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A.3 FEASIBILITY OF ALTERNATIVES As described in Section A.2.3.2, various alternatives were evaluated and re-evaluated by MPWMD beginning in early 1996 to develop its Preliminary WAP and Update (MPWMD 1996a, 1998a). This section describes the results of those studies and earlier work for various alternative categories. These categories stem in part from a series of public workshops in summer and fall 1997 hosted by CPUC staff in an attempt to gain consensus from a broad sector of the community on long-term water supply solutions. Although little consensus was achieved, the workshops resulted in a problem statement, a list of the "ten promising alternative areas to study", an incomplete matrix of 75 alternative concepts, and suggestions about data needed to make a determination on the best alternative plan. Various project financing issues were also discussed. Refer to the CPUC Summary of Workshop Results (California Public Utilities Commission 1997) for more information. The following subsections are organized in accordance with the CPUC matrix. Where appropriate, the 10 alternative concepts of most interest that were identified in the CPUC workshop summary will be highlighted. These alternative concepts are:
The following subsections discuss the feasibility of seven categories of alternatives that encompass the 10 alternative concepts listed above. For each group, available data (based on previous MPWMD reports and other current sources) are summarized, including (if available) project description and operations, potential water yield (or legal supply), cost parameters, timing and implementation, environmental concerns, and other pertinent issues. Conclusions about project feasibility are made based on criteria listed in the State CEQA Guidelines and on the protocol for this effort developed by MPWMD and CPUC staff (MPWMD 1997b). In this discussion, the feasibility determination is primarily based on technology (i.e., can it be done?), legality (i.e., is it allowable?), and other compelling factors that may need to be considered. The conclusions also address major advantages and disadvantages of the alternative. If several variations of an alternative appear viable, a recommendation may be made of the most promising option(s) to combine with other alternative projects. Any alternative considered infeasible is not addressed further in this appendix. Unless otherwise noted, all projects are assumed to involve continuation of MPWMD’s long-term, comprehensive water conservation program. The feasibility and performance of various types and sizes of reservoir projects in the Carmel River Basin (and, to a limited degree, in the Fort Ord area) have been evaluated over the years, as described in Section A.2.3.1, and are not re-evaluated individually in this section. Each shares the basic concept of building a dam to block a waterway (or canyon) so that water is held back (or pumped from another source) to form a reservoir. Water is then released (or pumped) into receiving waters or directly into the Cal-Am system. For detailed background information, refer to summaries of earlier analyses in the 404(b)(1) Compliance Evaluation Final Report (MPWMD 1995f); MPWMD worksheets prepared for the February 8, 1996 alternatives workshop; and a draft matrix of alternatives prepared for the September 8, 1997 CPUC workshop. Refer to other sections of this SEIR for detailed evaluations of the CRDRP. Table A-5 summarizes information about reservoir projects that were previously designated as feasible. Project Description and Operations. Dam and reservoir projects ranging in size from a few thousand af to more than 154,000 af have been considered at several locations along the Carmel River and its tributaries and at offstream locations in the watershed, with and without pumped storage and in combination with other projects, such as desalination, new wells, or sediment removal (dredging). All dam and reservoir projects that affect the life cycle of migrating salmonid fish species, such as steelhead, must include fish passage facilities. Other typical project components are access roads, intake and outlet works, and spillways. The surface area of a reservoir requires that at least several hundred acres of relatively undisturbed land must be acquired to build the project and carry out offsite mitigation projects. For most reservoirs on the Carmel River studied by MPWMD, minimal changes to the Cal-Am distribution system would be needed because the existing system is designed to treat and convey about 70% of total production from the Carmel River Basin. Figure A-1 shows the location of reservoir sites evaluated in the EIR/IS. As described in previous EIR/IS documents, large mainstem dams and reservoirs such as the CRDRP would be operated to provide adequate instream flow in the Carmel River when feasible. Specific operating rules guide when and how much water can be stored and how much must be released to meet instream flow requirements at various locations along the river. These requirements were developed by an interagency team of fishery experts. Smaller mainstem dams or tributary dams entailed a "modified operation" that did not require extensive releases to maintain instream flow because of their limited storage capacity. Offstream and pumped storage options such as the Cañada Reservoir proposals did not entail any releases into the river, even though the storage capacity was relatively large. As noted in Section A.2.4, it is questionable whether any dam/reservoir project in the watershed would be permitted without addressing the public trust resources of the Carmel River, in light of established legal precedents, SWRCB Order WR 95-10, and recent listings of threatened species under the federal Endangered Species Act. Water Yield. Large projects such as the CRDRP, 24,000-af NLP project, and New San Clemente project would enable Cal-Am to comply with Order WR 95-10 to legalize the estimated 10,730 af/yr that is presently being diverted. Depending on operational requirements, in nearly all water-year types these projects can provide on the order of 21,000 af/yr of municipal yield as well as approximately 23,000 af/yr of instream flow releases to benefit steelhead and other river wildlife. These large projects would provide a high degree of drought protection, with infrequent rationing of no more than 20% reductions in water use. Offstream projects such as the 25,000-af Cañada Reservoir proposal (with its previously proposed operating scenario) would likely provide adequate municipal yield, but its ability to comply with the SWRCB and Endangered Species Act requirements to protect public trust resources and threatened species, respectively, is questionable. It is uncertain whether the Cañada Reservoir proposal could supply adequate municipal yield if an instream release requirement were included. Smaller reservoir projects, unless they were combined with a sizable desalination project, would not likely be able to meet the municipal and instream requirements. The adequacy of a specific reservoir project would need to be confirmed through more detailed evaluations by MPWMD and would require approval by the SWRCB. Cost Parameters. Costs for dam and reservoir projects have been estimated using a variety of water years as the basis. Stated very generally, estimated capital costs (in 1998 dollars) for reservoir projects with a storage capacity of 6,000–24,000 af would range from $87 million to $115 million. An exception is the 15,000- to 25,000-af Cañada Reservoir proposals, which would be in the $220–270 million range for capital costs because the characteristics of the underlying geology and the lack of locally available materials result in the need to import millions of tons of materials and possibly line the reservoir to prevent leaks. Operations and maintenance (O&M) costs for non–pumped-storage dam and reservoir projects are comparatively low, on the order of $3.5 million per year (in 1998 dollars); O&M costs for pumped-storage projects would be higher, in the range of $3.9–8.5 million