The fishing pool has had a minor update to v0.12.1b.
[SLC] Gatherables :: Fishing Pool
In this update, we’ve made the item phantom so that if you have boats travelling across the water, or you have people swimming, they will allow you to pass through. This does not affect their ability to be clicked for gathering.
This is not a forced update. You don’t have to update, but if you feel having phantom is important to you right now, simply re-rez the item to get an update notice.