Every Last Drop
Since we actually received an entire inch of rain today for the first time in over one year, I find it even more critical to emphasize the importance of harvesting rainwater…particularly here in the southwest United States. Every drop counts for those of us living in arid climates. Some water wells of small towns and individual homes are already pumping air in this area of West Texas. If you live in a place where there is not a significant underground aquifer, you are vulnerable to this occurring, as well.
Growing up on a dryland cotton farm where the desert gave birth to the prairie, rain has always been a focal point in my life. Our average rainfall of 17 inches a year leaves a person constantly looking skyward in search of a dark cloud – begging, pleading, praying, asking for relief in the form of moisture. Often we go three months with less than one inch of rain. We’re a parched people on these High Plains. In early spring months, sand pours through the sky like a colossal ancient glass measuring the limitations of our mortality rather than time.
It gets so dry out here that even when it rains, the drops are wet on just one side. Summer crops often sizzle like a month-long campfire breakfast. Nothing but hot wind moans, fueling their smoky inferno of an existence. Grown men cuss the drought and heat. Women long for a mountain getaway beside a man hankerin’ for a kinder climate. Jackrabbits grab their fur, hunker down, and sob silently in the shade as they dream of winter.
All the old creeks and streams that once trickled through West Texas are nothing more than veins bled dry by a century worth of sweat, wind, and grit. We’re blessed with one of the largest underground aquifers in the world – the Ogallala Aquifer. But with more than half a century of widespread irrigation (30 percent of the U.S.), volatile oil drilling, and other abusive methods, we’re not sure how much longer it will be plentiful for all of us.
Most water here in West Texas is less than pleasant to drink. We’re infamous for our water’s harsh taste. It’s hard on pipes, appliances, and the colon. Since moving back to the farm seven years ago and purchasing my great-grandparents’ original homestead, I’ve focused intensively on rainwater harvesting. There’s been some hard lessons learned, giving me valuable experience in this vital practice.
For every square foot of roof space, expect to catch about 0.62 gallons for every inch of rainfall. So, a 1,000 square foot house will harvest about 620 gallons from one inch of rain. Metal roofs and gutters are ideal, but one can also catch rainwater from shingled or clay tile roofs efficiently as well. Shingled roofs pose a small issue as granular debris from the shingles will constantly be in the water, but a simple filter can remove those tiny particles. Having a vertical runoff catchment system, made of schedule 40 PVC, on your gutter system also helps eliminate this. The catchment also helps catch dirt, leaves, bird poop, or other materials your gutter screens (and you definitely want gutter screens) do not keep out. Running three-inch or four-inch PVC from the gutters into tanks keeps everything strong, clean, and efficient. Gravity is the only friend you need in getting rain from the roof to your tank. Allow an 18-inch difference from the roof to the tank top.
I’ve harvested rainwater with trash cans and five gallon buckets but soon graduated to black (or dark green) poly tanks ranging from 300-3,000 gallon capacity. Clear or white containers are not recommended as they gather mold. Which is fine if you’re simply watering trees, plants, or a garden, but the mold will clog up spigots and hoses. You can get creative and paint them a dark color if that’s what you have to work with or simply cover them with a small tarp. Poly tanks are also not recommended for human drinking consumption. When using an enclosed tank, make sure you give the water somewhere to go once the tank is full. Most poly tanks come with a spill hole at the top. A tank can explode when pressurized internally with more water than it can hold.
Pioneer Water Tanks (an Australia company) make the finest rainwater harvesting tanks out there for human drinking water and household use. A company in Austin, Texas called BlueScope is a dealer. You can find a local dealer across much of the country. Their tanks have a special liner specifically for human drinking. They’ll install the tank on your property. It’s not cheap, but it’s cheaper than drilling a well. Tanks range from 1,000 gallons to 50,000 gallons. I like to allow for 10 inches of rain storage. If you live in a wet climate, you might want to double that.
We have a 10,000 gallon tank for our garden and orchard, as well as a 40,000 gallon for our barn. I’m currently ordering another tank to run our entire household (showers, sinks, etc.) on rainwater. My horse drinks half the amount of rainwater as he does well water. This tells me he’s getting his thirst nourished with much less water. Rainwater is also a neutral pH, which is better for plants and the human body. Most water here is extremely alkaline. My garden thrives with rainwater.
If you’re on a tight budget, it’s not necessary to spend thousands of dollars. Use whatever containers you can to help water small gardens, trees, and other vegetation. I try to plant drought-tolerant vegetation, but I only have so many needs for cactus.
Digging large wells (18-inches from tree base and six-eight inches deep) around trees allow anywhere from 30-50 gallons of water to sink into its roots on a good rain, rather than running off onto grass, dirt, or roads. By not building a high border around the outer rim, this allows more rain to enter the bowl or sink zone for the tree’s roots. Other ideas promoted by permaculture techniques such as building swales allow you to harness the landscape’s utmost potential for rainwater. For those of you who live in wet climates, know that I envy you…so do not discount consistent rainfall. Good rains here are literally manna from heaven for us farmers.
Remaining focused on our weather patterns, I often find myself talking to the clouds, hoping they bless our land, our crops, and even our thirst. With substantial rainwater tanks in place, I take great pride in the fact I’m not letting a single drop go to waste. But I still keep one eye on the sky and an open invitation to any and all rain clouds except when harvesting crops…but it’s hard to turn down a good rain out here, so we just take it when we can get it.