How does runoff from urban and agricultural areas affect marine life in the Chesapeake bay?

Urban runoff significantly impacts the Chesapeake Bay by introducing pollutants like sediment, nutrients, and chemicals into the water, ultimately harming the Bay's health and ecosystem. These pollutants come from various sources in urban areas, including roads, rooftops, parking lots, and construction sites. 

The nutrients and nitrogen fuel the growth of algae blooms which create low-oxygen dead zones that suffocate marine life.

Agricultural areas affect the Chesapeake bay since some agricultural practices—including over-irrigating farmland, over-tilling soil and over-applying fertilizers and pesticides—can push pollution into the Bay and its local waterways. Agriculture is the single largest source of nitrogen pollution entering the Chesapeake Bay.