per year. The MPWMD cost estimates for reservoir projects include costs for environmental mitigation, engineering design, and contingencies. Refer to Chapters 2 and 8 of this SEIR for a discussion of CRDRP costs and financing, respectively. Implementation Timing and Project Life. Environmental review for dam and reservoir projects is a comparatively lengthy process because of the many environmental issues involved. The CRDRP environmental review process is expected to be completed by mid-1999, and key federal and state permits have already been obtained for the NLP project. The EIR/IS for MPWMD’s long-term project evaluated many tributary and offstream reservoir projects in detail. In general, assuming environmental review is completed and permits have been obtained, an additional 4–5 years would be required before reservoir operations begin for a large project—2 years for final design and another 2–3 years for construction, depending on conditions. Smaller projects may be completed in 1–2 years less time. Given the controversial nature of reservoir projects, actual implementation could be delayed by litigation or other actions. Once a dam is constructed, its project life is estimated to be at least 100 years. Dams constructed by MPWMD include reserve capacity (unusable or "dead" storage) for infilling by sediment. For example, based on historical sedimentation rates, 100 years would pass before the active, usable storage of the CRDRP reservoir would begin to be affected by sedimentation. Environmental Issues. The most beneficial environmental effect associated with certain reservoir projects, such as the NLP project approved by the SWRCB in 1995, is the ability to restore year-round instream flow to the Carmel River in most years and enable Cal-Am to lawfully extract water while protecting the public trust resources of the river. Expert witnesses in hearings before the SWRCB emphasized that adequate instream flow was a critical component in resolving many of the environmental problems on the river. In general, the most prominent negative environmental issues associated with dam and reservoir projects include inundation impacts (e.g., loss of wildlife habitat and/or cultural resources), hydrologic effects on sediment transport and channel characteristics, effects on threatened or endangered species, and construction-related effects on the community (e.g., traffic, noise, air quality). Depending on the location of the project, long-term changes in views may result for nearby landowners and visitors. Reservoir projects also entail substantial investment of funds and resources for long-term mitigation programs. Other Issues. Reservoir projects are controversial on the Monterey Peninsula, with deeply entrenched positions held by various interest groups and individuals. The potential water yield from large reservoir projects elicits divergent viewpoints on the issue of providing water for growth, an issue that has polarized residents of the Monterey Peninsula for years. With very few exceptions, local landowners have strenuously opposed location of a new or enlarged reservoir on or near their property at several potential sites in the watershed. A 24,000-af reservoir at the NLP site has been shown to be feasible, in that key state and federal permits have been issued for the project. As noted in Section A.2.4, various offstream and tributary reservoirs may be technically feasible, but the substantially higher cost (such as for the Cañada Reservoir proposal), with relatively low yield and questionable ability to provide instream flows to compensate for the loss of inundated habitat, result in questionable overall feasibility. Advantages of reservoir projects include collection and conveyance of water by means of gravity flow, resulting in relatively low O&M costs for non–pumped-storage projects; a nominal effect on the Cal-Am distribution system; a long project life with little need to replace facilities; efficient use of seasonal rainfall; increased water system flexibility (conjunctive use); and the ability to improve streamflow conditions. Disadvantages include relatively high capital costs because of the massive structures and large amount of land area needed; relatively long design and construction periods; impaired performance in extended droughts (i.e., droughts lasting three or more consecutive years); the need to mitigate for a wide variety of environmental impacts; and high potential for public controversy. Desalination refers to the facilities and processes (such as reverse osmosis or distillation) used to separate fresh, potable water from a salty source (such as seawater or brackish water). MPWMD and other local agencies have evaluated a variety of desalination project methods, sizes, and locations from Carmel to Moss Landing. For more information, refer to summaries of earlier analyses in the 1992 Final EIR for the Near-Term Desalination Project (MPWMD 1992); the 1995 404(b)(1) Compliance Evaluation Final Report (MPWMD 1995f); MPWMD worksheets prepared for the February 8, 1996 Alternatives Workshop; the 1996 desalination feasibility study update (Parsons Engineering Science 1997); and a draft matrix of alternatives prepared for the September 8, 1997 CPUC workshop. Table A-6 provides a summary of information gleaned from these studies. Project Description and Operations. MPWMD first evaluated small (as much as 3- to 4-MGD) projects at various locations as part of its Near-Term Water Supply Program, culminating in a public vote on construction of a 3-MGD seawater desalination project in Sand City in June 1993 (voters rejected that project). When the NLP project was not authorized in November 1995, MPWMD retained Parsons Engineering Science in 1996 to update 1993 information; determine the largest capacity project that could be built at the Sand City site; determine the feasibility and preliminary costs of much larger desalination options (up to a 14-MGD project near Marina or at Moss Landing Power Plant) that could serve as stand-alone, long-term water supply projects or cornerstones of combined water resource plans; and identify critical environmental and permitting issues. These site locations are shown in Figure A-2. The recommended method for local seawater desalination projects is reverse osmosis, in which seawater is pushed through a membrane under high pressure to separate fresh water molecules from the salt. For projects associated with power plants, a distillation method is suggested (fresh water is separated from the salt by boiling it, then cooling the steam). Regardless of the method used, the basic components of a desalination project include facilities to collect, transport, and pretreat (if needed) seawater or brackish water to the desalination site; desalt the water; treat, store, and convey the drinking water to the Cal-Am distribution system; and treat the concentrated brine and convey it back to the ocean (or other receptor) in an environmentally appropriate way. Desalination projects in Moss Landing or near Marina would entail the construction and use of lengthy pipelines, pump stations, and other conveyance facilities. Desalination projects require a relatively small amount of space; can be housed easily in industrial areas; and lend themselves to modular, phased increases in production over time. A 1997 draft hydraulic analysis performed by Cal-Am (American Water Works Service Company 1997) describes and provides cost estimates for the additional and expanded storage and distribution facilities that must be built to receive desalinated water (or water from any other source) from the northern end of the Cal-Am system. Presently, the northern distribution system (Seaside area) is not designed to be the primary entry point into the system for substantial quantities of new source water. Reconfiguration of the Cal-Am system, including new facilities, would be necessary if large quantities of water were to be received from areas other than Carmel Valley. Desalination plants are relatively flexible and can be operated in a variety of ways. Three basic operating scenarios exist:
