Landscape irrigation is the most common use for rainwater collected in the state of Texas. Harris County uses 2.58 mgal/day for irrigation. [20] Rainwater harvesting provides a sustainable source of water that can help lessen or supplement the use of municipal water. Rainwater is also beneficial for plant and promotes healthy growth. It is free of salts and minerals, often found in municipal sources of water that harm root growth.
It is estimated that the regular water use for residential irrigation is between 30 and 50 percent of total water use. [48] In more water demanding times like the summer, water for irrigation can reach up to 60 to 70 percent of total usage. Rainwater harvesting then can serve as a valuable alternative source of water.