New Sewage Plant Nearly Ready to Go on Line in South County

The first phase in the construction of a new sewage treatment plant to help serve the growing population in south Orange County is nearing completion in what was an untouched canyon, except for the meanderings of cattle, deer, hawks and an occasional horseman.

Sometime this fall, sewage will begin flowing through eight miles of pipe that lead from huge housing developments springing up in the foothills of the Santa Ana Mountains to the plant in Chiquita Canyon, about 1 1/2 miles northeast of the San Juan Capistrano city limits.

After treatment for removal of sludge and the addition of chemicals, the effluent will move through another eight-mile-long pipeline to the ocean outfall at Dana Point.

“Wherever you have great numbers of new homes and businesses being built, you have to have new plants like this,” said Bill Knitz, general manager of the Santa Margarita Water District, which is building the project.

Initial construction consists of digesters, trickling filters, clarifiers, a laboratory and office buildings at a cost of $18.5 million, Knitz said. The plant in its first phase will be capable of handling up to 3 million gallons of effluent per day, he said.

The 16 miles of pipes, some up to 38 inches in diameter and some running very close to downtown San Juan Capistrano, already are in place and cost an additional $18 million.

“We hope to start the second phase early in 1987,” Knitz said. “It’ll be needed because home development is going so fast in the foothills.”

The second phase, he said, will add an additional 3 million gallons per day to the plant’s capacity. Its cost will be “something under $6 million,” far less than the first phase, which included extensive grading and the construction of access roads and storm drains.

A third phase, of about the same cost and capacity as the second, probably is several years off.

The roads, drains and other facilities for the first phase were built by the Fluor Corp. at a cost of $1.6 million, a figure that was included in the $18.5-million total.

Knitz said the plant itself covers 25.5 acres, but the water district owns a total of 85 acres in the picturesque canyon, which was part of Rancho Mission Viejo.

“Our property extends up to the ridgelines on both sides of the canyon,” he said, “so no homes will ever be built looking down on the plant.”

To Supply Electricity

Don Roberson, contract administrator for the builder, MacDonald Stephens Engineers Inc. of Laguna Hills, said the plant will supply its own electrical power when completed.

“Methane gas taken from raw sewage in the digesters will be stored in a 37-foot-high steel sphere, with a capacity of 22,500 square feet, and used to produce electricity,” he said.

Roberson said that noise and odor problems will have little impact in the remote canyon and that the effect on wildlife has been minimal.

“In spite of all the building activity and heavy machinery, we see lots of deer, coyotes, rabbits and ground squirrels,” he said. “In fact, we watch hawks catch rabbits and squirrels and carry them up to the top of some of our tanks to have lunch without being disturbed by coyotes. They’re not so dumb.”

He said the eight-mile pipeline from the plant to the ocean outfall will be tested for leaks during the next few weeks.

Reclamation Comes Later

The project’s official name is Santa Margarita Water Reclamation Plant, but Knitz said no water will be reclaimed during early operations.

“Eventually we hope to be able to reclaim some, probably for agricultural use in and near the canyon,” he said.

Initially, the plant will serve the 20,000 or so homes and businesses being built at Rancho Santa Margarita, plus those at the exclusive Coto de Caza development.

As the plant is expanded, hookups will be made for such other large foothill developments as the Robinson Ranch, Portola Hills and others, Knitz said, offering service to about 80,000 people.

The additional millions of gallons of effluent reaching the Dana Point ocean outfall should be absorbed easily by that facility.

Bill Sukenik, general manager of the South East Regional Reclamation Authority (SERRA), which operates the line, said the outfall has a potential peak flow of 63 million gallons per day and currently is handling only 12 million to 13 million gallons daily from such communities as San Clemente, Dana Point, Capistrano Beach, San Juan Capistrano and Mission Viejo.

Selection of the site in Chiquita Canyon came in September of 1984 after months of controversy and complaints from residents of Mission Viejo and San Juan Capistrano who expressed concern that a location would be chosen that would adversely affect their neighborhoods with noise and odors.

Fourteen possible sites in southern Orange County were under consideration. When the remote Chiquita Canyon site was chosen by the Santa Margarita Water District’s board of directors, all parties approved.