Bank swallows (Riparia riparia) are a colonial species of swallow that build their nests by burrowing into eroding banks associated with streams, rivers, coastal bluffs, and lakeshores. Their populations have declined worldwide primarily due to bank stabilization activities. Declines observed on the Sacramento River in the late 1970s and 80s prompted the California Fish and Game Commission to list bank swallows as state-threatened in 1989. The Sacramento River accounts for 70% of California's bank swallow population and contains critical habitat for the species. We used monitoring data from 1986 - 2021 to analyze population trends and estimate the extinction probability for bank swallows on the Sacramento River between Red Bluff and Colusa, CA. Burrow counts declined by 9% per year from 1986 - 1995, with the number of colonies following a similar trend. Burrow counts and the number of colonies did not decline between 1996 and 2021. During this time frame, the population exhibited density-dependent population growth. Using a count-based population viability analysis, we estimated a 0.0002 probability that this population will fall below 4,000 burrows in 50 years. Conservation efforts since the 1989 listing appear to have been successful in preventing further declines on the Sacramento River.