City Struggles to Manage Sewage Overflows in Short Term

Aug 3, 2016

Sewage Overflow at Crane Creek on December 31, 2015
Credit Bill Stangler

Since October's historic flood last year, there have been twenty sewage spills, overflows, or line breaks that released over 10,000 gallons of raw or under-treated sewage in Columbia. Those numbers were reported by the state's Department of Health and Environmental Control.  Columbia has dealt with sewage overflows for decades, as many other cities with outdated collection systems have, but October's historic flood shined a light on the continuous problem.  Cooper McKim speaks with experts from various fields about the ongoing problem.

Down a narrow road in Columbia, under several criss-crossing highways, a stream is barely flowing.  Speeding cars can be heard overhead whirring by. Sarah Rothenberg comes here frequently to take water quality samples with students.  "Every time we get out here, you'd get out of your car and you just knew you were at the sewage site," says Rothenberg, an Assistant Professor of Environmental Health Sciences at the University of South Carolina.  She's at Crane Creek with a graduate student, Maggie Emmons, where they're testing bacterial levels in the water.

Yellow Star: Site of Dec. 31st spill that exceeded a million gallons Black Line: Part of Crane Creek feeding into the Broad River Red Symbol: Columbia's Water Treatment Plant.

Crane Creek is a hot-spot of what's called Sanitary Sewer Overflows (SSOs) -- when sewage pipes running through the area reach capacity or break, releasing sewage. Here, the pipes are particularly old. Even an inch of rain can cause them to overflow, pushing rainwater and sewage out of manholes onto the road above.

Emmons describes one occurrence of an overflow right by the quiet stream. She says, "when the sewage was overflowing, this was all covered with raw sewage... the water used to be up to about where the road was."

Crane Creek feeds into the Broad River, where Columbia residents get their drinking water.  On December 30th, DHEC reported that over a million gallons overflowed here due to excessive rain. Rothenberg wonders whether that's safe. She says, "so raw sewage contains viruses.  If you drink the water you're going to get sick. And if you have body contact with the water, you could get sick."

Manhole overflowing at Crane Creek site
Credit Bill Stangler

What happened December 30th is not unique. There have been 150 SSOs since October 3rd.  Many of them minor, but several have exceeded a million gallons by some estimates.  Bill Stangler is the Congaree Riverkeeper and a monitor of SSOs in the region.

Columbia has approximately 1200 miles of sewer line. Much of it dates over 100 years, with minimal investment in maintenance in that time.  Stangler explains, "it all goes back to what I've seen called 'the lost decade' of infrastructure spending. Sewer pipes are underground, they're not a sexy project, nobody goes to city council meetings and say 'You've got to fix these broken sewer pipes' when you can build something fun."

He adds that Columbia has been seeing the consequence of that decision for years now, but without awareness of the city, DHEC, or the EPA.

Congaree Riverkeeper on Twitter

In 2012, the EPA negotiated an agreement with the city of Columbia to reduce their sanitary sewer overflows. At the time, there were twenty-two SSOs per hundred mile. Richard Elliott, an enforcement officer with the U.S. EPA, explains, "while it should be noted that SSOs occur in every single sewer system in the whole wide world... 22 per hundred mile is a significant number which got the attention of EPA."

Columbia was given until 2025 to make serious improvements to the system. Nevertheless, three years since the agreement has been active, SSOs have continued frequently. Leaks have made their way both into the Broad River, where Columbia gets its drinking water, and the Saluda River, where residents recreate.

HEALTH EFFECTS

Release of sewage into a body of water can cause health issues.  EPA's Richard Elliott explains sewage carries pathogens, bacteria, and nutrients that, when ingested, can "deplete the oxygen that's available for fish and cause fish-kill," says Elliott. 

"It wasn't broken yet, so it seems like'Okay if its not broken now, put it off a couple years' and that's kind of how things got to where we are now."

It can affect humans as well.  Rothenberg says, "raw sewage contains viruses, so if you drink the water you're going to get sick. And if you have body contact with the water, you could get sick." She says exposure can cause gastrointestinal problems or infections in your ears and eyes. 

City's Actions

"Any time we have an SSO, it's not a good thing," says Joey Jaco, head of Columbia's Utilities and Engineering Department. Jaco says the city is concerned and is doing everything they can to minimize them. 

In the short-term, that means finding the SSOs and stopping them as quickly as possible. "We're walking lines, videotaping, doing this SL-RAT [Sewer Line Rapid Assessment Tool], smoke testing, dye testing, we're doing all kinds of things daily to investigate our system," says Jaco.

"While it should be noted that SSOs occur in every single sewer system in the whole wide world... 22 per hundred mile is a significant number which got the attention of EPA."

Still, he says the department is doing much more preventative work than reactive work at this point.  When it comes to real progress, he says it's not about the short-term. His department is focusing on investigative work where big investment projects will clear up large swaths of troubled areas. Crane Creek, for example, is a consistent hot-spot for SSOs. The city has already invested over a hundred million in capital projects there -- fixing these spots, he says, will drastically reduce annual overflows.

Jaco explains, "we're replacing sewer line, we're rehabbing sewer line, we're building manholes, we're building storage within the system, and we're up-sizing pumping within the system."

With 1200 miles though, Stangler, Rothenberg, Elliott, nor Jaco expect the problem to disappear soon.  Jaco says, "grtting to the point that we have eliminated them as much as we possibly can is years away... we're doing a lot of things right now. But it's not gonna happen in a couple years. We're talking probably 10-15 years to really see the effect."

Richard Elliott agrees. With decades of neglect from Columbia's city council, there will continue to be SSOs for years to come. Elliott posits, "we expect there to be more than ten years amount of work to get a comprehensive fix that EPA would consider to a level that we would consider there to be terminating a [consent decree]. There's a significant amount of time to build those projects, to design and build, a lot of the time has to actually is taken up finding out what you have and what you need."

Rothenberg responds that 2025 is a long ways away, "and in the meantime, we have to live with these SSO's"

DHEC ACCOUNT OF SANITARY SEWER OVERFLOW IN COLUMBIA