NATCHEZ — Natchez Water Works has received its second award for the solar-powered greenhouse system at the Natchez Wastewater Treatment Plant that turns sewage sludge into organic fertilizer.

The Mississippi chapter of the American Council of Engineering Companies honored Water Works at the group’s annual award ceremony earlier this month in Jackson for engineering projects that are “original, innovative and provide technical and economic value.”

The plant upgrades during the project, which began in early 2010 and wrapped up in 2011, included the construction of the greenhouse and the installation of a mechanical filter system the sludge passes through.

The greenhouse also has a computer system that can manipulate weather conditions to speed up the biosolid’s drying process.

The system takes household sewage from sinks and toilets and treats it through a natural process. The water is separated from the sludge and made clean enough to pump into the Mississippi River through a gravity flow piping system.

The result is a dirt-like biosolid that, when confirmed grade-A by the Mississippi Department of Environmental Quality, can be used and even sold as organic fertilizer.

Judy Adams, head of the ACEC Mississippi chapter, said in a press release the project was original because it uses solar energy and automation.

“And this project will save taxpayer money,” she said.

Natchez City Engineer David Gardner said the city could not only profit from the sale of the fertilizer, but he said it is also saving money by not spending an average of $200,000 each year to remove the sludge from the plant.

Gardner said he was very pleased to receive the award and proud of the project’s engineers, engineering department and Water Works staff teamwork and collaboration on the project.

“And I am also thankful to the water board for allowing me to take on such an innovative project,” he said. “It was brave on the board’s part, and I appreciate their confidence.

The project’s engineering company, WGK Inc., of Clinton, was awarded ACEC’s Grand Conceptor Award for the design of the upgrades to the plant.

Water Works also received an award from the Mississippi Development Authority’s Energy Division in October for the fertilizer project. Gardner said the award was in recognition of energy reduction and technology used for the program.

Gardner said he believes the project, the first of its kind in Mississippi and one of only two in the state, has given the community a sense of pride as forerunners in innovative technology that created a new, environmentally sound and energy-saving system of handling sludge.

“We’re very proud of this project,” he said. “I think we can set a good example for the rest of the state. I wish we had it 20 years ago.”