Water Yield. The operating scenario affects the annual water yield from a desalination project, which is usually described in terms of millions of gallons per day (MGD) of drinking water that can be produced at full capacity. Because of factors such as maintenance requirements and efficiency considerations, this level of production cannot be maintained every day, year round. Thus, a typical estimate for annual production with constant use (Scenario 1) is 90% of the daily MGD rating; seasonal operation (Scenario 2) results in about 60% of the daily MGD rating. For example, 3 MGD equates to about 3,360 af/yr. Actual production for a 3-MGD plant under constant use would be about 3,000 af/yr. Seasonal operation would result in production of about 2,000 af/yr of water. As shown in Table A-6, annual production from the conceptual desalination projects studied range from 2,000 af/yr to 14,000 af/yr. These amounts would be applied to unlawful diversions from the Carmel River Basin and help Cal-Am comply with SWRCB Order WR 95-10. (Note: The water quantities described in this analysis are finished water. Nearly 2 gallons of raw seawater must be collected to produce 1 gallon of finished drinking water. Thus, desalination facilities must be designed to process approximately double the quantities of water described above.) Sources of less costly, brackish water supply are limited; therefore, MPWMD has focused on seawater desalination because an endless supply of seawater is available that is independent of drought. The major constraints on the annual production capacity of local desalination projects are the physical and institutional limits placed on intake and brine discharge facilities to avoid potential impacts on the Monterey Bay National Marine Sanctuary. As described in previous reports, new ocean-based intake and outfall pipelines (or expanded use of existing pipelines) may be prohibited or restricted by the National Oceanic and Atmospheric Administration (NOAA), which manages the sanctuary. At Sand City or nearby locations, intake and discharge would involve the use of special injection/ejection wells (Ranney collectors) through beach sands. For the Marina site, Ranney collectors would be used for intake and the existing treated wastewater outfall pipeline operated by the MRWPCA would be used for discharged brine. The Moss Landing Power Plant site would use existing pipelines for intake and discharge. The study by Parsons Engineering Science concluded that a 3-MGD project at the Sand City site is feasible and that a project as large as 5–6 MGD may be possible at that site. Various environmental concerns would need to be resolved by NOAA and other agencies before a 4- to 6-MGD desalination plant could be pursued. That study also concluded that the feasibility of a larger desalination project (7–14 MGD) near Marina or at Moss Landing is questionable because of environmental factors (described below), constraints of the Cal-Am distribution system (described above), adverse effects on treated wastewater dispersion if the MRWPCA outfall were used, and availability of a secure seawater source at the Moss Landing Power Plant since Pacific Gas and Electric Company (PG&E) recently sold the facility. Other concerns include limited availability of sites for large numbers of Ranney collectors because of competition among agencies for desalination sites within and outside MPWMD boundaries (e.g., Sand City and FORA contemplate use of desalination projects to provide water for planned development projects). Although conceptual single-site projects of as much as 14 MGD are addressed in this appendix, the feasibility of projects with capacity of more than 6 MGD have yet to be demonstrated. Two or more smaller plants may need to be built at different locations to produce water yields greater than 6,000 af/yr. Cost and operational data from a new 0.3-MGD desalination project completed in 1997 by the Marina Coast Water District may help shed light on this issue. Cost Parameters. The desalination method, plant location, and type of operation greatly affect the cost of a particular project because desalination projects are energy intensive. For the 3-MGD plant at Sand City, the capital cost is estimated at $29.2 million (in 1998 dollars, based on the Parsons study). Also, based on a separate hydraulic study by American Water Works Service Company, Cal-Am’s parent company, an additional $9.0–13.4 million in capital facilities would be needed to receive and convey the desalinated water. Thus, the total initial capital cost would be $38.2–42.6 million. Based on the Parsons study, O&M costs (in 1998 dollars) are estimated to be $2.1 million and $2.8 million per year for seasonal (Scenario 2) and full-time (Scenario 1) use, respectively. These figures are low as they do not include costs to implement environmental mitigations or O&M costs associated with Cal-Am system improvements. Similarly, for a 6-MGD plant at Sand City, the project’s initial capital costs would be $53.2 million for construction. According to the hydraulic study, Cal-Am capital costs would be $12.7–17.9 million, resulting in a total capital cost of $65.9–71.1 million. Based on the Parsons Engineering Science study, O&M costs would be $3.9 million per year and $5.4 million per year for seasonal and full-time operations, respectively. These figures are low because they do not include Cal-Am O&M costs or costs to implement required environmental mitigation. Refer to Table A-7 for a detailed cost summary. Parsons developed cost estimates for desalination plants ranging in size from 7 MGD to 14 MGD at the Marina and Moss Landing sites, assuming they are found to be feasible. Initial capital costs ranged from $72.0 million to $171.3 million. An additional $13.4–19.4 million in capital costs would be needed for improvements to enable the Cal-Am system to receive water from the north end of the water system. Thus, total capital costs would range from $84 million to $190.7 million. Based on the Parsons Engineering Science study, O&M costs would be $4.6–9.3 million per year for seasonal use for plants with capacity of 7–14 MGD and $6.4–12.9 million per year for full-time use. These figures are low because they do not include Cal-Am O&M costs or costs to implement required environmental mitigation. These cost estimates are preliminary and subject to change; refinement would depend on additional investigations to determine project feasibility and the ability to adequately address environmental issues. The capital cost estimates cited above are initial capital costs. A seawater desalination plant is expected to have a life of about 20–25 years, at which time major capital facilities must be replaced. (Membrane replacement occurs in approximately 5-year intervals and is included in O&M costs.) The estimated replacement costs of a desalination plant are factored into present-worth comparisons with other projects that have a longer project life (e.g., 50–100 years). Because desalination typically costs more per af than traditional sources of supply, the desalination industry is striving to implement improvements that reduce costs. The 1997 Parsons Engineering Science report and industry trade journals (e.g., Desalination and Water Reuse Quarterly [Leitner 1998]) indicate that many new technological advances, such as carbon aerogel filters, are still in the research and development (R&D) stage and have not been demonstrated to be viable in commercial or municipal settings. Potential breakthroughs in cost per af have recently been reported in the Tampa Bay area of Florida in proposals for large (20- to 50-MGD) distillation plants associated with power plants. These costs would not be directly applicable to Monterey Peninsula projects, however, because of the higher cost of energy in coastal California, the lower salinity of the source water at the proposed Tampa Bay sites, the larger size of the Florida projects, and environmental concerns that were not addressed in the Tampa Bay proposals. Implementation Timing and Project Life. The environmental review and permitting process for large