Life Depends on Water how streams work

How Streams Work

Natural Stream Ecology	Altered Stream Ecology
		Urban Stream Dynamics
			Channelized Streams
			Dams

	Natural Stream Ecology
	Natural streams have not been substantially altered or manipulated by humans. Natural streams are dynamic (always changing) and perform many beneficial functions. They transport water and sediment, they temporarily store excess floodwater, they trap excess sediments and pollutants in stream banks and riparian areas, they recharge and discharge groundwater, and provide necessary and supportive habitat for diverse plant and animal species.

The shape of natural streams is varied. Meanders or winding paths is common. Meanders increase a stream’s length and absorb excess flow in storm events and create diverse habitats for animals and plants in the stream community.

Natural stream characteristics:

• in-stream submergent and emergent aquatic vegetation

• pool, riffle and run habitat, riparian vegetation on stream banks

• varied stream bed substrate or surfaces including organic materials, sand, gravels and boulders.

Snags or large woody debris are important to natural streams. Often times, landowners want to rid their streams of downed trees and woody material, but they provide important ecological functions to the stream.

Streams with a good amount of large woody debris tend to have greater habitat diversity, a natural meandering shape and greater resistance against flooding and high water events. Trees that have fallen in or near the stream provide shelter and habitat for insects, birds, and small animals while certain fish utilize the shade for protection and camouflage for hunting.

For additional information please see the
O hio Department of Natural Resources Stream Management Guides



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