MODESTO -- Leaders of a farmer coalition that watches over water quality are urging nonmembers to get on board soon.

The group, the East San Joaquin Water Quality Coalition, can help farmers meet standards at a much lower cost than direct regulation by the state, it says.

A new round of sign-ups started Monday and will run through May 13, executive director Parry Klassen said.

That followed a state agency's decision last month to continue the coalition approach. It started with surface water in 2003 and will expand to groundwater.

The coalition covers irrigated land in the parts of Stanislaus, Merced and Madera counties east of the San Joaquin River. It is one of several such groups overseen by the Central Valley Regional Water Quality Control Board, a state body.

Dues from farmers pay for sampling of water for pollution from pesticides, fertilizer and other farm sources. The coalition also educates growers about practices that can reduce the threat.

The current annual dues are $50 per farm plus $4 per acre.

The coalition membership covers about half of the 1.1 million irrigated acres within the boundaries. It does not include dairy farms, which are regulated under another program.

Deadline looming

Farmers who do not join the coalition by May 13 will have to get individual permits from the state and pay higher dues. They will have to do their own sampling, which could include installing monitoring wells.

"I hope they take advantage of this opportunity to sign up within this 120-day period, because then they're just dealing directly with the coalition," said Joe Karkoski, the irrigated-lands program director for the water board.

The East San Joaquin coalition is the first in the Central Valley to get renewed authority to monitor water. Karkoski said others could follow over the next year, including one for land west of the San Joaquin River and another for San Joaquin County and the Sacramento-San Joaquin Delta.

More information on the East San Joaquin Water Quality Coalition is at www.esjcoalition.org.