00-5105. Notice of Intent To Prepare a Draft Environmental Impact Statement for the Proposed Salinas Valley Water Project, Monterey County, CA

AGENCY:

U.S. Army Corps of Engineers, DoD.

ACTION:

Notice of Intent.

SUMMARY:

The U.S. Army Corps of Engineers (USACE), San Francisco District, has received an application for a Department of the Army authorization from the Monterey County Water Resources Agency (MCWRA) to construct a surface water diversion structure in the Salinas River near the City of Salinas, Monterey County, California, as part of the Salinas Valley Water Project (SVWP). In accordance with the National Environmental Policy Act (NEPA) of 1969 (42 U.S.C. 4321 et seq.), the USACE has determined that the proposed action may have a significant impact on the quality of the human environment and therefore requires the preparation of an Environmental Impact Statement (EIS). A combined Environmental Impact Report (EIR)/EIS will be prepared with USACE as the Federal lead agency and the MCWRA as the local lead agency (under the California Environmental Quality Act, of CEQA).

The purpose of the proposed action is to provide for the long-term management and protection of groundwater resources in the Salinas River Basin by meeting the following objectives: Stopping seawater intrusion; Providing adequate water supplies to meet current and future (year 2030) needs; and Hydrologically balancing the groundwater basin in the Salinas Valley. The proposed action would: (1) Provide a source of water to the Basin by changing the operational programs (rule curves) of the upstream Nacimiento and San Antonio reservoirs, and capturing water from April through November via a surface diversion structure (inflatable dam) to provide water for agriculture; and (2) maintain and increase present conservation release practices to recharge the groundwater basin.

DATES:

A scoping meeting for this project will be held on April 5, 2000, 3:30 p.m. to 5:00 p.m.

ADDRESSES:

The scoping meeting will be held at the Monterey County Water Resources Agency, 893 Blanco Circle, Salinas, California 93901-4455. Mail comments to: Robert F. Smith, U.S. Army Corps of Engineers, 333 Market Street, CESPN-OR-R, San Francisco, CA 94105-2197, or; Curtis Weeks, Interim General Manager, Monterey County Water Resources Agency, 893 Blanco Circle, Salinas, California 93901-4455.

FOR FURTHER INFORMATION CONTACT:

Robert Smith, 415-977-8450, or electronic mail: [e-mail]. Curtis Weeks, 831-755-4860.

SUPPLEMENTARY INFORMATION:

Groundwater is the source for almost all of the water needs (agricultural and urban) in the Salinas Valley Groundwater Basin. In the northern coastal areas of the Basin, most groundwater extraction occurs from two groundwater supplies, the 180-Foot and 400-Foot Aquifers. An ongoing imbalance between the rate of groundwater withdrawal and recharge has resulted in overdraft conditions in the Salinas Valley Groundwater Basin that have allowed seawater from Monterey Bay to intrude inland into both of these aquifers in the northern Salinas Valley. By 1995 seawater was estimated to affect as much as 19,788 acres overlaying the 180-Foot Aquifer and 9,797 acres overlaying the 400-Foot Aquifer. As a result, urban and agricultural supply wells have been abandoned or destroyed in some locations. To halt further groundwater degradation and prevent seawater from moving further inland, aquifer pumping and recharge rates would need to be brought into balance.

Water needs, both existing and future, were considered as an integral part of the development and design of the proposed action. Without the development of water supplies to augment existing groundwater supplies, both existing and future water needs (the year 2030 was used for the future planning horizon) would result in further Basin overdraft and seawater intrusion.

1. Description of Proposed action: The project area is located in Monterey County and northern San Luis Obispo County (Lake Nacimiento's location), California. The following specific project components are being proposed:

a. Nacimiento Spillway Modification: The proposed spillway modification would increase the flexibility of reservoir operations by altering the flood rule curve to maintain higher water levels during the winter and spring months. The additional storage gained at Nacimiento would be released for Basin recharge and diversion later in the year. The existing spillway would be modified by lowering the spillway crest by approximately 8 feet and installing an inflatable rubber dam or radial gates. In anticipation of a significant storm, the rubber dam/gates would be deflated/opened, increasing the capacity of the existing spillway to safely pass the event. Once the event has ended or at a point late in the winter season, the rubber dam/gates would be inflated/closed to restore reservoir water levels.

b. Reoperation of Reservoirs: The operation of the Nacimiento and San Antonio reservoirs serves two purposes: flood control and conservation (groundwater recharge through the Salinas River). The proposed spillway modification of Nacimiento would allow changes in the ways both reservoirs are operated (timing/quantity of water releases) in order to provide the source water for the action, while assuring the provision of adequate flood control capacity and at the same time maximizing conservation releases. Reoperation would involve changes to operational programs (rule curves) rather than physical improvements.

c. Salinas River Recharge, Conveyance and Diversion: The Salinas River would continue to provide for the recharge of the groundwater basin, and would serve as conveyance for a proposed downstream diversion facility. The diversion facility would include an inflatable dam that is proposed to operate from April to November. The proposed surface diversion facility would divert water in the Salinas River at Salachi Ranch Road into the existing Castroville Seawater Intrusion Project (CSIP) distribution pipeline for delivery to agricultural users for irrigation. The diversion facility would impound water an estimated 2 miles upstream when the dam is operational. The CSIP pipeline could potentially require expansion (i.e., enlargement of the irrigation service area) to facilitate the use of all the water to be diverted by the diversion facility.

d. Delivery Area Pumping Restrictions: Pumping restrictions would be imposed within the project delivery areas to avoid unregulated pumping by those who receive direct water deliveries from the proposed action.

