By Jason Rice
They’re not exactly the stuff of polite dinner conversation, but septic systems are a prime topic for Lake Superior region homeowners.
Septics, or on-site wastewater treatment, are common lakewide, especially in rural areas, which means that homeowners and home buyers must tend to their wastewater rather than tapping a municipal sewer system. Rural areas around the lake average from 50 percent to almost 100 percent use of septic systems as is the case in Douglas County, Wisconsin. Some shore areas in Minnesota are at 80 percent and growing, reports the Natural Resources Research Institute at the University of Minnesota-Duluth. The NRRI has worked with system innovations.
A study by the Western Lake Superior Sanitary District (WLSSD) estimates that more than 50 percent of the district’s septic systems are failing.
That’s a lot of people with a mess in their back yards, made more alarming if those yards include shoreline. Indeed, so many septic systems were failing along a stretch of Minnesota’s Highway 61, which follows Lake Superior from Duluth to Two Harbors, that the whole area is being converted to city sewer, obligating homeowners to foot the huge cost.
Jeff Crosby, a sanitarian with the St. Louis County Department of Environmental Health, advises not to be panicked by system “failure” statistics if you own a home with a septic or are looking to buy one. It’s not as murky a situation as all that, says Crosby, who questions the word “failure” in those reports.
“Real septic failure that constitutes a public health issue is only about 3 percent,” he says.
Crosby says some functional, working septics have been labeled as “failing” because they do not comply with new codes, not because they constitute environmental or public health problems.
Septics that truly fail do so for a variety of reasons. Some are just old. Septics generally work for 20 to 50 years. Others are poorly maintained or shoddily installed. And lastly, our northern terrain can cause problems.
The prevalence of shallow bedrock, a shallow water table and high-clay soils all are familiar landscapes for Lake Superior’s northern and western shores and all spell trouble for traditional septic systems, says Rich Axler, a senior research associate with the NRRI.
You need soil and lots of it for traditional septic systems like trenches and mounds, and you’re in trouble if your property doesn’t have it.
Axler’s former NRRI colleague, Barbara McCarthy, now an expert on wastewater treatment for Minnesota Pollution Control Agency, notes the problem of seasonally saturated soil. “Septics need air. If they don’t have it, they don’t work properly.”
Not just northern shorelines are troublesome. In Wisconsin’s Douglas County, high-clay soils necessitate holding tanks. In Michigan, sandstone presents the same problem as northern rock – not enough soil, says Fred Benzie of the Marquette County Environmental Health Department. “The shoreline can be environmentally challenging for people who need to put in septic systems.”
Code-compliant septic systems concern homeowners and buyers. Minnesota’s St. Louis County now requires septic systems to be brought into compliance before they are sold.
What many of those homeowners don’t know is that alternatives exist to traditional trench and mound systems, ones that provide creative solutions to terrain problems.
Gene and Barb Curnow credit a new system with saving their lake. In the early 1990s, Curnows bought a cabin in Minnesota on Grand Lake – a slice of North Country heaven. They decided to turn the cabin into a home.
That’s when they discovered what other lake homeowners have learned: failing, aging septic systems were slowly tainting their lake.
“When you bought or remodeled a house out here, you were ‘grandfathered in,’ meaning, you just used what kind of septic was there,” Gene Curnow says. “But the septic systems were old and leaky and the wastewater wasn’t getting cleaned. It all ended up in the lake.”
Fish populated the waters, but the septic situation still endangered the water quality of Grand Lake.
Many area homes were experiencing true septic failure, a serious environmental and public health threat that needed fixing – fast.
The problem was the terrain. The native soils are saturated with water much of the year … a recipe for disaster for septic systems. One family’s brand new mound system literally sank into soggy ground.
“Today we probably wouldn’t allow a development on land like that,” says Barb McCarthy, who worked on the solution for this area. “The houses and cabins on the Triple Lakes Road (where the Curnows live) is really a wetland. Basically, a swamp. It’s very difficult to build on and it’s hard to put utilities and roads in. In today’s land use practices we wouldn’t see this as a buildable place.”
Yet families already had homes and property on that “unbuildable” place. They needed a creative alternative to their septic problem.
The NRRI found it in the form of a “constructed wetland” system.
Constructed wetlands are marshy areas that receive the effluent (wastewater with solids removed) from septic systems and cleanse much of the water’s impurities through natural filtering by aquatic plants and a rocky gravel bottom. Cattails and bulrushes, common to our area, are two of the green players in the process.
The wetland ponds in this system look like any other swampy area, and on a large scale these engineered swamps can handle the wastewater of a whole cluster of homes.
Barb McCarthy was a wastewater researcher with NRRI when Grand Lake became her first experience in planning a constructed wetland.
