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Healthy Streams. BWCC Meeting May 13, 2013. Learning to Recognize the Health of your local stream. What is a Healthy Stream?. A Healthy Stream is a stream in it’s natural condition. …Water is clear, cool, odorless …Safe for people to swim and wade, for fish to swim in
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Healthy Streams BWCC Meeting May 13, 2013 Learning to Recognize the Health of your local stream
What is a Healthy Stream? A Healthy Stream is a stream in it’s natural condition. …Water is clear, cool, odorless …Safe for people to swim and wade, for fish to swim in Has a variety of physical characteristics throughout the length of the stream channel
Water Chemistry of a Healthy Stream: • Healthy Streams Have: • … chemical balance of enough oxygen for fish and aquatic life; enough nutrients from decaying plants and animal waste to feed on, but not more than what a healthy, natural stream needs • Water that is neither too acidic or alkaline (measured by pH) • No toxic chemicals from factories, farms and lawns washing into the stream
What Lives In & Around a Healthy Stream Healthy Streams Have: A Variety of creatures live in a healthy stream, using trees and shrubs along the banks as a food source The amount of water in the stream changes according to seasonality of the year, and the amount of rainfall and the biological life is adjusted to this seasonality Shade from the trees/shrubs on the streambank keep the water temperature stable, this streambank (riparian) habitat is essential for many fish and wildlife species
What Lives In & Around a Healthy Stream Recent Fish Survey (April 2013, from River Road downstream to Willamette River):
Physical Characteristics of a Healthy Stream: • Healthy Streams Have: • A Variety of physical channel characteristics • - fast flowing areas are called riffles • - deep pools • - quiet water glides • - logs, boulders, undercut banks provide variety of channel physical characteristics • Sediment input is balanced and not harmful to the stream; balance of sediment build up, and sediment scour, throughout the length of the stream. • Stream alignment curves and ‘meanders’, there are very few naturally straight streams
Stream Habitat Typing RIFFLES: Actively Moving Water Ripples or Whitewater easily observed Water movement increases Dissolved Oxygen levels GLIDES: Smooth water surface “mirror like” Smooth streambed No water movement prevents oxygen mixing POOLS: Form downstream of strong glides Generally at least 3+ feet deep in small streams
Boardman Creek (Then) 1851 US Surveyors Map (thanks to Pat Kennedy for providing this document to OLSD!) Stream Channel down to the Willamette River
Boardman Creek (Now) 2013 Aerial Photo Boardman Basin Source: Google Boardman Wetlands is only remnant of ‘bottomlands’ Conversion from wetlands to channel
Boardman Basin Plan • Seeks to find ways to re-naturalize Boardman Creek, recognizing the extensive land use within the basin • Some state and federal requirements to do this. • Is undertaking a variety of efforts to address water chemistry problems, such as low dissolved oxygen, toxic chemicals, and bacteria, all of which are serious problems for the water in the creek. • Required by state and federal laws
Boardman Creek Improvement Project Which brings us to the project at hand. The project team is looking for opportunities to restore as many of the natural functions of Boardman Creek at this location as we can, within some real constraints (cost and land availability, for example). Today’s presentation will take us through the progression of data collection, engineering evaluations, and different natural channel alignment options that have been considered. This project focuses on changes we can make to the physical characteristics of the stream, which will drive improvements in water chemistry and biological potential.