What lies beneath
As people have moved away from densely populated urban areas with centralized sewer systems, the number of onsite, cluster and community wastewater treatment systems — known collectively as decentralized systems — has steadily increased. Once viewed as short-term solutions until centralized systems could be constructed, onsite septic and cluster systems serve nearly 25 percent of all U.S. households and up to 33 percent of new development, according to the Washington-based U.S. Environmental Protection Agency (EPA).
Unfortunately, like some urban sewer systems, many of the small systems are aging and need repairs. But, because decentralized systems usually discharge to groundwater, they largely are not federally regulated under the Clean Water Act and generally go unmonitored. Usually, state, county or local health departments are responsible for their oversight, and the homeowners are in charge of maintenance — jobs that the health departments and homeowners often fail to do, threatening public health, water resources and the environment.
Buried and forgotten
EPA estimates that more than half of the decentralized systems in the United States are more than 30 years old, and at least 10 percent might not be functioning properly. Agency officials believe that, in far too many cases, the systems are installed and largely forgotten until problems arise, including contamination of drinking water supplies, groundwater and surrounding water bodies.
“Historically, we had low enough population densities that a malfunctioning septic system was not a big deal,” says Stacy Passaro, manager of technical and educational programs for the Alexandria, Va.-based Water Environment Federation (WEF). “Even if they failed, it wasn’t going to have a negative impact on public health and water quality because the natural environment could assimilate the pollutants. But over time, as we pack more and more people onto smaller lots, it becomes more and more of an issue. High population densities stress the environment and our water resources in many ways. In order to protect and maintain these resources, we have to do everything better — maintain and upgrade our centralized wastewater treatment systems, manage our stormwater and properly manage our decentralized wastewater systems.”
Often, if developers cannot get approval to tie new developments into an existing centralized system, they apply for and receive permits for subsurface discharge systems. The systems could be sized to serve individual homes or small clusters of 10 to 50 homes. Alternately, “package plants” could be commissioned from vendors that service between 50 and 1,000 homes each.
Oversight and management is left to the appropriate health department, which often lacks staffing resources and monitoring requirements. That sometimes results in the installation of inappropriate treatment technology. For instance, onsite septic systems installed on a flat landscape with a good drainage field might not have any problems, but the same system installed in clay soil will fail almost immediately because of lack of absorption. “Without the resources to do regular inspection and monitoring, there’s really no way to catch it if something goes wrong,” Passaro says.
EPA is encouraging states to update codes to address new technologies and problems. “It’s just a matter of fixing the regulatory structure that we have now and improving the outdated regulations,” says Joyce Hudson, manager for EPA’s Decentralized Wastewater Treatment Systems Program. “A lot of state and local regulations have not kept up with development and advancements in technology, so it doesn’t allow the proper types of systems to be put into place.”
One community takes action
Some communities, like Loudoun County, Va., began addressing the problem several years ago. Historically a farming community located 25 miles outside of Washington, D.C., the eastern portion of the county is considered a suburb of the nation’s capital, while the western portion remains rural farmland. Recognizing the potential for growth and prompted by the desire to preserve the county’s rural heritage, officials mandated a dividing line between the eastern and western portions of the county in the early 1990s.
Wastewater services for the suburban eastern portion are centralized, and the western portion has decentralized systems. The state regulates both through the sewage collection and treatment (SCAT) regulations that govern most municipal and large flow systems, and the sewage handling and disposal regulations that govern decentralized systems.
The towns are served by municipal wastewater treatment, and the Loudoun County Sanitation Authority (LCSA), which is separate from the county government, manages wastewater service provision in the unincorporated sections of the county. LCSA practices a form of distributed wastewater management, operating a large central system in the suburban east and the decentralized community systems in the rural west. The decentralized community systems primarily are surface discharge systems requiring a National Pollution Discharge Elimination System permit, but they also include subsurface discharge systems permitted through the local health department. Typically, developers purchase package plants that service between 50 and 350 homes each and then, according to LCSA’s standards, deed the systems to the agency for management.
