In April 2007, the Village of Verdigre, Nebraska was faced with drastic changes to their wastewater treatment plant NPDES permit. Along with these changes, all of the engineering planning that was completed to this point was not usable to address the changes in the treatment plant. WLA was retained to develop a facility plan, complete final design to address the new permit limitations and provide assistance with regulatory and funding coordination. New ammonia limits for year-round discharges were being proposed by the NDEQ that included a summer effluent limit of 0.64 mg/L, and limits for spring and winter. In addition to ammonia, continuous disinfection of the effluent would be required. The receiving stream, Verdigre Creek, is classified as a Class “A” stream, which is capable of supporting trout fish species.
WLA prepared the facility plan and proposed a treatment process that will meet all of the new effluent limitations. The facility plan included significant upgrades to the existing mechanical wastewater treatment plant. However, due to a series of challenges in available funding for an upgraded mechanical facility, further wastewater treatment alternatives were considered. An updated facility plan was developed which evaluated several treatment options. Alternatives evaluated included a packaged SBR mechanical plant, complete retention lagoons east and west of the village, modified controlled discharge lagoon, and a land treatment storage lagoon. Capital cost estimates, operation and maintenance costs, replacement costs and life cycle costs were developed for each treatment alternative. The Village decided to proceed with a complete retention lagoon west of Verdigre. This option will address the pending NPDES permit by having no-effluent discharge to Verdigre Creek. The complete retention lagoon also provided for greater funding assistance for the Village of Verdigre.
Project costs are estimated at $2,315,000. Coordination with the NDEQ, Nebraska Department of Natural Resources, USDA Rural Development, and the Water/Wastewater Advisory Committee, WLA has successfully received approval for the facility plan and procured grant funding of $100,000 from the NDEQ Small Town Fund and $250,000 from the Community Block Development Program. Additionally, the USDA Rural Development will fund the balance of the project in federal loans and grants. WLA completed final design in December 2009 and construction was completed in late 2010.