Hydrologist says people in rural subdivisions are drinking their neighbors’ septic tank water
PROTECTED CONTENT
If you’re a current subscriber, log in below. If you would like to subscribe, please click the subscribe tab above.
Username and Password Help
Please enter your email and we will send your username and password to you.
By LeAnn R. Ralph
MENOMONIE — Do you know where your well water comes from?
Neil Koch, a retired hydrologist, says in rural subdivisions in this area with private wells, within a few years of drilling the well, people are drinking their neighbors’ septic tank water.
Koch, who also serves as a supervisor on the Menomonie Town Board, was a member of a panel invited by the League of Women Voters of the Greater Chippewa Valley to speak on the safety of land-spreading septic tank waste at the Dunn County Judicial Center the evening of February 28.
Other members of the panel included Lindsay Olson, Dunn County water quality specialist; Paul Sterk, City of Menomonie wastewater superintendent; Bob Colson, Dunn County zoning administrator and planner; and Mark Leach, ecologist.
The idea for the forum came from the League of Women Voters’ environmental study group. The League of Women Voters has several different study groups.
About 75 people attended the forum.
In rural subdivisions where the houses are relatively close together with a density of one house per acre, 60 percent of the well water comes from neighboring septic tanks, Koch said.
In an area near Oshkosh, septic systems were abandoned because they were contaminating water wells, he said.
And yes, in Koch’s opinion, land spreading of septic waste is a health hazard because it contains bacteria, viruses and various kinds of chemicals, such as pharmaceuticals and cleaning chemicals.
Michigan, Florida and parts of Iowa have banned land spreading of septic waste all together, he said.
There are more than 400 sites in Dunn County where the state Department of Natural Resources has issued permits for land spreading, but 150 of those sites do not meet DNR requirements for percolation of no more than six inches per hour soaking into the ground, Koch said.
During his portion of the presentation, Bob Colson, Dunn County zoning administrator and planner, noted that a septic spreading “site” can be a 40-acre or 80-acre parcel.
Urban sprawl is a major cause of increased nitrates in well water, Koch said.
High nitrates in well water can cause a variety of health problems, including “blue baby” syndrome, thyroid ailments and colorectal cancers, he said.
Nitrate testing should be done in housing developments, and where the nitrate level is high, the houses should connect to a municipal water system or the area should establish a rural water system, Koch said.
Research has shown viruses can travel a long way in groundwater and can stay alive a long time, he said.
One-half
People with water wells in Dunn County get their water from sandstone aquifers, said Olson, Dunn County’s water quality specialist.
The average depth of water wells in Dunn County is 125 feet, and half of the people living in Dunn County live outside of an incorporated area and have their own private wells, she said.
Nationwide, 11 percent of the population have private wells and 18 percent use a septic system, Olson said.
Private wells can be contaminated with nitrate, bacteria, agricultural chemicals, heavy metals and pharmaceuticals, she said.
In Dunn County, 15 percent of the wells exceed 10 ppm of nitrate, Olson said.
Nitrate can contaminate wells because of the over-use of fertilizer, because of septic tanks and because of natural deposits, she said.
Well water can also be contaminated with micro-organisms such as bacteria that cause gastrointestinal illnesses, Olson said.
Treatment
The Menomonie wastewater treatment facility does accept septic tank waste and holding tank waste, said Sterk, the superintendent of the Menomonie wastewater facility.
About 1.5 million gallons per day goes through the wastewater treatment plant, he said.
The plant has 2 million gallons of storage capacity, and it is at 52 percent of design capacity, Sterk said.
The cost for dumping septic tank waste is $114 per 1,000 gallons; the cost for holding tanks is $8.50 per 1,000 gallons, and portable toilets are $25 per 1,000 gallons, he said.
Mapping
Wisconsin’s Chapter NR113 requires licensed septic haulers to land spread septic tank waste, said Colson, Dunn County’s zoning administrator and planner.
Regulations also require land spreading to be done on nothing more than a 2 percent slope; allows 10,000 gallons per acre; does not allow spreading on wetlands; does not allow spreading within 750 feet of a waterway; and does not allow spreading on snow or frozen ground, he said.
There are 35 licensed haulers in Dunn County, and there are 493 accepted septic spreading sites in the county, Colson said.
At one time, Dunn County had tried to map the licensed septic spreading sites to compare to a map of environmentally sensitive areas, he said.
The county had asked the state for some map information, and it had taken someone on the state level 16 hours to produce one section of the map, and it took a Dunn County employee another 11 hours to map the septic spreading sites for that section, Colson said.
Based on the amount of time it takes for mapping, one person would have to work 40 hours per week for four years to map the septic spreading sites in Dunn County, he said.
Comments
One person in the audience wondered if it would be possible to have rural wastewater treatment plants, set up similar to a fire district, to treat the contents of septic tanks and holding tanks.
Community manure digesters are used in southern Wisconsin, Olson said.
The idea of community manure digesters is a topic that should have more discussion in Dunn County, she said.
One gentleman in the audience noted that over the past eight years, the governor and the state legislature have severely weakened the DNR.
The DNR has been “cut off at the knees,” and that’s one reason why counties need more local control, Colson said.
In many instances, counties are not allowed to be more restrictive than the state, such as in the area of regulating land spreading of septic waste or shoreland ordinances, he noted.
Local control has been taken away, and counties should be able to apply standards that are more restrictive than the state when necessary, Colson said.
Nitrate surveys
Ken Schmitt, a Colfax resident who lives in Chippewa County, noted that groundwater surveys of nitrates in wells in Chippewa County in the late 1980s and again in 2007 and 2016 showed the same number of increase of wells contaminated with 10 ppm of nitrate between 1980 and 2007 and between 2007 and 2016.
It is the same number of wells — but in less than half the time — so the rate of nitrate contamination is accelerating, he said.
Local groups need to “bang on legislative doors,” Schmitt said.
Mound systems are not particularly helpful, he said, because a mound system puts the nitrogen deep into the ground beyond the roots of plants that could use the nitrogen.
Awards
Kathy Stahl, also a Colfax resident, suggested that a list should be available of septic haulers who take their loads to wastewater treatment plants instead of land spreading.
And those haulers who go to wastewater treatment plants should be “given awards for doing the right thing,” she said.
Legislator
Cheryl Miller, clerk for the Town of Red Cedar, announced that Rob Summerfield, the representative for the state’s 67th Assembly District, would be holding a listening session at the Red Cedar Town Hall on Monday, March 25, from 1 p.m. to 2 p.m.
People attending the forum should bring their concerns and ideas to the listening session with Representative Summerfield, Miller said.