There are many irrigation diversions all along the Poudre River below the mouth of the canyon. Most were designed and built years ago and did not consider the importance of fish passage in their design. As a rule, fish can only move or be swept downstream with the old style diversion structures. Once down, these fish are not able to move back upstream either because the structures are too high to jump or the water is moving too fast to navigate.
The Poudre Runs Through It has been exploring opportunities to help replace or modify existing structures to add upstream fish passage to diversions without affecting the irrigation company’s ability to divert their water rights, making these win-win projects for all involved.
In one case, it may be possible to combine two diversions into a single, better functioning structure: the B.H. Eaton and Whitney diversions just west of Windsor, Colorado. In another case, the North Poudre diversion into Fossil Creek Reservoir near the Environmental Learning Center in eastern Fort Collins was severely damaged by the September 2013 flood and has been rebuilt in a more ecologically friendly way. The redesign of both projects is being aided immensely using expertise from Colorado Parks and Wildlife, and with cooperation from Larimer County, Windsor, Fort Collins, Northern Water, the Colorado Water Conservation Board and others.
Trout and native fish such as dace, shiners, and stonerollers have been declining in population, in part due to habitat loss. The redesigned North Poudre diversion allows these fish to move upstream to repopulate habitats that may become available as conditions in the river change annually or through the seasons, or to seek refuge from non-native predators. Colorado Parks and Wildlife will be monitoring the effectiveness of the new fish passage facility and modifying it if improvements are necessary.
A "fish-eye view" video of the new Fossil Creek Inlet diversion structure showing how the fish passage incorporates specially fitted river rocks to dampen the water’s velocity may be seen here.