September 3, 2013
Of course you have rainwater. It is God's gift to the earth, its creatures, and its plants. We all live off the rainwater that falls from the sky. In large cities lakes are built to capture rainfall runoff and store it for later treatment and distribution. In rural areas a small portion of rainfall, normally not more than 5%, finds its way into underground aquifers where it is stored and pumped out later for use by homeowners, farmers, ranchers, water supply companies, etc.
With Texas growing population the pumping from our underground aquifers, which have faithfully served Texans for generations, is increasing and aquifers are drying up. People are looking for alternatives since life is dependent on pure, clean water.
The answer is clear and obvious - the rain that falls on your home, which is free for you to capture and use to supply your daily needs. A typical home/garage with 3000 square feet of roof area can capture 1800 gallons of pure rainwater with each 1" of rainfall. Over the year the total rainwater available for capture with our normal central Texas rainfall of 32" per year is more than 55,000 gallons. With more roof area the rainfall captured increases.
Thousands of central Texas residents have opted to use rainwater as their primary source for pure, clean potable water. A typical residential rainwater collection system consists of these basic elements: screened gutters to collect water from the roof; piping to convey rainwater to storage tanks; a large storage tank or tanks to hold the rainwater for future use; a pump and pressure tank to maintain the pressure needed for household use; a filtration and sterilization unit to remove any foreign matter and sterilize the water prior to use in the home.
The secret to a successful rainwater collection system for residential use is having adequate tank capacity to get by the dry months, sometimes three months without measurable rainfall. The minimum amount of tank capacity normally recommended for residential use is 20,000 gallons, approximately 7 feet tall and 22 feet in diameter. For larger families more tank capacity is recommended.
Watering lawn grasses with stored rainwater is not recommended unless tank storage capacity is dramatically increased. Opt for native plants and drought tolerant grasses that are adapted to the central Texas climate.
Rainwater systems for residential use are more reliable than a traditional well pumping groundwater. If the well pump fails, you are out of water until it can be replaced. If the well goes dry (common now), you are out of water period. With a rainwater collection system there is a large tank that is unlikely to go dry, but can be refilled within hours with truck-delivered water to get by until the next rain.
Professionals are available to help you with the design, installation, and minimal maintenance of a residential rainwater collection system. Go to the website of the American Rainwater Catchment Systems Association for information, pictures, and local professionals who are trained in rainwater systems of all types.
For potable water in central Texas the answer is clear, and pure: Rainwater, Rainwater, and Rainwater.