City seeks to relieve over-worked sewer plant
After a decade-long study conducted by McClure Engineering and French-Reneker-Associates revealed issues with Fairfield’s wastewater infrastructures, the city will receive $50 million in loans from the Iowa Finance Authority to improve wastewater quality.
The plan to revamp the city’s sewer system and improve its storm-water conveyance structures came after the discovery of infiltration issues hampering Fairfield’s Wastewater Treatment Plant’s ability to handle the more than 45 million gallons of water regularly flowing into it when it rained. Furthermore, the revised system would provide upgrades to the city’s sewer collection lines, which is intended to significantly reduce the overflow of sewage into its creeks.
Melanie Carlson, project engineer with French-Reneker, said the entire “sanitary sewer process is a four-step process over seven years. It replaces the largest diameter pipes in the city. They are the farthest ones downstream on the outskirts of town called interceptor sewers.”
French-Reneker is responsible for designing the pipes and storm-water conveyance systems, whereas McClure Engineering will upgrade the treatment facility.
Treatment plant upgrades will include construction of a new storm-water receiving and pumping building; a head-works building; a third oxidation ditch; a UV disinfection system and an aerobic digester.
“We are responsible for getting the sewage in the pipes to them, and they are responsible for making sure it’s clean,” Carlson said.
Additionally, the city plans to maximize the benefit of this investment by taking advantage of a new Clean Water State Revolving Fund loan program called Sponsored Projects.
With Sponsored Projects, $100,000 in accrued interest per million dollars from the $50 million loan will cycle back around leveraging approximately $5 million overall to fund community-organized water-quality strategies.
The $5 million that would have been spent on interest payments over 20 years can now be used to improve other problematic areas in the Crow and Indian Creek watersheds.
“The Sponsored Projects program gives the city an opportunity to address our storm water management issues in a creative and natural way that also takes much of the strain off the treatment plant,” said Fairfield Mayor Ed Malloy. “Understanding how to better control the flow of water from outside and inside the city along with ways to handle it more efficiently will serve our community well through these projects.”
Rain gardens and curb cutouts are just a couple of examples of how the community plans on relieving the wastewater treatment plant’s load. Rain gardens, which are usually composed of rocks and certain species of plants, work to filter rainwater and also slow the process and the volume of water, which flows into the city’s storm-drains.
“When rain falls, within 10 minutes of it hitting a parking lot, that hot, dirty water can enter into the city’s water system,” said Fairfield Sustainability Coordinator Scott Timm. He said rain gardens and curb cutouts do a great deal to filter that water.
“Instead of water running along the curb and into the drain, it would go into a curb cut out and run through a series of rocks and plants,” he said.
Timm said the city worked closely with Kum & Go Convenience Store on West Burlington Avenue during the creation of its rain garden. The garden helps filter out dirt and oil trafficked in by vehicles at the pumps.
Due to its changes, Kum & Go is now a “LEED” certified building through the national Leadership in Energy and Environmental Design organization.
A half-million dollars of Sponsored Project funds has been slated for Maharishi University of Management. MUM developed a plan to improve water runoff and infiltration on the campus.
MUM’s water club has been involved throughout the process.
“Students will continue to be involved,” said Jason Nelson, MUM water club founder. “They are excited to be working with the city of Fairfield and MUM on such a meaningful project.”