Scott Kudelka, communications coordinator for the Minnesota River Watershed Alliance, said all conservation groups are particularly nervous about the effects of agriculture now because of record-high prices for grain.

“The biggest worry now is that a lot of the land in conservation programs is being pulled out. We’re going to lose a lot of that marginal conservation land. Farmers need to make a living and we have a big demand for corn,” Kudelka said.

In the Dakotas, land is being pulled out of grass cover and put back into crop production on a massive scale. “They’re losing 50,000 acres (of conservation land) in a lot of counties.”

More land in crops means more water moving quickly to the river. And with farmers planting more acres in corn — which needs more nitrogen fertilizer than other crops — there is more concern about nitrogen being carried into the rivers.

Kudelka said there has been a drop in phosphorus and fecal coliform levels in the river because of new city sewage treatment plants and upgrades to septic systems.

“Unfortunately, we haven’t seen much reduction in nitrates. They’re coming from nitrogen in farm fertilizers, and from cities and golf courses.”

Kudelka said it’s important not to blame farmers as being careless or unconcerned.

“Farmers are just trying to maximize their production and profits. They need nutrients. They are getting better. There’s a high cost to fertilizer now, and they don’t want to use any more than they have to.

“But with all the tile lines, nitrates are water soluble, and they go with the water.”