Dec 11, 2007

Michigan Township Plans Treatment Plant Upgrade

Two-phase project would replace old building section, equipment

Officials in Ann Arbor Township, Mich., have proposed that a sewage treatment plant site be zoned as a recreation and conservation area. The plant, near the Huron River, is scheduled to receive $100 million in improvements; construction cannot begin, however, because township laws prohibit major renovations on land parcels listed as nonconforming, such as the plant site's.Ann Arbor Township leaders are uncertain how the site was assigned its current categorization and plan to rezone the parcel to public lands. "It's probably just historical," said Clerk Rena Basch. The treatment plant's first phase of construction dates back to the 1930s.The design for the first part of the plant improvement project is complete and involves installing new technology to replace waste solids thickening equipment, according to Earl Kenzie, manager of wastewater treatment services. The plan also addresses odor control and truck loading and chemical loading facility issues, Kenzie added.It is hoped construction will begin in spring 2008 and be completed in about 18 months. The first improvements phase will cost an estimated $35 million.The second part of the project will involve demolishing and replacing the plant's western section, which was built in the 1930s and is no longer used, Kenzie said. He expects this phase will begin at least one year after the first phase is finished, take five years to complete and cost $70 million. Sewer revenue bonds would cover costs for both phases, according to Kenzie.Ann Arbor Township's wastewater treatment plant currently handles about 19 million gal per day (mgd), and while the renovations will not increase its 29.5-mgd average capacity, average handling numbers are expected to increase in the coming years. "[The renovations are] to allow us to reliably handle the capacity we're permitted right now," Kenzie said.