WETLANDS INTEGRATED HYDROLOGICAL ANALYSIS (WIHA)FOR WETLANDS PROTECTION AND PLANNING

The Cucumber Gulch wetlands complex, located near Breckenridge, Colorado, is currently being studied for proposed expansion of the Breckenridge ski area. The delineated wetland complex is a jurisdictional wetland and is protected under section 404 of the Clean Water Act. A wetland integrated hydrologic analysis (WIHA) approach was used to develop assessment tools for wetlands protection planning. These tools, designed around ArcView software, were used to integrate climate, topography, surface and ground water hydrology, geomorphology, geology, vegetation, and human activity data necessary to characterize the surface and groundwater hydrology systems that pertain to wetlands. A three-dimensional solid computer model of the surface and sub-surface hydrogeology was constructed. Through analysis and integration of these various data layers, surface and groundwater hydrogeologic and hydrologic system conceptual models were developed. The hydrogeology of Cucumber Gulch, on a watershed scale, includes the fractured crystalline Idaho Springs regional aquifer system that underlies and sustains the entire wetlands area. The unconsolidated surficial units, including glacial and fluvial gravels and peat, comprise the more local aquifer system that contains the wetlands, and are part of the interface between the wetlands and the surface water bodies. The sedimentary rocks located in the area, along with faults, serve as barriers to ground-water flow, and force the regional system to discharge into the shallow ground-water system, wetlands, and streams. The hydrologic system is recharged by infiltration of precipitation, and by snow making activities. Ground water is discharged by water moving into surface water bodies, and by evapotranspirtaion within the wetlands. The ground water flow patterns are from shallow to deep aquifers in the hill slope regions, and from deep aquifers into shallow aquifers and surface water bodies in the wetlands areas. WIHA provides the town of Breckenridge with long term planning and dissemination of public information through maps and displays.