NACIMIENTO WATER PROJECT Addendum No. 1 to Final Environmental Impact Report Prepared for: Revised November 2007 County of San Luis Obispo NACIMIENTO WATER PROJECT Addendum No. 1 to Final Environmental Impact Report Prepared for: Revised November 2007 County of San Luis Obispo 707 Wilshire Blvd. Suite 1450 Los Angeles, CA 90017 213.599.4300 www.esassoc.com Oakland Petaluma Portland Sacramento San Diego San Francisco Seattle Tampa Woodland Hills 204453 ADDENDUM Nacimiento Water Project Final EIR 1. Introduction This document is an Addendum to the Final Environmental Impact Report (Final EIR) prepared by San Luis Obispo County for the Nacimiento Water Project (NWP). The Final EIR evaluated the potential environmental effects of the NWP, which proposed construction of a water intake pump station at Lake Nacimiento Dam, 55 to 65 miles of water transmission pipeline, plus additional water storage tanks and pump stations. The Final EIR was certified on January 6, 2004 by the Board of Supervisors of the San Luis Obispo County Flood Control and Water Conservation District (SLOCFCWCD), which acted as the Lead Agency pursuant to the California Environmental Quality Act (CEQA) (CEQA Guidelines (Title 14, California Code of Regulations, Section 15300 et. seq.) §15090). Since the certification of the Final EIR, changes have been made to the project description for the NWP. Under CEQA, an addendum may be prepared when minor modifications are proposed for a project that has already been approved when no additional significant environmental impacts would result (CEQA Guidelines, §15164). This Addendum evaluates whether any new significant impacts would result from implementation of the proposed modifications. 2. Purpose of Addendum Under CEQA, the Lead Agency shall prepare an addendum to a previously certified Environmental Impact Report (EIR) if some changes or additions are necessary to the prior EIR, but none of the conditions calling for preparation of a subsequent or supplemental EIR have occurred (CEQA Guidelines §15164). Once an EIR has been certified, a subsequent EIR is only required when the Lead Agency determines that one of the following conditions has been met: (1) Substantial changes are proposed in the project, or substantial changes occur with respect to the circumstances under which the project is undertaken, which require major revisions of the previous EIR due to the involvement of new significant environmental effects or a substantial increase in the severity of previously identified significant effects (CEQA Guidelines §15162(a)(1), (2)); (2) New information of substantial importance, which was not known and could not have been known with the exercise of reasonable diligence at the time the previous EIR was certified as complete, shows any of the following: Nacimiento Water Project 1 ESA / 204453 EIR Addendum November 2007 a. The project will have one or more significant effects not discussed in the previous EIR; b. Significant effects previously examined will be substantially more severe than shown in the previous EIR; c. Mitigation measures or alternatives previously found not to be feasible would in fact be feasible and would substantially reduce one or more significant effects of the project, but the project proponents decline to adopt the mitigation measure or alternative; or d. Mitigation measures or alternatives which are considerably different from those analyzed in the previous EIR would substantially reduce one or more significant effects on the environment, but the project proponents decline to adopt the mitigation measure or alternative (CEQA Guidelines §15162(a)(3)). If one or more of the conditions described above for a subsequent EIR exist, but only minor additions or changes would be necessary to make the previous EIR adequately apply to the project in the changed situation, then the lead agency may prepare a supplement to an EIR, rather than a subsequent EIR (CEQA Guidelines §15163(a)). This Addendum has been prepared because the proposed modifications to the NWP do not meet the conditions for a subsequent or supplemental EIR. The modifications would not result in new significant environmental effects or change the conclusions of the previously certified Final EIR. An addendum does not need to be circulated for public review, but rather can be attached to the final EIR (CEQA Guidelines §15164(c)). At the time a project would be initiated, “[t]he decision making body [SLOCFCWCD] shall consider the addendum with the final EIR…prior to making a decision on the project” (CEQA Guidelines §15164(d)). A brief explanation of the decision not to prepare a subsequent or supplemental EIR should be included in an addendum or elsewhere in the record (CEQA Guidelines §15164(e)). 