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Water Loss Audit

Leak Detection | Water Loss Audit Resources | FAQs

Water Loss Audit Form (New Users)

Water Loss Audit Form (Registered Users)

To access the Water Loss Audit Worksheet online you must first register by creating a username and password.  The New User link will direct you to that page.  Once you have created a username and password, you may use the Registered User link to request access to a particular utility.  Once access is approved by TWDB staff you will receive a confirmation by email granting access.

Please Note: This logon information is different to that established for the online financial assistance application. If you have not previously accessed either the Water Loss Audit or the Water Use Survey, you will need to request access here. If you have previously accessed either one, you may use the Registered User link to request access to your Water Use Survey or Water Loss Audit.

Water Audit Worksheet Resources

For further information or questions, please contact conservation staff. If you are interested in receiving a copy of an entity’s water loss audit report please send your request to WLA-Group@twdb.texas.gov with the entity’s name and requested year along with your contact information. Access to the database should be limited to authorized users. Texas Water Development Board is currently in the process of developing a consolidated database for the water use survey, water loss audit, and annual conservation report. Part of that project will include public access to reports.

Presentations available from the August 22, 2013 Water Loss Symposium.

Who needs to submit?
Any retail water supplier that has an active financial obligation with the Texas Water Development Board is required to submit a water loss audit annually. Additionally, retail water suppliers with more than 3,300 connections are now required to submit an audit annually. The annual water loss audits are due on May 1st.

In addition, all retail public water suppliers are required to submit a water loss audit once every five years. The next scheduled audit for this requirement is for the year 2015 and will be due by May 1, 2016.

We encourage all retail public water suppliers to complete an audit annually to assist them in tracking water loss to help better identify issues that may need addressing.

The Methodology
Traditionally, the water utility industry has used percentages to determine water loss, but in order to more efficiently manage your utility you should be able to answer several questions:

  1. Where did we lose the water?
  2. How much water was lost? (Expressed as a volume.)
  3. How much did the loss cost the utility?
  4. Why did we lose the water?

The Texas Water Development Board utilizes a methodology derived from the American Water Works Association (AWWA) and the International Water Association (IWA).  This new standard uses terminology such as authorized consumption, real loss, apparent loss, and non-revenue water.

  • Authorized Consumption is water the utility gave someone permission or authorization to use, whether it was billed or not.
  • Real Loss is water lost through distribution system leakage and excessive pressure.
  • Apparent Loss is water that was not read accurately by a meter; either as unauthorized consumption, including theft, or data analysis errors. 
  • Non-revenue water is water that the utility does not receive compensation for and may consist of the unbilled categories of authorized consumption, apparent loss, and real loss.

The Water Audit Worksheet is a "top down" audit and is referred to as a "desktop" exercise using existing estimations and records.  If the utility desires to become more efficient, the next step in this process is the "bottom up" audit, which involves a detailed investigation into actual policies and practices of the utility.  It should be phased in only after the utility staff has a thorough understanding of a "top down" audit and the IWA methodology, terms, and procedures.

For further explanation of this methodology and for detail definitions please review the Water Loss Manual.