clean water for each dog

So I do farmer's markets and since it's getting hot I wanted to have some water for the dogs that come to the market. 

The traditional dog bowl can get very messy. Multiple dogs can drool on the water, make a mess, etc, and it can get messy pretty easily.

This one is automatic with the sensor and fills the top bowl to the line and automatically stops when the top is full. We have asphalt all over the market, so depending on the dog (like pugs who have flat faces) have dirt and rocks all over their faces from when they are sniffing things and then put their face in the water to drink. After they're done drinking, they leave a pile of rocks and sediments on the bottom of the water. So after the pug leaves, I remove the lid and pump water again. It's so much cleaner for the next dog. 
When market is done and I still have lots of water left inside, I just quickly rinse the top and then rinse my hands with the remaining water that is clean and untouched by dogs. I love it.

I think for indoor use, it would be even better because you only have to clean the top portion. I gave 4 stars because it is a little pricey. 

Charging it is very simple, it's a USB port so just plug it into any port for chargin. I loved it.