Cripple Creek and its tributaries once drained an extensive watershed north of Chena Ridge. The watershed provided important habitat for many aquatic species including chum and chinook salmon.
In the 1930s, the Chena Pump House was constructed to pump water over Chena Ridge for hydraulic mining efforts near Gold Hill. To expedite the return of hydraulic runoff (water and sediment) to the Chena River, engineers considered two alternatives: Excavate a tunnel almost two miles long beneath Chena Ridge, or construct a drainage ditch almost six miles long around the northern toe of Chena Ridge. In the end, Cripple Creek Drain or “the ditch” was completed in 1935. The lower reaches of Cripple Creek have not seen sustained flow since that time.
While the drain or ditch was an effective solution for the products of placer mining, the abandonment of Cripple Creek resulted in a tremendous loss of wildlife habitat. The lower reaches were effectively channelized down the ditch, which diminished habitat complexity, especially important eddy and pool structures along with important organic debris. Some hardy species, such as grayling, sculpin and blackfish, were able to survive in the drain. However, an important rearing area for chum and chinook salmon was lost.
For many years, this remained the status quo. In 1996, a new intersection at Chena Ridge Road and Chena Pump Road required rerouting lower Chena Ridge Road. The new ditch culvert can been seen in 1996 aerial imagery.
However, no culvert was included to connect the channel of Cripple Creek through Chena Ridge Road. Over time, limited flow accumulated in the channel as impounded water on the north side of Chena Ridge Road. This unanticipated impoundment formed a continuous stagnant pond reaching well above Chena Spur Road to the north.
IALT, in partnership with the USF&WS, commissioned feasibility studies determining requirements for returning flow to the historic Cripple Creek channel. Several options were considered but each was just out of reach logistically and financially. In the fall of 2014, IALT learned that Alaska Department of Transportation and Public Facilities planned to replace the aging ditch culvert at the intersection of Chena Ridge and Chena Pump roads in the near future. The ditch culvert replacement project provides a great opportunity to place an additional new fish passage culvert in the abandoned Cripple Creek channel, restoring some flow to lower Cripple Creek.
Currently, Alaska DOT&PF has scheduled the ditch culvert for replacement during the summer of 2018 (contingent on funding and timing with other project priorities). IALT, working with USF&WS and Alaska DOT&PF hopes to complete both culverts at the same time, restoring continuous flow to Cripple Creek for the first time in more than 80 years. This project, if successful, will be a huge step toward significantly restoring the Cripple Creek watershed, and in the process restoring a great local aquatic resource.
Effects of this stage of the project will be confined to the 93 acre parcel immediately downstream of Chena Ridge Road and entirely owned by IALT.
Additional work to further restore Cripple Creek watershed and aquatic habitat:
- Reconnect Happy Creek to Cripple Creek channel
- Redirect ditch flow back into Cripple Creek near Happy Creek
- Replace Chena Spur Road culverts
- Modify the culvert at Old Chena Ridge Road for fish passage guidelines
IALT is actively working with partners including ADOT&PF, USF&WS, and ADF&G to successfully complete this project. If you can help or if you’d like further information, please don’t hesitate to contact Owen Guthrie (firstname.lastname@example.org).
History of Cripple Creek presentation by Bob Henszey, USF&WS.