Parents say students at Hope Elementary in Carlsbad have been complaining about water quality for months, and on Monday the Carlsbad Unified School District confirmed a cross-connection between fresh and reclaimed water lines led to harsh drinking water quality for months.
According to Carlsbad's Municipal Water District -- which helped the CUSD determine the cause last Thursday -- a recycled water pipe at the school was connected to one of its regular water pipes. Water was shut off and students were sent home.
The campus reopened Monday with the city of Carlsbad's blessing after the cross-connection was fixed. The water district purged Hope Elementary's plumbing system with highly chlorinated water and let it sit overnight. On Friday, the chlorinated water was flushed with potable water, and water quality tests were performed and analyzed by a third-party lab, according to the CUSD.
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The CUSD believes the cross-connection could have occurred during a construction project on the Hope campus over summer break, but the district said it is still investigating.
The city said the school district did not submit plans for work on its recycled water system, which would have triggered an inspection from the city.
"The Carlsbad Municipal Water District is working with the school district and its contractors to help prevent cross-connections during construction projects moving forward," a statement from the city of Carlsbad said.
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Kelly Elementary School and Magnolia Elementary School had similar construction projects recently, but the district said there is no reason to believe drinking and recycled water lines there were crossed, too. Out of an abundance of caution, the district said it will perform water quality tests at those schools.
The CUSD said they hadn't received any reports of illness related to drinking water on campus before Thursday.
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Complaints began at the beginning of the school year in August, according to the district, first about irregular water color from some drinking fountains and in some classrooms.
Initially, the school contacted its contractor who indicated the issue "was aesthetic and would resolve upon flushing the system," the district said.
Then in November, students started complaining about the water's taste and smell.
The district said tests didn't indicate that the water was unsafe. However, the district clarified that testing "was performed to rule out harmful bacteria, but testing was not ordered that would have detected the higher levels of chlorine, water hardness, and alkaline content that is found in reclaimed water."
After more complaints about the water on Hope's campus were made in January, the district hired an independent consultant, the district said. Testing found "increased levels of chlorine, water hardness, and alkaline content."
The district determined last Thursday cross-contamination had occurred, which prompted officials to send students home and notify the city of Carlsbad to shut off the water.
Families were notified about the contamination in a letter sent Monday.
"Our kids have been talking about this since August, they've made this clear that there's issues with this," parent Jason Langston said. "And now for them to finally come out and make a statement and then just be kind of like, 'Oops. Sorry.' That's not a satisfactory answer."
The district ended Monday's letter with the following statement:
"We are sincerely sorry that this was not reported earlier. We relied on the reports and information from our contractors, construction and bond program managers that the water had been tested for safety, that the issue was aesthetic, and would resolve. We did not anticipate the cause of the problem, and we regret that we did not discover the cause sooner. Once we were alerted to the cause, we took all the steps necessary to prevent further exposure; to inform our community; and to resolve the problem."
The city of Carlsbad notified the State Water Resources Control Board and San Diego County's Department of Environmental Health, which is standard protocol when cross-contamination occurs.
