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Council approves preliminary sewage treatment plant plansBy Barbara Brown Presented by WSB and Associates engineer Costa Dimitracopoulos, the plan calls for a $12 million project divided into two parts. Residents who are connected to the sewer system would see an increase of about $5 per month on sewer charges to pay for the upgrade and expansion. Dimitracopoulos said his firm discovered that the current North Branch treatment plant was dangerously close to nearing capacity last spring. ìWe realized the facility is close to capacity and asked to move it up to a facility plan study,î said Dimitracopoulos. The current North Branch facility has about two more years of leeway before it reaches full capacity, Dimitracopoulos said. He said acting now will help save headaches in the future and presented four scenarios to the council for handling the situation. The council could have decided to do only limited improvements to the plant, meaning that the facility would be viable for only about two years. The third and fourth options were similar in that they called for the installation of new mechanical sewage digestion processes. The first phases of each of the methods of digestion ñ oxidation ditch or a sequencing batch reactor ñ were expected to get the city through the next eight years. The ditch method accepts waste water, deposits it into an aerated pond activated with bacteria that decomposes a majority of the waste water and passes the water onto a secondary ditch that repeats the process. Cleaner waste water is then discharged into the Sunrise River and solids are diverted to a digestor. The sequencing batch reactor performs similarly, but does the process in one contained area instead of two. During the interim, the city could begin construction of the second phase of the plant, using either method, that would make it last 20 years. The council agreed with Dimitracopoulosí suggestion to develop plans for the oxidation ditch option. Dimitracopoulos told the council that the oxidation ditch method is less technologically advanced, requires less man-power to operate and suits the cityís needs more than the one-celled sequencing batch reactor. The first phase of the ditch option would cost about $6.9 million in capital expenses and about $326,000 per year to operate. The second phase would cost about $5 million in capital, but would not add operating expenses. Dimitracopoulos said submitting the facility plan to MPCA now could mean that the city would be granted low interest loans to help pay for the plant. The loan list is compiled after April 1 each year and about 300 communities apply, Dimitracopoulos said. He said the agency then determines the need of each community before deciding which are given the loans. ©ECM Post Review |