Do you collect rain water at your home or business? If so, you may be helping to reduce flooding, erosion and water pollution problems. The Stormwater Management Discount acknowledges your efforts and reduces your drainage charge.

What’s Eligible for a Discount?

  • Rainwater harvesting systems
  • Rain gardens
  • Green roofs
  • Stormwater ponds

Note – To be eligible, these stormwater control measures must be voluntary, i.e, not required for development.

Amount of Discount

The discount is calculated individually for each address, based on the amount and percent of impervious cover, including driveways, rooftops, parking lots, etc. Each gallon of stormwater storage offsets both your total amount and percent of impervious cover. You may offset up to 50 percent of your impervious cover with this discount. Discounts are calculated the same way for both commercial and residential properties. Here are some examples of potential discounts:

  • 55 gallon tank,  $0.20 to $0.30 per month
  • Small rain garden (60 sq. ft., 6 inches deep), $0.70 to $1.20 per month
  • 1,000 gallon tank, $2.90 to $4.90 per month

Please note that the low end of the range is based on a property with 2,000 square feet and 30% impervious cover. The high end is based on a property with 5,000 square feet and 50% impervious cover.

Find out all the details in the Stormwater Management Discount Guidance Document.

Ready to Apply?

Please note that the City will review the amount of impervious cover recorded on your property and will correct any errors before processing the application. This means your drainage charge could increase or decrease before any potential discount is applied to your account. Use the "Find My Drainage Charge" tool to check your impervious cover before applying.

If your rainwater harvesting system consists of tanks that are each less than 250 gallons, you will need the following information to apply:

  • Utility Account number (You can find this on your City of Austin utilities invoice.)
  • Capacity of your tanks
  • Photo

For systems with larger tanks and for other stormwater control measures, you will need additional documents and information listed in the application, including impervious cover information and a site map. You can use the “Find My Drainage Charge” tool to get impervious cover data and to create a site map. This tutorial will explain how.

Documents and Online Resources