MPWMD

The principal elements of the Parsons ES evaluation include:

1. review and update facilities and estimated costs of a 3 million-gallon-per-day (MGD) project in Sand City (same capacity and location as the project brought to voters in June 1993);
2. determine the largest capacity project that could be developed at the Sand City site;
3. determine the feasibility of developing a seawater desalination project in the range of 7 to 14 MGD;
4. identify critical environmental and permitting issues, and
5. estimate costs for desalination projects in the range of sizes being evaluated in the study.

Sand City Site:The consultant determined that a 3 MGD project at the Sand City site is feasible and that a project as large as 5 or 6 MGD may be possible at that site. For a 3 MGD plant, the estimated costs are $28.3 million for construction, $2.0 to $2.7 million/year for annual operation and maintenance (O&M), and $5.1 to $5.9 million/year for the total annual cost (including financing for 15 years at 7% interest). For a 6 MGD plant, these costs would be $51.7 million for construction, $3.8 to $5.2 million/year for O&M, and $9.5 to $11.0 million/year for total annual costs. Estimated cost per acre-foot ranged from $1,830/AF to $2,560/AF. These cost estimates are preliminary and subject to change, depending on the resolution of permitting issues and, in the case of a 6 MGD project, determination of feasibility. The issues identified as (a) through (c) below would need to be resolved prior to pursuit of a desal plant in the size range of 4 to 6 MGD.

Other Sites: The feasibility of a larger desalination project (7 to 14 MGD plants) located near Marina or at Moss Landing is questionable due to factors such as:

1. environmental impacts of constructing a large number of Ranney collectors and pipelines in sensitive sand dune habitat,
2. constraints within the Cal-Am distribution system that could limit the ability to deliver water from the north end of the Cal-Am system,
3. National Oceanographic and Atmospheric Administration's (NOAA) concerns about the effect of large amounts of concentrated brine on flora and fauna in the Monterey Bay National Marine Sanctuary,
4. adverse effects on dispersion of treated wastewater if the ocean outfall from the Monterey Regional Water Pollution Control Agency treatment plant north of Marina were used to discharge brine, and
5. availability of a secure seawater source at the Moss Landing Power Plant given PG&E's plans to sell the facility.

Rough cost estimates were developed for projects that would produce 7 to 14 MGD at Marina and Moss Landing, assuming they were feasible. Capital costs ranged from $70 to $126 million. The estimated O&M costs ranged from $4.4 to $9.0 million/year. The total annual costs ranged from $12 to $26 million/year. Estimated cost per acre-foot ranged from roughly $1,800/AF to $2,700/AF. These cost estimates are preliminary and subject to change, depending on additional investigations to determine feasibility and the ability to adequately address environmental issues.