Plan for Bird Haven Not Hard to Swallow : Nature: Head of Valley sewage treatment plant readily agreed to accommodate the avians that made Capistrano famous.

Just when it seems that city government is for the birds, along comes a bureaucrat who proves it.

Imagine Robert W. Birk earlier this year, minding his own business as the San Fernando Valley’s prince of sewage processing.

He’s got his head buried in budget documents. He’s trying to explain Total Quality Management to his electricians. He’s studying aeration optimization techniques. Basically, he wants to make the Donald C. Tillman Water Reclamation Plant the most efficient refiner of effluent in the state.

And then along comes some guy who suggests that he also make it a swell place for swallows.

Did Birk quail? He did not.

In an attempt to give Mission San Juan Capistrano a run for its tourist money, Birk authorized his engineers to make the Tillman plant a haven for Hirundo pyrrhonota-- the common cliff swallow that a saccharine song back in 1939 turned into a tourist draw for the little town on the Orange County coast.

And so far, he’s got no . . . umm . . . egrets.

“Actually,” he says, “the swallows had already adopted this place. We’re just doing something to encourage them to return.”

The birds started arriving at the sewage plant about four years ago, said Tillman docent Allan E. Edwards, just as the numbers that actually do return to Capistrano each March began to thin.

It’s not hard to figure out why.

Tillman is surrounded by a lovely, green-colored lake and Japanese garden that buzz with the mosquitoes, gnats and dragonflies that the swallows crave. The swallows prefer to nest as close as possible to their food source and, although the mission in Orange County has undergone a dusty and noisy reconstruction recently, the Tillman plant offers solid concrete in just the right place.

The 20-foot-high concrete eaves of its administration building soar just a few hundred yards from the natural banks of the Los Angeles River, which provide mud for the swallows to use in building gourd-shaped homes about the size of a human head.

Today, those eaves offer cool corners for the nests of hundreds of swallow families. Visitors can crane their necks to view tiny, chirping chicks sticking their beaks out to snap up a snack from their darting, singing parents.

Birk’s contribution to the natural order: He had workers install metal mesh over those eaves that shelter the building’s walkways. Barred from nesting in those spots, where their wastes would become airborne bombs, the swallows are free to come and go as they please without the threat of being shooed toward less hospitable climes.

“Swallows will go anywhere they can find mud and no one will bother them,” said Irene Langton, a bird-identification officer in the San Fernando Valley Audubon Society. “People love them so long as they’re not nesting over their doorways.”

Langton occasionally has to instruct people who do complain about their messy habits that the creatures are protected by the federal Migratory Bird Treaty Act. To kill a swallow or destroy an occupied nest is a misdemeanor carrying a penalty of a $500 fine or six months in jail.

Such landlocked concerns don’t seem to bother the birds. They are going places. Soon, perhaps in mid-August, the swallows will end their mating season in the Valley and wing toward Argentina.

When they return, will the city plan a parade to rival the one in San Juan Capistrano, ring church bells, declare a civic holiday? Maybe not.

“They kind of straggle in,” said Birk. “But they seem to know the welcome mat is always out.”