JOINT UPDATE TO
THE STATE WATER RESOURCES CONTROL BOARD
ON THE STATUS OF AMENDMENT THREE TO
THE SUISUN MARSH PRESERVATION AGREEMENT
Suisun Resource Conservation District
Department of Fish and Game
Department of Water Resources
U.S. Bureau of Reclamation
April 21, 1998
Joint Update on SMPA Amendment Three April 21, 1998
INTRODUCTION / OVERVIEW
The Department of Water Resources (DWR) is updating the State Water Resources Control Board on the status of the proposed Amendment Three to the Suisun Marsh Preservation Agreement (SMPA), on behalf of the four parties of the SMPA, namely, DWR, the Bureau of Reclamation (USBR), Department of Fish and Game (DFG), and the Suisun Resource Conservation District (SRCD). The parties have concluded negotiations of the Amendment Three to the SMPA in which they identify supplemental actions consistent with the original SMPA objective to improve Marsh habitat on managed wetlands. Copies of Amendment Three and the revised Demonstration Document were provided to the SWRCB in preparation for this Workshop.
The parties believe that: (1) the actions in Amendment Three would meet western Suisun Marsh objectives of the 1995 Water Quality Control Plan (WQCP) for Cordelia and Goodyear sloughs; (2) those actions provide better protection for the entire Marsh; and (3) compliance stations S-35 and S-97 are no longer needed.
The parties to the SMPA have agreed in principle to the amendment, and on September 18, 1997, issued to the SWRCB a letter of intent to execute SMPA Amendment Three upon completion of environmental documentation under the California Environmental Quality Act (CEQA) and National Environmental Policy Act (NEPA). The parties have completed a draft Environmental Assessment / Initial Study which will be circulated for public review. Final review and certification of the document should occur soon.
In September 1997, DWR and USBR, with the endorsement of DFG and SRCD, petitioned the SWRCB to extend the date when compliance at stations S-35 and S-97, as specified in Order WR 95-6, would be effective. In October 1997, the SWRCB approved the petition, extending the date to April 1998. A second petition requesting an additional 180 days was approved in April 1998. The additional time will enable the SMPA parties to execute and begin implementing Amendment Three.
This update is organized as follows:
Purpose and Basis of Suisun Marsh Objectives
1995 WQCP, Order WR 95-6, and Program of Implementation of 1995 WQCP
The Original SMPA and Accomplishments
Changed Conditions Requiring Amendment Three / Consequences of No Action
Amendment Three: Purpose, Approach, and Actions / Equivalent Protection
Implementing Amendment Three
Differences with SWRCB Alternative 5
Conclusions and Recommendations
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Joint Update on SMPA Amendment Three April 21, 1998
PURPOSE AND BASIS OF SUISUN MARSH OBJECTIVES
The purpose of the Suisun Marsh salinity objectives is to provide water of sufficient quality to the managed wetlands to achieve soil water salinities capable of supporting the plants characteristic of a brackish marsh (see SWRCB Environmental Report, 1995 Bay/Delta Plan, Appendix 1, page IX-15, et seq.; and 1995 WQCP, p.40.).
The channel water salinity standards established in Decision 1485 are based on research by Mall (1969) and Rollins (1973), who investigated the salinity tolerance of alkali bulrush (Scirpus robustus) and other important waterfowl food plants in the Suisun Marsh. Results of the research identified maximum monthly mean applied water salinity that would provide an average of 90 percent of the maximum alkali bulrush seed production and a 60 percent seed germination rate. The SWRCB determined that channel water salinities would be reported as the mean of the two daily high tides because, without the use of pumps, wetland managers using gravity systems are only able to divert water at high tides.
DFGs testimony to the SWRCB for Decision 1485, described the affect of soil salinity and length of soil submergence in May on seed production. DFG recommended that the target soil salinity in May should be about 9 parts per thousand total dissolved solids for proper plant germination.
DFG used the salinity standards as guidelines for long-term management and maintenance of wetlands in Suisun Marsh, considering the guidelines to represent the most saline water that can be applied regularly to well-managed seasonal wetlands without loss of alkali bulrush seed production. SRCD prepared water management plans for each of the 158 privately managed wetlands in the Marsh in 1980-81. Water management recommendations and vegetation goals in the plans are based on findings from Rollins' studies. The application of channel water to managed wetlands affects soil salinities throughout the October through May control season. As such, the effect of October channel water salinity is generally not apparent until later in the season.