desalination projects is expected to be relatively lengthy (1–2 years) because of the sensitive nature of the marine sanctuary, the presence of listed endangered species on affected coastal dunes, potential wetland impacts at certain sites, air quality concerns associated with energy use, and the fact that few large desalination projects have been constructed and operated successfully in coastal California. Once environmental review is completed and permits have been obtained, another 1–3 years would be needed for final design and construction, depending on the project size and site location. Once constructed, the project would have a life of 20–25 years, after which major capital facilities must be replaced. The O&M costs for reverse osmosis projects include budget to replace membranes every 5 years. Environmental Issues. The major environmental benefit of a desalination project is its ability to produce a substantial quantity of water that could replace diversions from the Carmel River Basin, thereby helping to reduce the adverse effects of municipal water use on the river. Only the largest project studied (a 14-MGD project) would have an effect on streamflow similar to that of the CRDRP (Fuerst and Bell pers. comm.). The building footprint of a desalination project covers a relatively small area and would not inundate substantial acreage of wildlife habitat; construction impacts would be relatively modest compared to those of a dam and reservoir project. The environmental impacts of a desalination project depend on plant size, the desalination method used, and the proposed plant location. The following major issues must be considered:
Environmental monitoring information from a new 0.3-MGD desalination project completed in 1997 by the Marina Coast Water District may address some of these concerns. Other Issues. As water-related issues become more critically important regionally, nationally, and internationally, public and political interest in the concept of desalination continues to be high. However, on a project-specific level, desalination is often rejected in favor of other sources of supply that are less expensive and less energy-intensive, if such sources are available. As populations increase and existing water resources become depleted, government funding to support innovative desalination technologies can be expected to increase, and broader applications of desalination will probably be developed to address a variety of resource management issues. A local example is the proposed use of a small desalination project (less than 1 MGD) to serve the following two purposes:
Desalination plants of various sizes have been shown to be technically feasible throughout the world, although questions exist about the physical and institutional feasibility of large plants (larger than 6 MGD) in certain locations on the Monterey Peninsula because of potential limitations on the locations of intake and outfall facilities. Capital costs of larger plants are comparable to those of other large-scale alternatives, such as dams, but O&M costs are much higher. Advantages of desalination include a relatively short construction period once permits have been obtained; relative ease to add phased modules; a consistent, "drought-proof" source of supply (the ocean); various operational options; and lack of inundation effects. Disadvantages include substantial capital costs for facilities that must be incurred every 20–25 years; high operating costs and energy use; the need for regular replacement of major capital components required as a result of corrosion by seawater and other chemicals; and potential adverse environmental impacts on marine life, endangered coastal dune species, and wetlands. A.3.3 DREDGING OF EXISTING RESERVOIRS Dredging refers to the removal, dewatering, conveyance, and disposal of accumulated sediment from existing reservoirs to regain lost capacity (or maintain existing capacity). Cal-Am, MPWMD, and the City of Santa Barbara have evaluated the feasibility and cost effectiveness of various dredging projects. For more information, refer to summaries of earlier analyses in the 1994 NLP Final EIR (MPWMD 1994a); MPWMD worksheets prepared for the February 8, 1996 Alternatives Workshop; the San Clemente Reservoir Dredging Feasibility Study prepared for Cal-Am (Moffatt & Nichol Engineers 1996); a draft matrix of alternatives prepared for the September 8, 1997 CPUC workshop; and an MPWMD preliminary evaluation of dredging yield dated September 29, 1997 (MPWMD 1997c). Table A-8 provides a summary of information presented in these studies. Project Description and Operations. The two dredging options for the Carmel River system are sediment removal from the existing San Clemente and Los Padres Reservoirs, which are both owned and operated by Cal-Am. San Clemente Reservoir was completed in 1921 with an original capacity of 1,425 af at the spillway elevation of 525 feet (flashboards are assumed to be lowered permanently); existing (1998) capacity is estimated by Cal-Am to be 147 af. Los Padres Reservoir was completed in 1949 with an original capacity of 3,033 af; current capacity is estimated at 2,179 af. The estimated capacity lost to sedimentation from upstream sources (both natural and as a result of human intervention) is 1,278 af for San Clemente Reservoir and 854 af for Los Padres Reservoir, for a total lost capacity of 2,132 af. An important new development (as of August 1998) is the fact that dredging San Clemente Reservoir presently does not appear to be an option, based on discussions to date by an interagency group of engineering and fishery experts convened by the DWR and Cal-Am to address the existing and long-term sedimentation problems in San Clemente Reservoir. After weighing the pros and cons of several sedimentation options (including dredging the reservoir), the group favors the concept of maintaining a long-term average of about 200 af of storage in the reservoir by building sluice gates into the dam. Operated in accordance with a detailed plan to be developed by the interagency group, the sluice gates would be opened when the riverflow through the reservoir is suitable to carry sediment downstream. These gates would be incorporated into seismic retrofit designs currently being prepared at the direction of DSOD. A separate EIR on the San Clemente Dam Seismic Retrofit Project is being prepared by DWR and is scheduled for release in fall 1998; the analysis in that document will be used to update this discussion in the Final SEIR. Water Yield. Two concepts are discussed in the following paragraphs: dredging only Los Padres Reservoir, and dredging both Los Padres and San Clemente Reservoirs. The feasibility of dredging both reservoirs is questionable in light of the current (but not formally confirmed) plans to maintain approximately 200 af of storage and build sluice gates at San Clemente Dam. Preliminary analyses conducted by MPWMD in September 1997 indicate that neither dredging concept would substantially increase Cal-Am system reliable water yield or drought protection because of the small amounts of water storage involved. In general, the increase in the amount of storage is typically much greater than the reliable, long-term yield gained. However, from a water rights perspective, reclaiming lost reservoir storage capacity could enable Cal-Am to legally store and redivert more water each year. Specifically, by dredging Los Padres Reservoir to its original capacity, Cal-Am’s licensed right at that site could be increased from the current 2,179 af to 3,033 af annually, an increase of 854 af. If both Los Padres and San Clemente Reservoirs were dredged, the potential increase in legal diversions to storage could total as much as 2,132 af. Cal-Am would have to apply for rights to divert San Clemente Dam water to storage during the high-flow winter period—when it is presently available for appropriation—for release and rediversion during the low-flow period. These changes would need to be reviewed and approved by the SWRCB. As noted above, dredging of San Clemente Reservoir does not appear to be