Mimicking Nature : Reclaimed Water May Be Used to Bolster Irvine Marsh

In an effort to provide a thirsty ecosystem with water once supplied by nature, the Irvine Ranch Water District hopes to pump millions of gallons of reclaimed water into one of Southern California’s largest freshwater marshes.

The Regional Water Quality Control Board will consider the San Joaquin Marsh project in February. If approved, it would get under way next fall.

Environmentalists are divided over the plan. Some consider it a novel way of delivering needed water to the marsh’s plant and animal life. But others fear the pumping will do more harm than good.

The district hopes the pilot project will demonstrate that reclaimed water can take the place of natural freshwater that was provided to the marsh by San Diego Creek before it was rerouted in the late 1950s.

“The idea would be to mimic nature,” said Ronald Young, general manager of the water district. “We would add the (reclaimed) water during the rainy season. . . . As the water flows through the marsh, it provides the necessary ingredients for the marsh’s health.”

If the program is successful it could become permanent, officials said, providing the marsh with a dependable water source and creating new demand for the district’s reclaimed water.

“This will give the marsh a good supply of fresh water, which is very important to the marsh’s health,” Young said. “We think this presents a win-win situation.”

But some environmentalists aren’t so sure.

Their concerns center on the rich ammonia content of reclaimed water. If the water is flushed into the marsh, the ammonia could cause algae to form, said Bill Bretz, a UC Irvine zoologist who has studied the marsh.

Bretz said that a heavy buildup of algae would reduce the amount of oxygen available in the marsh water, possibly imperiling some fish.

“I don’t concur with using a natural marsh for experimental work,” Peter Bowler, a UCI biologist, said. “You don’t put reclaimed water into a freshwater marsh.”

Others, however, dismiss concerns about water quality. Young said the district will use high-quality tertiary reclaimed water that has been disinfected and filtered through granulated carbon. The tertiary water is cleaner than the urban runoff that now floods into the marsh, Young said.

“I think this is a very good idea. We should try it,” said Dick Kust, past president of Sea and Sage Audubon, a local environmental group. “The marsh and the wildlife need water. . . . I think the marsh suffers most if it doesn’t get this flow of water.”

The water district’s efforts come as the city, UC Irvine and environmentalists debate how best to heal the troubled San Joaquin Marsh, which has suffered from neglect for several decades.

The 580-acre wetlands, home to some rare birds as well as deer and bobcats, is all that remains of a giant freshwater marsh that once lined the Santa Ana River and San Diego Creek.

A consultant’s report released in 1991 suggested a $10-million to $12-million restoration plan that would focus on areas of the marsh inhabited by endangered wildlife. But the city has expressed interest in using parts of the marsh for recreational purposes.

The water district, the Irvine Co. and the UC Natural Reserve System each own a chunk of the marsh, which is located off Campus and Michelson drives near UC Irvine.

Bretz is continuing to meet with district representatives and said he might actively oppose the pumping plan if his concerns are not addressed. “We have a responsibility to protect the natural quality (of the marsh) from degradation,” he said.

No date has been set for the Regional Water Quality Control Board hearing. If the board approves the plan, the district hopes to start pumping as much as two million gallons of reclaimed water a day into the marsh in late 1994. Most of the pumping is planned for the winter months because that is when the marsh would naturally receive its supply of water.

The district has a glut of reclaimed water in the winter, in part because less water is required for farming during the season. The district plans to provide the reclaimed water free of charge during the pilot program in hope of determining whether it is cheaper to give the water away than modify reclamation operations during the winter.

Officials said the project will give scientists an opportunity to examine the way water moves through the marsh. A team of researchers from UCI and Berkeley will monitor the marsh to see what effect the water has on the habitat.

District officials hope the marsh’s plants and animals will remove the nutrients from the reclaimed water as it flows through the wetlands. In the process, the water would become cleaner by the time it exits the marsh and flows into Newport Bay, Young said.

“The marsh becomes an added treatment for the water,” Young said. “The assumption is that the water is going to be cleaner coming out than it was coming in.”