When it rains, Nashvillians tend to their basic indoor activities without hesitation. They drink water from faucets, take showers and flush toilets, giving little thought to the sea of infrastructure that allows them to do so.
But underneath the labyrinth of streets and homes that make up the neighborhoods dotting Davidson County, a struggle plays out inside the city’s pipes during these seemingly harmless moments of rainfall. Nashville’s two sets of sewers, one by structure and one through deterioration, aren’t equipped to prevent overflows induced by heavy precipitation that enters the system. As a result, fecal matter that exits a homeowner’s toilet can make it into the county’s waterways.
The price tag for fixing the problem is huge. Over the next decade and beyond, Metro must spend as much as $1.5 billion to comply with an Environmental Protection Agency-mandated upgrade to its sewer system just to become compliant with state and federal guidelines.
It’s construction work so fundamental, so mundane to the fabric of any city that not many people are aware the process has already begun. But while sexier issues involving Nashville’s new convention center, potential property tax hikes and discussions about a new minor league stadium garner the bulk of headlines, Metro officials are taking Nashville’s water infrastructure overhaul just as seriously.
“It’s clearly one of the most significant individual items that the city will ever do,” Metro Finance Director Rich Riebeling told The City Paper.
“People aren’t going to see it,” he said. “It’s not like a convention center where you see a building on a street. It’s all underground. It’s infrastructure improvements. And it’s all environmentally driven. It’s something where we’re sort of paying the price for the way things were done decades upon decades ago.”
Dissecting the monumental task requires an overview and history of Nashville’s two separate sewer systems.
Below the oldest geographic section of Nashville –– collectively known as the urban services district, which includes areas like downtown, East Nashville and West End –– are aging pipes that date back to the 1880s, a period when the city, like others, simply covered and converted creeks into sewers to divert waste and stormwater to the Cumberland River. Over time, the network evolved into Metro’s existing combined sewer system, disposing into the river — through the same set of pipes — both stormwater runoff as well as sanitary sewage collected at homes and businesses. Combined sewer systems are no longer built, but they still operate in the middle of Davidson County.
By the mid-20th century, the city began building treatment plants to filter the combined sewer water. Nonetheless, when rainfall becomes excessive, these plants are unable to hold the surge of water. The result is overflows at the same locations where pipes years ago dumped untreated water directly into the Cumberland and its tributaries. Unlike a century ago, the discharge is unintentional.
“We’ve got sites that overflow as many as 50 times a year,” said Ron Taylor, project manager of Metro Water Services’ Clean Water Program. “The key there is we have to reduce that frequency of overflow to an acceptable level.”
Twenty-five years ago, Nashville had 32 of these combined-sewer-overflow discharge points. After millions in expenditures in the 1990s, the list whittled down to eight on various points of the Cumberland. Workers eliminated one of these overflow sites –– downtown, where Lower Broadway intersects with the river –– two weeks ago by blocking its entry point into the river.
“When combined overflows occur, it’s a lot of rainwater and a little bit of sewage,” Taylor said. “But still, you can have elevated levels of bacteria in the river following a rain event for a period of time.”
In more recently built, suburban parts of the Davidson County, the sewer layout is different, but problems still persist. There — in the county’s periphery from Antioch to Madison to Bellevue — Metro installed separate stormwater and sanitary sewage pipes. The issue here is 1950s-era clay and other non-plastic pipes that have deteriorated and cracked over years of moisture. When precipitation hits the ground and infiltrates the soil, groundwater often leaks into these sanitary sewage pipes. Extreme amounts of stormwater into sanitary pipes create overflows at low areas like manholes.
“When you get a big rainfall event, that sanitary sewer capacity is exceeded,” Taylor said. “And then you can get overflows in the low points. . . . That can be in areas that can affect public health.”
The condition of Metro’s water infrastructure –– stressed during large rain events –– has put Metro in line for a financial undertaking that will likely be its largest over the next decade. City officials have no real choice in the matter.
Four years ago, federal and state officials approached Metro about the need for additional sewer investments. Shortly after, the EPA and the Tennessee Department of Environment and Conservation filed a consent decree in federal court requiring Metro to comply with a list of environmental regulations. By March 2009, the consent decree was approved, setting aside a schedule whereby Metro must submit a long-term plan to address the issue. Nashville’s historic May 2010 flood delayed the timeline.
On Sept. 9 –– the deadline was two days later –– Metro turned in what’s known as its Long-Term Control Plan, a 906-page document, bound together in a 4-inch binder, which, item-by-item, details how the city plans to address combined sewer overflows through various construction improvements. As stipulated by the consent decree’s schedule, the improvements must be implemented within 11 years.
The plan’s creation came after a 16-member citizens’ advisory committee spent nearly two years meeting with Metro officials to review the impact on affected neighborhoods. There were also 10 community meetings. Metro hired global engineering consulting firm Camp, Dresser and McKee, which subcontracted AECOM to help develop the plan. Nashville-based public relations firm Hall Strategies and architects Gresham, Smith and Partners also worked on the project.
In a recent interview with The City Paper, Taylor –– whom Metro promoted in July to push the program forward –– held the long-term plan in one hand and another binder in his other. In this equally large document is the city’s “corrective action plan/engineering report,” which deals with repairing suburban-area separate sanitary lines.
Both documents are under review by the EPA and TDEC, a process expected to conclude within six months. Either way, Metro officials project the overall cost to range from $1 billion to as much as $1.5 billion over 11 years. The final dollar figure isn’t settled because the EPA could elect to make additional changes to the plan. In addition, costs could escalate over the 11-year period.
Paul Davis, director of TDEC’s Division of Water Pollution Control, called the recently submitted long-term plan an “ambitious undertaking.” He also suggested it would likely gain approval from the various state engineers reviewing it.
“I know this is good work,” Davis said. “It’s well considered. It brings in the budget within the timeframe. So it’s unlikely that an engineer at the state government is going to take a casual look at this and say, ‘Come to think of it, you should use this size pipe instead of that size, or you should prioritize this in front of that.’ ”
Nashville is not the only municipality that finds itself with a sewer question. The EPA has ordered cities across the country to address environmental sewage issues via consent decrees, including the city governments of San Diego, Indianapolis, Louisville, Ky., and Pittsburgh.
Still, the potential $1.5 billion price tag of Metro’s massive overhaul shouldn’t be ignored. Consider that Metro’s budget for the current fiscal year –– which accounts for the salaries of most Metro employees and the operations of city departments –– is $1.59 billion. Similarly, the expected cost of Nashville’s 1.2-million-square-foot Music City Center is $585 million, plus a $300 million headquarters hotel.
Riebeling, who in 2009 helped engineer a water rate hike and Metro’s first-ever stormwater fee to bankroll stormwater infrastructure upgrades, said funding for the city’s sewer endeavor would come partly from user fees. Metro Water is a revenue-funded department, sustained by its rates and receiving no general Metro funds. He said the city is in the process of conducting a rate analysis to see how the city’s current rate structure measures up with required future spending.
Initial funding for the $1 billion-plus bill would be generated from the department’s revenue bonds, he said. Metro would likely begin issuing bonds –– likely totaling “a couple of hundred million dollars” –– in 2013. Nashvillians’ water and sewer fees pay off these bonds.
“Because of the way we’ve structured the debt, because of the rate increases we’ve done, we think we’re going to have some significant ability to fund projects,” he said.
Riebeling, who said Metro Water is in the best financial shape it’s been in a decade, pointed out the department is currently paying off nearly $70 million annually in debt service through its fee collections. But in a few years, that figure drops dramatically to approximately $30 million in yearly debt payments.
“If the rates are already paying at $70 million, and they drop off, then that’s $30 to $40 million in capacity on an annual basis, which would fund [between $300 million to $400 million] worth of bonds without any change in the rates.”
The city’s ongoing three-year water and sewer hike, which began with a 7.8 percent jump in 2009, came after an outside consulting firm in 2006 recommended new rates that would produce twice the amount of revenue that the city is currently collecting.
Metro Councilwoman Emily Evans, who supported an alternative stormwater fee structure in 2009, said though rates could have been raised further, the city simply didn’t have the documents to know what it needed to fund.
“Without having the CAP-er (corrective action plan) done, and without having done all the technical work around the consent decree, we probably raised them to handle the immediate capital needs, but not the long-term capital needs,” Evans said.
“I think the thinking at the time was that the economy couldn’t handle the additional costs,” she said. “So, the upside of that is you’re not raising rates. The downside of that is you’re not necessarily going to get all the capital projects that you need done.”
Construction projects to adhere to the EPA consent decree aren’t likely to turn many heads. Most won’t realize they are part of a long-term plan to address billions of dollars in upgrades. In fact, Metro has already started on some improvements that officials know are necessary even before the EPA signs off on the city’s plan.
In addressing Metro’s combined sewer system, conventional wisdom suggests replacing it altogether with separate sewer lines. But doing so would tear up streets and neighborhoods, and cost billions more than the city could expend.
“So, what you really try to do is reduce the overflows so that you mitigate any water quality problems that you create,” the water department’s Taylor said.
Talking in broad terms, Taylor described a “three-pronged approach” to fix both the combined and separate sanitary systems. That includes inserting lining in leaking non-plastic pipes in suburban areas, a process that is achieved without tearing up streets, he said.
He also said Metro would be increasing the conveyance capacity of the sewer system through the addition of larger pipes. Thirdly, he said storage tanks would be built to temporarily hold water during rain events. When the rain subsides, the water would be released back to treatment plants and then into the natural water system.
“There’s quite a bit of construction in various areas,” Taylor said. “The good thing is a lot of this construction, like storage tanks, are typically not in neighborhoods. They’re in areas that are toward the river, more commercial- and industrial-type areas.”
The EPA’s order required Metro to form a citizen-led committee representing every neighborhood that relies on the city’s combined sewer system. The group toured various water department facilities. Officials also provided members a comprehensive look at the forthcoming billion-dollar task.
“The way I look at it is, there is a pretty sophisticated formula that dictates whether or not Nashville will ultimately be in compliance,” said Freddie O’Connell, a committee member representing the Salemtown/Germantown area. “That includes all the projects that are on the table. Basically, our role was to be kind of a weight on one of those variables.
“It wasn’t the kind of thing where we as volunteers were giving yes or no, up or down,” he said.
Kenny Byrd, who resides in East Nashville’s Edgefield community and served on the committee, said Metro officials spent an enormous amount of time educating them on “the problem and the potential solutions.”
“We were not responsible for giving the final solutions; we were giving input,” Byrd said, adding that the group wasn’t asked to budget or devise ways to pay for improvements.
Though one goal is to minimize the effect on neighborhoods as much as possible, there could be situations in which some public spaces experience some changes. For example, under the submitted plan, a storage tank could be built in East Nashville’s Shelby Park to quell an overflow in that area.
“That initially concerned me greatly,” Byrd said. “I had a major concern about that, and voiced it. However, given what we learned over the course of our work, it may very well be the most efficient and effective plan.”
It would likely be three to four years before that portion of the plan nears implementation. Byrd said he expects ample community input to take place prior to its construction, including reaching out to the group Friends of Shelby Park. Metro officials understand this concern, he said.
“If we are going to do a [storage tank] in a park, I want the community to be very involved in how that happens,” he said.