feasible. The Moffatt & Nichol report evaluated use of slurry pipelines (as an alternative to trucks) to convey dredged materials to help reduce traffic impacts; however, this method would require 850–1,200 af/year to keep the dredged material suspended in the pipelines. This is a substantial amount of water and would offset any capacity gained by dredging; for that reason, this method is not recommended. Cost Parameters. As described in the Moffatt & Nichol 1996 evaluation of San Clemente Reservoir dredging options, the selected dredging conveyance method and disposal location have a substantial effect on costs. Estimated total costs to dredge and dispose of 620 af (1 million cubic yards [CY]) would range from $8 to $29 million; for 1,240 af (2 million CY), total capital costs would range from $25 to $48 million. Depending on the disposal site, estimated costs would range from about $8 per CY ($13,000 per af) to more than $29 per CY ($47,000 per af) for 1 million CY, and from about $12 to $24 per CY for 2 million CY. It is notable that these estimates do not include mitigation costs, which could be substantial. To maintain the water rights described above, a maintenance dredging program would be required to remove the estimated average of 17 af of sediment deposited each year. The 1996 Moffatt & Nichol report did not include a description of or a cost estimate for such a program but noted that the dredged material from San Clemente Dam (e.g., sorted sand, gravel, and cobble) would have a market value. The report suggested that entering into a partnership with construction or mining companies could help offset the anticipated costs but did not incorporate potential revenue into the cost estimates because of the questionable environmental feasibility of many of the options. A similar detailed study has not been performed for dredging Los Padres Dam, which would entail removal of about 1.38 million CY (854 af) of sediment. Costs are assumed to be higher because of the longer distance to disposal sites. Assuming a range of $8–29 per CY (similar to San Clemente Dam costs), the estimated capital cost to completely regain capacity would be about $11–40 million (at 1996 price levels). Again, these estimates do not consider mitigation costs or the potential market value of the dredged and sorted materials. Implementation Timing and Project Life. The environmental review and permitting process for a major dredging project would take at least 1-3 years to complete, given that federal (Clean Water Act Section 401 and 404, Endangered Species Act Section 7) and state (streambed alteration, regional water quality control board [RWQCB] discharge) permits would be required and substantial fishery, wetland, and water quality issues would be associated with this alternative. According to the Moffatt & Nichol report, the actual dredging and disposal of material from San Clemente Reservoir would take 1–15 years for 1 million CY (620 af) and 5–30 years for 2 million CY (1,240 af). The number of years needed would be greatly affected by the disposal option and conveyance rate used (variations of slurry pipeline, truck haul-off, barge haul-off) and weather-related impacts. Variations that feature truck haul-off would take at least 10–15 years. These periods are assumed to be similar for the same process at Los Padres Reservoir. In theory, if dredging of San Clemente Reservoir were feasible, an estimated 10–30 years would be needed to dredge both reservoirs. Previous estimates by MPWMD consultants indicated that each reservoir receives an average of about 20 af/yr of new sediment. This is equivalent to about 32,300 CY of additional sediment that must be removed each year. Thus, the timing estimates for removal described above are low by at least 3%. Additional time may be needed because these estimates do not consider "bulking" (expansion) of material, which occurs when sediment is handled and moved. Environmental Issues. The primary environmental benefit of dredging is that additional reservoir capacity can be obtained without inundating new habitat. The major potential adverse biological impact is the smothering of fishery and other aquatic wildlife habitat downstream of the reservoirs by uncontrolled releases of fine sediment during the dredging process. This possibility is of great concern to federal and state fishery experts and is one reason why the use of controlled sluice gates rather than dredging is presently preferred at San Clemente Dam. Of significant local concern is the substantial traffic impact on local roads as a result of the thousands of truck trips that would be involved over many years. For example, 1 million CY (620 af) of sediment would equate to 50,000 and 83,000 truckloads at the assumed loading rates of 20 CY and 12 CY per load, respectively. Disposal of 2 million CY would require 100,000–166,000 truckloads. The number of one-way truck trips would be double this amount (i.e., 200,000–332,000) to first carry the materials to the disposal site, then return (empty) to the processing site in Carmel Valley. Assuming an off-haul rate of 175,000 CY per year (the average of the 150,000–200,000 CY per year cited in the Moffatt & Nichol report), this would be nearly 29,200 truck trips per year [(175,000 CY per year ¸ 12 CY per load) x 2 one-way trips], which equates to 80 truck trips per day, every day of the year (actual daily trips would be higher because no trucking would take place on weekends and holidays), or at least 10 truck trips per hour for an 8-hour day. At 175,000 CY per year, a total of 5.7 years would be required to remove 1 million CY (620 af) and 11.4 years to remove 2 million CY (1,240 af). Given the already inadequate level of service on Carmel Valley Road, Highway 1, and other area roadways, the traffic impacts that would be associated with dredging seriously impair the viability of this alternative. San Clemente Drive would require ongoing maintenance and repair because of the heavy truck traffic. The estimates presented above may be 10–15% low because they do not account for the bulking (expansion) factor associated with handling and processing the dredged material. In-reservoir estimates of volume are based on measurements of compacted sediment; a 10–15% increase in volume is expected once the material is loaded into a truck. Other Issues. The experience of the City of Santa Barbara, in a 3-year dredging project to regain some of the lost storage in Gibraltar Reservoir (City of Santa Barbara 1986), and other experts indicates that dredging to regain lost reservoir storage "is an extremely expensive, if not impossible" undertaking (Annandale pers. comm.). High cost and environmental concerns resulted in a decision by Santa Barbara to abandon dredging as a solution to developing additional water yield for the city. Internationally, water managers and engineers are now designing sediment management programs to maintain new or existing reservoir storage, rather than attempting to regain storage lost to sedimentation. The concept of dredging is appealing in that lost reservoir storage could be regained and certain lost water rights could be reclaimed. The Moffatt & Nichol study at San Clemente Dam determined that removal of sediment from the reservoir is technically feasible, but serious questions exist with regard to the economic and regulatory feasibility of conveyance and disposal. Key concerns are the extremely high overall cost (and cost per af), need for large quantities of water to implement pipeline slurry options, substantial traffic impacts associated with trucking, and environmental impacts on downstream fishery and aquatic wildlife habitat. Because of these concerns, an interagency oversight group has selected a nondredging method to facilitate sediment management and maintain about 200 af of storage at San Clemente Dam. Thus, for the purposes of this appendix, subsequent evaluations of alternative plans that include dredging assume that dredging can be performed only at the Los Padres Dam site; dredging at San Clemente Dam is not presently considered a reasonably foreseeable option. A.3.4 