Columbia continues federal water monitoring program
The wells rise from the ground like metal trees, pumping water from an underground store for further treatment. A drive south on Route K takes you through the flat land, dotted with an occasional silo, the wells used to collect drinking water for people in Columbia.
Just north of it lies the Eagle Bluffs Conservation Wetlands, owned by the state. The city contributes to the more than 4,000 acres with what it calls “recycled water” from its sewage treatment facility on Gillespie Bridge Road. After removing some of the solids and treating it with various chemicals, it sends the treated sewage to the wetlands.
With the two bodies of water so close to one another, Assistant Utilities Director David Sorrell said the department wants to ensure none of the treated sewage effluent finds its way into the drinking water supply. The city council approved a $57,160 contract with the USGS to continue monitoring the ground and surface water in and near the wetlands – a relationship started in 1992.
“Insurance,” Sorrell called it, “for us to ensure that we’re protecting the health of our whole community by not contaminating out drinking water supply.”
Columbia began sending its treated sewage water to the wetlands in 1994, with federal monitoring starting two years prior. The USGS agreement said groundwater chemistry changes in the area due to the treated sewage discharges, and testing will help the city know what chemicals or compounds exist in it, and if any are flowing into the drinking water supply, known as the McBaine Bottoms. Sorrell said the city has not had dangerous levels of sewage effluent since testing began.
“If some significant change were to occur, then that would tell us we need to plan to make modifications to our operations.”
The USGS said it would test for inorganic compounds at twelve monitoring wells two times a year, and test for organics one time. The fiscal year 2016 agreement features two new monitoring wells, drilled deeper to the aquifer, which Sorrell said sits 110 feet beneath the surface.
