Sewer showdown: Septics vs. the 'big pipe'
When it comes to selecting the superior wastewater treatment system, septic or sewer, science says it's a wash.
As the Minnesota Pollution Control Agency Citizens' Board met Tuesday to decide the fate of the disputed Central Lakes Region Sanitary District wastewater treatment facility, one of the deepest disagreements over the project has been whether or not it will improve water quality in Douglas County.
Supporters of the proposed $53 million plant say centralized sewer is the way to go. Those opposed argue septic systems are just as good, if not better.
In an attempt to settle the debate, the Echo Press sought advice on the issue from several experts in the field.
Here's what they had to say.
Dave Rush, director of Douglas County's land and resource management department: "The county has no jurisdiction, no point of view [over CLRSD]. We are not supporting one direction or another."
It's up to residents, he said, to decide how they want their wastewater cleaned.
Rush said there are advantages and disadvantages to both septic systems and centralized sewer, and the county's priority is getting as much information out to the public as possible.
One of the drawbacks to septic tanks is that they are hard to police, he said.
"There was a number that somebody said 93 percent of [septic] systems [in Douglas County] are compliant," Rush said. "Not true.
"We believe that of the estimated 1,100 parcels in the Miltona/Irene area with wastewater generating structures, an educated guess is that almost 900 could have been installed pre-1980," he said.
Of this number, "There are 700 parcels around lakes Miltona and Irene for which the county has no septic system data on file [at the Land and Resource office]," Rush said.
"One reason for this may be that parcels were built on and septic systems installed prior to 1966 when the county began keeping records," Rush said. "It is highly unlikely that a septic system installed before 1966 would be compliant with today's standards."
The county doesn't actively enforce compliance, he said, only checking in when new systems are installed or other property modifications require a permit.
"With a centralized system, we're not responsible for ensuring compliance; the [CLRSD] is," Rush said. "Not only does it benefit the county, but it also benefits residents in terms of not having to worry if it's going to be able to handle demand and last into the future."
But sewage treatment plants are usually big, costly endeavors, he said, and they aren't necessarily any cleaner than septic systems.
"There is data that shows [septics] can treat wastewater as well, if not better," Rush said. "And there is no unused capacity because people only have to build a system for their needs."
Valerie Prax, an educator with the University of Minnesota's Water Resources Center, said septics filter wastewater more naturally.
"You are using soil to treat the water, rather than chemicals with centralized sewer," she said.
Unfortunately, neither option can successfully remove pharmaceuticals or strong, bleach-based cleaning products, Prax said.
Both compounds are being found in increasing amounts in drinking water, with unknown long-term health effects.
Prax said there is a potentially huge, albeit unproven, risk with wastewater treatment facilities.
Many communities across the country rely on ground water as their primary source of drinking water, she said.
This ground water often comes from aquifers - large freshwater reservoirs formed over many years and located deep underground.
More and more researchers are worried that because of how water flows through centralized sewer systems, these facilities might be stealing ground water from the system without replacing it, Prax said.
"If you hook into a pipe system, your cleaned wastewater is surface water discharge," she said, "which means it goes into a creek or stream, and not back into the ground.
"If you take [water] out and never give it back, that's got to be a problem some place."
The concern is that aquifers are that place, Prax said, and if they dry out, it could lead to massive water shortages.
Greg Kruse, supervisor of water monitoring and surveys for the Minnesota Department of Natural Resources, said based on what he's seen, it hasn't been much of an issue for the state so far.
"We are looking into it as part of a broader assessment," he said. "We don't have any areas pinpointed as areas of concern."
Loaded with upfront charges, centralized sewer generally costs significantly more than an onsite system, Prax said, but they also tend to last longer and are easier to maintain long-term.
"It does happen where people don't properly maintain [their septic tanks]," she said, "and when that's the case, it is worse than sewer."
Onsite systems can also take up a lot of room, which can be a problem for those with smaller properties, Prax said.
"That's where pipe may be a better option," she said.
Rush said many people forget how much space a septic system can take up.
"A 10,000 square-foot lot starts to get pretty small when you have to put in a 30-foot by 50-foot mound two or three times on there," he said.
Pam Meyer, an MPCA municipal engineer who reviewed the proposed CLRSD facility, said it can be a tough situation when some people in a community have enough land for a septic system, but others don't.
Without sewer, those lacking space then must use a holding tank, which is very costly, she said.
The bottom line, Meyer said, is that every community needs to decide for itself which wastewater treatment option is best for it.
"Both work well, and in our view, both are proven methods," she said. "It's a local decision."