Emp exited water truck end of shift stepping onto uneven pavement rolling ankle. Injury treated with RICE. Emp wanted wait see if would be ok but swelling worsened, Supervisor took emp to clinic 03/08/19. Emp prescribed Tylenol, Diclofenac sodium, air boot for up to 6 hrs per day and physical therapy. PT noted boot was not effective after day 3 recommending boot is not required.