
Notes:
(a)
= Meets criterion,
= Partially meets criterion, and
= Does not meet criterion.
(b) Water conservation and wastewater reclamation and reuse are precedents to any concept.
Exhibit I
(c) Opportunities for project-related environmental and other improvements would be considered for any concept.
(d) A concept may be a candidate for combination if: (1) It may be reasonably combined to formulate a viable solution,
and (2) It meets the criterion for Technical Feasibiltiy.
San Luis Reservoir Low Point Improvement Project
Level 1 Screening Matrix
1. San Luis
Reservoir
Flexibility
Concepts
2. San Felipe
Division Water
Supply
Reliability
3. San Felipe
Division Water
Quality
4. Technical
Feasibility
Results
Concepts
That Meet
All Criteria
Candidates for
Combination
Solution
Notes
Local Reservoir Storage
More Storage at Existing Dam and Reservoir Sites
Almaden
Anderson
Calero
Chesbro
Coyote
Guadalupe
Lexington
Lower Pacheco
Pacheco A
Pacheco B
Stevens Creek
Upper Pacheco
Uvas
Vasona
New Dam and Reservoir Sites
Ausaymas
Blue Ridge
Cedar Creek
Clarks Canyon
Coe
Harper
Los Osos
North Fork Pacheco
Packwood
San Felipe
Smith Creek
South Fork Pacheco
Inefficient site. Does not meet elevation constraint.
Inefficient site. Does not meet conveyance distance and elevation constraints.
Inefficient site. Lack of suitable construction materials. High liquefaction potential.
Does not meet conveyance distance and elevation constraints.
Inefficient site.
Meets all physical constraints.
Inefficient site. Does not meet conveyance distance or elevation constraints.
Does not meet conveyance distance or elevation constraints.
Alternate Water Supplies
Desalination - Monterey Bay
Desalination - San Benito Groundwater Basin
Desalination - San Francisco Bay
Desalination - SB Groundwater Basin, SF Bay, and Monterey Bay
EBMUD Freeport Project
Enlarged SBA/Los Vaqueros Reservoir Expansion
Los Vaqueros Reservoir Expansion
More Storage in SCVWD Groundwater Basin
Options from SBCWD Basin Management Plan
Options from PVWMA Basin Management Plan
Re-Operation of Anderson Reservoir
SFPUC Expanded Calaveras Reservoir
SFPUC Intertie (s)
Inefficient site. Indundates Twin Creeks. New Almaden directly downstream.
Meets all physical requirements. More study needed on UTC site and inundation of residences.
Complex construction with four saddle dams and areas high liquefaction potential.
Inefficient site. Complex construction with four saddle dams.
Inefficient site. Complex construction with four saddle dams. Fault beneath left abutment.
Inefficient site. Does not meet elevation constraint. Faults beneath expanded site.
Does not meet conveyance distance constraint. Would require relocation of Highway 17.
Meets all physical constraints. One of four dam sites at Pacheco Creek.
Inefficient site. Does not meet conveyance distance constraint.
Does not meet conveyance distance constraint. Dam site in area with high liquefaction potential.
Does not meet conveyance distance constraint. Would inundate portions of Los Gatos.
TBD
TBD
Notes:
(a)
= Meets criterion,
= Partially meets criterion, and
= Does not meet criterion.
(b) Water conservation and wastewater reclamation and reuse are precedents to any concept.
TBD
TBD
TBD
TBD
TBD
TBD
Provides replacement water during low point supply interruption.
Safe yield not sufficient to supply all San Felipe Division contractors.
Supply limited, especially during dry years.
Studies in progress.
Studies in progress.
Groundwater basin is fully utilized for SCVWD.
Further study required.
Further study required.
Would require additional studies of system operations and risks.
Studies in progress, supply may be limited.
Existing intertie is for emergency use only.
Exhibit I
(c) Opportunities for project-related environmental and other improvements would be considered for any concept.
(d) A concept may be a candidate for combination if: (1) It may be reasonably combined to formulate a viable solution,
and (2) It meets the criterion for Technical Feasibiltiy.
San Luis Reservoir Low Point Improvement Project
Level 1 Screening Matrix
San Francisco Bay
Desalination Plant
(Location TBD)
South Bay Aqueduct
Other Regional Projects:
Expanded Los Vaqueros Reservoir
Expanded Calaveras Reservoir
Desalination/Demineralization
SBCWD and PVWMA Options
Penitencia WTP
Hetch Hetchy Aqueduct
East Pipeline
Central
Pipeline
West
Pipeline
Delta-Mendota Canal
Snell Pipeline
Stevens Creek
Pipeline
California Aqueduct
Vasona
Pump Station
Expand Anderson Reservoir
DAF at Rinconada WTP
Calero Pipeline
Almaden Valley
Pipeline
Northerly Bypass Corridor
DAF at Santa
Teresa WTP
Henry Coe State Park
Cross Valley
Pipeline
Expand Pacheco
Reservoir
DAF at Coyote
Pumping Plant
Managed Stratification
Santa Clara
Conduit
Los Osos
Reservoir
San Luis
Reservoir
Algae Management
Algicide Application
Algae Harvesting
Pacheco Conduit
DAF at Pacheco
Pumping Plant
Santa Clara Tunnel
Proposed Pajaro
Import Pipeline
Lower San Felipe Intake
(Independent of
Low Point Improvement
Project)
DAF for SBCWD
and PVWMA
(Location TBD)
Monterey Bay
San Luis Canal
Hollister Conduit
Well Field and Demineralization Plant
(Location TBD)
San Justo Reservoir
Key: Alternative labels in box indicate that alternative
N
Alternative labels without a box indicate that alternative has
been eliminated from further consideration e.g.
Los Osos
Reservoir
SCALE IN MILES
0
2
Exhibit II
Alternatives Location Map

San Luis Reservoir Low Point Improvement Project Draft

Transcription

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