GROUNDWATER DEVELOPMENT, INCLUDING INJECTION AND RECOVERY Groundwater development refers to production of additional water from alluvial (river-based) aquifers, groundwater basins, or upland sources such as fractures in mountain bedrock that may yield water. Groundwater development also refers to means of increasing groundwater storage or availability by methods such as injection and recovery, which are described below. Groundwater development typically relies on the creation and use of large production wells and other facilities (e.g., pipelines, pump stations, treatment plants, and storage tanks) that are needed to convey water of acceptable quality into the Cal-Am system. MPWMD, Cal-Am, and other private entities have evaluated (or plan to evaluate) the feasibility and cost-effectiveness of various groundwater development projects. For more information, refer to summaries of earlier analyses in the 1994 NLP Final EIR (MPWMD 1994a); MPWMD worksheets prepared for the February 8, 1996 Alternatives Workshop; and a draft matrix of alternatives prepared for the September 8, 1997 CPUC workshop. Table A-9 provides a summary of information on groundwater development provided in these studies. A.3.4.1 Groundwater Development Concepts
Groundwater development has been or is currently being explored in the following areas:
The following paragraphs describe each concept and provide a determination on whether each is a reasonably foreseeable, feasible source of additional lawful water yield for the Cal-Am system. A more detailed discussion is then provided for those concepts determined to be feasible. Carmel Valley Alluvial Aquifer Sources. The Carmel Valley alluvial aquifer extends for approximately 18 miles near San Clemente Dam to the Carmel River Lagoon, as shown in Figure A-3. Its maximum thickness is about 200 feet, with a typical thickness of 50–100 feet. Total storage is estimated at 48,000 af; usable storage is estimated at 28,500 af. The basin is highly permeable; it is recharged rapidly by winter streamflow but can be quickly depleted during extended dry periods. Substantial quantities of water (more than 1,000 gallons per minute) can be extracted with relative ease by wells in the alluvium. Cal-Am and numerous other water consumers extract water from more than 200 wells in the Carmel Valley alluvial aquifer. As described in Order WR 95-10; Decision 1632; and letters dated September 29, 1997, and July 14, 1998 (Pettit and Anton pers. comms.), obtaining additional water yield for the Cal-Am system from alluvial wells is not legally possible. A formal regulatory process and approval by the SWRCB are required before additional yield can be legally taken by any party with wells within SWRCB jurisdiction. In accordance with SWRCB Order WR 98-04, Cal-Am plans to explore the feasibility of drilling wells in the Lower Carmel Valley on donated land and replumbing its distribution system in the Upper Carmel Valley. These two activities would help reduce the environmental impacts of water extraction by changing the timing and location of extractions from the well network, but extractions would remain within the existing annual production goal set by the SWRCB. These activities would not result in an increase in lawful water yield because they would continue to divert water from subsurface flows of the Carmel River, which are controlled by the SWRCB. Based on studies conducted by MPWMD, the amount of water that can be pumped from these wells is limited by potential adverse impacts on the Carmel River Lagoon. Although construction of new wells in the alluvium is technically feasible and may have environmental benefits related to riverflow upstream, this alternative is not considered a reasonably foreseeable, feasible source of new, lawful water supply because water diversions are limited under the constraints imposed by the SWRCB. Section A.2.3.2 provides background information on these SWRCB actions. Carmel Valley Upland Sources. Extensive evaluations of potential groundwater production in upland (nonalluvial) areas of Carmel Valley have been conducted in association with environmental review of proposed subdivision projects such as the Santa Lucia Preserve (also called Rancho San Carlos) (Monterey County 1995). These studies have shown that the potential for reliable, long-term production from wells in upland locations is very limited and, in most cases, the production potential (1–50 gallons per minute) is 1–3 orders of magnitude (10–100 times) lower than that of a typical Cal-Am well in the alluvial aquifer. Because of the very low production capability of upland formations, an extensive network of wells would be needed to produce a nominal amount of water. For example, the Rancho San Carlos studies indicate that 95–139 wells may need to be operated over the 20,000-acre property to reliably produce 400 af annually. For a public (municipal) application, the economic feasibility of such a network is questionable, based on the estimated capital cost of approximately $50,000 per well. Assuming that 120 wells are needed to produce 400 af/yr of reliable supply, the wells alone would cost $6.0 million, and the cost per af would be $15,000. These cost estimates are considered very low because they do not include electrical power to operate the wells and development of an integrated water treatment and conveyance system. (Section A.3.6.1 provides more information on potential water importation and marketing from Rancho San Carlos.) Based on the Rancho San Carlos data, the extensive acreage needed to produce meaningful quantities of water would not be available for well development by Cal-Am. Substantial acreage in Carmel Valley is preserved as either parkland or private open space (rangeland). Other lands are proposed for subdivisions by the existing landowners. As explained in Section A.3.6.1, water marketing possibilities also appear to be extremely limited. For these reasons, this alternative is not considered a reasonably foreseeable, feasible alternative that would yield a new, lawful supply for the Cal-Am system. Carmel Valley Deep Fractured Bedrock. A private firm (SAMDA) has conducted reconnaissance-level investigations of groundwater supply from deep bedrock in the Monterey County area using satellite imagery and remote sensing techniques, and the results indicate that the potential exists to develop economically significant quantities (at least 500 af) of groundwater from these sources. SAMDA first approached MPWMD in 1993 to discuss MPWMD’s interest in entering into an agreement to purchase water from yet-to-be-developed wells in the Big Sur coastal region south of the district’s boundaries. Because of concerns about potential environmental impacts on nearby springs, creeks, and wells associated with extracting water at the locations proposed by SAMDA, and because of noncompliance with the Big Sur Coastal Land Use Plan, which discourages interbasin transfers of water, MPWMD in 1994 rescinded its initial agreements with SAMDA. In early 1996, SAMDA identified additional prospective drilling sites in the Cachagua Valley, an area partially outside MPWMD boundaries and under the jurisdiction of Monterey County. This proposal was determined to be in conflict with policies of the Cachagua Area Plan and would require amendment of that plan before Monterey County would approve water exportation from this area. Because of these identified constraints, SAMDA indicated in 1997 that it would focus on potential exploration sites within MPWMD boundaries and outside the boundaries of either the Big Sur Coastal or Cachagua Area Land Use Plan. More recently, SAMDA has proposed to consider exploration drilling on the south side of Carmel Valley, on a 400-acre property known as Twin Cities Ranch (formerly Holt Ranch), west of Robinson Canyon and north of Rancho San Carlos. Given that Twin Cities Ranch is in a similar hydrogeologic setting as Rancho San Carlos (described above), the potential for this property to produce the minimum quantity of 500 af/yr from an economically and environmentally manageable number of wells is