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LandWatch Monterey County and the Monterey Peninsula League of Women Voters have undertaken together this summary of water supply projects for Monterey County. While the League for many years has played a central role in providing objective analysis of county water issues, and at times it has played an advocacy role on theses issues, the same is not true for LandWatch.

LandWatch Monterey County is primarily focused on land use policy, not water politics. Nonetheless, the complex technical, fiscal and political challenges related to water quality, supply and distribution throughout Monterey County are inextricably linked to important land use issues. Although LandWatch has not taken a position on political decisions related to water issues in the past, it is important for LandWatch and its members to stay informed about the current status of proposed water solutions, which have been complex and convoluted in their evolution and not easily grasped. In an effort to stay abreast of these very important water issues, LandWatch has joined with the League of Women Voters in the preparation of this “Summary of Water Supply Projects for Monterey County.”

Sources of Water
Groundwater is the primary source of water to meet agricultural and urban needs in Monterey County. Stream percolation and rainfall are the primary sources of most of the groundwater recharge. Major streams include the San Antonio, the Nacimiento, Salinas, Carmel and Big Sur Rivers and the Pajaro River.

Salinas Groundwater Basin
The Salinas Groundwater Basin extends from Bradley to the Pacific Ocean. The Basin has been in a state of overdraft for over 60 years with the intruded area approaching the cities of Salinas and Marina, Castroville, and former Fort Ord. Over 90% of the water is used for agriculture.

The Monterey Regional Water Pollution Control Agency (MRWPCA) and Monterey County Water Resources Agency currently operate a program that provides tertiary treated reclaimed water from the Regional Wastewater Treatment Plant in Marina to irrigate agricultural land in the Castroville area. This project has been in operation for over ten years and is one of a few in the nation.

The Salinas Valley Water Project, currently under construction, includes spillway modifications at Nacimiento Dam and re-operation of the Nacimiento and San Antonio Reservoirs. The project also includes the diversion of water from the Salinas River. The facility would include an inflatable dam designed to operate from April to November and a diversion facility that would divert river water to the existing Castroville Seawater Intrusion Project system. This project is intended eventually to halt but not reverse seawater intrusion in the Castroville area. The water from this project is to be used by Salinas Valley land owners. The water will not meet potable water standards.

Additional modifications to the system would be needed to reverse intrusion; however, development of these modifications is uncertain due to stream-flow requirements established by the National Oceanic and Atmospheric Agency (NOAA) to protect stealhead fisheries, and lack of funding.

North Monterey County
The North County area is comprised of the Monterey County portion of the Pajaro Basin, the Elkhorn Coastal Plain and the Hilly Area including Prunedale. Except for the extreme southwestern portion of North County, the only source of groundwater recharge is rainfull. This area has significant water supply and water quality problems in many of its aquifers, including falling water levels in its eastern areas, seawater infiltration and intrusion in the western areas, and nitrate ion contamination due to septic tank proliferation and the historic use of commercial fertilizers. The Pajaro Basin is in overdraft and suffers from seawater intrusion.

No projects have been approved to address water supply in North Monterey County. The largest public water agency in the area is the Pajaro-Sunny Mesa Community Services District which is developing four major new replacement projects to address localized water contamination problems and restore former ALCO water systems awarded to the District by the United States District Court. The District has also proposed a desalination plant at the former National Refractories site to provide water to North Monterey County and the Monterey Peninsula. This project is currently is moving very slowly. The future of the Pajaro Valley Water Management Agency which was intended to manage the Pajaro Basin is uncertain because of legal and funding problems.

Monterey Peninsula
In the early 1990s, population growth on the Monterey Peninsula surpassed the number of people who could be served under California American Water’s (Ca-Am’s) production limits. Based on these limits, an estimated population of 96,674 people could be supported within the CalAm system. The 1995 population estimate for the service area was 98,898.

The State Water Resources Control Board (SWRCB) ruled in 1995 that CalAm was diverting over 10,000 acre-feet per year from the Carmel River without valid rights and that CalAm must remedy this situation (Order 95-10). The SWRCB has issued a draft Cease and Desist Order because little if any progress has been made to meet Order 95-10. The draft order would require water rationing until alternative water supplies become available. The final order is expected in the fall of 2008.

