swimmable

From swim + -able.

swimmable (comparative more swimmable, superlative most swimmable)

1. (of a body of water) Able to be swum in or across
   • 2007 January 30, Anahad O’Connor, “Looking to the Hudson for Rockland’s Water Needs”, in New York Times‎^[1]:

     Those efforts have helped the Hudson inch closer to the healthy, swimmable river that it was before industry sprouted along its banks.