Getting a local handle on nutrient loss

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he Illinois Nutrient Loss Reduction Strategy (INLRS) calls for a 45 percent reduction in nitrogen and phosphorous nutrients being lost to the Mississippi River to address the Dead Zone in the Gulf of Mexico. Jo Daviess County is not exempt–we should do something (especially if we want to avoid additional regulation). Where do we start?

Locally, two questions come up again and again: “How do we know what our nutrient loss levels are?” and “Our rivers start north of the state border –how much of the nutrient problem is coming from us and how much is coming from Wisconsin?” Finding answers to these questions is difficult and generally expensive (an unhappy combination!). The League of Women Voters of Jo Daviess County has been wading into this dilemma. Each bit of information gathered is like a pixel–little by little we hope to get a clearer picture so we can take practical, cost-effective measures. Here is what we know now:

With generous contributions from the city of Galena, the U.S. Fish & Wildlife Service, East Dubuque Nitrogen Fertilizers, Oak Lodge Foundation, The Galena Lions and Grace Episcopal Church, the League was able to work with scientists from the University of Illinois to conduct a down-and-dirty assessment of nitrogen sources in the lower Galena River (see scientists’ presentation at https://bit.ly/2HMHaZ6). Gathering samples from the main trunk of the Galena River and from the tributaries flowing into it, lab analysis was conducted to determine if nitrogen in the water came from fertilizers, animal waste and/or human waste.

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The results suggest that the nitrogen in the river is due to a mixture of sources that are dominated by manure and/or septic effluent with lesser amounts of fertilizers. It appears that human septage in all areas of the river is a significant component warranting concern. We also noted a decrease in the nitrate concentrations as we went down river, documenting that higher nitrate levels at the top of the watershed were being diluted as they moved through the watershed.

The League received a $30,000 grant from the Illinois Environmental Protection Agency for a “Nutrient monitoring on the Galena River” project. The U.S. Geological Survey is contracted to take 16 sets of samples from the Galena River just below the Wisconsin border and at the bottom of the Galena River watershed where it flows into the Mississippi River over the course of a year.

The samples will be analyzed for a complete suite of nutrients (nitrate and nitrite, ammonia, organic nitrogen, total nitrogen, dissolved phosphorous, total phosphorous, and orthophosphorus) and suspended-sediment concentrations. This information will provide some clarification regarding the nutrient and sediment contributions within the Illinois portion of the Galena River watershed. We may be able to thoughtfully extrapolate this information to other areas of the county.

These projects don’t provide complete answers, but they do give us good reference points to guide our efforts going forward.

With questions, contact Beth Baranski at beth@bhms-arch.com or 563-580-6192.

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