Map is from the LOCSD’s environmental report on a project to tie-into the state water pipeline [Chorro Valley Pipeline] that runs along Hwy 1 [at the left side of the map), down South Bay Boulevard to Los Osos and the 16th Street tank farm. Map courtesy LOCSD
The Los Osos Community Services District has approved the environmental review of a project that would build a pipeline to Hwy 1 and tie-into the water pipeline that delivers drinking water to Morro Bay.
The LOCSD’s Board of Directors on Dec. 7 approved the staff’s “negative declaration” or “neg-dec” environmental review for the “Water Supply Resiliency Intertie Project” (Intertie Project) a scheme to initially bring 200-acre feet a year of State Water Project water to Los Osos and supplement the existing groundwater supplies, which have been in overdraft status for some three decades.
Though there are three water purveyors in Los Osos, they all have straws (wells) dipping into the same groundwater basin, Los Osos’ sole source of drinking water. Because of the over-pumping, seawater has been intruding far inland in the water basin.
SWCA Environmental Consultants of San Luis Obispo prepared the Intertie Project’s environmental review, which the board got last week. The neg-dec simply means that no environmental impacts were found with the project that can’t be either avoided or fully mitigated.
The project would, “allow delivery of potable water to the LOCSD’s water distribution system, which would reduce the amount of local groundwater pumping from the Los Osos Groundwater Basin and provide further protection against seawater intrusion,” the neg-dec’s introduction said.
The project seeks to tie-into the Chorro Valley Pipeline, which runs along the north side of Hwy 1 through Chorro Valley, and build a pipeline from there to the LOCSD’s 16th Street water storage tanks, which the neg-dec said was only 2.5 miles.
“The intertie [to the Chorro Valley Pipeline],” the report said, “would be constructed to the north of the southbound lane of Highway 1 and the proposed pipeline alignment would begin at this location, cross under Highway 1 and extend south toward Quintana Road, west along Quintana Road toward South Bay Boulevard, south along South Bay Boulevard, and would terminate at the LOCSD’s basin at the intersection of Santa Ysabel Avenue and South Bay Boulevard.”
That alignment would place the actual tie-in somewhere near the intersection of Quintana and Hwy 1 (San Bernardo Creek Road on the other side of the highway).
The Morro Bay City Limits extend out Quintana from South Bay Boulevard and down South Bay a ways past the intersection with State Park Road (in the “S” turns).
“The entire project,” the report said, “would be located within the public right-of-way and within the unincorporated San Luis Obispo County, under the jurisdiction of the County of San Luis Obispo, except for the portion of the project beginning approximately 600-feet north of the Cerro Cabrillo Trailhead/Quarry Trailhead parking lot/turnout [on South Bay] to approximately 1,200-feet south of the South Bay Boulevard and Quintana Road intersection, which would be located in Morro Bay city under the jurisdiction of the City of Morro Bay.”
It may only be partly located in the City Limits, but the entire project is within the coastal zone and under the watchful eye of the Coastal Commission, which the LOCSD GM said has appeal authority.
“I have had several discussions with the County,” LOCSD General Manager Ron Munds told Estero Bay News, “and they are supportive of the project but there hasn’t been any type of official negotiations yet. Morro Bay does not own the Chorro Valley Pipeline; the County owns it so the CSD does not need their permission to connect. We will need an encroachment permit to install the pipeline within their City Limits.”
Morro Bay solely paid for much of the Chorro Valley Pipeline (CVP) as part of its subscription to the Coastal Branch of the State Water Project, which had been in the planning for decades and was built and completed in the mid-1990s. It delivers State Water from a treatment plant — Polonio Pass — off Hwy 46 and provides drinking water to subscribers in SLO and Santa Barbara Counties. The Central Coast Water Authority owns and maintains and operates the plant and the Coastal Branch Pipeline.
Morro Bay is the last subscriber hooked into the CVP, which dead ends at the City’s Kings Street tank farm. The City gets 1,313-acre feet a year, with a like amount in reserve, a so-called “drought insurance” allocation.