1995 WQCP, ORDER WR 95-6, AND
PROGRAM OF IMPLEMENTATION OF 1995 WQCP
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Joint Update on SMPA Amendment Three April 21, 1998
In June 1995, the Board issued Order WR 95-6 to temporarily modify certain terms and conditions of Board Decision 1485 imposed on SWP and CVP water rights to conform these requirements with the new fish and wildlife standards for the Bay-Delta Estuary set forth in the 1994 Principles for Agreement on Bay-Delta Standards Between the State of California and the Federal Government (Bay-Delta Accord). As part of WR 95-6, the Board revised the Suisun Marsh standards to be consistent with the Boards 1995 Bay-Delta Water Quality Control Plan. Under both D-1485 and WR 95-6, the Marsh water quality standards may be met by either complying with specified in-channel Electrical Conductivity values or by demonstrating equivalent or better protection will be provided at the locations.
In the Program of Implementation of the 1995 Bay/Delta Plan, the SWRCB suggested that the DWR, USBR, DFG, and SRCD implement measures to appropriately control Suisun Marsh soil and channel salinities, including use of water and land management practices and the employment of a water manager to provide more consistent protection for the managed wetlands in Suisun Marsh and the species they support, and to protect the beneficial uses of water more efficiently than under current practices.
THE ORIGINAL SMPA AND ACCOMPLISHMENTS
The original SMPA, signed in 1987 by the USBR, DWR, DFG, and SRCD, was developed to provide facilities that would protect the brackish water nature of the Marsh, while mitigating for the effect on the managed wetlands of Suisun Marsh of operating the Central Valley Project (CVP) and State Water Project (SWP) and from other upstream water diversions. DWR, USBR, and DFG also signed two companion agreements on March 2, 1987: the Suisun Marsh Mitigation Agreement and the Suisun Marsh Monitoring Agreement.
The express objectives of the original SMPA remain the same today as in 1987. The SMPA objectives and provisions are consistent with the SWRCB permit conditions but may not encompass all SWRCB requirements for the Marsh, such as tidal wetlands. In the original SMPA, the parties agreed to focus primarily on managed wetlands.
To meet these objectives, the original SMPA established channel water salinity standards and a process for scheduling construction of large-scale facilities in Suisun Marsh that would enable the salinity standards to be met. USBR and DWR had responsibility for funding and constructing the facilities and for meeting the salinity standards. Construction of the facilities was to be in phases, based on evaluation of need and effectiveness of the facility previously constructed.
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Joint Update on SMPA Amendment Three April 21, 1998
The parties to the SMPA have worked cooperatively since the early 1980s to implement the Plan of Protection for the Suisun Marsh (1984), developed in response to Condition7 of D-1485. As required by the original SMPA, DWR and USBR constructed the Suisun Marsh Salinity Control Gates (SMSCG) in 1988. They constructed the Cygnus Unit in 1991, and the Lower Joice Island Unit in 1993. These facilities were in addition to the Initial Facilities constructed in 1980: Morrow Island Distribution System, Roaring River Distribution System, and the Goodyear Slough Outfall, as required by Condition 7(c) of D-1485. In 1990, the agencies began planning the Western Suisun Marsh Salinity Control Project, the objective of which was to develop facilities or activities in the western Marsh that would enable meeting D1485 channel water salinity standards in that area of the Marsh.
CHANGED CONDITIONS REQUIRING AMENDMENT THREE /
CONSEQUENCES OF NO ACTION
In July 1995, USBR, DWR, DFG, and SRCD agreed to open negotiations to amend the Agreement, to better reflect the following changed conditions.
1. In 1994, the Principles of Agreement on Bay-Delta Standards between the State of California and the federal government was signed, initiating a process to implement a Bay-Delta protection plan through the SWRCB. In May 1995, the SWRCB adopted a Water Quality Control Plan which calls for higher Delta outflows than those called for in D1485.
2. The SMSCG have been more effective at reducing salinity in Suisun Marsh than originally expected.
As a result of these changes: (1) DWR and USBR stopped work on planning and environmental documentation for the Western Suisun Marsh Salinity Control Project in April 1995; and (2) the SMPA parties agreed that additional large scale facilities proposed in the Plan of Protection will not be necessary for salinity control in the Suisun Marsh.
