Cleanup Team : The Audubon Society and Tillman reclamation plant will join forces for Earth Day, inviting the public to pick up litter, watch birds and take garden tours.

You might think the Audubon Society--one of the first environmental organizations in the United States--and the Tillman Water Reclamation Plant--the city-operated facility that processes the stuff that San Fernando Valley residents run down their drains and flush down their toilets--wouldn’t have much to do with each other.

You would be wrong.

The Audubon Society and the Tillman Plant are getting together to throw an Earth Day celebration and cleanup from 8 a.m. to noon Saturday at the Sepulveda Basin Wildlife Area in Van Nuys. The agenda for the day includes picking up litter--which will be recycled or composted as much as possible--along the paths, followed by bird-watching, nature walks and tours of the Japanese Garden and Tillman plant.

“It is a great opportunity for the public to learn, to help take care of this wonderful nature area, and make a difference in their environment,” said Muriel Kotin, president of the San Fernando Valley chapter of the Audubon Society.

Beginning at 10 a.m., easy, one-mile bird-watching walks through the wildlife reserve will be led by Audubon Society volunteers.

According to Kotin, waterfowl such as herons and egrets are likely to be spotted in the lake, and orioles, blue grosbeaks and red-winged blackbirds will probably be singing from the trees.

Those who can’t bring binoculars can borrow them, and bird-watchers must be at least 8 years old, Kotin said. Sunscreen, broad-rimmed hats, gardening gloves and sturdy shoes are suggested for participating in the cleanup and nature walks.

One-hour tours of the Tillman Water Reclamation Plant will begin at 10 a.m. for anyone at least 12 years old. Treated waste water from the Tillman Plant--which filters, chlorinates and dechlorinates more than 40 million gallons of raw sewage every day--is used to fill the lakes and irrigate the wildlife area.

Docents also will lead tours through the Japanese Garden next to the Tillman plant. Fashioned after 18th-Century Japanese estates, the 6.5 acres are composed of three distinct areas--a dry, Zen garden with stone and gravel arrangements, bonsai and a wisteria arbor; a strolling garden with waterfalls, lakes, streams, bridges and hand-carved stone lanterns, and a tea garden, including a teahouse.

Azaleas, willows, magnolias, cherry trees, iris and lotus are planted in the garden, and reclaimed water treated at the Tillman Plant is used for irrigation and to create the lakes, streams and waterfalls.

“We want the public to make the connection between reclaimed water, the beautiful garden and wilderness lake,” said Lynne Goldsmith, a spokeswoman for the city’s waste-water program. “Treated water can be safely reused for people’s enjoyment, to create beautiful areas and to benefit the environment.”

Where and When

What: Earth Day Celebration and Cleanup.

Location: Sepulveda Basin Wildlife Area, 17015 Burbank Blvd., Van Nuys. Park in lots off Woodley Avenue, north of Burbank Boulevard.

Hours: Cleanup 8 a.m. to noon Saturday, bird-watching and nature walk, 10 a.m. to noon. Tillman Water Reclamation Plant and Japanese Garden tours, every half-hour from 10 a.m. to 11:30 a.m.

Who’s invited: Anyone at least 8 years old for cleanup and bird-watching nature walks; 12 years and older for Tillman plant and Japanese Garden tours.

Call: (818) 783-4293 for nature walks, cleanup or bird-watching; (213) 847-9508 for Tillman plant and Japanese Garden tours.