Yes - except when it's high tide AND there's been lots of rain; most of the time it's barely ankle deep and the dogs from La Casona would happily follow me across too.
Honestly though, Pelicano Surf Camp is a much more awesome spot. Very chill vibes, a really nice crowd (half local and half travellers) and literally a few minutes walk from La Casona.
The bus up to San Salvador costs $0.60 and departs every quarter of an hour.