Project Effectiveness Monitoring in the Fender Mill Side Channel

Side channel restoration to improve juvenile salmonid rearing habitat remains a key component of the Upper Columbia Basin salmon recovery habitat enhancement strategy. Side channel restoration projects often focus on diverting main channel surface waters to create inundated off-channel habitat, either as a flow through side channel or backwater alcove. Yakama Nation Fisheries recently completed a promising new type of side channel restoration project which involved using a sophisticated groundwater collection system instead of surface water diversions to create thermally enhance side channel surface flows. Known as the Fender Mill Side Channel Restoration Project, Yakama Nation Fisheries reconnected roughly 2,000 linear feet of side channel to Methow River located between the towns of Winthrop and Mazama using a groundwater infiltration gallery.



The goal of this proposed project is to evaluate benefits and limitations of connecting side channel systems using groundwater infiltration galleries. The project will evaluate how the Fender Mill Side Channel Restoration Project is used by spring chinook, steelhead, coho, and bull trout. It will explore the potential impact of thermally enhanced flow has on growth and survival of juvenile salmonids. Metrics of juvenile growth and survival collected from the Fender Mill side channel will be compared to similar data collected by co-managing agencies monitoring other side channel and main stem habitats in the Methow Basin.



We propose to conduct snorkel surveys at the Fender Mill side channel seasonally in the summer, fall, and late-winter/early-spring. All fish will be enumerated by life-stage and species (using PSCSRF funds). Spawning ground surveys will be conducted annually for steelhead, spring Chinook and, coho salmon (non-PCSRF funds).



Collect up to 1,000 juvenile steelhead, 1,000 juvenile spring chinook, and 1,000 juvenile coho using snorkel herding and/or electrofishing each fall season (using PSCSRF funds). Juvenile steelhead, spring Chinook (using PSCSRF funds), and coho (non-PCSRF funds) will be measured to the nearest mm, marked with a unique PIT tag, and released back into the Fender Mill side channel (FM) after a 24 hour holding period. A PIT tag detection system will be maintained year round in the outlet of the FM channel (non PSCSRF funds). Snorkel herding and/or electrofishing will be used as a recapture technique during the late-winter/early-spring (using PSCSRF funds). Fish will be scanned for PIT tags and fork length measured to the nearest mm to determine overwinter growth (using PSCSRF funds). Individual growth will be measured directly in recaptured, PIT tagged fish and mean size for the FM population will be calculated by species (using PSCSRF funds). Over-winter growth and spring pre-migratory size of juvenile salmonids sampled in the Fender Mill (using PSCSRF funds) will be compared to the pre-migratory size of juveniles salmonids sampled by co-managing agencies in the Silver Side Channel, Methow River flow-through channels, and main channel habitats (non PSCSRF funds).



Tagging to emigration survival rates will be calculated based on the number of fish tagged, detections at the FM channel outlet, and a measure of detection efficiency (using PSCSRF funds). These data will be calculated and presented (using PSCSRF funds), and will be compared to a similar metric from the Silver Side Channel (non PSCSRF funds). A measure of relative survival between fish tagged and overwintering in different habitats will be made by comparing tagging to Rocky Reach Dam survival rates. These measures will be used to compare FM channel (using PSCSRF funds) to other side channels and main channel habitats (non PSCSRF funds).

This proposal seeks to create a monitoring project that will evaluate benefits and limitations of using groundwater to restore side channel habitat. The proposed monitoring project will detail how both target and non-target fish species actually use the restored Fender Mill side channel, and compare the effectiveness of this type of side channel restoration action towards increasing juvenile salmon growth and survival in relation to other side channel reconnections recently completed in the Methow Subbasin. Intensive effectiveness monitoring of side channel reconnection projects is now taking place throughout the region, with a specific focus on the effectiveness of recent side channel restoration actions in the Methow Subbasin. At present, three separate monitoring programs conducted by co-managing agencies are assessing fish use and response to most of the recently completed side channel treatments. However, while these monitoring programs are critical to increasing our scientific knowledge of the effectiveness of differing side channel types and restoration techniques, none of these programs are currently set up to monitor the Fender Mill side channel or the response target species might have to infiltration gallery fed surface waters.