Movement on the Los Osos Sewer Project

by Jack McCurdy

Synopsis:  After four years of little or no progress, the Los Osos sewer project has been finally approved in broad outline by the California Coastal Commission, but stringent conditions and monitoring by the Commission staff of the project's development by the county will determine whether the Commission will ultimately grant the necessary permit to actually build it in the future. 

The hotly-debated Los Osos sewer project, immobilized for four years by a lack of community and governmental consensus on what to develop and mired in ongoing controversy across the county, appears to have turned the corner with approval of a general plan by the California Coastal Commission—but with stringent conditions and required monitoring by Commission staff to ensure that it maximizes protection of the environment and serves Los Osos residents as effectively and economically as possible.

Among the conditions is a requirement that the project must provide for recycling of wastewater for "urban and agricultural irrigation" and to "maximize long-term ground and surface water" by improving "the health and sustainability" of the "underlying Los Osos groundwater basin," or aquifers.

Recycling is also a core issue in the planning of the Morro Bay-Cayucos wastewater plant. The conditions for the Los Osos project would indicate the Morro Bay-Cayucos will also have to include recycling, under Coastal Commission standards reflected in those conditions.

A big question not yet answered is: how much will either sewer treatment project cost the public and ratepayers. 

The staff report adopted by the Commission on June 10 said the plan "represents an important environmental enhancement project of statewide importance that will greatly improve environmental health and safety associated with ground and surface water in and around Los Osos, including in Morro Bay, and including with respect to its related habitat resources." Morro Bay refers to the Morro Bay National Estuary.

It is a project that follows the guidelines established by the Commission in January when the county's plan was rejected as insufficient.

Now, the county can go forward and develop a specific plan and design for a complete sewer system, including a wastewater treatment plant, collection/disposal/reuse facilities and all associated development and infrastructure. The treatment plant would be located at 2198 Los Osos Valley Road.

Under the Commission's action, its staff will monitor the county's progress toward this end and ultimately will pass judgment on the completed design and plan to determine if it meets the conditions just adopted for issuance of a permit to develop.

Those conditions include:

—Plans showing revised treatment plant and pump station layout to avoid habitat issues, 
—Revised treatment plant access road to avoid agricultural impacts, 
—Details on measures to be taken to ensure all project landscaping is limited to native and non-invasive species,
—A habitat management plan defining restoration, enhancement, management, and protection of the 80-acre Broderson site, the 12-acre Mid-Town (Tri-W) site, the roughly eight-acre habitat/buffer area at the Giacomazzi site, and about an acre at the various pump stations sites (a total habitat management plan area of about 100 acres)
— Agricultural easements . . . to address agricultural impacts at the treatment plant site and access to it,
—A septic system decommissioning plan to identify measures to appropriately decommission existing septic tank systems and to connect users to the approved project,
—A restriction on service to undeveloped Los Osos properties absent an LCP (Local Coastal Plan) amendment that identifies appropriate and sustainable buildout limits,
— An overall Los Osos basin recycled water management plan designed to ensure that the location of the wastewater disposal maximizes long-term ground and surface water and related resource (including wetlands, streams, creeks, lakes, riparian corridors, marshes, etc.) health and sustainability, including with respect to offsetting seawater intrusion as much as possible, through aggressive recycled water reuse, water conservation, monitoring, and adaptive management,
—A methodology for future CDP (Coastal Development Permit) amendments and for resolution of potential conflicts, and require the County to indemnify the Commission against third party lawsuits.  

The Commission report underscored the importance of recycling wastewater by saying:

" . . . although the core proposed project is a wastewater project, it will also significantly affect groundwater and thus water supply, and the two issues are not readily separated. Nor should they be, particularly given that this is a significant and expensive public works project. This opportunity should be taken to address on-going public service needs as comprehensively as possible, including with respect to the manner in which the location of the disposal of the treated wastewater can be used to maximize its groundwater/water supply utility within its basic framework."

The proposed treatment plant would be sited on approximately 30 acres located about one-half mile inland of Morro Bay at 2198 Los Osos Valley Road, just past and north of the Los Osos Mortuary and Memorial Park, known locally as the Giacomazzi site, the report said. Proposed collection, disposal, and reuse infrastructure would be located throughout Los Osos, with the primary effluent disposal leach field proposed for eight acres at the top of Sea Horse Lane, known locally as the Broderson site. 

The report said the "project would treat wastewater to a tertiary level (known as the ultimate disinfectant state) and would reuse as much of the treated effluent as possible for urban and agricultural irrigation with disposal prioritized to reduce seawater intrusion and otherwise improve the health and sustainability of the underlying Los Osos groundwater basin."

Other "complementary" components for water conservation include proposed mitigation for project impacts, including restoration and  permanent protection of about 80 acres of sensitive habitat at the Broderson site (including restoration and re-restoration of the leach field area as it is periodically disturbed) and about six acres of habitat buffer area at the Giacomazzi site, the report said. 

Only existing developed properties would be allowed to hook up to the new wastewater system with a requirement that "a communitywide Habitat Conservation Plan (HCP) and an LCP amendment precede development on undeveloped properties in Los Osos to ensure that habitat is protected and that there are adequate services for any new future development consistent with Coastal Act and LCP objectives."

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