South Carolina City Lets Nature Treat Its Sewage : Environment: Solar heat and bacteria purify the water. Plants, wildlife thrive on the nutrients. Designers say it costs less than conventional systems.

This coastal city has a sewage disposal system that dumps 450,000 gallons of waste water a day into wetlands.

And environmentalists could not be happier.

“The wetlands work like a kidney, removing the toxins while the plants take in nutrients from the waste water,” said Donna Gress of the South Carolina Coastal Council.

Plants and wildlife that receive waste water from the Grand Strand Water and Sewer Authority appear to be surviving and even thriving.

The wetlands disposal area, capable of handling up to 2.5 million gallons a day, is expected to solve the area’s sewage problems for at least 25 years.

The system purifies water by relying on solar heat and bacteria.

It cost about $7.5 million, or one-third to one-quarter the price of a treatment plant of the sort used by most cities, according to the project’s designers.

The system could help booming coastal cities struggling to find relief for the sewage disposal headaches that come with population growth in low-lying areas.

Plans already are in the works to build similar plants in Beaufort and on Hilton Head Island.

“We are very excited about this project,” said Ron Tata of the South Carolina Department of Health and Environmental Control. “It’s replenishing the ground water and taking advantage of nature to solve our problems. It’s definitely better than using chemicals and energy-intensive ways to treat human waste.”

Tom Welborn, chief of the wetlands regulatory unit for the Environmental Protection Agency, said similar systems probably will be built across the country in the next decade.

“Pumping waste water into the site up there (in Horry County) actually improved the wetlands, making it function better biologically,” Welborn said. “It’s a win for the environment as well as a win for sewage treatment.”

In the nine months since the plant first went into full operation, “We’ve found no problems whatsoever with the project.”