Manure and Sinkholes

Our tourism-based county with scenic bluffs and panorama unfortunately has the distinction of having a disproportionate number of sinkholes and open rock crevices that offer a direct conduit to our groundwater aquifer. We need to be especially careful to maintain the groundwater quality in a condition that reflects our future needs for clean unadulterated drinking water supplies.

Sevastopol town has the distinction of having the most known sinkholes, with more than 23 recorded sites, while other towns are following close with comparable numbers. The largest that I am aware of is west of Hwy. 42, near County P, and has been reported to have historically been the dumping location for junk farm machinery, animals, rubbish and an occasional Model T Ford. That should give you an indication of the size of the sinkhole. I hope we can assume that “dumping” has ceased at that site and no further degradation has taken place. Many sinkholes are not that large but all represent a threat to clean groundwater.

Nasewaupee town has an annual flowing stream that follows the County C road ditch, then disappears into a crevice in the rock only to reappear again at the surface more than a mile away. This type of groundwater attrition is possible in all areas of this county and is not limited to shallow soil areas. There are hundreds of groundwater access rock fissures and sinkholes scattered throughout Door County and probably many more that are yet to be discovered.

The recent problems with animal waste pollution only reinforce the fragility of our groundwater and the threats that come from all areas of human activity, from golf courses to homeowner wastewater to animal waste. These last episodes brought out the shortcomings of the Nutrient Management Plans for farmers that are the intended control and advisory method of placing animal waste where the nutrients are needed. As with any regulations, especially if they are voluntary, there will be individuals who will assume that the recommendations are flexible enough to allow variation from the plan.

Citizens have been urging tighter control over the animal waste spreading and calling attention to the violations for a long time, with weekend activity being most prolific. Hopefully the new, more restrictive Nutrient Management Plans will have real enforcement potential as a part of the agreement with farm operators, a factor that has been lacking until now.

Most farm operators in the past have followed the rules for animal waste use, but there are always those who deviate for their own benefit, even if it is shortsighted. Many of the same concerns can be made over setbacks from sinkholes and streams, whether intermittent or not, that seem to become narrower as each year passes, even though the proper setback was planned originally. I can understand how some farmers have a tendency to forget where their property lines are, but to put their own future groundwater in jeopardy by cheating on the setbacks makes no sense at all.

Residents and officials of Door County need to be aware that there will be a newly increased influx of manure hauling to the more remote areas of the county as the handling and control of animal waste spreading becomes more restrictive in Kewaunee County. This is already evident with considerable manure hauling from Kewaunee occurring in Southern Door and likely to expand to wherever there is cropland or vacant land available. Manure is currently being applied within the city limits of Sturgeon Bay. Spray irrigation or other liquid application are just two of the many options that manure haulers and farmers will use. Anyone being approached to lease out their land for manure spreading needs to be conscious of the liability that is shared by the landowner as the custodian of the property.