From August 1 to September 30, 2018, a fish weir was operated on the upper Sustut River. This weir has been used for twenty five years to count migrating summer-run Steelhead (Oncorhynchus mykiss) and provides annual monitoring information for this species. Two hundred and ninety-nine (299) Steelhead were counted passing the weir in 2018. This total is 29% of the estimated carrying capacity (1036) and 39% of the average annual count for this project (n=762). These totals may not accurately represent the 2018 population size of upper Sustut River Steelhead. Extreme low water conditions in 2018 appear to have significantly delayed or blocked migration through the weir. Prior to weir removal on October 3rd, 2018, several hundred fish, mostly Steelhead, were observed in two holding pools immediately below the weir site. For management purposes, the population status for 2018 is below the Conservation Concern Threshold and is inside the Conservation Concern Zone. However, due to the aforementioned uncertainty in total population size, this designation should be interpreted with caution.