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..,Continued from page 6 riparian vegetation; increased water temperatures; wetlands drainage and decreased aesthetic quality. A five man crew has been hired to do the work on the Cottonwood River project. The crew consists of a heavy equipment operator and four laborers. Equipment required for the work includes: a tractor, backhoe or dozer; 2 - chain saws, logging chains, steel cable, steel fence posts and lots of elbow grease. Logs are pulled from the channel with the use of tog- ging chains and a dozer. Once removed from the channel the log piles are either burned or secured in an area away from the immediate floodplain. If debris piles are left in the flood plain, they are cabled down to prevent re-entry into the stream during the next flood event. Preventative channel maintenance is performed during the clear and snag phase. Unstable overhanging trees and limbs are cut at the base, leaving the root structure to pro- tect and the riverbank. Stable trees and limbs are left to provide shade for the stream. Single logs, not considered a significant obstruction to flow or to be a source of erosion, are not removed from the channel but are left for fish and wildlife habitat; .~Once the major log jams have been removed from each river segment, the bank stabilization process is initi- ated. Generally speaking, banks most suitable for tree top protection are those' which are located on the outside curve of a river meander where the current is being deflected into the streambank. In situations such as this, a pointbar usually forms directly opposite from the eroding bank (See Photo #10). As the pointbar grows, increased erosive force is applied to the opposite bank. Tree tops are placed along the eroding bank and an- chored to it using steel cable anchored to steel fence posts or any other fixed object. Live tree tops are preferable be- cause of their greater resilience to damages associated with impacts from flood flow. The protected bank acts to deflect the current while the treetop structure slows the water ve- locity in the immediate area, causing sediment to drop out and eventually a sandbar to form, thus, "letting the river do the work" (See Figure #2).. TREE TOPS Eroded [ Bankon POINT Outside BAR Curve ANCHOR POIt FIGURE 2. Application of '3=almiter Method" This schematic shows a typical point bar formeti~ directly ol:)posite the outside curve of the stream meander. Proper application of the Palmiter Metho(t at the opposite bank will reduce bank erosion and size of the point bar. Trees are anchored with cabte to I'ixe(:l points on shore s~3 that the"butts"of the tree trunk face upstream. Placement of the treetop structures is critical, requlr- lng a basic understanding of river hydraulics and more im- portantly, field experience. If the structure is not located properly, it may cause additional erosion problems. Following sandbar formation, the protected banks are revegetated with cuttings from shrubs and trees indigenous to the area. Work is usually done in the late summer or fall during low flow conditions. The Cottonwood project was not started until December of this past year due to our unusu- ally wet fall. Conditions proved to be ideal this winter due to mild temperatures and a lack of snowfall. Disturbance to the banks and adjacent floodplain was negligible because of frozen soils. Water resource planners and managers in southwest- ern Minnesota will be closely monitoring the results of this winters work. Interest is high because, ff successful, the method being tested provides an economical and more envi- rommentally acceptable means of restoring the flow of our rivers and streams. Minnesota's streams and rivers have been a neglected resource in the past. The rath of Dutch Elm disease in combination with 5 to 7 years of higher than normal stream flows have left hundreds of miles of river resource in a clogged, obstructed condition. The Palrnlter Method has been used successfully in In- diana, Ohio and North Carolina. In recent years Indiana, alone, has spent over $1 million for projects using this method. Another $910,000 in projects are now in the plan- ning phase. Debra Chelm, River Planner for the Indiana Depart- ment of Natural Resources has had lots of experience with application of the methodology. Debra said in a recent in- terview, 'some people have been lead to believe that the method will reduce flooding. We feel that it (the Palmiter Method) will lower the level of small, more frequent floods. Major floods like the 25, 50 or 100 year floods will not be impacted much.' When explaining the program to groups, Debra alludes to the following benefits of this method of river restoration: · maintains or improves local drainage. · reduces channel bloc 'kage · reduces erosion and sedimentation · improves boating and canoeing conditions · improves aesthetic quality of the stream For more information concerning the Cottonwood River Project contact Bob Finley, RCRCA Coordinator in Redwood Falls (507) 637-2142 or Skip Wright, DNR Area Hydrologist (507) 354-2196 in New Ulm. Editor's Note: The author, Art (Skip) Wright is our Area Hydrologist in New Ulm. Skip has a Masters Degree in Water Science from the University of V}qsconsin, Stevens Point. Prior to starting with DNR, DOW in 1984, Skip worked for the Wyoming Department of Environmental Quality. "Water Talk" is published by the Minnesota Depart- ment of Natural Resources, Division of Waters. Editor: Bruce Sandstrom Graphic Arts: ,Jim R. Zicopula I