Washington Suburban Sanitary Commission Tackles Its Infrastructure
September 21, 2011The Washington Suburban Sanitary Commission (WSSC) is the eighth largest utility in the United States, serving nearly 1.8 million residents in the greater Washington, D.C., area, and maintaining a combined 10,000-plus miles of water and sewer lines.
But with its billion-dollar capital and operating budgets, it still faces the same challenges that smaller utilities and cities do: an aging infrastructure and limited funding to handle it.
Today, the WSSC is in the midst of a multi-billion, court-ordered, 12-year program to evaluate and upgrade its aging maze of sewer lines to address excessive sanitary sewer overflows (SSOs). And trenchless technology is playing a critical role in this plan, specifically cured-in-place pipe (CIPP).
Yes, other U.S. utilities and cities are undergoing similar court-mandated programs; however, WSSC is faced with doing it on a much larger scale and media stage than most — given its size and proximity to the nation’s capital.
WSSC serves approximately 460,000 customer accounts and provides water and sewer services to two Maryland counties adjacent to the U.S. capital, Prince George’s and Montgomery, covering 1,000 sq miles.
Today, WSSC is one of the country’s largest utilities, with a $1.192 billion capital and operating budget for 2012. That’s a far cry from when it came into existence in 1918 when it spanned just 95 sq miles and serviced 30,000 people.
Its infrastructure challenges have made headlines across the Internet and TV, given its proximity to Baltimore and Washington, D.C. — the hub of the political world, as well as a popular tourist spot and where water main breaks and sanitary sewer overflows get more media coverage than smaller utilities in less eye-catching cities.
WSSC has grown into a utility that employs more than 1,500 workers. Its budget is large and complicated and must address the needs of a huge customer base all the while being cognizant of spending and charging its consumers.
WSSC, established in May 1918, was the brainchild of the public health officials and civic leaders. After its birth, WSSC growth started immediately as more communities were integrated into the system and filtration plants and reservoirs were designed and constructed to meet its expanding customer base.
As an indication of the growth of the commission’s water service reach, since 1920, when average water production was little more than 300,000 gal per day, the WSSC established a distribution record of 267 million gals (mgd) on July 8, 1988. Today, the annual average, daily production in suburban Maryland is 167 mgd and the commission’s water distribution network stands at 5,500 miles.
On the wastewater side, the first sewer constructed by WSSC was installed in 1919 in Riverdale, Prince George’s County and expanded to include several communities in Maryland throughout the 1930s and 1940s. Today, all major trunk sewers in Montgomery County, with the exception of the Great Seneca Sewer Basin, are connected to the regional Blue Plains System, built after World War II and has a present day capacity of 370 mgd, of which just over 179 mgd has, by agreement, been allocated the WSSC. Throughout the 1950s and 1960s, WSSC began to develop its own permanent sewage treatment facilities, located in
Prince George’s County. Today, WSSC operates more than 5,400 miles of sewer.
“Our water and sewer pipes are old. The system’s infrastructure is aging faster than we can replace it,” WSSC chief engineer Gary Gumm states matter-of-factly. “Our utility is 93 years old and some of the pipes are older than us because we assumed control of infrastructure that was already in existence.”
According to WSSC, more than 2,500 miles of its mains are more than 90 years old, 1,400-plus miles are more than 50 years old and 1,600-plus miles are less than 25 years old. The pipes are made up of steel, ductile iron, cast-iron, pre-stressed concrete cylinder pipe, concrete and clay.
As with any aging infrastructure, costs to maintain and/or upgrade also continue to rise, making it critical that WSSC make smart, cost-effective decisions on how it spends its capital budgets. Unfortunately, it falls to the ratepayers to cover the costs of the work that needs to be done — from routine maintenance issues to the costly rehabilitation work under way.
“Our infrastructure needs have continued to rise as our infrastructure ages,” Gumm assesses. “[Our needs are] continuing to rise more than we are able to fund and that’s what makes our life a little difficult. We have to balance the funding we get — even though it’s going up and not commensurate with the need. Other utilities are experiencing the same thing.”
A way that WSSC has worked to keep escalating costs from mounting any higher than need be and keeping projects from disrupting its communities is employing trenchless technologies. On the water side, WSSC has used jack and boring to restore house service connections, as well as trenchless robotics and inspection technologies and electromagnetic wave testing as part of its inspection program. On the sewer side, CIPP is used for pipe and lateral relining, as well as pipe bursting and some microtunneling and horizontal directional drilling.
“In the right circumstances, [trenchless] is a lot cheaper and open-cut is very expensive,” Gumm says. “There is much more impact on the community when you are digging up their streets vs. using CIPP and going through the manholes.
A 2005 legal settlement between WSSC and the U.S. EPA, the Maryland Department of the Environment and four environmental groups that had sued the utility, claiming it violated the Clean Water Act by having too many SSOs, resulted in a 12-year plan to evaluate, rehabilitate and upgrade its system. The aim of the consent decree was to eliminate or drastically reduce the SSOs that result in water backups in basements and inflow and infiltration of sewers and manholes. An agressive fats, oils and grease (FOG) program has also been established.
