The natural system to help with storm-water runoff that contains deicing fluids follows a series of steps the water flows through before being released. Illustrations Courtesy Ford Airport
Gerald R. Ford International Airport is taking steps to remedy a storm-water runoff issue caused by its annual use of deicing fluids.
The airport announced that it would begin construction in the fall on a $19 million natural water treatment system, which will also reroute the runoff directly to the Thornapple River.
The system will carry the storm water through a constructed biological treatment system, where vegetation beds will act similarly to kidneys, absorbing the deicing fluids and other pollutants as the storm water runs through the root system.
Additionally, the airport will continue to collect and recycle as much of the deicing fluid as possible.
The federal government will provide $13.4 million in funding for the project; the airport is spending $1.1 million. The rest of the funding will come from local and state sources.
“The Thornapple River system is a remarkable waterway that must remain clean and healthy,” said Brian Ryks, the airport’s executive director. “This new green infrastructure is a cost-effective approach to improve the airport’s environmental performance and help sustain the river’s water quality, aquatic life and natural beauty.”
The airport has been examining its storm-water runoff system since its last discharge permit was issued in 2010. At that time, the Michigan Department of Environmental Quality directed the airport to eliminate its contribution of propylene glycol to a neighboring river, known as Trout Creek, where the runoff currently enters.
The airport must be in compliance with the directive by Oct. 1, 2015, in order to receive its next storm-water discharge permit.
“Right now the majority of our storm water is discharged to the northeast, off of the airport,” Thomas Ecklund, facilities management director for the airport, previously told the Business Journal. “We have a detention basin in that vicinity and we have a controlled outlet on the detention basin. So it goes out into this unnamed tributary and works its way through a neighborhood and enters the Thornapple River.
“As a result of our deicing activity, there is a biofilm, like an algae growth, that has developed in this unnamed tributary. The permit that we have, that was issued in 2010, requires us to eliminate our contribution to the biofilm. We recognize that the biofilm is probably there because of the deicing fluid. We start deicing typically in the fall, and usually a month or so later the biofilm starts to develop. We stop deicing, and within four to six weeks the biofilm starts to break up and washes away.”
Glycol is a sugar-based substance that is eaten by naturally occurring bacteria in the tributary, which then develop into a biofilm. Residents have complained previously that its entry into Trout Creek has killed off fish and other creek wildlife, as well as emitting an unpleasant odor each spring as the biofilm dies off.
The Federal Aviation Administration requires aircraft and pavement deicing during the cold weather months. The airport has reported using an average of 80,000 gallons of glycol per year, with about a third, or 27,000 gallons, reaching Trout Creek.
“When compared to our existing system this new approach will reduce the overall amount of de-icing fluids and other pollutants going to the Thornapple River under similar winter conditions,” Ryks said. “The airport will meet and, where feasible, exceed the highest environmental protection standards.”
The airport said it worked with the nation’s preeminent glycol expert and also established an advisory committee consisting of airport neighbors, environmentalists, airline representatives, economic development leaders and others in order to develop the long-term solution.
The natural treatment system will be completed in late 2015.