3. Nacimiento Water Project Overview The San Luis Obispo County Flood Control and Water Conservation District (SLOCFCWCD or District) proposes to construct the NWP, which includes the following: a water transmission pipeline from Lake Nacimiento to the City of San Luis Obispo; an Intake Pump Station at Lake Nacimiento Dam; two additional pump stations; and three water tanks. The Final EIR evaluates two scenarios for the NWP that vary in the water delivery and treatment options—a Treated Water Option and a Raw Water Option (See Figures 2-1 and 2-2, FEIR). The Treated Water Option includes construction and operation of a central Water Treatment Plan (WTP) near Lake Nacimiento on Camp Roberts’ property. The Raw Water Option does not include the central WTP but does include construction and operation of water discharge facilities. As described in the Final EIR, the NWP would supply up to 16,200 acre feet per year (afy) of water to various communities in San Luis Obispo County (SLO County). The District has a 17,500 acre-feet (af) annual entitlement from Lake Nacimiento per an agreement executed in Nacimiento Water Project 2 ESA / 204453 EIR Addendum November 2007 1959 with Monterey County. Of this 17,500 af entitlement, 16,200 af would be slated for this project, and the remaining 1,300 af would be reserved for local lakeside use. When the Final EIR was published, fifteen purveyors had submitted requests for 13,575 afy of Lake Nacimiento water. Subsequent to the completion of the Final EIR, the list has been reduced to just five entities: two cities, one community services district, one county-operated water system, and one mutual water company. The amount of water currently contracted is 9,655 afy. NWP Objectives The proposed NWP would meet the need for future water supplies in SLO County and supplement existing groundwater sources. The objective of the NWP is to ensure better management of available water resources throughout SLO County. By supplementing the local groundwater and surface water supplies with a new surface water source, it is hoped that the project will: • Provide a reliable supplemental water source for a variety of uses within SLO County. • Increase reliability of water deliveries. • Improve water quality. • Lessen the extent of future groundwater pumping to existing residents. • Provide sufficient supplies to support planning objectives in various communities of SLO County. The proposed modifications to the NWP facilities described below would contribute to the management of water resources in SLO County by delivering reliable, high-quality surface water and supporting the planning objectives of communities within the vicinity of the proposed project. 4. Proposed Modifications to the Project Description The District is proposing modifications to the NWP as described in the Final EIR, including pipeline alignment refinements, turnout location refinements, and pump station and storage tank modifications. All proposed modifications apply to the Raw Water Option scenario, which was approved by the Board of Supervisors of the SLOCFCWCD in January 2004. Descriptions of the modifications presented below are derived from the District’s NWP Preliminary Design Report from July 2006. 4.1 Water Customers The District has a 17,500 acre-feet (af) annual entitlement from Lake Nacimiento, of which the amount slated for the NWP has been modified to 15,750 afy. The amount of water to be reserved for local lakeside use has been modified to 1,750 af. Nacimiento Water Project 3 ESA / 204453 EIR Addendum November 2007 The Final EIR lists fifteen purveyors that have requested water from the NWP (See Table ES-1, FEIR). Currently, five purveyors, or Initial Participants, have executed Water Delivery Entitlement Contracts with the District (Table 1). The Initial Participants are the City of El Paso de Robles, Atascadero Mutual Water Company (AMWC), Templeton Community Services District (TCSD), the City of San Luis Obispo, and County Service Area 10A. These public water distribution agencies serve the urban communities of Paso Robles, Atascadero, Templeton, San Luis Obispo and Cayucos. The Initial Participants have requested 9,655 afy, which leaves a reserve capacity of 6,095 afy for an increase in these entitlements or for the inclusion of additional participants in the future. The Initial Participants have the right of first refusal for the reserve capacity. Thus, if a new participant were to request a connection to the NWP, the Initial Participants would have the contractual right to increase their allocation before the new participant is granted entitlement to water. TABLE 1 NWP WATER DELIVERY ENTITLEMENT CONTRACTS Initial Participant Allocation (AFY) City of El Paso de Robles 4,000 City of San Luis Obispo 3,380 Atascadero Mutual Water Company 2,000 Templeton Community Services District 250 County Service Area 10A 25 Subtotal 9,655 Reserve Capacity 6,095 Pipeline Total 15,750 SOURCE: San Luis Obispo County Flood Control and Water Conservation District, 2006a. 4.2 Pipeline Alignment The District has approved twelve minor refinements to the pipeline alignment described in the Final EIR. The changes are described below and illustrated in Figures 1 through 11 in Appendix A, which show both the alignments described in the Final EIR and the alignment modifications.