A rainwater harvesting system consists of the supply (rainfall), the demand (water needed by plants), and a system for collecting water and moving it to the plants. Simple systems distribute rainwater immediately. Complex systems store some or all of the rainwater for later use.

Rainfall. “Run-off” is the rainwater that flows off a surface. If the surface is impermeable (for example, pavement, concrete, roofs), run-off occurs immediately. If the surface is permeable, run-off will not occur until the surface is saturated. Run-off can be harvested (captured) and used immediately to water plants or stored for later use.

Plant Water Requirements. The types and numbers of plants in your landscape, along with their growth stages and sizes, determine the amount of water your plants need to be healthy. Because rainfall varies throughout Texas, different plants have become adapted to conditions in different regions of the state. Plants native to your region are the best choices for your landscape because their water requirements are usually met by normal rainfall amounts.

Water Collection and Distribution System. Rainwater collection and distribution systems can be incorporated into almost any existing site, although it is easier to incorporate them into new construction.

Use the calculator on this Web site to help determine cumulative storage and supplemental water use for your rainwater harvesting system.

Related Resources

Rainwater Harvesting

Homeowners and landowners can construct systems to capture, store and use rainwater to water their landscape plants.

 

Storage and Supplemental Use Calculator

Determine cumulative storage and supplemental water use for your rainwater harvesting system.