Do- It- Yourself Wetlands

Abstract

Bob Gearheart emerged as Arcata’s marsh guru during the city’s long battle with the state water bureaucracy. This unpaid post demanded that Gearheart crank out proposals for wetland treatment at a frenetic pace, knowing that the city’s financial future depended on his work. He wore a smile, energized by the pressure. Gearheart’s son, Greg, grew up to become an environmental engineer working for the state water board. He earned his engineering degree at Humboldt State, studying with his father. He remembers his dad happily engaged during the battle for Arcata’s alternative treatment system, at the same time he was teaching a full load of classes. “My dad likes a fight,” Greg says. “He adapts well. People put an obstacle in front of him, and he figures out a way to make it look like it’s not really a problem. He makes it look like it was stupid on his opponent’s part to put the obstacle there.” In 1977, the elder Gearheart proposed a first: a wetland built to treat municipal wastewater to the standards required under the Clean Water Act. He possessed a serene certainty that he could make this untried system work. “I had no data until we did the pilot study,” he remembers, “but I was one hundred percent confident.” The power of aquatic plants to cleanse polluted water had first been tested in the 1950s by Käthe Seidel, a researcher at the Max Planck Institute in Germany. She showed that while some wild plants were killed off by waters tainted with phenol—a toxic organic compound used in making plastics—others had a remarkable ability to adapt. At first contact, effluent containing phenol caused bul­rush stems to wither away, but the roots survived and in time sent up healthy new shoots. Bulrush, it turned out, could break down phenol, metabolizing it into the amino acids that build protein. The plant also thrived in domestic sewage. Seidel used carefully groomed cultures of wetland plants, rooted in beds of gravel or sand through which effluent flowed.