Monday 2:30 PM
[Presentation PDF]

Room: Emerald

A Unique Approach to Aluminum and Concrete Corrosion at Cedar Rapids, Iowa, Water Pollution Control Facility

The City of Cedar Rapids is located in east central Iowa and the Water Pollution Control Facility (WPCF) treats wastewater from Cedar Rapids and surrounding communities. A heavy industrial load at the plant produces high strength waste and presents many corrosion problems throughout the plant. The aluminum geodesic domes covering the roughing filters at the WPCF were severely corroded and in various stages of failure and the interior concrete walls were also severely corroded and in need of repair. HR Green evaluated each structure and determined that high hydrogen sulfide levels and subsequent formation of sulfuric acid was the main cause of the corrosion. Several alternatives were evaluated and the recommendation was to replace the aluminum domes with a coated aluminum and patch the deteriorating concrete with mortar and coat the mortar prior to putting the roughing filters back in service. Several process changes were also evaluated to reduce the formation of sulfuric acid and help increase the life expectancy of the roughing filters and mechanical equipment. The specification was unique in its requirements for various stages of involvement from the manufacturers of the products and their qualified representatives at various milestones during the construction process.

Moderator:  Greg Garbs


Matthew J. Wildman, P.E. - HR Green, Inc.

Mr. Wildman graduated from the University of Iowa in 1998 with a Master’s degree in Environmental Engineering.  He is currently a project manager in the public wastewater group at HR Green in Cedar Rapids, IA.  Mr. Wildman spent 9 years working in Minnesota where he specialized in the design of innovative small community water and wastewater systems.  Mr. Wildman joined the HR Green Water Group in 2007.  He is a member of American Water Works Association and the Water Environment Federation.