About 80% of the Mountain Beaver range in B.C. is within provincial forest lands. Gyug (2000) documented Mountain Beaver densities 85?95% lower on clearcut sites where heavy machinery had compacted and disturbed soils. The primary effect is soil compaction of sites by heavy machinery that kills Mountain Beavers within their dens and creates long-term loss of dens because the sites are too compacted to be re-excavated when they attempt to recolonize. They may be found in the dense shrub and herbaceous growth that may follow clearcutting, however these populations may be limited by the effect of heavy machinery compaction on soils or become a sink (Environment Canada 2015o). Urbanization and road building within the lower Fraser Valley, as well as the potential for opening or reopening of mines within the near future, are also considered threats (Environment Canada 2015o).
In 2016 there was a proposed hydroelectric run-of-the-river dam that was going to affect an area where this species occurred. Individuals were translocated out of the highest priority disturbance area. There were three mortalities among those translocated, however this will not affect the population (Ransome 2016).

When this calculator was completed in 2015, climate warming or drying was ranked as negligible - this may be an increasing threat and should be re-evaluated (COSEWIC 2022b).