Excess water, which the City didn’t ask be delivered in a given year, is stored in the San Luis Reservoir, one of the main reservoirs for the whole State Water Project system (plus the Federal Central Valley System).
According to the County’s “Integrated Regional Water Management Plan” from 2020, “The Chorro Valley Water System includes these entities: CMC, Camp San Luis Obispo, Cuesta College, and San Luis Obispo County Operations Center/Office of Education.”
That water system includes state water and water from the Whale Rock Reservoir (via the Whale Rock Pipeline), as well as numerous private water wells.
“CMC operates a water treatment plant (for Whale Rock water) to provide potable water to CMC facilities and wheels water to Camp San Luis Obispo, Cuesta College, County Operations Center (which includes Fleet Services, the Water Quality Lab, Juvenile Detention Center, County Jails, Office of Emergency Services), and the County Office of Education.
“These entities have several inter-entity agreements relating to entitlements to their shared water supplies, which include Whale Rock Water, Chorro Reservoir, and State Water. Camp San Luis Obispo also has first rights to one on-site well (County Well No. 1).”
Los Osos’ plan is to build the pipeline and take state water during drought and below average rainfall years, so it too should be able to build up a reserve bank of water, as Morro Bay has done.
Such a reserve bank of water comes in handy when the State cuts deliveries because of a low snowpack in the Sierras, where all that water originates.
The Coastal Commission has played a large role in Los Osos’ water situation having declared it would not approve any coastal development permits issued by the County if it means adding to the water demand and in turn the overdraft situation.
That decree has effectively placed a moratorium on CDP permits based on the water supply. This after the town fought over a sewer moratorium for over 30 years before the County finally got it built in 2016.
It remains to be seen if the commission will support this project to supplement the Los Osos water supply or if they will condition it to prevent growth in the community, which the halt on CDPs has effectively done. For now, they’re out of it.
“The neg-dec,” Munds said, “isn’t appealable to the Coastal Commission but the project will need a Coastal Development Permit from the County and Morro Bay. Those permits would be appealable to the Coastal Commission.”
The LOCSD also doesn’t need permission from its customers to proceed. Asked if the project would need a Prop. 218 — the Right to Vote on Taxes Act — vote, Munds said it didn’t.
“A Prop 218 vote,” Munds said, “is not required since the project will be paid by rates and charges, grants and possible low interest loans.”
And the price at this point seems almost like a bargain. “The preliminary engineering cost estimate is approximately $8 million dollars,” Munds said. “This would be shared with the other water purveyors who have expressed interest in the project.
“To put this into perspective, the Program C well we are working on will cost about $3 million but doesn’t add a drop of ‘new’ water to our water system [the groundwater basin].”
And because the community sewer system the County put in recycles much of the treated wastewater back into the basin, bringing water in from outside will add a certain amount to the basin after it’s run through homes and businesses and fully treated by the County. There’s a large leach field facility that goes with the County’s sewer system located above Broderson Avenue where water is to be recycled.
And because state water is treated with different chemicals than the LOCSD’s water, they will need to switch that out too. “The water purveyors,” Munds said, “will need to switch from using chlorine to chloramine for disinfection. This is not an issue. No added storage tanks will be needed. The CSD will use the two existing storage tanks on 16th Street as the terminus for the intertie pipeline.”
The project has a long ways to go and many of the details, like capacity, have to be worked out and ultimately designed into the project. Among these is the final capacity of the pipeline, as 200-acre feet a year and only when there’s too little rainfall, seems like a small of an amount of water to solve the town’s water issues.
How long is this project expected to take? “The timeline,” Munds said, “is difficult to estimate at this point. It is the CSD’s hope to have the project well underway later in 2025. The initial 200-acre feet is the amount estimated that is needed to offset water production [pumping] in the basin that will halt and maybe reverse the seawater intrusion the groundwater has been experiencing for many years. There will be extra capacity in the pipeline if needed in the future.”
It’s important to decide up front just how much water the town wants to get. The County Flood Control District has thousands available, and once a pipeline is installed, the capacity will be set.
