Lesson 3 - How to Tell if a Creek is Healthy - Or Not!, Information Sheet
Acknowledgement: Taken from "Living on the Land 2001"

The potential of every creek is different. However, below are some signs you can generally use to tell if your creek is in reasonable condition or if something may be amiss. Creeks may be healthy and not exhibit all the signs listed below, or as little as one or a few of these signs may potentially indicate high risk.

Signs of a healthy creek:

• Water temperature is steady and water is clear and free of excess algae or odors. (What is right varies with the landscape setting)
• Natural variations in flow cycle
• Stable banks that have little erosion and the stream balances erosion with deposition and revegetation
• Areas of pooling water in slower stretches and fast-running water over shallow rocky areas
• A meandering stream channel (rather than straight, deeply-cut banks) in broad flat valleys away from mountains
• Ample room for creek water to spread out during floods. (What is right varies with the landscape setting.)
• Rock and gravel of sizes that fit the landscape setting
• Trees, shrubs or densely rooted herbaceous plants such as sedges and rushes that stabilize banks, provide habitat for wildlife and keep water temperatures steady
• A variety of native riparian (wetlands) vegetation, rather than monocultures (one type of vegetation), upland (dryland) vegetation or weeds
• Abundant varieties of fish, wildlife and aquatic insects
• Presence of some natural organic materials, such as leaves, branches and other debris, that support the aquatic food chain and provide hiding and breeding places for fish and other aquatics

• Poor water quality, evident from excessive algae, sediment, animal or human waste, or other contaminants that have been detected through lab tests
• High water temperature due to exposure to excess sunlight or unnatural low flows
• Reduction in water flows for extended periods of time
• Loss of the natural meandering creek channel (a straightened channel)
• Incising (downcutting) of the creek bed and large amounts of erosion along banks
• Uniform water velocity with an absence of pooling and fast water
• Deposits of fine sediment on the bed so that rock and gravel are covered or the spaces are filled
• Trash and debris in the creek that would not be found there naturally
• Too little coarse woody debris from trees to provide roughness, catch sediment or form pools
• A lack of diversity in the vegetation and animal species
• Banks that lack healthy riparian vegetation
• Monocultures (a single species), especially of weeds or other invasive species
• Lack of fish and other aquatic wildlife, or reduced populations
• High density of building in the floodplain surrounding the creek

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