Several projects of the Michigan Wildlife Conservancy, including restorations of Bigelow and Martin Creeks in west Michigan, are aptly demonstrating cost-effective ways to improve streams as fish habitat. Although many variations in methods are being employed in the Newaygo County streams, most are based on structures described in “A compendium of 45 trout stream habitat development evaluations in Wisconsin during 1953-1985,” by R.L. Hunt of the Wisconsin Department of Natural Resources.

The “triangular wing deflector” is extremely useful in restoring meanders (bends) and deep, swift pools. They are placed along the inside of stream bends or used to restore meanders in stretches made straight by channel erosion. They vary in size and shape, but in the Bigelow Creek Project typically are 15 feet across at their widest point and 20-50 feet long. Each wing deflector requires 5-10 cubic yards of fill. In Bigelow Creek a few of the deflectors are made of woody debris found in the stream, but most include at least some rock.

Bank covers are used mainly on the outside of stream bends to protect the bank from erosion and provide “overhead” trout cover. They are substitutes for undercut banks—an important natural trout cover. Typical construction involves embedding pairs of wooden pilings in the stream bottom with the help of a “jet” pump. A top-deck is then added and covered with rock and sod. Like deflectors, bank covers narrow the stream channel and thus help speed the current.

Lunker structures are a prefabricated type of bank cove, constructed in a standard size, transported to the stream, and joined together at each structure site. As used in Bigelow Creek, they are built from white oak lumber in 8-foot-long sections 3-4 feet wide. Each section costs about $120 to build and, because of its weight, is taken to the installation site in three or more pieces. Otherwise, heavy equipment is needed to install each section.

Brush bundles are usually placed on the inside of bends to act as deflectors and help narrow the stream. The brush bundles are made of brush cut along or close to the stream, and are anchored to the stream bottom with wooden stakes. Anchoring chords are also needed at many sites. Downed or felled trees of various sizes are often installed along with the bundles to increase stability during and after construction. Although not as durable as rock or wood-armored wing deflectors, brush bundles are inexpensive to install and in some stream stretches more cost-effective. They can be very useful in “filling” rock-based triangular wing deflectors during construction as they trap sediment.

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