Cooper Creek above Ashcroft to Conundrum Creek
The upper segment of Castle Creek is characterized mostly by high quality riparian areas and only slightly degraded in-stream habitats. This high elevation stream flows through landscape that alternates between narrow steep canyons where spruce-fir forests dominate and wide, flatter valleys where natural meandering increases stream sinuosity and where flooding flows spread out to recharge ground water. Wide willow carrs characterize these flatter valleys. Beaver activity has enhanced sinuosity and helped create a mosaic of open water, meadows in various stages of succession, thick stands of willow and occasionally conifers on higher, drier hummocks.

Threats to a healthy stream include:

• In the headwater region, which is primarily public land, recreation and roads threaten stream sustainability.
• Inappropriate development of private lands threatens the stream ecosystem throughout the valley;
• Altered flow regimes threaten riparian and stream functions and wildlife sustainability;
• Roads fragment wildlife habitat and create barriers to movement between upland and stream ecosystems, provide an invasion corridor for weeds, enable human disturbance into otherwise relatively pristine habitat.