Iowa City celebrated the completion of upgrades to a wastewater treatment plant, whose long journey to completion endured droughts and floods.

The revamped South facility, 4366 Napoleon St. S.E., is now the only wastewater-treatment facility for the city.

Wastewater Superintendent Dave Elias said conceptual work for the facility began in 1975, and Iowa City Mayor Matt Hayek said it was the culmination of seven major projects.

Costing $50.1 million, it is the largest public-works project Iowa City has ever undertaken. 

The U.S. Department of Commerce Economic Development Authority provided $22 million to the construction of the new plant.  Two state sources, I-JOBS and a grant from the Iowa Economic Development Authority, gave $19.3 million.  A local-option sales tax, voted in by the city, and city wastewater revenues are responsible for the remaining $8.8 million.

The nearly total destruction of the former North wastewater-treatment plant, 1000 S. Clinton St., in the 2008 flood increased the urgency of the project.

Hayek said the new facility can process up to 24 million gallons of water a day, or up to 43 million during adverse conditions.  These increased capabilities are especially important for Iowa City as it continues to grow.

“This new facility, for the first time in decades, allows us the possibility of significant population expansion,” Hayek said.

However, Hayek said there is still more work to do on some of the smaller aspects of the system as some sewer lines date back to the 19th century.

Environmental and financial sustainability is another cornerstone of the new facility’s mission.

The plant will recycle water and use it for, among other things, the watering of the nearby community soccer field. It also produces enough fertilizer to cover more than 800 acres of land, and reclamation of methane from wastewater may save the city $50,000 annually, Hayek said.

The evolution of the technology used to treat the water is part of the plants environmentally conscious model.

Ultra-violet rays, like those from the sun, have replaced chlorine gas and sulfur-dioxide as the filtering media, Elias said.

Elias said the most important part of abandoning chlorine and sulfur-dioxide was the increased safety of both the community and wastewater workers.  The chemicals, he said, if accidentally mishandled, could have forced an evacuation of the five miles surrounding the plant and an unknown degree of environmental damage.

“It’s a more efficient facility than we had before, and I’m glad it’s up and running,” Iowa City City Councilor Kingsley Botchway II said.

Hayek said in place of the old North facility, the city is planning to design a city park, which will be one of the “bookends” for the Riverfront Crossing District. 

The park will help expand the flood capacity of the area.  Additionally, according to the proposal of the project, removal of the plant ensures there is no risk of commercial and residential exposure to untreated effluent in that area during future floods.

“We’re not having a ribbon cutting; we’re opening the floodgates,” Elias said.