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Public Drinking Water Source Locations: Checking and Maintaining Accuracy

How to make corrections to locations, how to map new locations, and tips for accurately mapping locations.

The most important component of source water assessment is the physical location of the drinking water source. The TCEQ has had to rely on many outside agencies and individuals to provide locations for the approximately 20,000 wells and intakes currently contained in our database. The TCEQ SWAP Program has been mapping source locations for the last decades using a variety of techniques from hand-drawn maps to Global Positioning System (GPS) technology.

If you feel that the mapped well location(s) provided with your system’s source water assessment report are incorrect, or if you would like to submit the location for a new well that wasn’t included in the report, please submit a location change request to TCEQ. The following information will explain how to submit a location change request to the TCEQ SWAP Program:

How Do I Submit a Location Change Request?

  1. Document in writing that the location provided with the source water assessment is incorrect or that you are submitting a location for a new well not previously mapped.
  2. Provide a new location to the TCEQ SWAP Program using one of the map types listed below.
  3. Send the new location to the address provided below.

Which Map Type Should I Use to Plot the New Location?

  • United States Geological Survey (USGS) 7.5-minute topographic map. This is the preferred base map for the TCEQ SWAP location effort as all of our procedures utilize the electronic or digital version of these maps.
  • Texas Department of Transportation (TxDOT) highway map for your county.
  • County map from a local government, 911 committee, commercial firm, or comparable source.
  • City street map developed by the city or a commercial firm.
  • Engineering plans of the facility. You will also need to note where the facility is located on one of the maps listed above.
  • An aerial photo or digital orthophoto quadrangle (DOQ) can also be used as a base map.
  • If applicable, you may also use a copy of the printed map provided with your assessment report to indicate a location change.

Where Can I Get One of the Maps Listed Above?

Digital maps may be downloaded FREE from the Texas Natural Resources Information System .

To obtain a copy of one of the USGS maps please contact the USGS:
USGS Store  
By phone: 1-888-ASK-USGS (1-888-275-8747)
Via U.S. Mail: USGS Information Services, Box 25286, Denver, CO, 80225.

NOTE: USGS maps are also available from local commercial firms that deal with surveying and mapping products. Check your local Yellow Pages for assistance.

To obtain a copy of one of the TxDOT maps, please contact TxDOT:
TXDOT Maps  
Via Telephone: 1-512-486-5014
Via U.S. Mail: Texas Department of Transportation, P.O. Box 5020, Austin, TX, 78763

Tips for Accurate Mapping

Accurate locations are critical to the success of the SWAP program. Please note the following tips when submitting a location change request:

  • Be as accurate and precise as possible by using existing intersections and other landmarks to zero in on the location.
  • Provide exact verbal descriptions when applicable, such as, "Well is 600 feet south of Avenue J and 130 feet west of Dover Street."
  • Label all mapped locations with the Public Water Supply Identification number and the Owner’s Name or Designation for the well, such as "Well #1" or "Kinney Street Well."
  • If providing a partial copy of a USGS 7.5-minute topographic map, please include the quadrangle name found on the bottom right corner of the map.

Where Do I Send the Well Location Change Request?

Send all maps and correspondence to:

Public Drinking Water Section
Source Water Assessment and Protection Program MC-155
P.O. Box 13087
Austin, Texas 78711-9958

For further assistance please contact us at the SWAP Program.