Where I live the cold city water is about 26c in The summer and even in winter it comes out about 22-23c. I live in a house. When you live this far south that's what you get.
I just mix up my developer at whatever temp the water is and adjust the time. I then stop with tap water and fix with fixer that is ambient room temp then finally wash with tap water.
It works for me as I am too lazy to try cool things down and keep them there.