The Northern Great Plains form a large part of the Missouri River Basin (MORB), which is the “life zone” of the larger Mississippi River Basin.

WWF calls the MORB the life zone because it is made up of largely intact grasslands,

which help to infiltrate precipitation and reduce downstream flooding, filter nutrients (such as nitrogen and phosphorus), store carbon, recharge groundwater, reduce erosion and provide wildlife habitat.

Follow the flow of water from the Rocky Mountains into the Northern Great Plains, through the Missouri watershed into the Mississipi.