Max Speed limit values in miles per hour. This data is an extract from the Geospatial Roadway Inventory Databse (GRID), which is TxDOT's system for managing roadway assets in Texas.Note: Extracts from GRID are made on a regular basis and reflect the state of the data at that moment. Assets on routes that are in the process of being edited may be affected.Update Frequency: 1 MonthsSource: Geospatial Roadway Inventory Database (GRID)Security Level: PublicOwned by TxDOT: TrueRelated LinksData Dictionary PDF [Generated 2025/04/24]

The TxDOT Roadway Inventory is a statewide dataset of attribute data routed to TxDOT's roadway network linework using linear referencing. Roadways are dynamically segmented whenever a single attribute changes, resulting in a highly segmented network that can be queried and filtered for specific attribute values. Attributes such as functional system, traffic counts, surface type, speed limits and many more are contained within. This layer is published annually based on end-of-year data that is reported to the Federal Highway Administration. This layer is highly segmented and thus in a different format than most of our regularly published datasets, which are segmented based on a single attribute. The TxDOT Roadway Inventory layer can also be found on txdot.gov and TxDOT’s Open Data Portal. This product is created annually by the Transportation Planning and Programming Division at TxDOT in the Data Analysis, Mapping and Reporting Branch for internal and public use. Last Revision: 08/27/2025Roadway Inventory Specifications 2024 AGO OverviewTxDOT Roadway Inventory Specifications 2024 PDF link in AGO Update Frequency: 1 YearsSource: Geospatial Roadway Inventory Database (GRID)Security Level: PublicOwned by TxDOT: TrueRelated LinksData Dictionary PDF [Generated 2025/04/24]Update Frequency: 1 YearsSource: Geospatial Roadway Inventory Database (GRID)Security Level: PublicOwned by TxDOT: TrueRelated LinksData Dictionary PDF [Generated 2025/08/27]

VITAL SIGNS INDICATOR Time Spent In Congestion (T7)

FULL MEASURE NAME Congested delay on regional freeways

LAST UPDATED May 2017

DESCRIPTION Time spent in traffic congestion – also known as congested delay – refers to the number of minutes weekday travelers spend in congested conditions in which freeway speeds drop below 35 mph. Total delay, a companion measure, includes both congested delay and all other delay in which speeds are below the posted speed limit.

DATA SOURCE Texas Transportation Institute (unpublished analysis) 2011 Used for freeway ratio calculation

Texas Transportation Institute Urban Mobility Scorecard 2014 http://mobility.tamu.edu/ums/

U.S. Census Bureau: Intercensal Estimates http://www.census.gov/popest/data/intercensal/

U.S. Bureau of Labor Statistics: Metro Area Employment http://www.bls.gov/sae/

CONTACT INFORMATION vitalsigns.info@mtc.ca.gov

METHODOLOGY NOTES (across all datasets for this indicator) Delay statistics only include freeway facilities and rely upon INRIX traffic data. They reflect delay on a typical weekday, which is defined as Tuesday through Thursday during peak traffic months. Delay statistics emphasize recurring delay - i.e. consistent delay greater than 15 minutes on a specific freeway segment. Congested delay is defined as congestion occurring with speeds less than 35 mph and is commonly recognized as inefficient delay (meaning that the freeway corridor is operating at speeds low enough to reduce throughput - as opposed to speeds greater than 35 mph which increase throughput). Data sources listed above were used to calculate per-capita and per-worker statistics; national datasets were used for metro comparisons and California datasets were used for the Bay Area. Top congested corridors are ranked by total vehicle hours of delay, meaning that the highlighted corridors reflect a combination of slow speeds and heavy traffic volumes. Historical Bay Area data was estimated by MTC Operations staff using a combination of internal datasets to develop an approximate trend back to 1998. The metropolitan area comparison was performed for the combined primary urbanized areas (San Francisco-Oakland and San Jose) as well as nine other major metropolitan areas' core urbanized area. Because the Texas Transportation Institute no longer reports congested freeway delay or total freeway delay (focusing solely on total regional delay), 2011 data was used to estimate 2014 total freeway delay for each metro area by relying upon the freeway-to-regional ratio from 2011. Estimated urbanized area workers were used for this analysis using the 2011 ratios, which accounts for slight differentials between Bay Area data points under the regional historical data and the metro comparison analysis. To explore how 2016 congestion trends compare to real-time congestion on the region’s freeways, visit 511.org.