WATSONVILLE – A decade-old push to fluoridate Watsonville’s water came up more than $1 million short in the bids for construction.

The California Dental Association Foundation must now decide whether to press forward or scrap the project.

“If they don’t pay for it, we won’t build it,” said Steve Palmisano, the city’s water division manager. “We don’t have that kind of money for unplanned projects.”

Nor would there likely be much support for the controversial water treatment aimed at preventing tooth decay. Watsonville voters narrowly approved an initiative banning fluoridation in 2002, and only after losing a court battle that went on for years, did the City Council, on a 4-3 vote, accept a $1.6 million grant from the dental foundation to build a system in September 2010.

Danville-based Mountain Cascade offered to build the project for $2.8 million, the lowest of five bids, according to the city. The high bid, submitted by Blocka Construction of Fremont, is for $3.5 million.

Spokeswoman Alicia Malaby said the foundation is reviewing the bids. She could not provide a time line for an answer.

“CDA (California Dental Association) and the CDA Foundation continue to believe in and support community water fluoridation and would like to see the entire state fluoridated in the near future,” a written statement from the foundation said.

Fluoridating Watsonville’s drinking water was anticipated to be costly because individual buildings and systems must be constructed at each of the city’s 13 wells and its pumping station on Corralitos Creek. But Palmisano said city officials and its consulting engineers were surprised at how expensive the bids were, especially in the current economic climate that’s left some contractors with too little work.

Palmisano said the dental foundation gave its OK to the design documents and requirements before the bidding package went out. He said there’s no way to shave expenses further, and the fact that the bids came in fairly close indicates an accurate reflection of the project’s cost.

California law requires cities of 10,000 or more people to fluoridate if an outside entity provides the funding.

According to the foundation, 23 million Californians, nearly 63 percent, receive fluoridated water through their taps. Watsonville would be the first in Santa Cruz County to fluoridate.

Most dental professionals and the Centers for Disease Control and Prevention vouch for its safety and effectiveness.

Opponents express concerns nevertheless and say they shouldn’t be forced to ingest the chemical against their will.