2. Reasonable Alternatives: In accordance with the requirements of section 15124 of the State CEQA Guidelines and 40 CFR 1502.14, reasonable alternatives to the proposed action will be evaluated in the Draft EIR/EIS as listed below:

a. Proposed Action (Preferred Alternative): This alternative is the proposed action and is described above.

b. Subsurface Diversion: This is the alternative generally evaluated in the 1998 Draft EIR. This alternative would include the following components: (1) Modification of the Nacimiento Spillway; (2) reoperation of the Nacimiento and San Antonio reservoirs; (3) subsurface diversion, storage and use of Salinas River water; (4) treatment and delivery (to agricultural and possibly urban uses); (5) storage of recycled water (produced during low irrigation demand periods by the Monterey County Water Recycling Projects) in either the groundwater basin or a surface reservoir and delivery to agricultural uses during the irrigation season; and (6) delivery area pumping restrictions. This alternative differs from what was addressed in the 1998 Draft EIR in that it does not include a nitrate management plan.

c. Alternative Location: This alternative would be the same as the proposed action, except that the in-stream surface diversion facility would be developed at a different location in the Salinas River. The location of the diversion facility under this alternative will be determined after initial evaluation of the environmental effects of the diversion facility under the Proposed Action, with attention given to an alternative site which could reduce any significant environmental effects of the diversion facility under the Proposed Action.

d. No Action—No Action: Under this alternative, the MCWRA would implement no actions to address seawater intrusion and hydrologic balance in the Basin, while future water needs would occur as project.

e. No Action—Total Demand Management: This alternative assumes that in the event that the proposed action would not proceed, the MCWRA would implement forced reductions in groundwater pumping to stop seawater intrusion and bring the Basin into hydrologic balance.

f. No Action—State Adjudication: Implementation of this alternative would result in judicial control over the water resources in the Basin to include possibly: (1) Some type of restriction on water use; (2) reservoir reoperation; (3) forced conservation; or (4) reclamation.

3. Scoping Process: Pursuant to CEQA and NEPA, the MCWRA and USACE must include a “scoping” process for the Draft EIR/EIS. Scoping primarily involves determining the scope of issues to be addressed in the Draft EIR/EIS and identifying the anticipated significant issues for in-depth analysis. The scoping process includes public participation to integrate public needs and concerns regarding the proposed action into the process.

a. Public Involvement Program: Vehicles for public comment on the proposed action will include: a public workshop to be conducted jointly by the MCWRA and USACE; the preparation of the Draft EIR/EIS and receipt of public comment in response to the Draft EIR/EIS; and public hearings.

b. Significant Issues to be Analyzed in Depth in the Draft EIR/EIS: The following significant environmental issues have already been identified and will be analyzed in depth in the Draft EIR/EIS:

(1) Hydrology: The effect of the proposed action on Basin groundwater balance, seawater intrusion, groundwater levels, stream flows, reservoir storage levels, surface water levels, downstream flooding potential, and sediment transport will be evaluated.

(2) Public Health and Safety: The water quality and flooding effects of the proposed action will be evaluated. The regulatory requirements/impacts of development of the proposed surface diversion facility in the Salinas River will be evaluated.

(3) Fisheries. The influence of the proposed action on existing fishery resources in Nacimiento and San Antonio reservoirs, the Salinas River and its major tributaries, and the Salinas River Lagoon will be evaluated. In this evaluation, special attention will be given to sensitive and listed species such as steelhead, Oncorhynchus mykiss.

(4) Terrestrial Biological Resources: The potential for the proposed action to affect terrestrial biological resources at the Nacimeinto and San Antonio Reservoirs, the Salinas River and its tributaries, and the Salinas River Lagoon will be evaluated. Special attention will be given to sensitive and listed species such as least Bell's vireo (Vireo bellii pusillus), California red-legged frog (Rana aurora draytonii), and bald eagle (Haliaeetus leucocephalus).

c. Environmental Review/Consultation Requirements:

• National Environmental Policy Act.
• Section 404 of Clean Water Act.
• Section 10 of Rivers & Harbors Act.
• Endangered Species Act.
• Magnuson-Stevens Act Provisions; Essential Fish Habitat.
• Clean Air Act.
• National Historic Preservation Act.
• Fish and Wildlife Coordination Act.
• Coastal Zone Management Act.
• Council on Environmental Quality Memorandum—Analysis of Impacts on Prime and Unique Agricultural Lands.

4. Scoping Meeting/Availability of Draft EIR/EIS: The MCWRA and the USACE will hold a scoping meeting to provide information on the project and receive oral comments on the scope of the document. The Draft EIR/EIS is expected to be available for public review in September 2000.

(Authority: 40 CFR part 1501.7)

Dated: February 18, 2000.

Calvin C. Fong,

Chief, Regulatory Branch.