When Congress passed the Clean Water Act in 1972, it regulated sewage produced in our houses and businesses. It did not regulate water that washes off our streets and farm fields. What washes off our farm fields in the Midwest ends up in the Gulf of Mexico. Freshwater is lighter than salt water. When it flows to the gulf, it floats on top of the salt water. Normally, gulf winds stir the two together, but, setting aside hurricanes, summer winds in the Gulf are light and the stirring does not happen. Algae bloom in the freshwater, dies, and decays, sucking the oxygen out of the water, creating a Dead Zone, a low oxygen zone that fish, which swim cannot cross, and kills fish that cannot.
Yesterday, the U.S. Department of Agriculture and the Natural Resources Conservation Service announced that the agencies will provide $325 million over four years to farmers in Arkansas, Kentucky, Illinois, Indiana, Iowa, Louisiana, Minnesota, Mississippi, Ohio, Tennessee, and Wisconsin. This will help the farmers implement conservation measures to retain nutrients, nitrogen and phosphorus fertilizers, in their fields, keep the runoff out of the Ohio and Mississippi and therefore out of the Gulf of Mexico. The dense stand of trees that lines both sides of Hieser Slough, which runs between Iowa farm fields and the Mississippi, soaks up nutrients, which might otherwise flow to the Mississippi and the Gulf of Mexico.
Many farmers plow and fertilize their fields right up to the edge of sloughs that run through their fields, allowing nutrients to run directly into the slough and then to the river. The narrow, broken lines of trees, like that which lines Fish lake, are not enough to absorb the nutrients that farmers spread on their fields.
In addition, farmers have laid drain tiles under their fields to to lower the water table and speed water off their crops. In this way the roots reach down deep to the lowered water table during the dry season, making for stronger crops. During the Flood of 1993 hydrologists were stunned at the speed with which all that rain that fell on the Mississippi Basin drained off the tile-drained fields, in the uplands and the bottomlands, and to the river. Finally, streams like Fountain Creek, which gather water and nutrients from the uplands and flow across the Mississippi floodplain, are channelized between levees from their exit from the uplands to the river. They gather deliver their water and nutrients directly to the river.
In Illinois and Iowa Trees Forever is taking applications from farmers, who want to participate in the Conservation Buffer Demonstration Project, which seems to be a separate project from the USDA project. Farmers can receive up to $3,000 to build riparian buffers along the streams that edge their fields, bio-retention cells, and rain gardens. The funding for this program comes from a National Fish and Wildlife Foundation grant to Trees Forever.