Rainwater harvesting

What is Rainwater Harvesting?

Rainwater harvesting is the collection and storage of rainwater, offering an effective way to conserve water in your yard.  You can collect rainwater from a roof, which is the most common method, and store it in catchment tanks, such as rain barrels.  Systems for harvesting rainwater can be as simple as placing a barrel beneath a gutter downspout to collect a small amount of water for use on gardens and plants. Rain barrels are simple to install and can be made easily at home.

Reasons for harvesting Rainwater


By collecting rainwater and using it on your lawn, plants, flowers, trees, and shrubs, you can save water and money.  In fact, by collecting rainwater from just 10% of the residential roof area in Texas, we could conserve over 31 billion gallons of water annually.  Using collected rainwater has three major advantages:

  • it reduces runoff pollution,
  • it can reduce your utility bills (the water if FREE!)
  • it is healthier for plants than treated water.

Other Incentives

Texas Tax Code 151.355 exempts rainwater-harvesting equipment from sales tax.  To download the Texas Sales and Use Tax Exemption Certificate, visit www.comptroller.texas.gov/forms/01-339.pdf.

Is Rainwater Harvesting Illegal in Texas?

Rainwater harvesting is good for your wallet and the environment! Efficient use of water is critical in Texas because of its growing population and limited water supply.  Even if you live in an area with minimal rainfall, you can still conserve precious water, save money, and prevent flooding and erosion.

Texas has several laws that support rainwater harvesting.

  • Texas Property Code prevents a homeowner's association from prohibiting the use of rainwater harvesting systems (Texas Property Code 202.007). (This law also promotes composting, efficient irrigation, and drought-resistant landscaping.)
  • Many water-efficient products can be purchased tax-free during a specific weekned (usually around Memorial Day in late May) each year, including rainwater harvesting equipment.  Check the State Comptroller's webpage on this program for future tax holidays.
Cross-Connection Control and Rainwater Harvesting

TCEQ does not recommend the installation of backflow-prevention assemblies at all service connections.  However residences and other buildings or facilities that use an auxiliary water supply, such as a private well, a rainwater harvesting system, or a pump in a lake, must install an RP at the meter connection or provide an air gap at the meter.  If it can be documented is a CSI that the plumbing system of the auxiliary water supply and the plumbing system of the potable water supply are physically separated and not cross-connected then this separation distance may serve as an air gap.