RIVERSIDE - A western Riverside County water agency is set to discuss today a request to serve water to the proposed Liberty Quarry, which would be built southwest of Temecula just north of the Riverside-San Diego county line.

Western Municipal Water District's board is scheduled to take up the matter at its 9:30 a.m. meeting at district offices, 450 E. Alessandro Blvd., Riverside. No decision is expected.

Granite Construction Co., which wants to build the quarry, earlier asked the Rainbow Municipal Water District to provide water to the site from just across the county line. But the Rainbow district's board unanimously rejected the idea twice, with the most recent decision coming in April.

That prompted Granite Construction to turn to Western, the primary source of drinking water along the Interstate 15 corridor in western Riverside County.

Granite proposes to mine 5 million tons of rock from a 155-acre quarry it wants to establish in the mountains west of Interstate 15 and north of Rainbow Valley Boulevard. The mine would be active for 50 to 60 years.