The 20-square-mile Seaside Groundwater Basin underlies the cities of Seaside and Sand City; and parts of the cities of Del Rey Oaks and Monterey, former Fort Ord and the Highway 68 corridor including Ryan Ranch, Hidden Hills and Laguna Seca. The Basin provides water for about 25% of the CalAm distribution system, the City of Seaside municipal system, two golf courses in the Seaside area, and several industrial users. The Basin is overdrafted and is managed by a Watermaster Board pursuant to adjudication in 2006. The purpose of the Board is to ensure the Basin is protected and managed as a perpetual source of water for beneficial uses.The Watermaster is preparing the second phase of implementation of the Seaside Basin Management Plan. This work will include a comprehensive Basin Management and Action Plan which is currently scheduled for approval by the Watermaster Board in November 2008

Several small projects have been developed and/or identified to provide incremental solutions to water supplies for the Monterey Peninsula. Most major golf courses on the Monterey Peninsula are irrigated with reclaimed water. The Monterey Peninsula Water Management Agency and CalAm have a water conservation program that has reduced per capita demand to one of the lowest in California. The Aquifer Storage and Recovery project (ASR) for the Seaside Basin diverts treated excess Carmel River winter flow via existing CalAm pipelines to wells in the Seaside Basin. This project will yield over 1,000 AFY annually when completed and may be expanded. The City of Sand City and CalAm are building a small desalination project to provide water for the City’s future use.

The proposed Regional Urban Water Project (RUWAP) between the Monterey Regional Water Pollution Control Agency and the Marina Coast Water District would supply reclaimed water to Marina, Seaside, Del Rey Oaks and Monterey for landscape irrigation. Treating the water for injection into the Seaside Groundwater Basin has also been studied. This project is currently stalled because the two agencies cannot resolve differences regarding implementation.

The Coastal Water Project proposed by CalAm would combine ASR with a desalination project located in Moss Landing or Marina. This project would provide water to meet requirements of Order 95-10 and replenishment of the Seaside Aquifer as well as water for growth on the Monterey Peninsula. The California Public Utilities Commission (PUC) is the lead agency and is currently preparing an environmental impact report to be released in late 2008 or early 2009. The Monterey Peninsula Water Management Agency is also considering a desalination plant in the Sand City area to supply enough water to address Order 95-10. A feasibility report is expected to be completed in September. An ocean-vessel desalination project has also been proposed; however, the project has no lead agency. Also, as noted above, the Pajaro-Sunny Mesa Community Services District has proposed a desalination project.

The Regional Plenary Oversite Group (REPOG) which is described below has proposed a countywide plan that would address water supply needs for the Monterey Peninsula.

Highway 68 Corridor
The El Toro Groundwater Basin is contiguous to the Seaside Groundwater Basin and is currently in overdraft. Ryan Ranch, Hidden Hills and Laguna Seca areas are served by water from the Seaside Groundwater Basin. CalAm owns most of the water systems along the corridor. Solutions to water supply problems for this area are related to the management of the Seaside Groundwater Basin.

Countywide Water Supply Projects
Various projects to address countywide water needs have been considered over the last 40 years. These projects included importation of State water and a dam on the Arroyo Seco River, but they were rejected for a variety of reasons.

Recently, a new proposal to address countywide issues has emerged. It grew out of the Regional Plenary Oversite Group (REPOG) which was established by the PUC Division of Ratepayers to develop an alternative to CalAm’s Coastal Water Project. It should be noted that the PUC has no authority over the public water agencies including North County public water systems that are not currently program participants. Water for Monterey County, REPOG’s new name, focuses on the integration of local water projects that are under consideration and/or currently implemented into a regional program. Studies are underway to determine how the regional project would be implemented and funded. Full project implementation would depend on agreements among numerous water agencies, surrendering of historic groundwater rights held by affected public agencies, mutual water companies and overlying landowners; and satisfaction of legal funding requirements (Proposition 218). The project is intended to meet the needs of Order 95-10 and of the Seaside Aquifer; provide 4,500 additional AFY for growth on the Monterey Peninsula; provide 2,700 AFY to Marina Coast Water District and the Ord Community, 4,900 AFY to North Monterey County, and 1,000 AFY to Castroville.

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posted 10.21.08

LandWatch's mission is to protect Monterey County's future by addressing climate change, community health, and social inequities in housing and infrastructure. By encouraging greater public participation in planning, we connect people to government, address human needs and inspire conservation of natural resources.



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