Town Goes With the Low-Tech Flow

ARCATA, Calif. —  Few dream of doing great things with sewage. But fortunately for this college town, two men who saw the potential in human waste teach here at Humboldt State.

Together, Robert Gearheart and George Allen turned a local garbage dump into a low-tech treatment plant, wildlife refuge and salmon-spawning spot.

In the process, they won some respect for a town on California’s rugged north coast that was used to being derided by its neighbors for its tree-hugging, environment-loving policies.

“Both George and I are from the old school,” said the 60-year-old Gearheart, a burly sanitation engineer who now travels the world as a wetlands consultant. “We like things done relatively simply.”

In the 20 years since Gearheart and fisheries expert Allen designed the Arcata Marsh and Wildlife Sanctuary, hundreds of towns, here and abroad, have copied Arcata’s system for treating sewage. In California, the city of Davis, with 40,000 residents, is constructing its own wetlands-and-sewage system. So is Pacifica, just south of San Francisco. Phoenix is considering one.

But the marsh holds appeal for more than sanitation engineers; it has made Arcata a tourist destination. Every year, about 150,000 people flock to this town of 17,000 to visit the 154-acre refuge.

Birders and eco-tourists come to observe the thousands of migrating birds that rest and feed here in the spring and fall. The Audubon Society gives weekend walking tours. Delegations of engineers and municipal politicians from around the world come to copy the system for their own towns.

The tourists often don’t realize that the sanctuary’s paths lead them through part of Arcata’s sewage treatment plant. The tanks that collect the sewage of Arcata’s 17,000 residents and separate solids from water are tucked out of sight. There is no smell of raw sewage on the series of ponds the waste water flows through before it is discharged into Humboldt Bay.

“We’ve shown that human waste is not just something to be gotten rid of,” said Gearheart.

With its meandering trails, wild blackberry bushes, picnic areas and fishing holes, the marsh also is a favorite haunt for locals, who jog and stroll here year-round.

Just minutes from downtown Arcata, herons, snowy egrets, pelicans and clapper rails hunt the marsh’s chain of ponds. Swallows dart through the air, chasing mosquitoes. Clumps of bulrushes, waving in the breeze, shelter nests.

Few visitors are aware that the plants draw bacteria and other toxins out of the ponds in which they grow. Filter-feeding organisms in the marsh water eat the microbes that attach to the plants’ roots and stems. The ponds, essentially, serve as a giant filtration system, cleansing the water before it goes into the bay. The system needs neither the massive infrastructure nor heavy chemical treatment used to remove bacteria in more traditional sewage plants.

But it does need two things many large urban communities don’t have--a lot of space to build marshes big enough to process the sewage, and the absence of heavy metals produced by industry, because a marsh cannot process them. Arcata has no heavy industry.

The marsh’s success has made Arcatans feel good about themselves. The only town in America governed by the Green Party, Arcata often finds itself the butt of jokes from nearby towns like Eureka and McKinleyville for being a bastion of hippiedom, a place passionately committed to recycling, vegetarian restaurants and natural-fiber clothing boutiques.

“You have got to take risks now and then,” said Mark Andre, Arcata’s deputy director of environmental services. “Sometimes you fall on your face and other times, you look good.”

And the project has saved money. Its $5.3-million price tag was less than half of what would have been Arcata’s proposed share of a high-tech regional treatment plan. Residents’ sewage bills in Arcata are the lowest in the county.

Back in 1977, when Arcata proposed building the marsh, the town met with stiff opposition from the state Water Resources Control Board and outrage from neighboring towns. No American town had ever proposed treating its sewage in a marsh. The board argued that Arcata would never meet federal clean water standards unless it treated sewage with chemicals.

At the time, towns ringing Humboldt Bay--including Arcata--had antiquated sewage systems that were dumping raw sewage into the bay.

The largest estuary between San Francisco Bay and the Columbia River, Humboldt Bay is particularly sensitive to water pollution, because two-thirds of the state’s Pacific oysters grow in beds on its north side, where Arcata lies. For years, contamination from the region’s sewage treatment plants regularly forced shutdowns of the oyster beds.

“If you dump a glob of blue paint where Arcata discharges its water into the bay, within an hour that has spread over the oyster beds,” said William Rodriguez, a sanitary engineer with the water control board’s north coast regional district who originally opposed the Arcata plan.

To comply with new federal pollution standards, the board planned to build a gigantic high-tech plant that would treat the sewage of 10 towns and discharge it into the ocean. But the board ran into a buzz saw of opposition from Arcatans, who didn’t like the $56-million price tag and feared the plan would spur unwanted commercial and residential development.

Gearheart and Allen seized on a loophole in the federal Clean Water Act that said communities could not discharge into bays or waterways unless the effluent “enhanced” the quality of the bay’s water. Their proposed low-cost, low-tech sewage treatment system, they said, would enhance Humboldt Bay and allow Arcata to turn its back on the regional plant.

By 1977, Allen had been raising coho salmon in Arcata’s old sewage plant’s oxidation ponds for nearly a decade. He had found in 1971 that the salmon grew well in a mixture of treated sewage water and brackish bay water. The water was so rich in nutrients that there was no need to feed the fish commercial food.

Funded by the city of Arcata, Allen built a laboratory and released his fingerlings into the bay from the ponds. Year after year, the fish returned to spawn in their sewage-fed birthplace.

Reluctantly, after months of debate, the water board agreed to let Gearheart and Allen test a plan that relied more on nature than engineering to process sewage.

The system Gearheart designed--opened in 1985--is indeed a simple one.

Sewage flows into the collection area, where waste water is separated from sludge. The sludge is kept in huge tanks, where it is “digested” for a month before being drained into drying trays. The dried sludge then is broken up and mixed with plants harvested from the marsh and wood chips in a compost pile. High temperatures in the pile kill off harmful bacteria. Within a month, the compost is ready to spread across the town’s soccer fields, its forest and on flower beds.

The water, meanwhile, sits in an oxidation pond, where sunlight kills most microbes. It is chlorinated, then allowed to flow into a series of three marsh ponds. There, it mixes with the brackish water of the bay. Two weeks to a month after it first enters the plant, the water is rechlorinated, then dechlorinated and discharged into Humboldt Bay.

Strolling through the marsh on a fall day with Allen, now retired but still sprightly at 75, it is hard to imagine that two decades ago, the birth of this peaceful place was preceded by battles so bitter they are known in Humboldt County as “the Waste Water Wars.”

“There has been a remarkable improvement in the water quality of the bay,” since Arcata’s plant began functioning, water engineer Rodriguez said. “Rarely do they have an impact on the oyster beds anymore. I think their plant is doing a very good job.”

After Arcata pulled out of the plan to build a regional plant, that proposal was abandoned. Eureka built its own high-tech facility on the south end of the bay, which discharges only on the outgoing tide. McKinleyville built a plant that discharges into the Mad River.

Allen and Gearheart say the marsh battle was really about common sense, about using what is at hand and getting the most out of resources.

Both men are slightly embarrassed by the local-hero status they have as founders of the marsh.

One of the sanitation ponds has been named in Allen’s honor. Another has been named for Gearheart.

“Sort of makes me feel I have an obligation to be cremated and have my ashes scattered across it,” Gearheart said with a laugh.