A fanastic spot for either a quick dip or a long swim upstream. The Frome is navigable up to the bypass. It is a tidal river so tide times need to be checked as the water levels can drop to less than a metre. If the tide is coming in or slack then it's easy to go upstream, if the tide is coming out then a little harder.
You can swim downstream but getting out points are limited and there is a lot of boat traffic. Upstream is quieter, with mostly canoes/kayaks and small boats due to having to go under the bridge for access.
This is a crowd-sourced map. Abilities vary, and conditions change. Always assess risks for yourself before getting in.