Tue, Aug 16, 2022: 10:30 AM-10:45 AM
516D
Background/Question/MethodsThe Klamath Basin is a highly manipulated watershed, which experienced rapid development of irrigation infrastructure throughout the 20th century. The installation of dams, and draining and ditching of wetlands to support agriculture has resulted in a decline in native fish populations. Of particular concern is the decline in federally-listed bull trout (Salvelinus confluentus), as they have been nearly extirpated from the basin. The extensive ditch and canal network has cutoff critical migration pathways and resulted in a loss of the adfluvial life-history. This has contributed to the isolation of the few remaining populations, resulting in population bottlenecks and low genetic variability. The result is a heightened risk of local extinction of this species. Increasing the suitability of habitat along key migration corridors has been suggested as a way to support the return of an adfluvial life history and increase gene-flow between these populations. A willing landowner presented an opportunity to restore in-stream water rights and decommission a two-mile-long irrigation canal, returning Crane Creek (a key migration route to Agency Lake) to its historical alignment while creating habitat suitable for bull trout migration.
Results/ConclusionsA wholistic restoration approach resulted in the creation of two miles of new stream channel in the historical Crane Creek alignment. The newly constructed stream channel provides egress for bull trout migrating from Threemile Creek to Agency Lake, and also provides access to additional spawning and rearing habitat in neighboring drainages. The channel was designed to raise the water-table and establish a more natural hydrologic regime. The existing canal was graded and partially filled to meet the habitat needs of Oregon spotted frogs, another species of concern within the basin. A collaboration between local landowners, agency staff and non-profit groups resulted in a restored stream corridor which provides key watershed connections to a vulnerable fish population. The restored watershed also provides additional ecosystem services including the establishment of a native riparian vegetative community and habitat for native amphibians, while maintaining grazing and other agricultural activities on the property.
Results/ConclusionsA wholistic restoration approach resulted in the creation of two miles of new stream channel in the historical Crane Creek alignment. The newly constructed stream channel provides egress for bull trout migrating from Threemile Creek to Agency Lake, and also provides access to additional spawning and rearing habitat in neighboring drainages. The channel was designed to raise the water-table and establish a more natural hydrologic regime. The existing canal was graded and partially filled to meet the habitat needs of Oregon spotted frogs, another species of concern within the basin. A collaboration between local landowners, agency staff and non-profit groups resulted in a restored stream corridor which provides key watershed connections to a vulnerable fish population. The restored watershed also provides additional ecosystem services including the establishment of a native riparian vegetative community and habitat for native amphibians, while maintaining grazing and other agricultural activities on the property.