By Sam Richards
CONTRA COSTA TIMES
An accidental release of high levels of fluoride into Pleasanton’s city water system early Monday appears to have had few, if any, adverse effects, say city officials.
Contractors had shut down the water system to replace a valve at the city’s pumping station at Santa Rita Road and Black Avenue and created a “negative pressure” resulting in the release of enough fluoride to put 75 to 80 times the standard amount in drinking water, said Scott Baker, an assistant public works director.
The release occurred about 4 a.m. at the pumping station next to Alisal Elementary School on Santa Rita.
City water employees went door to door in the Jensen Tract subdivision south and east of the school, warning residents not to drink tap water before running faucets for 10 to 15 minutes.
By midday Monday, Baker said they had not heard of any instances of people getting sick from drinking water.
Though fluoride is added to city water to help prevent tooth decay, especially in youngsters, fluoride in high doses can cause nausea and diarrhea, Baker said, with symptoms likely to surface within a few minutes. Using tap water for any other purpose, even brushing teeth, probably wouldn’t cause problems, he said.
“You’d have to drink a fair amount for it to cause any health problems,” Baker said.
Students at Alisal were told Monday to refrain from drinking from fountains there until late morning, said school district spokeswoman Jerri Long.
Baker said tests showed that, by noon, the tap water near the pumping station was again safe to drink.