Our "cold water" tank sits on the roof of our three-story villa, so the cold water is actually very warm. In summer, we turn off the water heater and use the "cold water" tank for our hot water.
The "hot water" tank is elsewhere, out of the sun. It becomes our cold water.
You have to be careful doing laundry in Abu Dhabi in summer. Things have a tendency to shrink; clothes can lose their color. I use the "cold/cold" water setting on the washing machine, and still the water is very warm. I fill the machine and let the water sit as long as I can, so it can cool, before adding the clothes.
We've made friends with a family that is new to Abu Dhabi. We invited them over to swim in our compound's pool. What fun we had - our six children and their four children got along great. We all laughed because the pool water was so hot you had to get out to cool off. It was about 110 degrees that day.
The Arabian Gulf, too, is as warm as bath water at this time of year.