questionable. In November 1997, the MPWMD Board of Directors voted not to enter into an agreement with SAMDA because of the technical, regulatory, and economic concerns noted above. Instead, the board suggested that SAMDA contact Cal-Am, which could purchase and distribute any water that is developed by SAMDA. Cal-Am and SAMDA have signed an initial agreement, but no testing program has been undertaken (although completion of testing is slated for no later than May 2000). For all of these reasons, this alternative is not considered a reasonably foreseeable, feasible alternative that would yield a new, lawful supply for the Cal-Am system. Seaside Basin. The Seaside Basin encompasses about 24 square miles underlying most of the City of Seaside and a portion of the former Fort Ord Military Reservation (Figure A-4). Geologically, it is more complex than the Carmel River Basin and has been divided into several subbasins and subareas, as well as two layered, water-bearing strata. Its total thickness extends to more than 900 feet in places. In contrast to the Carmel River Basin, the Seaside Basin area is characterized by a large volume of total storage (an estimated 550,000 af) but a relatively small volume of usable storage (approximately 7,500 af) that is above sea level in the coastal areas of the basin, where the municipal supply wells are located. The basin is characterized by low permeability and low recharge rates compared to the "flashy" (more quickly responsive) alluvial aquifer in the Carmel Valley. Thus, the basin is presently viewed more as a dry-period supply source to help alleviate physical impacts of water diversions and SWRCB regulatory constraints on water use from the Carmel River Basin. Additional groundwater development, if feasible, could increase community reliance on the basin year round. Seaside Basin Northern Inland Subarea. The Seaside Basin Northern Inland Subarea underlies a substantial portion of the former Fort Ord Military Reservation. MPWMD-sponsored groundwater exploration investigations in 1985–1987 concluded that a maximum of 1,300 af/yr might be extracted from the area, but the poor-quality water would require extensive treatment (Converse Consultants 1985; Staal, Gardner & Dunne 1987). Capital costs in 1985 were estimated at $4.5–5.5 million. These facts, along with safety and water quality concerns associated with unexploded ordnance in the Fort Ord area, impacts on endangered species, and other issues, resulted in this alternative being dismissed from consideration in 1988. Also, at the time these studies were conducted, more than 6,000 af/yr of water from the basin were being extracted under federal water rights to supply the U.S. Army at Fort Ord, which has since closed; this water is now slated for use in accordance with the Fort Ord Reuse Plan (Fort Ord Reuse Authority 1997). The closure of Fort Ord and development of the Fort Ord Reuse Plan may preclude development of wellfields in certain areas. If groundwater is developed in this area, MPWMD assumes that it will be used for onsite or adjacent uses by development approved by FORA. For these reasons, this alternative is not considered a reasonably foreseeable, feasible alternative that would yield a new, lawful supply for the Cal-Am system. Section A.3.6.1 contains a discussion of the water marketing potential from the Fort Ord area. Seaside Coastal Subareas. Groundwater from the Northern and Southern Seaside Coastal Subbasins is currently being extracted by Cal-Am, the City of Seaside, and individual landowners. The last major municipal well developed in the area by Cal-Am was the Paralta well in 1993, for which the MPWMD set an annual average production volume of 1,000 af/yr. At that time, MPWMD hoped that an additional 1,000 af/yr could be safely extracted with the well, but such an increase would depend on the results of multiple-year monitoring of nearby water levels. In December 1997, MPWMD consultants presented a hydrogeologic update report (Fugro West 1997a) to the MPWMD Board of Directors that the following determinations:
One of the key recommendations of the report was the need to redistribute groundwater pumping within the coastal subareas to manage the basin more effectively while remaining within its long-term yield. Accordingly, MPWMD and Cal-Am, the principal water producer in the basin, have developed and implemented revised basin operation and management scenarios in 1998. An important result of the Fugro West hydrogeologic report is the determination that production from the Paralta well should not be increased to serve Cal-Am customers. Because of the limited availability of Cal-Am water for redevelopment projects in Sand City, landowners are considering reactivating wells formerly used for sand mining and other industrial applications to serve resort, commercial, and residential projects. Based on the outcome of current water rights and other legal claims in the coastal area, Cal-Am may be required to further reduce overall production to accommodate non-Cal-Am water users without adding new facilities such as the injection and recovery wells described below. For these reasons, this alternative is not considered a reasonably foreseeable, feasible alternative that would yield a new, lawful supply for the Cal-Am system. Injection and Recovery in the Seaside Coastal Subareas. The concept of injection and recovery involves diverting treated excess winter flows from the Carmel River (as allowed by the SWRCB) through existing (or expanded) Cal-Am facilities and injecting the water into the Seaside Coastal Subareas for later recovery. If the injection is successful, then additional yield could be produced from the basin with existing or new wells. Preliminary studies by consultants in 1996 (Fugro West 1997c) indicated that this alternative is promising and should be tested further through construction of a pilot test facility. Based on this recommendation, MPWMD obtained permits for a test project in 1997; constructed a test injection well in early 1998; and completed initial testing through May 31, 1998, when the temporary water rights permit expired. The injection/recovery project is described further in Section A.3.4.2 because of the reasonably foreseeable possibility that additional lawful Cal-Am production could result from this project. Other Concepts. Other concepts that have been considered, but not pursued, include the following:
For the above reasons, these four alternative concepts are not considered reasonably foreseeable, feasible alternatives that would yield a new, lawful supply for the Cal-Am system. A.3.4.2 Seaside Basin Injection/Recovery Project Project Description and Operations. As noted above, the Seaside Basin injection/recovery project entails diversion of excess Carmel River winter flow using the Cal-Am distribution system; the water would be first treated, then injected into the Seaside Coastal Subareas by means of specialized injection/recovery wells with technology that has been perfected in recent years. (In theory, other sources such as imported water could be used if the imported and native sources are demonstrated to be chemically compatible. Evaluations have shown that Carmel River water is chemically compatible with water from the Seaside Coastal Subareas.) As much as about 7,000 af of storage capacity may be available in the Seaside Coastal Subareas at present. The goal would be to replenish aquifer storage as much as is feasible in winter, based on Carmel River streamflow conditions, and then extract groundwater at a high rate in the dry season. Also, a fuller basin in the Seaside area could provide more drought storage reserve to be used during extended dry periods. Project operations would be guided by diversion conditions imposed by the SWRCB after formal hearings were conducted on an application to divert unappropriated waters during the winter season. Based on previous SWRCB determinations, river diversions are assumed to be permitted only from December through May, and only when streamflow exceeds specified triggers during each of those months, similar to the requirements