This webpage serves as a resource for Austin Water customers who are considering collecting rainwater, graywater, stormwater, condensate water or other non-sewage originated waters on their property (onsite), and reusing them for non-potable applications.

Onsite water reuse systems, sometimes referred to as water recycling systems, when properly designed and operated, make efficient and safe use of water that would otherwise be diverted to a treatment plant or water body. Onsite water reuse also provides a property owner with a supplemental, local water supply that can have economic and environmental benefits. For example, collecting and reusing water onsite reduces consumption of the City’s potable water supply, and at the same time saves energy since the water will only need to be treated for its intended use. 

See the schematic below for a description of alternative onsite water sources and graywater that are allowed to be reused onsite.

Graphic of Alternative Water Sources

Guides for Customers

In the City of Austin, the permitting requirements for onsite water reuse systems vary by the water source (rainwater, graywater, etc.), by the intended use of the water (irrigation, toilet flushing, etc.) and by the type of development where the water will be collected and reused (single family, multi-family, and commercial). Building Code separates development into three categories:

  • Single family residential- includes detached one- and two-family dwellings and multiple single-family dwellings (townhouses) not more than three stories above grade plane in height with a separate means of egress and their accessory structures
  • Multi-family residential– includes apartment buildings, or any other residential structure that doesn’t meet the definition of a single family dwelling
  • Commercial – includes all non-residential structures and their accessory structures

To obtain a guidance document for onsite water reuse systems, click on your development type above.


Special Guidance for Onsite Reuse of Blackwater

Blackwater, also known as domestic wastewater, includes toilet waste and other organic waste that requires advanced treatment in order to be reused in a building. The City of Austin is currently piloting a blackwater reuse system at the city’s new Permitting and Development Center to demonstrate how to safely and effectively reuse blackwater in a commercial building. 

Permitting a blackwater reuse system in Austin requires a permit from the Texas Commission on Environmental Quality (TCEQ), and review and approval by multiple City of Austin departments. Austin Water is currently developing a guidance manual for blackwater reuse systems. In the meantime, customers are encouraged to contact Austin Water staff for assistance with permitting onsite blackwater reuse projects.


Regulations for Using Alternative Water and Graywater 

Both state and local regulations apply to onsite water reuse systems in the City of Austin. State allowances and criteria for onsite water reuse systems can be found in 30 TAC Chapter 210 Subchapter F. If used in accordance with this subchapter, no authorization to reuse these waters is required from the Texas Commission on Environmental Quality (TCEQ) unless directed by the executive director of TCEQ.

Local system design, construction, installation and permitting requirements for onsite water reuse systems are found in the City’s Plumbing Code (Chapters 15 & 16 of the Uniform Plumbing Code). The City’s Plumbing Code applies to:

  • any property in the City’s zoning jurisdiction
  • any structure served by the City’s water utility, Austin Water.

The City’s Plumbing Code also stipulates that a graywater system used for outdoor irrigation is not permitted in the Edwards Aquifer Recharge Zone. The following interactive map may help you determine if the City’s Plumbing Code applies to your property, and whether your property lies within the Edwards Aquifer Recharge Zone.


Services We Provide

The permitting of an onsite water reuse system in the City of Austin involves coordination with multiple City departments. As a courtesy to its customers, Austin Water provides help navigating the permitting process for property owners who want to install an onsite water reuse system.

Austin Water – Conservation Division

Phone: 512-974-2199