The hand of humankind is much in evidence on the Mississippi, and we've left plenty of fingerprints over the last 150 years.

Humans have been impacting the river far longer than the recent past. The Mississippi was the primary transportation and trade route into and through the central part of the continent. People drank its water and sent their wastes downstream, as they continue to do today. People harvested the plants and animals that were abundant in the river valley. But until the advent of serious European settlement, there weren't enough people in the region to seriously affect the river. And with large numbers of European settlers came the need for reliability: a reliable source of drinking water, reliable water levels for transportation, reliable flows for flushing away waste, etc.

Humans have needed many things from the river, and while those needs have changed over time they have perhaps increased in recent years rather than diminished.

• A variety of water-based recreational activities have evolved and their impacts on the river are increasing, despite the fact that some uses are not compatible with each other nor with commercial transportation. And while commercial (barge, riverboat) transportation was here first, the ways in which it uses the river have continued to change, as well.
• As our population has increased, our need for clean drinking water has also increased.
• Population growth has increased domestic and industrial wastes. Some of those wastes are now entering the river farther upstream than ever before. As science better understands the long-term effects of some industrial wastes, we face new challenges.
• Urban development on the river's banks has changed over time as our perceptions of the river have changed. Today, some of the hottest properties in the metropolitan area have river views, and we face the challenge of loving the river to death.
• Floods and droughts are as old as the river itself, but as people creep closer to the water and make more demands on the river, natural flood and drought cycles have greater human impacts.