I got to the water and scanned the far bank. There were loads of golden plover, mallards, black-headed gulls, etc. but no yellowlegs. I did come across a wader with very yellow legs and my heart jumped, but it was only a ruff!
The rain was driving into the end of my scope, obscuring my vision, so I walked upwind so I could look with the wind more behind me. Then, there it was on a small island in the middle of the flood. I moved nearer and it flew to a marshy area nearby. I gave it a wide berth and moved beyond it, waiting for it to come nearer to me. It was still raining but I knelt down on the wet grass to lower my profile.
I followed the bird for about 15 minutes but I didn't want my camera to get too wet. I headed back to the car.