Aging Sewer Lines Cause Traffic Backups And Sewage Spills
By Beth Milligan | June 16, 2020
Aging infrastructure continues to pose challenges in northern Michigan, with East Bay and Acme townships faced with traffic backups as crews tackle a million-dollar-plus sewer repair project and Traverse City plagued with sewage backups as its own decades-old pipes are inundated with rising waters and hard rains.
East Bay and Acme townships are funding a joint project to reconstruct a half mile of sewer line on US-31 between Three Mile and Four Mile roads. The total project cost is just over $1 million, with Acme funding 51.2 percent and East Bay funding 48.8 percent based on the townships’ mutual sewage agreement. The 42-year-old sanitary sewage pipeline – which at one time accepted all of Acme Township’s sewage and about half of East Bay Township’s – carries nearly 400,000 gallons of sewage flow daily. The force main sewer is seven feet below the road and just feet from East Grand Traverse Bay.
“A break in this line could be catastrophic to the users of the system and to the great water resources that draw residents and visitors to live, work, and play here,” the townships said in a joint release Monday with project partners Wade Trim and Insituform. “Preventing a failure on this line is paramount.”
The deteriorating pipe is being reconstructed through a process called cured-in-place pipe (CIPP), a “trenchless” technology – meaning the old pipe doesn’t have to be dug up and replaced. Instead, a felt lining is inserted into the damaged pipe and exposed to hot water or steam that causes it to attach to the inner walls of the pipe – forming a new jointless, seamless inner pipe. This sealed “pipe within a pipe” keeps external water and tree and plant roots from infiltrating the system – factors that often contribute to sewer overflows. Insituform, considered an industry leader in installing CIPP, has been hired to complete the work.
The project began four weeks ago on the north side of US-31 at Four Mile Road, causing lane closures and considerable traffic backups in the corridor. Starting next week, work will migrate to the south side of US-31 and head west. The southern eastbound lane of US-31 has been closed at the location and will remain so for at least another month, with work slated for completion at the end of July. Traffic delays have prompted drivers to flood social media with complaints and questions about the project, including confusion about why the sewer work didn’t take place in 2015 when the US-31 corridor was reconstructed in the same area.
Vice President Brian Sousa of Wade Trim, project manager for the sewer repair work, says East Bay officials tried to coordinate both projects to take place at the same time. “The township requested to repair the sewer force main concurrently with the road repair project through a trench-cut approach,” says Sousa. “MDOT (Michigan Department of Transportation) did not allow the joint work after review of the request. Unfortunately, at the time of the road repair, there were breaks in the line during that construction, with the cause unknown. Many attribute the breaks to the brittleness and age of the line coupled with the vibration of the road repair. At any rate, in fixing those breaks, it secured the fact that this line needed to be addressed.”
Aging sewer lines also pose challenges in Traverse City, which experienced two sewage spills into the Boardman River within two weeks at the same location following flooding events. In the first incident on May 28, an estimated 54,000 gallons of raw sewage spilled into the river after one of three pumps at the city’s lift station on East Front Street (pictured) failed to activate due to a software glitch. Three-plus inches of rain poured on parts of the city and downtown, overwhelming the pump station and causing sewage to back up from a manhole at Union and Front.
On June 10, a much smaller spill – approximately 2,500 gallons – occurred at the same site during another rain event that dumped nearly 2.5 inches of water. This time, all three pumps at the lift station worked as intended – but the surge still overwhelmed the system, with sewage oozing from the same manhole at Union and Front. In both cases, the Grand Traverse County Health Department issued no-contact advisories with downtown waterways and beaches until testing levels indicated E.coli levels were safe enough to lift the warnings.
A number of factors have been contributing to reducing the sewer line’s capacity and overwhelming the system during hard rain events, according to Traverse City Director of Municipal Utilities Art Krueger. Several sections of city pipeline are made out of clay, with some still in use that were built as early as the 1930s. Unlike with a jointless pipe created by a CIPP, the joints found in clay pipes are “not 100 percent sealed” and allow in excess groundwater. High river and lake levels and ground saturation means water “has nowhere to go” during flooding events, Krueger says, increasing the likelihood it will stream into pipes. Homeowners in low elevation areas – such as the west side of Traverse City – who have crawl spaces or basements are also likely battling frequent flooding and may be pumping that water into city sewers, not realizing that doing so is illegal.
“We have a concern that a lot of people have illegally tied into the city sewer…and that’s directly taking away some capacity for the sewer mains to handle what they can,” says Krueger. He says residents should ideally be relocating water away from their home to a different ground location, such as a in ditch or French drain. The city’s municipal department is willing to advise any residents or conduct house visits to help them find legal solutions for discharging water from their sump pumps to avoid overwhelming the city's system (the department can be reached at 231-922-4900).
Traverse City commissioners Monday approved spending just over $132,000 out of the city's sewer fund for new auxillary pumping equipment and suction and discharge piping to help regulate flow at the Front Street lift station. The city is also analyzing other solutions to address the overflow issue on Front, according to Krueger, who says he understands public concerns about two sewage spills occurring at the same site in two weeks. However, he cautions that overflow will remain a risk as long as the city has limited resources and miles of aging pipeline to address. A 2017 study found that Traverse City would need to spend $2 million annually in perpetuity for city stormwater system maintenance – and up to another $1 million annually in wastewater repairs – to adequately fund its system. Paying for repairs of that magnitude isn’t feasible for most municipalities through regular budget mechanisms or even increased sewer rates; most turn to millages or special assessments, such as through a stormwater utility, to cover the costs. But with Michigan law murky on whether local governments in the state have the authority to create stormwater utilities – and with residents often resistant to tax or rate hikes – municipalities like Traverse City, East Bay, and Acme must often tackle their aging infrastructure one half-mile stretch at a time.
“It takes a long time to get infrastructure projects designed and bid out and constructed, and they can each cost hundreds of thousands of dollars,” says Krueger. “Budget-wise, we only have so much to work with each year. We’re trying to spend those dollars as wisely as possible.”Comment