This is one of the biggest challenges for free range pig producers.
Where you have water you will have spills and where there is moist earth there are busy snouts. Pigs cannot resist wet dirt and will undermine the best planned watering systems.
If the troughs are too large they will lay in them, if they are too small they will tip them over. Pigs will attempt to get the water on the ground to wallow in it. Solution! well, part of the solution, is to give them a wallow or be prepared to continually lose the battle of upturned, dug out troughs.
The water pipe is not safe either. It needs to be well hidden, buried or inaccessible or the pigs will destroy that too.
Keeping water up to your pigs is a serious matter. They can dehydrate quickly in hot weather. A pigs food intake is also limited if water is not readily available. They just will not eat if they are thirsty.
Water is precious and if you are not connected to town water, you are in serious trouble if your pigs destroy a water line or upturn a trough and run your tank dry.
Water systems either need to be placed on a concrete platform that can withstand the attempts by pigs to undermine it, or be a movable unit so that if holes start to be dug too deep it can be moved to a new location.
The trough pictured to the right is a result of years of battle with pigs and water. It is cement and weighs 100kg making it relocatable yet difficult for the grower pigs to push around. To use this trough for sows however, it would be advisable to drive two star pickets in each side and securely attach the trough with heavy wire. 100kg can be moved by an insistent sow. To overcome the trough being undermined when the soil around it gets wet from spills, it has been placed on a heavy metal grid. This one is actually a piece of pig grating. The pigs will eventually dig out under the grid but it will take them quite some time. The whole setup can then be moved a couple of metres away. Note that the hose fitting has been placed as close as possible to the electric fence and the tap handle has been removed.
This one is called a dog trough and was purchased at a produce store that sells all sorts of cement troughs.