By Marty Mulcahy
ANN ARBOR - Out of sight, out of mind.
That's been the typical attitude by community leaders across the nation as they consider replacement or rehabilitation of their aging water and sewer systems.
Ann Arbor, however, is staying on top of past, present and future issues with their sewer system, as they near the end of a multi-year, $100-million-plus upgrade project at their Wastewater Treatment Plant at Huron River Drive and Dixboro Road. It's one of the largest capital improvement projects in Ann Arbor's history.
The ongoing work, led by Walsh Construction, stems from a Facilities Master Plan completed by the city in 2004 that identified a long list of improvements needed at the plant "to meet future flow and loading demands as well as regulatory requirements. The required renovations to the aging and deteriorating plant include rehabilitation of existing structures, upgrading of primary and secondary wastewater treatment processes, and replacement of aging facilities with new facilities," says a review of the project by the City of Ann Arbor.
Work at the plant began in 2011 and will wrap up next year. The current plant serves a population of about 130,000 and has a design capacity of 29.5 million gallons per day, but takes in an average of nearly 19 million gallons of wastewater per day from the cities of Ann Arbor and Pittsfield, and Scio and Ann Arbor townships.
Prior to this project, the plant consisted of an older West Plant (constructed in the 1930s), and a newer East Plant (constructed in the 1970s). Renovation work was divided into Phase I and Phase II.
Phase I included relocation of utilities, demolition of the plant's storage building and aeration tank, and installation of a waste activated sludge line to convey sludge to the solids handling building.
Phase II has been much more intensive, and includes a laundry list of projects with attention to fixtures unique to the sewage handling industry. In addition to significant West Plant demolition and reconstruction, work on that side has included the design and construction of: primary and secondary clarifiers, a new administration building, an influent splitter/flow monitoring station, aeration tanks, and a stormwater pumping and discharge facility.
On the East side, there have been modifications to the electrical/blower building including removal of the standby generators and electrical gear, and installation of a new wastewater sampler room within this building and replacement of the East return activated sludge pumps. The project has also included electrical improvements to the East Plant's primary building, miscellaneous repairs to the secondary clarifiers, conversion and rehabilitation of the dechlorination building, and replacement of old below ground boiler piping.
"I have been out here four years," said piping contractor DeCal's general foreman Bill Schroeder. "And yeah, there's the smell, and I guess you're rather be in a fresh water treatment plant, but you'd be surprised, a lot of the equipment is the same. There's such a variety of piping and mechanical systems. We've had our share of challenges, but overall it's been a good job."
There has been a whole lot more on the to-do list at the plant that we don't have space to mention. Over the years, the project has moved 1,262 Hardhats through the safety orientation process, making it a significant employer.
"Through this whole process, I think we can be proud that this facility has been kept up and running the entire time," Schroeder said. "That says a lot about what we have been able to do. I mean, you can't shut it down, you can't send an email to all of Ann Arbor's residents and tell them not to flush" while there's an equipment changeover or new pipes or fixtures are brought on line.
Mike Amicangelo, senior utilities engineer at the plant, told the Ann Arbor News that there are a number of site limitations that prevent the plant from being able to expand beyond its existing footprint, as it's bordered to the north by the Norfolk Southern Railroad, to the west and south by the Huron River, and to the east by Fleming Creek. "Everything we do within the facility — every upgrade, every equipment replacement — has to be done within that footprint," he said. "The site's fully utilized."
Another four-year veteran at the plant is Motor City Electric/Huron Valley Electric general foreman Joe Piliszko, who said the variety of electrical applications at the site rivaled that of the plumbing fixtures. "Definitely not your typical project here," he said, "and it's been a huge learning experience not only for myself but for everybody here."
He pointed out there was conventional electrical systems in the newly erected administration building, and the rest of the plant had a variety of electrical applications as well. Low to medium voltage systems have been installed with related splices and terminations, with wire moving through galvanized rigid pipe, PVC, all the way up to large duct banks.
"Just a big variety of stuff going in; an interesting job," Piliszko said. "It's been good to be here, it's a good job, you even get used to the smell after a while."
WORKING ON CONDUIT INSTALLATION in one of the east aeration tanks at the Ann Arbor Wastewater Treatment Plant are IBEW Local 252 electricians Joe Piliszko (general foreman), Ernie Fargo and Kevin Granger (on the lift). They’re employed by Motor City Electric/Huron Valley Electric. The sewage facility’s solids handling building is in the background, and Joe gave us a laugh when he commented that, “It’s not as glamorous as it sounds.”
SETTING A NEW 60-INCH concrete-lined steel intake pipe at the Ann Arbor Wastewater Treatment plant are (l-r) Gideon Miller (Plumbers and Pipe Fitters Local 190) and Jay Flowers (Plumbers 98). They’re employed by DeCal.