Texas Maps

Digital Data Availability Summary

Click for local parcel information. Map courtesy Digital Map Store

Why is marine cadastral data important for conservation and marine spatial planning?

Marine Cadastral Data Management

The Nature Conservancy’s 2010 Nationwide Comparative Assessment of State-level Marine Cadastral Data in Texas included an interview with the Texas General Land Office (GLO) and a review of relevant Internet sites. The GLO provided information about Texas’s marine data needs and marine cadastral management and completed an inventory (pdf) of state-level marine cadastral data.1

State Data Management: The Texas State Geographic Information Council maintains the Texas Natural Resource Information System (TNIRS) that provides access to state data sets. The GLO is responsible for managing state uplands and state coastal waters. The GLO web site has a considerable amount of information on coastal waters and submerged lands management data sets.

Marine Cadastre and Supporting Data

Cadastral Reference System: The energy industry, including oil, gas and (more recently) wind, has a strong presence in Texas coastal waters. As a result, Texas has a submerged lands tract grid, the Original Texas Land Surveys (OTLS), which is used for leasing and permitting in coastal waters. The OTLS varies in size, ranging from three square miles offshore to one square mile near shore. In the estuaries the OTLS is smaller and the orientation can vary. The OTLS tracts can be further subdivided into rectilinear parts of varying dimensions. The OTLS tracts begin offshore at the Submerged Lands Act Boundary and approach but do not tie to the shoreline. Resource management codes attached to the OTLS tracts indicate to oil and gas companies the resources that must be protected or restrictions that will apply. Some of these codes are from the Priority Protection Areas for Oil Spill Response, which is based on field data about endangered species.

Supporting Reference Data

Shorelines and Bathymetry: Shorelines maps are not specifically available from the state although shorelines of various scales can be acquired from NOAA Shoreline Data Explorer. The GLO site does have a Shoreline of Texas with Environmental Sensitivity Index Classification (sensitivity of shoreline habitats to oil contamination and removal) that is available for download. Bathymetry is available from TNIRS.

Coastal Imagery: Coastal imagery is available from TNIRS. This is mostly one-meter NAIP2 that is organized by county in the catalog. It is likely that high-resolution data exists in many of the counties; they will need to be individually contacted to determine availability (see local parcel information, below).

Marine Jurisdictional and Submerged Lands Boundaries: Marine Jurisdictional Boundaries are available from GLO under State Tracts with Resource Management Codes that include state, county and municipal boundaries. The Submerged Lands Act Boundary or offshore state boundary and the State Tracts layer are available for download. These layers can be used to build a general coverage of coastal submerged lands.

Ownership, Leases and Other Authorizations: State ownership extends from MHW to three marine leagues. The extent of state ownership is regularly updated as coastline changes using orthophotos or other sources. When beaches erode and the land becomes submerged, those lands become state lands. In some cases, such as with Navigation Districts, ownership of submerged lands has been transferred by the state legislature to municipalities or an independent government agency. Counties do not own submerged lands, although they may have some limited jurisdiction for policing and management. Oil and gas leases and pooling agreements are also mapped (where wells are close to lease boundaries and oil or gas field extends under two or more tracts). Sand and beach nourishment must be permitted through the GLO. The Army Corps of Engineers needs GLO permits for dredging. GLO provides the Land Office Interactive Land/Lease Mapping Systems. This interactive tool displays Original Texas Land Survey (OTLS) boundaries, state-owned lands, upland and coastal leases, oil/gas wells, and the latest coastal imagery.

Marine Managed Area: The GLO siteprovides coverages of Coastal Management Program Data for state-owned tracts in offshore waters and coastal bays, with codes added that reflect restrictions and concerns associated with leasing of these tracts.

Local Parcel Information: The state does not compile local government parcel data but it is available for some counties. It will be necessary to contact the counties individually to determine their status (see local parcel information, below).

GIS Portals

• Coastal Natural Resources Inventory Program. Data from a variety of sources to assist oil spill response. (web site)
• Texas General Land Office (GLO). Significant GIS data resources for identifying ownership and leasing information along the Texas coast and Gulf of Mexico are listed below.3 Full catalog is worth consulting for additional information on designated uses, jurisdictions, protected areas, habitats, and other environmental information. They provided four online mapping tools: TGLO Interactive Land/Lease Mapping Service, Energy Land Lease Inventory System, Oil Spill Responders Mapping Tool, and Beachwatch Interactive Map Tool. (web site)
• Texas Natural Resources Information System (TNRIS). State clearinghouse for natural resource data. Base map layers and digital orthophotos available for download or though ArcIMS service to GIS software. (web site)

Reference and Supporting Data

Cadastral Reference Grid

Shorelines

Coastal Imagery

Bathymetry

Marine Jurisdictional Boundaries

Submerged Lands Boundaries 

Ownership

Submerged Lands Parcels

General Property and Parcel Data

Public and Conservation Lands

Leases and Other Use Authorizations

Aquaculture and Shellfish

Other Use Authorizations

Marine Managed Areas

Local Parcel Information

All Counties

Aransas County (web site)

Brazoria County (web site)

Calhoun County (web site)

Cameron County (web site)

Chambers County (web site)

Galveston County (web site)

Harris County (web site)

Jackson County (web site)

Jefferson County (web site)

Kenedy County (no web site)

Kleberg County (web site)

Matagorda County (web site)

Nueces County (web site)

Orange County (web site)

Refugio County (web site)

San Patricio County (web site)

Victoria County (web site)

Willacy County (no web site)

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