LCSA helps plan, design, construct and operate community systems. It works with developers to identify appropriate technologies for the size system the developer wishes to design and construct. It has design standards that supplement the state SCAT regulations and help assure that the systems are of high quality and reliable. LCSA also works closely with its regulators, including the local health department that oversees the subsurface discharging systems. In fact, LCSA is assisting the local health department in updating the county’s individual onsite systems ordinance to more appropriately regulate advanced onsite treatment systems and require management and maintenance by licensed companies.
Like residents with centralized systems, homeowners pay a quarterly water and sewer bill to LCSA. “Right now, we have unique rates for each community because our policy is that each of these systems must be self-sustaining,” says Todd Danielson, LCSA’s manager of community systems. “Loudoun County decided to let communities develop only if they could support it based upon their own individual merits for water and sewer. Essentially, it makes each subdivision pay for itself, and there are no county resources expended on the systems.” Because of the self-sustaining policy and the quality and reliability standards, LCSA currently only consents to own and operate systems serving 15 or more connections.
‘Management is key’
While Loudoun County has a handle on its decentralized systems, other communities still struggle with the issue. “Right now, it’s very sporadic in terms of what the requirements are,” Hudson says. “For centralized wastewater plants, the operator must be certified at a certain level and go through regular training, but for onsite systems, in many places, you don’t need any type of certification to install one.”
Passaro says that city and county officials should consider the watershed as a whole before developing plans to suit specific areas. “We’re never going to be able to afford to sewer the whole country, so these smaller systems are here to stay,” she says. “Right now, it’s just not set up to encourage people to do the right thing the right way. We need to work together to promote sound technology, sound principles and sustainable management of this infrastructure.”
EPA is educating local officials and homeowners about the importance of properly managing their decentralized systems. “Management is key to this issue,” Hudson says. “So we’re recommending that there be a management entity — some type of group that regulates and manages an area of systems.”
Pennsylvania’s code for decentralized treatment systems is managed through local governments as instructed by the state Department of Environmental Protection (PA DEP). “It’s impossible to have a workable state program if you don’t distribute responsibilities to local entities,” says Ed Corriveau, chief of wastewater planning and finance in south-central Pennsylvania for the PA DEP. “We can’t be out in everybody’s backyard, so we recognize that municipalities have to do it.” But getting municipalities to do the right thing, he concedes, is not easy. “We have some that do and some that don’t.”
To assist communities in setting up a management plan, EPA released a handbook for managing onsite and clustered wastewater treatment systems in December 2005. In addition, the agency has developed a free inventory database for homeowners; training for health departments, pumpers, designers, installers and decision-makers; and is providing funding/encouragement to help organizations, such as WEF and others, develop training and certification programs.
In 2005, EPA also signed a memorandum of understanding with several organizations to provide direction and support to improve the performance of decentralized systems by promoting continuous management and facilitating upgraded professional standards. The Small Communities Committee and other technical committees for WEF are developing new workshops, Webcasts and special publications to help decision-makers assess treatment options and develop criteria to help make the best decision for their communities. “Basically, there is no one-size-fits-all solution to developing sustainable wastewater management solutions,” Passaro says. “As a sector, we need to get better at assessing each specific application and matching the appropriate technology with the long-term performance requirements. We need to use our limited infrastructure funding wisely and build in flexibility for the future.”
EPA plans to work with realtors to encourage homeowners to improve their onsite septic systems and states to require inspections before homes are sold. “For some states, it is already a requirement,” Hudson says. “But we would like to see more adopt a mandate so that the owners will fix their systems prior to selling to an unsuspecting buyer.”
Although it will take time to put better management practices into place, Corriveau believes that oversight of the systems is unavoidable. “If people can’t tie into existing pipe, they are going to build onsite [wastewater treatment systems], it’s that simple,” he says. “With a continual need for growth beyond pipe, everyone’s recognizing that distributed wastewater management systems is the way this country is going.”
Lori Burkhammer is director of public information for the Alexandria, Va.-based Water Environment Federation.