The parties arrived at these decisions based on data of channel salinities with SMSCG operation and from DWR model studies conducted in support of the 1995 Bay/Delta Plan and the SWRCB Draft EIR for its implementation. In summary, the field data and both model studies indicate that: (1) eastern and central Marsh salinity objectives would be met on most occasions by operating the existing Initial Facilities and the SMSCG under the 1995 WQCP flows/salinities, and (2) less frequent and lower exceedences of salinity objectives would occur in the western Marsh during dry and critical water years.
Consequence of No Action. The No Action Alternative would continue implementation of the original SMPA under the changed conditions that currently exist in the Suisun Marsh. Continued implementation would probably require some action or facility to control salinity in the western Marsh, and would mean significant delays in meeting the habitat and waterfowl food plant objectives for the western Suisun Marsh, as well as considerable environmental impacts associated with implementation of large-scale facilities in the Marsh.
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Joint Update on SMPA Amendment Three April 21, 1998
AMENDMENT THREE: PURPOSE, APPROACH, and ACTIONS /
EQUIVALENT PROTECTION
The purpose of Amendment Three to the SMPA is to change the Agreement to provide equivalent protection to Suisun Marsh managed wetlands as intended under the original SMPA, while recognizing the effects of increased Delta outflows and effective operation of the SMSCG. The Amendment will make the channel water salinity standards consistent with the SWRCBs 1995 WQCP and will replace large-scale facilities with water and land management activities to meet the objectives of the SMPA in the western Marsh.
The parties to the SMPA have determined that better use of channel water (quickly flooding at lowest salinity) and improved land management (improved drainage) are more effective in providing desired habitat than assuring specified channel water salinities. The management actions would assist landowners of managed wetlands in achieving soil salinities for improved growth of forage for waterfowl and wildlife on managed wetlands.
The objectives of the Amendment Three actions are to: (1) provide funds to wetland managers in impacted areas of the Marsh to re-establish a diverse plant assemblage and return soil salinities to levels characteristic of Suisun Marsh brackish soils; (2) maintain soil salinities within natural ranges as outlined by the Soil Conservation Service (1977); (3) improve water and wildlife habitat on managed wetlands throughout the Suisun Marsh; and (4) broaden mitigation activities to emphasize management, restoration projects, and studies to mitigate for impacts to listed and sensitive species.
The parties considered the following information in developing the actions of Amendment Three.
1. Importance and Consequences of Management. The benefits of active water management on the managed wetlands are significant and are reflected in the soil water salinity and vegetation diversity. Soil water and applied water salinity data collected on the managed wetlands were evaluated for the SMPA's Comprehensive Review. Water salinity in the eastern portion of the Marsh is consistently lower than salinity in the western portion. However, although applying channel water that was about twice as saline as the eastern Marsh channel water, West Family was able to achieve lower soil water salinity than some eastern Marsh clubs because it is actively managed. SRCD conducted a separate soil salinity study during 1996 at Tule Hilton, Ownership No. 412, in the western Marsh which also illustrates that soil water salinities are lower after a leach cycle is completed. Leaching is a critical component to an active water management strategy for controlling soil salt levels. Benefits of actively managing water are also reflected in the higher diversity of vegetation on the clubs.
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Joint Update on SMPA Amendment Three April 21, 1998
2. Effects of Water Management During Drought Conditions. Comparing two managed wetlands in the western Suisun Marsh during 1985-86, the period just before the 1987-92 drought, Goodyear Club (not actively managed) was able to achieve soil water salinities similar to West Family Club (actively managed) without active water management. However, beginning in 1987, the first critical water year, Goodyear Club consistently had significantly higher soil water salinity than West Family Club, indicating that once drought conditions are established, active water management is particularly critical to maintaining low soil water salinities.
3. Variability of Salinity at High vs. Low Tides. The majority of the managed wetlands fill during high tides using gravity flow. Salinity monitoring throughout the Marsh indicates, however, that at certain stations (regions) there is a significant salinity variation between high and low tides, while at other stations this difference is less pronounced or non-existent. In general, salinity is higher at high tide and lower at low tide. Managed wetlands that would benefit the most from using pumps to fill are those that experience the greatest variation in channel salinity during a tidal cycle. Observed data indicate that managed wetlands in a significant portion of the Marsh could fill with lower salinity water if they could pump water from the channel throughout the tide and/or selectively pump water during low tides.