The Moving Bed Biofilm Reactor (MBBR) is filled with plastic media during construction. It will remove nitrogen during wastewater treatment.
Village of Birchwood officials knew they had a big problem. Their aging wastewater treatment facility could not meet state-imposed nitrogen limits and expected improvements were going to cost millions of dollars. To add to the challenge, the facility serves a population of 435 individuals and local businesses, and there were tight site constraints.
MSA worked with the Village to identify wastewater treatment needs and then evaluated solutions in the facility planning stage. The existing aerated lagoons had sludge build-up that reduced the holding time for treatment and the 30-year-old aeration system was inefficient. The existing system facilities were not capable of meeting new regulatory requirements and several of the lift stations in the collection system were obsolete.
The Village Board approved the following Facility Plan recommendations:
MSA’s wastewater team recommended installation of a moving bed biofilm reactor (MBBR) for nitrogen removal, one of the first times this system has been used for this purpose in Wisconsin.
- Replace Lift Stations 2 and 4; retrofit Lift Station 3
- Add influent fine screening and upgrade the aerated lagoons
- Add a treatment process for nitrogen removal
This system is well suited for Wisconsin’s cold winters and can be installed on a small site.
The total project cost for Birchwood’s wastewater treatment facility and lift station project was $4.7 million. With MSA’s help, the community obtained $3.9 million in grants to pay for 83% of the cost
. Funding sources included the following:
- Community Development Block Grant: $500,000
- Wisconsin Department of Natural Resources (WDNR) Clean Water Fund Principal Forgiveness (Grant): $500,000
- WDNR Clean Water Fund Hardship Program Grant: $2,937,544
- WDNR Clean Water Fund Hardship Program Loan (0% interest, 20-year term): $758,947