Last night's, or the night before's. Just remembered almost a day or two later.
I was at the beach, or at some sort of beach resort. I walked by the seashore, and noticed the whole shore was bordered with shallow pools of water along the shore, deeper than the edge. Behind the pools was the open ocean. In some of the pools there were people fishing, and in other pools there was nothing happening. In some of the pools there were fish, and they were having races, from one side of the pool to the other. They were having fun. In the open ocean part there were some people swimming.
I approached a building that seemed prominent (like a lifeguard shack, etc.) and talked to someone (male) who told me that before, when people were fishing, no one used to be allowed in the water, and vice-versa, but since "Jim" had taken control of the place, he had organized it so everyone could go in when they wanted, provided they used the correct areas.
It was approaching dusk and I wanted to go in the water, so I dipped a foot in one of the pools, and found the water to be warm, which surprised me, considering the time of the year (it's autumn here in the northern hemisphere). As usual, I woke up before jumping in.