Silicon Valley’s largest drinking water provider will begin to take up the issue Tuesday of whether to put fluoride in San Jose’s drinking water.

The board of the Santa Clara Valley Water District will hold an informational public workshop at its meeting at 5:30 p.m. at the district’s headquarters, 5700 Almaden Expressway, in San Jose.

San Jose is the largest city in the United States without fluoride in its drinking water. Other Bay Area cities have had it for years, including San Francisco, which fluoridated its Hetch Hetchy water starting in 1972.

The San Jose municipal water system, which serves about 125,000 people in North San Jose and Evergreen, does fluoridate its water. But the San Jose Water Company does not.

Health advocates, led by the nonprofit Health Trust of San Jose, have been pushing for San Jose and other cities in Santa Clara County without fluoride in their drinking water to add it, citing research showing improved dental health.

They have released studies that reveal high rates of tooth decay among children in Silicon Valley, particularly low-income children without dental insurance.

The key question is who would pay. A study completed this month by the San Jose Water Company, a private company that buys water from the water district and provides it to 1 million residents of San Jose and nearby communities, estimated the cost to retool its system to provide fluoride at $23 million, with $1.7 million a year in operations and maintenance costs.

The board will not take a final vote at its meeting Tuesday. It plans to hold other public meetings throughout the year to debate and discuss the issue in more depth.

For more information, go to www.valleywater.org and click on “Board of Directors meetings.”