Onsite Water Reuse Systems

For the most recent updates from City Council check out the GoPurple page.

Purpose

Onsite Water Reuse Systems which collect rainwater, condensate water, stormwater, graywater, or foundation drain water for non-potable applications such as irrigation, toilet flushing, and cooling applications are regulated under Chapter 15-13 of City Code. These types of reuse systems require a permit from Austin Water to ensure they are designed and operated in a manner that makes efficient and safe use of the water.

Which Projects are Required to Install an Onsite Water Reuse System?

Effective April 1, 2024 Onsite Water Reuse Systems are required for new commercial, multi-family, and mixed use development projects with 250,000 square feet of gross floor area or more. Some projects are exempt from this requirement. Refer to the Onsite Water Reuse Program Guidebook for more info.

Onsite Water Reuse Systems are also required for commercial, multi-family, and mixed use development projects with new or replaced evaporative cooling towers.

The table below summarizes the alternative water sources that must be collected, and the non-potable end uses that must be provided for development projects required to install and operate an Onsite Water Reuse System per City Code Chapter 15-13.

Project Size	Other Project Characteristics	Required Sources	Required Uses
250,000 sf or greater GFA	Project has one or more commercial, multi-family, or mixed use buildings	Combined AC condensate and Rainwater	Irrigation Toilet/urinal Cooling tower
250,000 sf or greater GFA	Project has four or more multifamily buildings with a FAR <1	Combined AC condensate and Rainwater	Irrigation
Less than 250,000 sf of GFA	Project has a cooling tower of 100 tons or greater capacity	AC condensate	Cooling tower

Project Size

Other Project Characteristics

Required Sources

Required Uses

250,000 sf or greater GFA

Project has one or more commercial, multi-family, or mixed use buildings

Combined AC condensate and
Rainwater

Irrigation

Toilet/urinal
Cooling tower

250,000 sf or greater GFA

Project has four or more multifamily buildings with a FAR <1

Combined AC condensate and
Rainwater

Irrigation

Less than 250,000 sf of GFA

Project has a cooling tower of 100 tons or greater capacity

AC condensate

Cooling tower

GFA= Gross Floor Area FAR= Floor to Area Ratio

Step by Step Permitting Process

Refer to the Onsite Water Reuse Program Guidebook for more info.

Site Plan Approval

Step 1. Complete a Water Balance Calculator, Meter Demand Sheet, and OWRS Site Plan Sheet for Austin Water-Onsite Water Reuse (AW-OWR) Site Plan Approval.

Step 2. Submit an OWRS Implementation Plan to AW-OWR and/or Obtain an Encroachment Agreement from Land Management (applicable only to district-scale systems and projects with components in the public right-of-way).

OWRS Application Approval

Step 3. Submit an OWRS Permit Application and Engineering Report to AW-OWR– Go to the AB+C Portal to submit OWRS Permit Application.

Building Permit Approval

Step 4. Submit an Alternate Water System Permit Application to Austin Water-Special Services Division (AW-SSD). This application must be approved prior to Construction inspection.

Step 5. Obtain Building Permits from Development Services Department Commercial Plan Review or Expedited Building Permit Review (DSD-CPR or DSD-EBPR). OWRS Permit Application must be approved prior to Building Plan approval.

Construction Inspections

Step 6. Conduct Building Construction Inspections with Development Services Department Building Inspections Division (DSD-BID)

Step 7. Conduct Cross-Connection Control Test for AW-SSD and Final OWRS Inspection with AW-OWR

Step 8. Submit Documentation for a Permit to Operate from AW-OWR

Operation and Ongoing Monitoring

Step 9. Operate in Conditional Start Up Mode

Step 10. Operate in Final Use Mode with AW-OWR Approval

Project Submittal Resources

Water Balance Calculator (version date 05/15/25)
Meter Demand Sheet (version date 02/04/25)
OWRS Implementation Plan
OWRS Permit Application
OWRS Engineering Report
Application for Fee in Lieu of OWRS
AB+C Portal to submit OWRS Permit Application

Resources

Technical Resources

General Resources

OWRS Case Studies

Additional Resources

National Blue Ribbon Commission for Onsite Non-potable Water Systems

View our webinars to learn key updates and technical guidance on implementing onsite water reuse systems in the City of Austin.

February 28, 2024: Permitting Onsite Water Reuse Systems
March 27, 2024: GoPurple Program Regulations and Affordability Strategies

Dual Plumbing Cost Study

Dual Plumbing Cost Study (in 24 parts)

Incentives for Onsite Water Reuse

To help facilitate the implementation of Onsite Water Reuse Systems, Austin Water offers several incentives as part of its GoPurple program. To learn more about the eligibility and terms of each incentive offered, please download the relevant application or file.

OWRS Pilot Incentive Program Application – AW pays up to $500,000 per qualifying project
Expedited Building Plan Review Rebate Application – AW pays up to $36,000 per qualifying project
PACE Financing Study – AW assists applicants with documenting eligible water savings and project costs

Contact and Program Information