LAKE COUNTY, Calif. — Officials on Friday said they have expanded the incident area for a massive sewer spill in the northern part of Clearlake as a precautionary measure.
Sunday will mark three weeks since a Lake County Sanitation District-owned force main rupture triggered the Robin Lane sewer spill, which released nearly three million gallons of raw sewage into streets and across private properties.
On Monday, the city of Clearlake began managing the recovery phase of the incident in unified command with the Lake County Sheriff’s Office of Emergency Services.
During the week, officials expanded the number of impacted properties from 58 to 200.
By Friday, the unified command said that, based on continued evaluation of groundwater conditions related to the spill, the incident area was expanded as a precautionary measure to ensure the protection of public health.
When the sewer line break was first identified, officials said an initial impact area was established based on the information available at that time, including where groundwater from the shallow aquifer was believed to have the potential to be affected.
“After further review and consultation with a hydrogeologist, it was determined that groundwater in the area may have moved more laterally than originally anticipated,” the Friday unified command report said.
As a result, unified command expanded the incident area to include additional residents who rely on private wells drawing from the shallow aquifer.
Three new incident zones were created for properties north of Burns Valley Road that are east of Reid Lane and south of Pond Road, which comprise the new Zone A3, and properties north of Olympic Drive that are east of Old Highway 53, and west of Highway 53, which are included in zones C3 and C4.
Those zone changes — which bring the total number of zones to nine — resulted in the new incident area growing from about 297 acres to an estimated 550 acres, based on an analysis of the city map released by city and county officials.
“Inclusion in the expanded area does not mean contamination has been confirmed at a property. The expansion is intended to ensure that all areas that could potentially be affected receive appropriate guidance, testing and support,” officials said.
Following the recommendation of Public Health Officer Dr. Robert Bernstein, residents within the expanded area are advised not to use their well water until water sampling and laboratory testing have been completed and results confirm the water is safe for use, according to the Friday report.
Officials said Friday that additional groundwater testing and evaluation will continue as part of the ongoing response, and residents will be notified directly about testing and next steps as more information becomes available.
Friday’s recovery update also included new figures for testing, with 151 sites tested and 376 water samples completed.
Additionally, 25 water tanks have now been installed, 18 of them by the incident management team and seven through a program administered by Lake County Social Services.
For residents without water, the mobile laundry and hygiene service trailer is located at 2485 Old Highway 53 in Clearlake.
Residents with questions may contact Lake County Environmental Health at 707-263-1164 for well testing and the city of Clearlake at 707-994-8201 for general information.
Updates, maps, testing information and available resources are available at the city of Clearlake's website or Response.LakeCountyCA.gov.
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