Wild Side: Flowing out of sight, not out of mind
In 1869 the German zoologist Ernst Haeckel defined ecology as the study of the "house" (based on the Greek oikos), as a body of knowledge about the economy of nature, the interactions between the organic and inorganic environments.
Economy is defined as the efficient, sparing or concise use of something, and the management of the resources of a community or country especially with regard to the services provided by ecosystems. What we perceive as a resource or a non-resource in a given place and time is about an economy of survival.
Our aesthetic sense of place is grounded in the ecosystems that we inhabit, sharpened by the understanding of what it takes to keep us alive.
Our sense of the beauty of the western Wisconsin landscape is stimulated by the presence of water that supports verdant crops, grasslands and forests, flowing streams and lakes. Clean water is without question an important resource.
We are blessed with an abundance of clean water here in western Wisconsin. Drill a well almost anywhere and you can pump out lots of clear, clean water. It's easy to become complacent about that remarkable resource due to its relative abundance here in contrast with other parts of the world.
Rapid residential and agricultural development in central St. Croix County raised concern about water resources. What would be the effect of new municipal and irrigation wells on the groundwater aquifer and flow of the Kinnickinnic and Rush Rivers? What might be the effect of large municipal wastewater lagoons on ground water quality?
What must be done to protect groundwater quality and residential and municipal water supplies?
Encouraged by Trout Unlimited and the Kinnickinnic River Land Trust, the staff and boards of Polk, St. Croix and Pierce counties supported a study of the groundwater flow system in the three counties. The study was conducted by the U.S. Geological Survey Wisconsin Water Science Center with assistance from the counties, the DNR, the university system, and the Wisconsin Geological and Natural History Survey.
The report by Paul Juckem, "Simulation of the Groundwater-Flow System in Pierce, Polk and St. Croix Counties, Wisconsin," was released in September and is available on-line at: pubs.usgs.gov/sir/2009/5056/. The report is rather technical but it describes development of a regional groundwater model making use of a wealth of existing information about the geology, hydrology, and water use in our area.
Groundwater is the sole source of residential water supply in Pierce, St. Croix and Polk counties. Groundwater sustains area lakes, streams and wetlands. The groundwater aquifers that we rely on are in glacial sand and gravel deposits in the northern part of the 3-county area, and in permeable limestone, sandstone and shale bedrock.
Our aquifers are vulnerable to contamination from the surface, as is indicated by locally high nitrate concentrations in groundwater samples.
This area receives an average of about 32 inches of precipitation annually. The regional groundwater model indicates that 82 percent of the groundwater in the three counties was from recharge from within the counties, 15 percent was from surface-water sources and four percent was from inflow across county boundaries.
Approximately 85 percent of groundwater flow out of the counties was to streams, 14 percent outflow across county boundaries, and one percent to pumping wells.
The groundwater table elevation in the three counties generally follows the surface contours of the land. Groundwater flow is mainly into tributary rivers and to the St. Croix and Mississippi rivers.
Last summer's dry weather resulted in little recharge of groundwater in our area and stream flows reflected the near-drought condition. Although our weather in October was unpleasant, the additional water has helped make up our water deficit. There was enough rainfall recently to saturate soils, produce surface runoff and increase stream flows again.
The water added to our groundwater system will be available for us to drink. It will sustain the base flow of the trout streams and will keep our landscape productive and beautiful.
We should be mindful and protective of that wonderful resource that flows slowly beneath our feet.
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