Store water in soil—inexpensive supplemental irrigation storage in soil (not advisable in landslide areas).
Store water in aquifers—free bulk storage safe from evaporative loss, but only accessible by pump and subject to contamination and extraction by other users.
Store water in ponds—inexpensive bulk storage of water, most appropriate where rainfall exceeds evaporation and the majority of water need is for non-potable uses.
Store water in tanks—most expensive but most flexibility in location and best protection and control of the stored water.
Water Tanks 101
Tanks are the most common way to store water. A well-designed tank offers nearly complete control of storage conditions, including:
security against leakage
protection from mosquitoes and vermin
shade so algae will not grow
minimal or no evaporation
valve-controlled inlets and outlets
Water tanks come in all different shapes, sizes, and materials. Most tanks will have:
an overflow mechanism
provision for sunscreen
Water tanks also can have a host of optional features.
Before installing your water tank you will need to decide where to put it, whether it will be above or below ground, how big it will be, and what material it will be made of. You may also need to meet regulatory requirements.
Situating Water Tanks
The location of your water tank will largely determine:
which parts of your land can be supplied with tank water by gravity
the amount of pressure at every point in the system
the length and cost of pipe runs, control wire runs, and line-of-sight for radio links
how visually obtrusive your tank will be
the vulnerability of the tank and pipes to hazards such as falling trees, rocks, and landslides
the size of tank it is feasible to build
ease of construction and service access
To situate a water tank, you need to consider: