The Texas Water Development Board is charged by the Texas Legislature with measuring and calculating flows in streams and to conduct studies, investigations, and surveys of the occurrence, quantity, quality and availability of surface water in Texas. To accomplish these objectives, the TWDB partners with several data providers to obtain and verify water-related data, including historical data that is not available online.
In particular, we'd like to acknowledge the following data providers:
United States Geological Survey (USGS)
The very first USGS streamgage in Texas was installed in 1889 on the Rio Grande near El Paso. The State-Federal Cooperative Program for Water Resources Investigations started shortly thereafter with the first jointly funded gage being installed in 1915. This program continues to fund the collection of streamflow and reservoir level data. In Fiscal year 2012, the funding agreement provides support for 59 streamflow gages and 43 reservoir level gages. The list of lakes currently monitored by the USGS can be found here. In addition, historical reservoir Elevation-Area-Capacity curves for many lakes were supplied by the USGS Texas Water Science Center.
In February 2011, TWDB staff identified a list of streamflow and reservoir level gages that were likely to lose funding in fiscal year 2012. Gages on that list were selected to minimize damage to TWDB’s ability to report on reservoir and streamflow conditions statewide. USGS created a website to make stakeholders aware that unless other funding was obtained, data would not be available from the listed gages after the end of fiscal year 2011. As of early August 2011, USGS has obtained funding from other local parties to continue data collection from 3 streamflow and 11 lake level gaging sites that have been removed from the fiscal year 2012 joint funding agreement with TWDB.
International Boundary Water Commission (IBWC)
Historical and current reservoir levels, area, storage and Texas/Mexico ownership data are provided by the the U.S. Section of the IBWC for Lake Falcon and Lake Amistad. The IBWC is the legal repository of data related to these lakes for treaty purposes and official versions of the datasets should be obtained directly from them.
United States Army Corps of Engineers (USACE)
Historical and current reservoir levels, area, storage are provided by the USACE for Caddo Lake, Pat Mayse Lake and Lake Texoma.
United States Bureau of Reclamation (USBR)
Historical and current reservoir levels, area, storage are provided by the USBR for Elephant Butte Lake.
Lower Colorado River Authority (LCRA)
Historical and current reservoir levels are provided by the LCRA for Lake Buchanan, Inks Lake, Lake Travis, Lake Austin and Lake LBJ.
TWDB Hydrographic Survey Program
The Elevation-Area-Capacity curves from TWDB hydrographic surveys have been incorporated into the area and storage estimates on this website to provide the best estimates possible.
Since 1993, the TWDB Hydrographic Survey Program has been conducting volumetric and sedimentation surveys of Texas Reservoirs. Over 100 unique reservoirs have been surveyed over the last two decades. Even so, many reservoirs have not been resurveyed in the decades since their construction, some since before the 1950's. The storage capacity of many of these reservoirs was originally estimated by analyzing available topographic maps of limited accuracy. In addition, over time, reservoir capacity is lost to sedimentation. With population and statewide water use increasing, current estimates of reservoir capacity for statewide water planning purposes is essential.