watering system

We have two barns on our property; one is approximately 100 years old and the other is much newer, but neither of them have power or water.  When we decided to start raising animals I knew I had to provide them water, but I was not sure how to go about doing so.  I figured the best way would be to run a water line from the house to the barns... 

In order to get a water line out to the barn, I was going to have to rent a trencher which was going to be quite expensive, plus I had to separately rent a trailer to haul the trencher.  Now for those of you who may be thinking "why not dig it by hand?"  Well, the trench would have to be at least 32" deep to ensure that it would not freeze in the winter and it was going to have to be about 700 feet long.  If I was still in my 20's and not all banged up then maybe I would tackle that by hand, but it was simply not an option for me at this point.  Between the trencher and pipe, I figured I needed to come up with another idea.

I opted to go with a 30 gallon plastic tank that would be mounted to a small trailer and pulled behind the riding mower.  The animals only use about 15 gallons of water each day so this has worked out fairly well for us.  I would like to get a larger tank, fill it up once a week and leave it in the pasture, but the system we have now allows my children to fill up the tank, drive down to the animals, and take care of it all by themselves.

I guess for now we will just stick with the adage of, "if it ain't broke, don't fix it".