Houston-Galveston-Brazoria: Current Attainment Status

Note: This table is intended to provide a listing of designations and classifications for current, active National Ambient Air Quality Standards (NAAQS). While NAAQS which have been revoked by the U.S. Environmental Protection Agency (EPA) do not appear in this table, some anti-backsliding obligations may continue to apply for revoked standards. This table is to be used for informational purposes only and should not be used to determine regulatory requirements in any of the counties listed.

HGB Area: Attainment Status by Pollutant

*The EPA revoked the one-hour ozone standard and the 1997 eight-hour ozone standard in all areas, although some areas have continuing obligations under these standards. See ozone history for more information.

**Standard will be revoked one year after the effective date of final designations for the 75 ppb standard.

For more information on attainment status, visit the EPA's Green Book webpage regarding nonattainment areas for criteria pollutants.

HGB Nonattainment Areas

2015 Eight-Hour Ozone Standard Designations: Moderate Nonattainment, effective November 7, 2022 ( 87 FR 60897 )
On October 1, 2015, the EPA lowered the primary and secondary eight-hour ozone NAAQS to 0.070 parts per million (ppm) ( 80 FR 65292 ). A six-county HGB area including Brazoria, Chambers, Fort Bend, Galveston, Harris, and Montgomery Counties was designated nonattainment and classified marginal under the 2015 eight-hour ozone NAAQS, effective August 3, 2018. The HGB nonattainment area includes six of the eight counties that were designated nonattainment under the 2008 eight-hour ozone but does not include Liberty or Waller Counties, which were designated attainment/unclassifiable. The attainment date for the HGB marginal nonattainment area was August 3, 2021 with a 2020 attainment year. On October 7, 2022, the EPA reclassified the six-county HGB area from marginal to moderate nonattainment. The attainment date for the HGB moderate nonattainment area is August 3, 2024 with a 2023 attainment year.

2008 Eight-Hour Ozone Standard Designations: Severe Nonattainment, effective November 7, 2022 ( 87 FR 60926 ) 
Former 2008 Eight-Hour Ozone Standard Designations: Marginal Nonattainment, effective July 20, 2012 ( 77 FR 30088 ) and Moderate Nonattainment, effective December 14, 2016 ( 81 FR 90207  and 82 FR 3172 ).  
On March 27, 2008, the EPA lowered the primary and secondary eight-hour ozone NAAQS to 0.075 ppm ( 73 FR 16436 ). An eight-county HGB area including Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, and Waller counties was designated “nonattainment” and classified “marginal” under the 2008 eight-hour ozone NAAQS, effective July 20, 2012. The HGB area includes the same eight counties that were designated “nonattainment” under the 1997 eight-hour ozone standard. The attainment deadline for the HGB marginal nonattainment area was July 20, 2015. On May 4, 2016, the EPA published a final rule in the Federal Register granting a one-year attainment deadline extension for the HGB 2008 eight-hour ozone marginal nonattainment area to July 20, 2016 ( 81 FR 26697 ). Because the HGB area’s 2015 design value exceeded the 2008 eight-hour ozone NAAQS, the EPA published a final determination of nonattainment and reclassification of the HGB 2008 eight-hour ozone nonattainment area from marginal to moderate nonattainment on December 14, 2016, effective on the same date ( 81 FR 90207 ). The attainment deadline for the HGB moderate nonattainment area was July 20, 2018. On August 23, 2019, the EPA reclassified the eight-county HGB area from moderate to serious nonattainment. The attainment date for serious nonattainment areas was July 20, 2021 with a 2020 attainment year. On October 7, 2022, the EPA reclassified the eight-county HGB area from serious to severe nonattainment. The attainment date for severe nonattainment areas is July 20, 2027 with a 2026 attainment year.

1997 Eight-Hour Ozone Standard Designation: Severe Nonattainment, October 1, 2008 ( 73 FR 56983 )
Former 1997 Eight-Hour Ozone Standard Designation: Moderate Nonattainment, April 30, 2004 ( 69 FR 23858 )
An eight-county HGB area was designated “nonattainment” under the 1997 eight-hour ozone NAAQS, and classified as a moderate nonattainment area on April 30, 2004. The counties affected under this designation are Brazoria, Chambers, Fort Bend, Galveston, Harris, Liberty, Montgomery, and Waller. The EPA granted the governor’s request to voluntarily reclassify the HGB ozone nonattainment area from a moderate to a severe nonattainment area for the 1997 eight-hour ozone standard, effective October 31, 2008. The HGB area’s new attainment deadline for the 1997 eight-hour ozone standard was expeditiously as practicable but no later than June 15, 2019.

Status: The EPA published a final determination of attainment for the 1997 eight-hour ozone standard for the HGB area on December 30, 2015 ( 80 FR 81466 ). On August 18, 2015, the TCEQ submitted the Redesignation Substitute Report for the HGB 1997 Eight-Hour Ozone Standard Nonattainment Area to the EPA. This report fulfilled the EPA’s redesignation substitute requirements to lift anti-backsliding obligations for the 1997 eight-hour ozone NAAQS which was revoked effective April 6, 2015. The EPA published final approval of the redesignation substitute report on November 8, 2016 with an effective date of December 8, 2016 ( 81 FR 78691 ). On December 14, 2018, the TCEQ submitted a redesignation request and maintenance plan SIP revision to the EPA requesting formal redesignation of the HGB area to attainment for the 1997 eight-hour ozone NAAQS. On February 14, 2020, the EPA published final action on the SIP revision ( 85 FR 8411 ). The final rule terminates all anti-backsliding obligations for the HGB area for the 1997 eight-hour ozone NAAQS and approves the maintenance plan. The action did not redesignate the area to attainment, because the EPA has taken the position that it lacks the authority to redesignate areas to attainment under revoked standards.

National Ambient Air Quality Standards

The EPA sets National Ambient Air Quality Standards for six principal criteria pollutants: ground-level ozone, lead, carbon monoxide, nitrogen dioxide, sulfur dioxide, and particulate matter. 

Within one year after promulgation of a new or revised NAAQS for any pollutant, the governor must submit designation recommendations to the EPA for all areas of the state. The EPA must then promulgate the designations within two years of promulgation of the revised NAAQS. Areas that do not meet (or contribute to ambient air quality in a nearby area that does not meet) the NAAQS are designated “nonattainment.” Areas that meet the NAAQS are designated “attainment,” and areas that cannot be classified based on the available information, “unclassifiable.”

For ozone, the federal Clean Air Act establishes nonattainment-area classifications ranked according to the severity of the area’s air-pollution problem. These classifications—marginal, moderate, serious, severe, and extreme—translate to varying requirements with which Texas and nonattainment areas must comply.