The purpose of these recommendations is to provide guidance to: 1) applicants proposing desalination projects, and 2) the Coastal Commission staff in working with applicants and reviewing applications for permits for desalination plants. The Coastal Act and LCPs are the standards for review of permit applications. All the technical information needed and the permits required from other agencies should be provided by the applicant when a permit application is filed. In addition, the Coastal Commission headquarters' and districts' staffs will work closely together to ensure that consistent standards of review are applied statewide.
The Coastal Commission staff should become involved in a desalination project proposal as early as possible in applicable planning processes, including but not limited to those mandated under CEQA and/or NEPA, before the decision to build a plant is final. Desalination proposals should be considered in the context of an overall water management plan. For example, all opportunities for water conservation and reclamation should be implemented in the area proposing to build a desalination plant. In addition, water supply alternatives such as drawing water from an existing aqueduct or reservoir should be considered. Alternative sites and alternative desalination technologies should be fully considered so that potential adverse environmental impacts from the plant can be avoided or minimized.
Applicants for desalination projects are encouraged to consider possibilities for cogeneration, alternative energy technologies, and technologies that reduce energy use. The applicants should submit estimates of the projected annual energy use and the environmental impacts that will result from this energy production. For plants that will require significant new electricity generation, the staff should work with the local Air Pollution Control District (APCD) to ensure that adequate offsets will be provided if required. In these cases, applicants should submit with the permit application evidence of compliance with air pollution control laws for emissions from the electricity generation.
Desalination plants can use either a pipeline into the ocean or beach wells for intake of seawater. Beach wells have the significant advantage of eliminating impingement and entrainment impacts. Applicants are encouraged to use beach wells for seawater intake whenever feasible, and where the wells will not cause significant adverse impacts to either beach topography or potable groundwater supplies.
Applicants are encouraged to select technologies and processes that minimize or eliminate the discharges of hazardous constituents into the ocean. The applicant should ensure that the least environmentally damaging options for feedwater treatment and cleaning of plant components are selected.
Applicants should evaluate the options for combining brine discharges with discharges from a power plant or a sewage treatment plant. Combining the brine with power plant cooling water discharges is probably the form of ocean discharge that will have the least damaging impacts because the brine would be diluted. Mixing with sewage treatment effluent may also be preferable to direct discharges of brine, but more information is needed.
When the brine will be combined with other discharges, the applicant should clearly identify which party or parties will be responsible for monitoring the discharges and for providing corrective measures for any adverse impacts that occur. When more than one party is involved in discharging the effluent, the staff may require co-applicancy for the permit.
Applicants should provide as much information as possible about the potential impacts to marine resources from the proposed discharges. This information may be obtained from pre-operational monitoring, monitoring results from other desalination plants, and pilot plant studies conducted before building a full-scale plant. The information should be reviewed by the Coastal Commission staff in consultation with the RWQCB with jurisdiction in the area where the plant will be located.
The Commission staff will need to consider the information contained in the NPDES permit as part of its review of the coastal development permit application. The staff should work with the RWQCB to ensure that the applicant will provide the pre- and post-operational monitoring information needed to evaluate the marine resource impacts of the plant. The coastal development permit should require that 1) the Executive Director receive copies of all monitoring reports submitted to the RWQCB, so that the staff may evaluate the marine resource impacts of these plants and 2) the applicant provide evidence to the Executive Director of NPDES permit renewals for discharges from the plant.
The Commission staff should review monitoring information provided by the desalination plant operator and, to the extent permitted by Section 30412 of the Coastal Act, either strengthen existing regulatory requirements to minimize or eliminate any adverse impacts that such information documents or modify the monitoring requirements to improve the information collected on a particular problem. In the alternative, the staff should work with the SWRCB and RWQCBs and their respective staffs pursuant to Section 30404 of the Coastal Act to accomplish these same objectives.
Subject to the limitations maintained in Section 30412 of the Coastal Act, if the Commission staff believes that the RWQCB's monitoring requirements are not adequate to provide the information needed to evaluate the marine resource impacts of a plant, the staff should include permit conditions that specify the additional information needed.
In evaluating a proposal for a desalination plant, the Commission staff should consider whether the water provided will meet only the existing needs of the community or private development or will provide additional water supplies, which may allow opportunities for growth. Water supplies made available through a desalination plant should be no more than the level to support development potentially allowable under the certified LCP.
If an applicant submits a proposal to build a desalination plant to meet emergency water supply shortfalls, the staff should evaluate the proposal to determine if the plant is designed in a manner that will allow for easy removal of the structure with minimal environmental impacts after the emergency has passed. The permit should include a condition that stipulates the time for which the permit is valid and that requires the applicant to apply for a new permit to extend the life of the plant if required. The permit should specify the permitted capacity of the plant; the applicant must subsequently comply with the capacity limitation stated.
As part of periodic reviews of LCPs in water-short areas, the Commission staff should consider water supply issues and potential growth-inducing impacts from water supply. LCPs should encourage use of conservation and reclamation measures to reduce the need for new water projects. LCPs should also specify the quantity of water supplies that will be needed for the planned levels of development.
Applicants for desalination projects should evaluate cumulative impacts in their Environmental Impact Reports. The Commission staff will work with local and state agencies to consider the potential cumulative impacts of desalination projects. Among the important issues to consider are: the impacts from building a number of small plants versus a few larger ones; the potential impacts of short-term projects if they continue to operate in the long term; the potential impacts on growth from the additional water supplied by a number of projects; and the environmental effects of additional power production if needed for operation of desalination plants.
The Coastal Commission, local governments, the Department of Water Resources, and other agencies should establish criteria for determining when a desalination project is appropriate for supplying water, and when alternative water supply options are preferable. The Commission should encourage local entities to use all options for water reclamation and conservation.
The Commission should consider establishing and/or participating in an interagency task force to address issues surrounding desalination. The task force should include agencies such as the Bay Conservation and Development Commission, the Department of Fish and Game, the Department of Water Resources, Regional Water Quality Control Boards, the State Water Resources Control Board, and other local, state, and federal agencies, local governments, and water management agencies.
The Commission should encourage research on the marine resource and water quality impacts of discharges from desalination plants.
Water is often the limiting factor for potential development projects and growth within a community. Because public ownership and operation of desalination plants may be a significant contributing factor in ensuring that initial development of desalination plants and subsequent water allocations are consistent with the development priorities mandated in the Coastal Act or incorporated in a certified LCP, the Commission should evaluate whether special or additional conditions may be necessary or appropriate in connection with any approvals it may grant to privately-owned desalination plants.
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Chapter 4: Regulatory Authority and Legislative Issues Related to Desalination Plants
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