Development of a GIS Coverage of Impaired Streams in Texas Presented by Samantha Hon CE 394K Nov. 19, 2002

Overview Introduction Introduction Purpose Purpose Method Method Progress to-date Progress to-date Future Work Future Work

Introduction Clean Water Act, amended 1987 Clean Water Act, amended 1987 –Water bodies must be “fishable and swimmable” Impaired water bodies – EPA Section 303(d) List (299 water bodies for 2002 Draft list) Impaired water bodies – EPA Section 303(d) List (299 water bodies for 2002 Draft list)

Introduction Impaired water bodies – TMDLs (Total Maximum Daily Load) Impaired water bodies – TMDLs (Total Maximum Daily Load) Implement TMDLs – Best Management Practices Implement TMDLs – Best Management Practices

Purpose Project for TxDOT Project for TxDOT TxDOT TxDOT –Potential discharger –Stormwater runoff from highways and roads Develop GIS coverage of impaired streams using ArcGIS Develop GIS coverage of impaired streams using ArcGIS –Determine where present or future infrastructure can contribute to impairment

Method Basemap of watersheds (HUCs) in Texas Basemap of watersheds (HUCs) in Texas –Overlay with coverage of streams and rivers, lakes, and highways and roads 303(d) list data in Excel format 303(d) list data in Excel format –Convert to.dbf file to import into ArcGIS

Method Join 303(d) list table with the streams and lakes coverages in the basemap Join 303(d) list table with the streams and lakes coverages in the basemap Query by pollutant in ArcMap Query by pollutant in ArcMap –Find out what streams impaired by what type of constituent –Determine which road/highway crosses impaired stream

Progress Basemap of Texas with HUCs, and streams and lakes from TCEQ Basemap of Texas with HUCs, and streams and lakes from TCEQ

Progress Problem Problem –Not all streams listed in 303(d) list available in the TNRCC streams and lakes coverage –Need to find more complete coverage of streams

Progress

Progress

Progress Problem Problem –No common field –Need to manually add a field, Seg_ID, to the new, complete stream coverage

Progress Example of output – Query by Pathogens Example of output – Query by Pathogens

Progress

Future Work Input new field into attribute table for the complete stream coverage Input new field into attribute table for the complete stream coverage Use new, more complete stream coverage and append to 303(d) list table Use new, more complete stream coverage and append to 303(d) list table Overlay map of highways and roads Overlay map of highways and roads