The Missouri River stretches more than a quarter-mile from shore to shore here, its muddy water the color of coffee with a shot of cream.
The river carved this valley hundreds of thousands of years ago, and in the 1830s, it deposited the German settlers who founded this city. Today, visitors who sip local wine in hillside gazebos can gaze down at the water and imagine being on the Rhine.
For two centuries, Hermann has been known for the Missouri River – and now the river is making Hermann known for an unexpected reason: It is a hot spot for nitrate.
Washing off farms and yards, nitrate is largely responsible for the Gulf of Mexico’s infamous ‘dead zone.’ Nitrate and other nutrients from the vast Mississippi River basin funnel into the Gulf, sucking oxygen out of the water and killing almost everything in their path.
via Dead Zone Pollutant Grows Despite Decades of Work: Scientific American.