Implementation of Riparian Revegetation & Irrigation at 2 Channel Rehabilitation Sites on Hoopa Reservation 2016

The Hoopa Valley Tribe worked to establish a healthy riparian corridor at two stream rehabilitation sites on Supply Creek and Mill Creek. In expanding the floodplain and areas accessible to the streams the banks were denuded of vegetation. Thousands of plants including willows, cottonwoods, sedges, redbud, and conifers were planted along these surfaces to get a jump on natural recruitment. These tributaries to the Trinity River support Chinook and Coho salmon as well as steelhead trout. This project involved watering the newly planted riparian vegetation at these sites to help them get established so they can improve the ecological function of the channel corridor, supporting cool water temperatures, terrestrial nutrient inputs, and eventually large woody debris. Crews used portable pumps and pulled water directly from the stream. Pumps were fitted with screens to avoid entrapping juvenile fishes. Pumps were attached to a PVC irrigation infrastructure 2 to 3 times per week to water the site throughout the summer months.

We were successful in accomplishing the goal of the project - to provide riparian revegetation for restoration projects to improve anadromous fish habitat on streams located on the Hoopa Valley Indian Reservation and implement priority actions outlined in the Southern Oregon Northern California Coho Salmon Recovery Plan.

Restoration activities, including the riparian planting/irrigating elements implemented in this project at Mill and Supply Creeks will initiate recovery from stream channelization and levee confinement that occurred after the 1964 flood. The project prioritizes habitat improvement restoration actions as described in the Southern Oregon Northern California Coho Salmon Recovery Plan. The project’s goals, objectives, activities and methods are outlined below. Coho salmon rearing habitat is limited within the Trinity River watershed so actions that enhance habitat are critical for species recovery. Mill and Supply Creeks are also used by other species vital to the Hoopa’s tribal trust fishery (Chinook salmon, lamprey, and steelhead trout). Adult (spawning survey) and juvenile outmigrant data exist as a result of long-term monitoring projects funded by PCSRF since 2000.

In the big picture, restoration of Supply Creek and Mill Creek is proceeding through several phases: 1) development of civil designs, 2) construction of designs, 3) planting of floodplain and riparian areas within newly-constructed sites, and 3) irrigation of plantings as needed for a period of up to three years. When complete, the restoration projects will result in immediate short-term habitat creation and support long-term natural physical and biological stream processes. Through a combination of actions including all four enumerated steps, the quality and quantity of salmonid habitat in Mill and Supply Creeks will increase, helping to increase the populations of coho salmon and other salmonids in the Trinity Basin. From a watershed-wide perspective, restoration of the valley floor reach of these tributaries is an opportunity to restore substantial low-gradient winter rearing habitat for both natal and non-natal salmonids in the Trinity Basin.