The two types of electrically driven pumps that can be used for an alternate water supply are submersible pumps or suction pumps. Every system will require a voltage regulator to prevent overcharging and a battery saver to guard against draining the battery. Each system is reasonably priced. Final selection should be based on site specifics regarding accessibility to sunlight, water or wind resources. If there is a reliable flow of water, these systems are usually simple to install and easily maintained.
Costs are quite reasonable, but vary widely, depending on site characteristics and system criteria.
Devices are required to collect water from reliable spring, stream or flowing tile, and direct it by gravity to a watering tank, as depicted in Figure 2 . Many of the systems discussed earlier will require a water tank for storage. It is recommended that the tank be sized according to the livestock water requirements indicated in Table 1 . A concrete tank is the best option if dealing with a large number of animals. Tanks should be shaded to control algae growth and enhance water quality, as depicted in Figure 3 .