It's full stream ahead for Lower Owens They're watching the river grow

Beneath him, the squiggle of green was overflowing its banks, inundating a patchwork of oxbows, marshlands, forests and sagebrush. Culverts were nearly filled to capacity, and mats of dislodged tules and muck hurtled down the river.

"I really like what I see down there," the 80-year-old Platts told the chopper pilot through the headphone radio. "But we'll need three or four more seasonal pulses to kick-start this ecosystem into gear."

The Lower Owens River has flooded for millenniums, but this flood was man-made, part of the most ambitious river restoration project in the West. The river mostly disappeared when the Los Angeles Aqueduct opened in 1913, but 15 months ago engineers began redirecting some aqueduct water into the channel.

The flood should flush the recently revived river of a century's worth of cattle waste and debris, add topsoil to its flood plain and spur an awakening of riparian rhythms without harming fish populations. Eventually, a canopy forest will grow along the 62-mile river, and Inyo County officials hope the waterway will support a thriving recreation industry.

But whether the project achieves that potential will depend on three river bosses who rarely agree: the Los Angeles Department of Water and Power, Inyo County and environmentalists whose lawsuit led to a judicial order that launched the 77,657-acre project as mediation for environmental damage from DWP pumps sucking out groundwater.

Some suggest that the effort also might be affected by drought conditions, which could reduce interest in the project that runs on 55,000 cubic feet of Sierra snowmelt a year.

"If there was not enough water to go around and people were suffering, this project would be the first thing to go," said project consultant Mark Hill, who helped develop the plan along with Platts. "It's sacrosanct now and under a court order. But no one should think it's set in stone. It's not."

Early signs, however, are hopeful. With Los Angeles Mayor Antonio Villaraigosa's support, the DWP has pledged stewardship of the river that until December 2006 existed as a nearly dry riverbed. A few spring-fed ponds sustained fish and beavers, but the channel was mostly choked by weeds and trampled by cattle.