The Cayucos Sanitary District was formed on March 2, 1942 for the purpose of constructing and operating a sewer collection system and a treatment plant. The District is an independent special district established pursuant to the Sanitary District Act of 1923 (Health & Safety Code §6400, et seq). 

Sanitary districts are empowered to acquire, maintain and operate sewer, drainage and/or refuse collection facilities.  They may incur bond indebtedness, enter into contracts, borrow money and charge service rates.  Cayucos Sanitary District provides wastewater service to the community of Cayucos which entails collecting wastewater within the community and conveying it through a main line to the Water Resource Recovery Facility located on Toro Creek Road.  The District’s wastewater system encompasses five lift (pump) stations and approximately 23.1 miles of gravity collection sewers.

The District is governed by a Board of Directors consisting of five members who are elected by popular vote for terms of four years. Administration is carried out through a staff of eight: three field personnel, two office staff, two plant operators and led by a contracted Engineer/District Manager.  As a complement to the staff, the District maintains Legal Counsel and auditing services.

District Creation

Cayucos Sanitary District was formed by democratic election held on February 17, 1942 with fifty five (55) votes in favor and one (1) opposed, and certified by the Board of Supervisors of San Luis Obispo County on March 2, 1942.  The first official record of any activity is that of a special meeting of the governing board, consisting of D.R. Pereira, A.K. Hardie, L. Molinari, Howard Hilton and Al Brewer on January 4, 1951, with Periera presiding.

On March 17, 1953 voters approved a bond issue of $171,000.00 for construction of mains, trunks, pump stations, etc., and to pay Cayucos’ share of the cost of a treatment plant to be located on Atascadero Road and to be jointly owned by Morro Bay and Cayucos Sanitary District.

On October 22, 1953, the District advertised for bids for construction of a collection system designed by Daniel, Mann, Jonson & Mendenhall, and as the successful bidder, Coastal Pipeline Contractors was awarded a contract at a special meeting on December 29, 1953.

By means of a quitclaim deed from the County of San Luis Obispo dated May 18, 1953, the Cayucos Sanitary District became owners of 40% and the Morro Bay Sanitary District 60% of Blocks 28A and 28B and 28C on Atascadero Beach Road as a site for a sewage treatment plant.

A joint construction and operating agreement was executed on June 16, 1953, authorizing Morro Bay Sanitary District to act as agent for both Districts in the construction and operation on the treatment plant, outfall and the common trunk line which extends from a point just north of Yerba Buena Avenue south to Atascadero Road, then west to the plant.   In 1954 the District constructed the sewer system and treatment plant under a Joint Powers Agreement (JPA) with the Morro Sanitary District (now the City of Morro Bay).  That JPA was subsequently amended in 1969 and 1973. 

In 1982 the District and City of Morro Bay renegotiated the Joint Powers Agreement governing their jointly owned wastewater treatment plant facility and agreed to reconstruct and expand the wastewater treatment plant at an estimated cost of $13,000,000.  Additionally, the ownership percentage was reconfigured to provide Cayucos Sanitary District with 35% ownership and the City of Morro Bay 65%, however, the District retained 40% ownership in all jointly owned real property.

Morro Bay-Cayucos Sanitary District Wastewater Treatment Plant (WWTP) Project

In 2005, the Morro Bay City Council and Cayucos Sanitary District (MBCSD) Board adopted an eight (8) year full secondary compliance schedule for upgrading the treatment process at their jointly-owned wastewater treatment plant to comply with full secondary treatment standards by no later than March 31, 2014. Carollo Engineers completed the Facility Master Plan for the WWTP Upgrade in final draft form.

On May 28, 2008, a contract was let for environmental review to Environmental Science Associates. A flood analysis was performed by Wallace Group Engineers as a component of the environmental review. As a result of the flood analysis, it was determined that the flood mitigation costs to complete the upgrade of the current WWTP were prohibitive and the upgrade would need to take place adjacent to the existing plant. On December 4, 2008, the City and District were granted a final 5 year 301(h) modified NPDES permit from the State Water Resources Control Board for continued discharge from the WWTP to the ocean outfall. This permit was to cover the majority, if not all, of the WWTP Project when full secondary treatment standards were achieved.

On January 11, 2011, the Morro Bay City Council conditionally approved a Coastal Development Permit (CDP) for MBCSD's request to upgrade the existing WWTP and certified the Environmental Impact Report (EIR) for the proposed project. The City's approval of the CDP was appealed to the California Coastal Commission (CCC). As a result of the appeal, the CCC asserted jurisdiction over the project's CDP. Per CCC Staff direction, MBCSD conducted an additional WWTP Alternatives Analysis to evaluate whether there would be a more appropriate site to locate the WWTP.

In January 2013, the California Coastal Commission voted to deny the Coastal Development Permit for a proposed upgrade at the existing MBCSD WWTP. The CCC recommended that a new facility should be located outside the coastal zone and provide a sizable reclaimed water component. Due to the CCC’s decision to deny the CDP to build an upgraded WWTP at the location of the current MBCSD WWTP, the District opted to move forward with the study toward development of an independently owned and operated WRRF (Wastewater Resources Reclamation Facility) rather than continue partnering with the City of Morro Bay for treatment of its wastewater.

Cayucos Sustainable Wastewater Project

In February 2015, the City of Morro Bay presented the District with a Memorandum of Understanding (MOU) detailing the payment and governance structure of a new Wastewater Treatment Facility at the City of Morro Bay chosen facility site, Rancho Colina. At a JPA meeting, the Cayucos Sanitary District staff and Board presented a revised MOU to the City of Morro Bay based on the principals of the existing JPA’s cooperative co-ownership and governance structure. The District was informed by the City of Morro Bay that the MOU terms were non-negotiable.

Presented with a non-negotiable MOU, the District held a town hall open public meeting on April 23, 2015 to discuss options with the community. There was overwhelming support for the CSD to pursue options for the creation of a community treatment facility with the ability to produce reclaimed wastewater in order to help provide a sustainable water supply for the community’s future.

On April 30, 2015 the CSD Board unanimously passed Resolution 2015-1 ceasing all participation with City of Morro Bay with respect to their new wastewater treatment facility. In June 2015, the CSD initiated contracts for beneficial use analysis, side constraints and wastewater characterization studies. These studies were presented to the public at a town hall meeting in January 2016.

On April 20, 2017, the Board held a Proposition 218 hearing that put in motion the five-year rate increase to establish the monthly sewer charges. The proposition established a 5-year rate increase effective each July 1, beginning in 2017.  Also, during the April 20, 2017 meeting, by unanimous roll call vote, the Board approved Resolution 2017-3 certifying the CSWP FEIR (Final Environmental Impact Report).

The CSD broke ground in August 2018 on the aptly named Cayucos Sustainable Water Project. The CSWP includes a new $25M sewer treatment plant at 800 Toro Creek Road featuring a Membrane Bioreactor (MBR) treatment facility, infrastructure to convey plant discharge to the ocean outfall, reconfiguration of the pipeline system controlling inflow and outflow through Lift Station 5, and a solar field to mitigate electrical costs. Reclaimed water is to be available for onsite and local agricultural uses.  Future plans include diverting the reclaimed water into Whale Rock Reservoir, thereby increasing the availability of water available to Cayucos by approximately 350 acre feet annually. 

The Cayucos Sanitary District Water Resource Recovery Facility was dedicated to the Community of Cayucos and its sustainable water supply in June of 2021.  Pumping to the Morro Bay Waste Water Treatment Plant ceased on September 14, 2021.