My nephews were staying with us one summer so we decided to make a giant water blob outside for the kids to play on to keep cool. It kept them entertained all day long!
Step 1: Supply List
You can just use a couple old plastic drop cloths used from painting for this project and some duct tape! Originally I was going to add food coloring to the water I put inside but decided against it when I went to fill it up and I'm glad I did.
Step 2: Assembling the Giant Water Bed
I started out by taping the tarps together to make two 40' x 10' tarps. Then, I folded them each in half to make two 20' x 10' double-layer tarps. I doubled the layers because my tarps were pretty thin and I was a little skeptical they wouldn't hold up with three kids running and jumping on them (good call on my part).
Once the 20' x 10' double-layered tarps were on top of each other, I rolled the edges and duct taped them in place. I left a small hole in one corner for the hose. The whole process took about 40 minutes.
Once taped, I stuck the hose inside so there were 2 layers on bottom and 2 layers on top and started to fill it up. I had the kids show me where the initial leaks were and we patched them up (there were only 1 or 2) and filled the whole thing up.
It works best on flat ground. If you start out on a hill, even a little one, one side will be far more full than the other.
I made them wait until it was completely filled to play on it and it lasted for a whole day of play. Eventually little tears would happen but it just helped keep the top slippery, cold and wet and didn't prevent them from using it.
Step 3: Play!
Paired with popsicles and squirt guns, this was the ultimate outdoor day of play. They would run across the yard and slide on it. They would roll and watch the ripples go all the way across. The water kept them cool and it was a big hit with everyone, even the grown ups!