In order to move cattle every day, you have to figure out where and how they are going to get their water. Cows drink a lot - some estimates say one cow can suck down (that is in fact how they drink - they suck) up to 30 gallons a day, particularly when it is hot and the calves are still nursing.
The vast majority of cows you see in the US milling around on the hillsides as you drive by are being "backgrounded." They are born on ranches around the country where they nurse and learn how to eat grass. At about 9 months old, these backgrounded calves then are sold into feedlots. The majority of feedlots house less than 1000 cows, but the 5 percent of feedlots that have more than 1000 produce 85 percent of the beef available in stores. Feedlots with more than 32,000 head control 40 percent of the market.
We don't send our cattle to feedlots. Instead we move them every day in a rotational grazing system so that they spend their whole lives (about thirty months) eating only grasses on pasture.
One can only imagine the logistics of watering 30,000 cattle x 30 gallons a day (900,000 gallons every day!). For us, the challenge is to provide enough water without letting the cattle wade around (and shit in) our ponds. To keep the water clean and the cattle well watered while moving them from pasture to pasture every day is one of our biggest challenges.
So we looked around for a mobile watering system. The idea was to pump water out of the ponds (we have many of them) and into big heavy portable waterers using a solar powered pump. But the problem is that we need the pump to turn off not only when the waterer is full, but we also don't want it to burn out turning on and off a million times a day as each cow sucks down her share of water. We need a way for the water to go down to a certain level before it refills, and then to not refill again until the water is emptied to that point again.
We bought a pump to test out and John built a little float for it to sit in, atop the water, while it does its thing. He moves the contraption from one herd to the other (we have two herds currently - 28 cow/calves and 25 yearlings) twice a day. This has added even more time to the already time consuming process of moving cows. Yesterday we received a second pump in the mail and will build it a "floating nest" too.
We have not yet connected it all to the solar panel because we haven't known the correct switch to buy. The on/off mechanism has also been elusive, but just today John received word from a fellow farmer who has a similar set up and can help. While we get it all figured out, the cows are pretty dang pleased with the simple system too.