Hi, could you please have a look at note https://www.openstreetmap.org/note/4312048? Thanks!

In short, judging from out of copyright NLS Maps, this is a place name / a name for this part of the river, not a swimming pool, and I suspect the Maproulette challenge that changed it to swimming_pool may have been mistaken about the assumption that all places tagged water=pool were used for swimming. Do you know that this place is actually used for swimming?