Alternate Water Sources
Preventing cross-connections between alternate water systems, also known as auxiliary or alternative water systems, and potable drinking water systems is essential to protect public health. State, federal and City regulations apply to all sites with alternate water systems to ensure the two are never interconnected without appropriate backflow protection.
Alternate water is any water other than Austin Water's potable drinking water, including but not limited to:
- Lake or river water
- Well water
- Reclaimed water
- Onsite water reuse systems — including rainwater, stormwater, condensate water, graywater and other non-sewage water sources
Cross-connection prevention for alternate water systems has three main elements:
- Ensure that new alternate water systems are not connected to the potable drinking water system without appropriate backflow protection.
- On all sites with alternate water systems, ensure that the public drinking water distribution system is protected by an approved containment backflow protection assembly located immediately downstream of all City water meters and City service lines to private fire lines.
- Perform periodic Cross Connection Tests (CCTs) to verify that the private potable drinking water system and the alternate water systems are not connected without appropriate backflow protection.
See the Alternate Water Requirements (PDF) for details.
Recurring Inspections
After an alternate water system is reviewed, inspected and approved, recurring inspections and CCTs are required as follows:
- Inspections and CCTs for black-water sourced alternate water systems must occur annually.
- Inspections and CCTs at multi-family, industrial, institutional or commercial sites must occur once every four years.
- For residential sites, no recurring testing is required after the initial test.
- CCTs and inspections are required whenever the potable water system or alternate water system is substantially altered, or when required by the authority having jurisdiction. The authority having jurisdiction may authorize alternate testing requirements and procedures.
Inspection and CCT procedures are based on the adopted City of Austin Plumbing Code. Tests and inspections must be performed by licensed testers registered with Austin Water's Utility Compliance Services Division. For a list of Water Supply Protection Specialists and Customer Service Inspectors authorized to perform tests, see the Active Water Service Technicians List.
For information on becoming a Water Supply Protection Specialist or Customer Service Inspector, see the Customer Service Inspector Eligibility Requirements page.
Plan Review Process
Austin Water requires a Site Certificate of Occupancy (CO) for customers using an alternate water source. This certifies compliance with Water Protection Program requirements for protecting the drinking water system and for setting and retaining potable and/or reclaimed water service meters. This overview covers CO requirements but does not cover all City of Austin requirements.
Most requirements for installing and using alternate water can be found in Chapter 16 of the latest adopted Plumbing Code, as amended, and Chapters 290 and 210 of the Texas Administrative Code.
- Permitting and Inspection
Austin Water must permit and inspect private plumbing — including potable water, wastewater and drain waste and vent — as well as private alternate water piping, including the alternate water source system and its uses such as irrigation, cooling towers, toilet and urinal flushing. The applicant must receive and sign the inspection document and the Developer's/Contractor's Check List when the application is submitted.
- Drawings and Specifications
Austin Water requires the following drawings and specifications to apply for a CO or water meter installation:
- Drawings submitted with the application
- All private piping inspections (plumbing, irrigation or process)
Regardless of requirements from other entities, deliver this set of drawings, specifications and written processes to:
Austin Water, Utility Compliance Services Division
3907 South Industrial Drive, Suite 100 Austin, TX 78744-1070- Required Meetings
There will be an initial meeting with the Utility Compliance Services Division to review the process and requirements, and a final meeting to:
- Formalize the roles of the water customer and Austin Water in safely operating the facility and responding to accidents or emergencies
- Provide the name, title and contact information of the alternate water system operator on the premises
- Provide the name, title and contact information of the Austin Water contact for accidents, emergencies and routine matters
- Site Testing and Inspection
In addition to inspecting and testing plumbing and process piping to confirm approved materials and methods, sites with alternate water use require inspections and tests to prevent and identify cross-connections between potable water piping and any other on-site piping system — particularly those containing hazardous materials.
Inspections and tests must be performed after all piping on site is installed, pressure tested and accepted by the plumbing inspections department. Potable water must never be used to fill or test an alternate piping system without proper use of an RPZ backflow preventer, even during construction. Alternate water systems are not built using the same processes as sanitary piping systems — their interconnection for filling could contaminate the potable water system.
All inspections and tests must be performed before any connection is made to any alternate water source. This means the reclaimed water meter may not be set, and well, rainwater or other pumps may not be started, until testing is complete.
- Cross Connection Testing
Austin Water alternate water customers must use a qualified inspector to perform initial inspections. The inspector will look for proper safeguards to minimize the risk of exposure and cross-connections, and will pressurize and vent the various piping systems to confirm whether the potable and alternate water systems are connected or separate. The initial test uses a protected source of potable water before the alternate source is activated. Subsequent tests use the alternate water system supply.
- Final Checklist and Activation
When the CCT is complete, the inspector will certify the results using the CCT Form and deliver the certificate to the Utility Compliance Services Division at the address listed above. This completes the checklist to set the reclaimed water meter and/or activate other alternate water systems and receive approval for the CO.
Note: Austin Water's approval to issue a CO does not release holds or requirements placed by other agencies or organizations.