Application of Hydrogeomorphic Concepts to Assess Riparian-Wetland Functions Affected by Road Construction in Southwestern Montana

The U.S. Army Corps of Engineers has been developing a hydrogeomorphic (HGM) approach for assessing wetland functions in the context of its Section 404 Regulatory Program. To date, the HGM approach has not yet been refined such that it can be rapidly applied, although regional guidebooks for its application are in progress. In lieu of a published guidebook, HGM concepts were used to develop a modified approach to assess riparian-wetland functions that would be affected by the reconstruction of Montana Forest Highway 73. Agencies participating in the Section 404 process adopted the modified approach and used it as a guide for determining the level of mitigation required to compensate unavoidable impacts to wetland functions.