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The result is that such a river will accomplish radical adjustment to extreme events by complete changes of channel configuration. Such radical charmel changes may substantially affect development well outside the delineated 100-year floodplain. For this reason, "erosion buffer limits" were established to protect man-made structures from the instability of the river system and to minimize the influence of maIl'S activities On the acceleration of the channel response. The following reports include channel stability anltlyses aIld erosion buffer limits; 1. Final Report, Fossil Creek Stability Study, Trilby Road to Lemay Avenue, prepared by Lidstone aIld Anderson, Inc., dated October 1992. 2. Mail Creek Stability Study, prepared by Lidstone and Anderson, Inc., dated JaIluary 1993. 3. Final Report for Stanton Creek Stability Study, prepared by Lidstone and Anderson, Inc., dated May 1993. 4. Channel Stability Analysis, Bums Creek ilhd Fossil Creek, Clarendon Hills Development in Fort ColIins, dated September 1991. 5. Fossil Creek Drainage Basin Master Drainageway Planning Study, prepared by Simons, Li, and Associates, dated August 1982. 6. Cache La Poudre River Master Drainageway Plan, prepared by Resource Consultants Inc., in review. 7. Fossil Creek Stability Study, Huntington Hills P.D.D.- Lemay Avenue to College Avenue, Lidstone and Anderson, Inc. In r€:view. The purpose of the Fossil Creek Basin stability studies are to; I) characterize the stability of the respective streams based upon an evaluation of hydrologic, hydraulic, geomorphic and sediment- transport characteristics of the stream basin aIld develop practical improvements for mitigating adverse impacts on the streams; 2) develop design criteria aIld construction standards for improvements in natural drainageways, with regard to reach stability, within the City of Fort Collins; and, 3) establish erosion buffer limits alcmg the study reaches. The Poudre River Master Plan also addresses ch<mnel stability along the Poudre River. The stability analysis was conducted to determine the overall condition of the main river channel and identify erosional or depositional trends that may adversely affect properties within aIld adjacent to the 100-year floodplain. The results of the aIlaIysis indicate that the existing charmel is relatively stable vertically, but exhibits a strong tendency for lateral migration by erosion of the channel banks. The field inventory conducted by RCE Inc. (1994), indicates that approximately 40 percent of the total length of the main channel banks are either actively eroding or have been protected from erosion using riprap, concrete rubble, or other techniques. 24