New Old Idea
Rainwater harvesting is an old idea whose time has come again.
Cisterns have been used for centuries and the technology is well-developed. We in the Southeast have not taken advantage of these systems as much as our neighbors to the west for multiple reasons. Cheap and plentiful water, not to mention our fairly high average rainfall, are the main reasons. Water is still pretty cheap considering it is necessary to sustain life, but the cost has gone up dramatically over the past several years. A large percentage of potable water is used for landscape purposes and this must come to an end if population continues to increase in the Southeast. The "water wars" between Alabama, Georgia and Florida are nothing compared to what the West has experienced for decades. I have heard many futurists say "water is the new oil" in reference to future scarcity concerns on a global level. On the plus side, we have tremendous water resources in the Southeast. On the negative side, we tend to waste things we see as plentiful.
Cisterns or water tanks offer a great opportunity to capture rainwater during the rainy periods for later use in the landscape or to flush commodes – provided your municipality allows this. Farmers are looking toward this resource as well. Capturing rainwater off barns for cattle or poultry houses may soon become a viable option.
Cisterns can vary tremendously in cost depending on size and desired appearance. If you want to try rainwater harvesting "on the cheap," I would suggest you start with a simple rain barrel attached to your gutter downspout. A 55-gallon drum can be attached in a couple hours with a few simple tools at a cost of $50-$100 depending on how much of a "do-it-yourselfer" you are.
Large systems for livestock or commercial agriculture will require large above or below ground storage capacity. The upfront cost may be prohibitive today, but cost-share programs may be on the horizon; so keep in contact with the local NRCS office just in case this becomes an approved EQIP practice like it has out West. For cattle farms with storage buildings in or near pastures, it may provide a very inexpensive way to get water to remote sites even if you fund the entire project yourself.
For homeowners, a rain barrel will not provide enough water to maintain a thirsty lawn or a large garden, but it would provide an inexpensive drink for a container garden or a small vegetable or flower garden. I use a couple of recycled terracotta olive barrels on my front porch to water my potted plants and I almost never hook the hose up to the "city water."
Water is so precious in the western parts of our country that commercial landscapers are required to design a water-harvest system for landscape water needs. These larger systems can be fairly expensive, but can be designed to provide all of your irrigation needs and some of your non-potable water needs in the home. These systems may consist of large plastic, concrete or metal tanks that can be either above or below ground. You can even purchase large water bags that are flat when empty and expand as they fill. These bags can be stored under a porch, in a basement or even in the crawl space of a home.
If you are interested in small scale rainwater harvesting, contact your county Extension office. They have lots of resources available and likely will have a workshop you can attend nearby. If you are interested in large scale systems, your Extension office can direct you to the most current research-based information available. Also, I highly recommend a Texas A&M publication called, "Rainwater Harvesting: System Planning." You may find Extension resources on this topic on their web: www.aces.edu/urban/RainwaterCollection/WaterUse.php.
Tony A. Glover is a County Extension Coordinator in Cullman County.