Halfway through the program, WSSC says it’s too early to tell how effective the work has been but the signs are pointing to a better and stronger system for its customers, noting that SSOs are coming down. WSSC says that it’s “put out some hot spots” but not enough work has been done to quantify anything right now.
“We don’t have nearly the problems here that other utilities do but we have the consent decree and its purpose is to eliminate or drastically reduce our SSOs,” Gumm says. “Are we different from any other utility? No, I think we are bigger and older than some but the dynamics are the same,” he says. “The Rust Belt down to us — we are older, larger communities with infrastructure that’s been around awhile and nobody has found the fountain of youth for infrastructure. You have to stay with it and stay on top of it. You can’t just forget about it. And things underground tend to be forgotten about until they break down.”
The parameters of the consent degree are threefold: evaluate, design and correct. That’s it in a nutshell and while the 154-page document can be summarized in those three words, the reality and scope of it cannot.
The first phase of the order has WSSC inspecting and investigating its entire sewer system and then assessing the condition of the lines, followed by determining the best course of action to correct any problems. To date, more than 3,000 miles of sewer lines have been inspected for cracks, defects, roots and grease.
“We walked the major trunk lines and in some cases, got into them with inspection cameras and then figured out what we needed to do and then made a plan to turn in to regulators,” Gumm says.
As the inspection process proceeds, WSSC has begun some of the construction and rehab work on lines that have been evaluated. All costs related to the consent decree are estimated to cost at least $500 million over the 12 years. All consent decree mandates must be met by 2015.
“And [the cost] is not as bad as some that are out there, believe it or not,” Gumm says. “But we are starting to get to the point where we are spending money that’s becoming noticeable. We’re getting into construction phases now where it costs more than the investigative work.”
And unfortunately for ratepayers, they are bearing the brunt of these costs. “Nobody gives you money for this. It all comes from ratepayers and is leveraged over time with bonds,” Gumm explains.
Nobody appreciates the sacrifices that WSSC’s customers are making more than WSSC, especially during such hard economic times. “We’re asking for more money from them and they are living in this economy,” Gumm says. “People are losing jobs and having a harder time paying for stuff and we are asking for money in some cases. That is very tough and very difficult.”
The work being done under the consent decree includes manhole repairs, pipe relining using CIPP on a large scale, as well as lateral lining. “We are experimenting with different trenchless methods,” Gumm says, especially in its lateral program, which is a new area WSSC is venturing into using trenchless. “If you are really going to tackle a problem with sewers that leak, you have to tackle the laterals. A large percentage of the problem is the lateral itself or where it ties into the homeowner at the property line or into the main. All of those are weak points where you may be getting a lot of infiltration. Some laterals are too far gone for trenchless methods. We don’t have cleanouts in most of ours so you have to start by installing those.”
And that’s just on the sewer side. On the water side, which is not covered by the consent decree, WSSC has an ambitious plan to upgrade its system. “We are putting a lot of effort in water,” Gumm says. “We are ramping up our water line replacement to five miles a year. We are at 41 miles in 2011 and heading 55 miles in 2012.”
While replacing its water lines is a project for today, Gumm says in the future, its larger water mains — upward to 96 in. in diameter — will need to be addressed. “Our biggest problem down the road is our large water mains and when we replace them and how we will do it. We are counting on the trenchless industry to come up with a structural solution for large water mains. It’s hard to take pipes of that size out of service for very long,” he says.
While the EPA-mandated work is only halfway completed, WSSC has learned a few things about itself along the way — lessons that will serve the utility well into the future. As the saying goes: An ounce of prevention is worth a pound of cure.
“I think we learned what we probably already knew and that is we got a little behind on some of our maintenance tasks. In the past, we had an initiative to get our costs down. We had eight years with no rate increases and we lost a third of our workforce, and along with it went a good chunk of maintenance activities they would do,” Gumm says. “What we learned was: You don’t get rid of your maintenance stuff. That is not where you save money.
“Being reactive gets expensive and it’s a compounding problem,” he adds. “As you continue to react you are not taking care of your proactive measures. It’s a dangerous dynamic to be in. That’s why we’ve increased our water main reconstruction program to try to stop that bleeding.”
When looking into the future, what does Gumm see as the key issue facing utilities? Pretty much what he sees happening to them today, just on a more costly scale. “It’s the same exact thing we as individuals face: We are getting older,” he says. “The infrastructure is getting older. We’re going to have to spend more money taking care of it. We need to spend money doing those proactive things: more inspections, more leak detections, more valve work, more condition assessments — more of everything.”
And don’t forget more money. “We are not going to get the money we need,” Gumm says. “We are going to have to do very smart things with the funds we do get.”
Sharon M. Bueno is managing editor of Trenchless Technology.