San Diego is the only city in California seeking state reimbursement for testing the toxic lead levels in water at local schools, which has cost the city's water agency more than $400,000.
The city has done tests at 256 schools since early 2017, but must test an additional 45 schools over the next six weeks. State legislation requires water agencies to test every public school, regardless of whether the agency gets a request, by July 1.
Significantly more schools in San Diego County have been tested than in any other county in California since the state requirement began.
The state has received testing results from 552 schools in San Diego County, compared with 360 in Alameda County, 280 in Santa Clara County, 263 in Sacramento County, 193 in Los Angeles County and 169 in Orange County.
Of the schools tested by San Diego, only four have exceeded the level of lead where California law requires them to take action.
In the San Diego Unified School District, three affected campuses — Co-Operative Charter School 2, Emerson-Bandini School and Birney Elementary School — have fixed their problems.
The fourth school was a French-English learning academy called La Petite Ecole in Clairemont.
The requirement, which came in response to a national outcry over lead in drinking water at schools in Michigan, immediately prompted complaints from water agencies that it was an unfunded mandate by the state.
San Diego filed a test claim with the Commission on State Mandates in January, something no other water agencies have done. Written arguments in the case are due by June, with a hearing tentatively scheduled for November.
"It's a very long, drawn-out convoluted process with the state," Brent Eidson, deputy director of the city's Public Utilities Department, said by phone. "The state never intended to reimburse us."
If the commission rules against the city, San Diego's 275,000 water and sewer customers will be on the hook for the tests. If San Diego wins, every water agency in the state will be reimbursed for the tests it has conducted at local schools.
Eidson said it would be unusual for the commission to take a compromise position and order partial reimbursement.
"It's usually an up or a down," he said.
Lead in drinking water can damage the cognitive development of children.
When a campus is found to have elevated levels of lead, the schools are required to fix the problem, with water agencies only required to conduct follow-up tests.
Water agencies are required to test five drinking fountains or other water fixtures at each campus, with school officials choosing the fixtures.
San Diego Unified announced last summer that it would begin testing all fixtures and cover the added costs itself. The district also decided to raise the standard of what's considered a dangerous level of lead from 15 parts per billion to 5 parts per billion.
That makes the district's standard the same as the U.S. Food and Drug Administration's standard for lead in bottled drinking water.
Eidson said the lack of positive tests for lead shows that San Diego's water does not contain dangerous levels of lead and isn't corrosive. Lead in water typically comes from corrosive water extracting the lead from old pipes.
"The water itself, as it leaves our plant and comes to everybody's individual homes, is definitely lead-free," he said. "The question is whether the plumbing on your particular house, or in this case a school, has lead fixtures and is our water so corrosive that it is leaching lead."
Eidson said one reason for the low frequency of local positive tests might be that much of San Diego's water comes from the mineral-rich Colorado River.
He said those minerals, especially calcium, help create an internal lining that keeps the water separate from the pipes carrying it, which could prevent or reduce the leaching of lead.