Bernson Proposes Repairing Empty Chatsworth Reservoir : Environment: Some express concern that the water storage plan would harm a wildlife refuge at the site.

Councilman Hal Bernson asked the City Council on Wednesday to consider redesigning the Chatsworth Reservoir, which has been drained for more than 20 years as seismically unsafe, so it will fill with runoff from future rainstorms as a drought-fighting measure.

Environmentalists reacted with concern, expressing fears for the wildlife refuge that now occupies the site.

Bernson’s request, which bypasses the usual committee process and is scheduled to be voted on by the council next week, would instruct the city Department of Water and Power to study the feasibility of repairing Chatsworth Reservoir and “declare a priority for filling the reservoir with storm water.”

Although recent rains and flooding “may have appeared to bring the city up to normal rainfall amounts, the city is still in a state of emergency in regard to insufficient water supplies due to drought conditions,” Bernson said in his motion.

“Unfortunately, the city has no means to capture and use most of the rainwater which falls over Los Angeles.”

The 580-acre reservoir was drained in 1969 for repairs. After the 1971 Sylmar earthquake, it was determined that the dams on either end were seismically unsafe, that repair would be costly and that the reservoir itself was outmoded, said DWP spokesman Ed Freudenberg.

“We have no idea how long it would take to repair. . . . We also want to see what the cost factor is,” said Bernson aide Ali Sar.

The reservoir and surrounding area has since become a 1,320-acre wildlife refuge, populated by a variety of birds and animals and maintained by the department with the help of volunteers from environmental groups. The area is a major West Coast resting place for Canada geese on their annual migration and home to thousands of the geese that winter in the Valley each year.

The area has also been frequently used as a movie location.

Repair of the dams was given a low priority after the department decided instead to construct several storage tanks in the western San Fernando Valley in the 1970s, Freudenberg said.

“There were storage tanks placed in the west end, which alleviated the need for emergency storage in that area,” he said. “We found out that our system could operate without” the reservoir.

The department has not studied the matter in recent years, Freudenberg said, but he suspects that repairing the dams and redesigning the reservoir to hold storm runoff would be very difficult.

“It’s not the kind of reservoir that has runoff,” he said. “It’s isolated from the drainage around it. It’s not like a Hansen Dam where you can allow floodwater to run in there. It would take quite a bit of engineering and expenditure to fill it with either potable water or runoff.”

The reservoir was built in 1918 to hold irrigation water for farms and ranches that dominated the Valley at that time, Freudenberg said. It was expanded several times, but at the time of its closure it was considered obsolete for the now-urban area.

Various uses of the site have been discussed in recent years, including several plans--the most recent in 1990--to build housing there.

Environmentalists have strongly supported preserving the land as wildlife refuge, which is now closed to the general public but available for specially arranged educational tours. It is not clear how repairing the dams and flooding the reservoir would affect the future of the wildlife refuge, city officials and environmentalists said.

Sar said that Bernson, who has opposed development at the reservoir in the past, will insist that the wildlife refuge be maintained if the reservoir is rebuilt.

But Bernson’s proposal has already has made some environmentalists nervous that the surrounding land will be opened to development.

“There is enough land around the lake bottom to preserve the wildlife sanctuary,” if the reservoir is refilled, said Helen Treend, president and chairman of Save Orcutt Community Inc., a nonprofit corporation which oversees the Chatsworth Reservoir Conservancy.

“The question that is most prominent in my mind is, would the DWP then change the status of the land around the reservoir proper?” Treend said. “We don’t want to see a free-for-all among developers for the remaining land.”