Water pollution control plant to see $5.8M in improvements

Three years after City of Newton staff identified needed improvements to the water pollution control plant and its southwest pump station, the council on Oct. 24 awarded a more than $5.8 million contract to Fort Dodge-based contractor Woodruff, LLC to make the improvements.

Planned improvements at the plant include: a one million-gallon liquid sludge storage tank, new standby power generator, rehabilitation of three existing floating steel digester covers, the replacement of two sludge pumps, new influent channel mixing system, the replacement of plant PLCs and other work items.

Improvements for the southwest pump station include: the replacement of both 150-horsepower pumps with new 200-horsepower pumps and replacement of the pump station interior dry well piping, as well as associated site, demolition, electrical, mechanical and other associated work items.

Newton Public Works Director Jody Rhone said one of the major components to the project is the backup generator for the entire plant. For many years, staff have used a dual power supply, but Rhone said that is no longer permissible to have those feeds, for fear of electrical backfeeding through Alliant Energy.

Iowa Department of Natural Resources also requires wastewater plants to have a backup generator. As staff found out during the 2020 derecho, if the transmission lines are down the plant has no power. Rhone said that can cause bypassing, which is a violation of the city’s discharge permits.

The project came in under the engineer’s estimate of $6.3 million. In addition to Woodruff’s winning low bid, Amana-based contractor WRH, Inc. bid $6.19 million for the project. To pay for the project, the city is using more than $4.9 million from the plant’s 2021 bond revenues and more than $970,000 in future revenues.

There are no general fund dollars going into this project.

All sanitary sewer sewage in Newton is treated at the water pollution control plant. Everything that goes down a citizen’s drain — whether it is a toilet, sink or floor drain — ends up at the plant, is cleaned up and environmentally discharged into Cardinal Creek. There are 96 miles of sanitary sewer lines around Newton.

Contact Christopher Braunschweig at 641-792-3121 ext 560 or at cbraunschweig@newtondailynews.com