stipulated in SWRCB Decision 1632. Water Yield. In late 1996, MPWMD retained a consultant to analyze the potential for an injection/recovery project in the Seaside Basin, including facility requirements, operations, and projected yield (Fugro West 1997c). Subsequently, MPWMD drilled a pilot injection well and conducted an initial injection test in May 1998. Based on results of the pilot testing program, analysis by MPWMD staff using the CVSIM computer simulation model determined an average annual injection potential of 1,840–2,620 af/yr, as shown in Table A-10. The low end of this range assumes installation of new injection/recovery wells but minimal changes to the Cal-Am distribution and treatment system. The high end of the range anticipates that major improvements would be made to the Cal-Am system, including pipeline enlargements, expansion of a major pump station, and expansion of the Carmel Valley Filter Plant. As shown in Table A-10, the long-term sustainable yield from the basin is estimated to increase by 1,700–2,080 af/yr on average. The availability of water for injection in a wet year (such as water year 1983) could be as high as 5,500 af. Little or no injection would be possible in dry years. The values shown in Table A-10 assume that an injection/recovery project would be added to the existing Cal-Am system as a stand-alone project. If injection/recovery is combined with other water supply project alternatives, these values would change. These estimates are considered preliminary and have not been refined by rigorous field testing. Initial testing by MPWMD in spring 1998 determined that the sustainable injection capacity of the new pilot well is at least 472 gallons per minute (2.1 af per day) but may be increased to 800 gallons per minute (3.5 af per day) subject to the availability of additional booster pumping capacity, which would require modification of the Cal-Am water transmission system (Fugro West 1998). Full use of available excess flows from the Carmel River would require development of about 4,700 gallons per minute (20.8 af per day) of injection capacity, indicating that six or more similarly constructed injection wells may be needed to achieve the yields discussed above. However, a well with a different design than the pilot well (e.g., a well that uses both of the basin’s principal aquifer zones) could perform better at either the present or another test site. MPWMD will continue to evaluate the feasibility and potential performance of this alternative, with additional field testing and analysis planned for the 1999 recharge season. Cost Parameters. As shown in Table A-10, capital costs for the needed injection and collection facilities, based on information developed by MPWMD consultants, range from $8.1 million to $15.9 million. These estimates do not include costs to implement mitigation measures for environmental impacts. In addition, Cal-Am has estimated that an additional $9.0–18.7 million would be needed to revise the existing Cal-Am distribution system to receive, treat, and store the larger quantities of water emanating from the northern end of its distribution system and distribute them to the rest of the Monterey Peninsula (American Water Works Service Company 1997). Thus, the total capital costs for the Seaside Basin injection/recovery project are estimated to range from $17.1 million to $34.6 million. As noted above, the number of injection wells needed may be higher than indicated in these estimates. These costs do not include project mitigation measures. Estimated O&M costs for diversion, treatment, and transport of water from Carmel Valley to the Seaside Basin, and injection and recovery of the water, range from $433,000 to $596,000 per year, as shown in Table A-10. O&M costs associated with required improvements to the Cal-Am distribution system were not developed. Refinement of water yield estimates and costs (capital and operating costs) will be based on more extensive testing of the Seaside Basin Injection/Recovery Pilot Test Project in 1999, assuming that adequate water supplies are available to permit the tests. Implementation Timing and Project Life. For a full-scale injection/recovery project, at least 2 years would be required to obtain the needed water rights, water discharge, health-related, and construction permits from various local, state, and federal agencies. Based on MPWMD’s experience drilling wells and the upgrades that could be needed for Cal-Am’s water distribution system, completion of the project is estimated to take 2–5 years once permits are obtained, depending on the desired production capability and the associated Cal-Am system improvements that would be needed. Once installed, the project life of each injection well is expected to be 10–20 years, assuming regular maintenance, pump replacement, and other repairs. Environmental Issues. The primary environmental benefit of the Seaside Basin injection/recovery project is that Carmel River streamflow could be diverted for storage during winter, when environmental impacts would be minimal, for community use in the dry season. The project could not only help reduce potential adverse effects of existing production from the Seaside Coastal Subareas; it also would reduce diversions from the Carmel River in summer and fall, when such diversions are harmful. Environmental concerns include the quantity and timing of water diversions and related impacts on aquatic resources; aquifer geochemical compatibility issues; and construction impacts, particularly to nearby Seaside residents. Other Issues. Presently, very few potential sites are available in which to locate new injection wells because the existing distribution and production facilities are in a developed area with little available open space. This factor would complicate the process of determining locations for these facilities. Additional open space is available at the former Fort Ord firing ranges to the east, but the feasibility of using these areas for injection purposes is questionable because of concerns regarding access, water quality, and safety. This land is presently owned by the U.S. Army and will not be transferred until ordnance removal issues are resolved. The timetables for ordnance clearance and land transfer are unknown at this time, but these activities will likely take at least 5 years. MPWMD may be able to execute short-term lease agreements with the Army to facilitate well exploration and testing associated with the injection project. The outcome of such negotiations cannot be predicted at this time, however. Of the various groundwater development options described above, only injection and recovery in the Seaside Coastal Subareas appears to be a reasonably foreseeable, feasible alternative. MPWMD is actively pursuing this alternative and is presently evaluating potential yield through its pilot test injection well and additional monitoring wells that are planned for installation in winter 1999. Based on the results of the 1999 test project and an assessment of site availability for injection wells, a determination will be made regarding the feasibility of a specific full-scale project. This testing will also provide more reliable estimates of long-term water yield from the project. A major advantage of new injection/recovery facilities is that they would efficiently use existing resources and help solve existing environmental concerns in the Carmel Valley and Seaside coastal areas. The major disadvantage is that the quantity of potential yield is relatively small compared to the 10,730 af/yr needed to replace diversions in Carmel Valley in accordance with SWRCB Order WR 95-10. Also, because the source of the injected water is the Carmel River, production from the injection/recovery project in the Seaside Basin would not qualify for exemption from the one-for-one replacement requirement in Order WR 95-10. Thus, none of the water produced from injection/recovery wells could be used for new connections or remodels until the entire 10,730 af/yr was replaced or legalized.
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