How's the Water?

The Houston-Galveston region is rich in water resources, with more than 16,000 miles of streams and shoreline that feed into one of the most productive estuaries in the United States, providing the region with a wealth of ecological, economic, and recreational assets. These water resources are shared among 7.2 million people for recreation, commercial fishing, shipping, and other industrial uses. With another 3 million people expected to move to the area over the next 20 years, the strain on these water resources will increase.

The Houston-Galveston Area Council (H-GAC) Clean Rivers Program ( Clean Rivers Program | Houston-Galveston Area Council (H-GAC) ) conducts water quality monitoring and assessment to determine the health of water bodies throughout the region. H-GAC does this through a coordinated effort with local partners and the Texas Commission on Environmental Quality (TCEQ). Along with analysis of this monitoring data, H-GAC assesses factors and activities impacting water quality. Information and recommendations on what individuals, industry, and local governments can do to make improvements and preserve local water bodies now and in the future are provided through public education and outreach organized by H-GAC. Clean Rivers Program data provides support for all watershed-based planning activities in the region.

Improving water quality requires more than the efforts of just one person or group of people. Progress is made when many stakeholder groups work together to manage water quality. The H-GAC Clean Rivers Program continues to coordinate the work of multiple stakeholder groups resulting in positive effects on water quality in the region.

Five appendices are provided to help readers understand the complexities involved in conducting data analyses on area water bodies.

The H-GAC Clean Rivers Program is considered a model program throughout the state, thanks in large part to its coordinated approach to water quality monitoring. The H-GAC Clean Rivers Program facilitates water quality discussions with decision-makers and water quality partner agencies in the region through the Clean Rivers Program Basin Steering Committee and the Regional Monitoring Workgroup and conducts ambient water quality monitoring, 24-hour dissolved oxygen monitoring, and targeted bacteria monitoring.

The H-GAC Clean Rivers Program covers all or a portion of 15 counties (Austin, Brazoria, Chambers, Colorado, Fort Bend, Galveston, Grimes, Harris, Liberty, Matagorda, Montgomery, San Jacinto, Walker, Waller, and Wharton), four basins (Brazos-Colorado Coastal Basin, San Jacinto River Basin, San Jacinto-Brazos Coastal Basin, and Trinity-San Jacinto Coastal Basin), and Bays and Estuaries.

The H-GAC Clean Rivers Program provides baseline data for many water quality studies and projects within the 15-county monitoring area at more than 400 sampling sites collected by H-GAC and six local partners:

•  City of Houston Health Department 

•  City of Houston Drinking Water Operations 

•  Environmental Institute of Houston (University of Houston-Clear Lake) 

•  Harris County Pollution Control Services 

•  San Jacinto River Authority (Lake Conroe and The Woodlands Divisions) 

•  Texas Research Institute for Environmental Studies (Sam Houston State University) 

Other agencies contributing data used by the Clean Rivers Program include:

•  Texas Commission on Environmental Quality 

•  United States Geological Survey  (flow gage data)

The H-GAC Clean Rivers Program Steering Committee ( Clean Rivers Program Committees | Houston-Galveston Area Council (H-GAC) ) serves as the primary forum for discussion of various water quality issues raised through the assessment process. The committee advises staff on all administrative matters related to the Clean Rivers Program, including work plan and budget development, monitoring of progress toward project milestones, and review of the draft and final basin reports and other work items.

In 2023, the Steering Committee (Clean Rivers Program Committees | Houston-Galveston Area Council (H-GAC)) discussed key components of the Clean Rivers Program, including

• draft and final review of 2023 Basin Highlights Report;

• proposed changes to fiscal year 2024 regional coordinated monitoring schedule;

• updates on watershed protection plans and total maximum daily loads /implementation plans using Clean Rivers Program data; and

• public outreach activities for 2023.

The Regional Monitoring Workgroup ( Clean Rivers Program Committees | Houston-Galveston Area Council (H-GAC) ), composed of field and laboratory staff from each of the local Clean Rivers Program partner agencies, meets quarterly to provide updates on individual monitoring programs, discuss quality assurance issues, and discuss solutions to common problems found in field and/or laboratory settings.

Each spring, the workgroup holds a coordinated monitoring meeting to discuss data gaps and set the monitoring schedule for the coming fiscal year. Changes in the schedule are determined using data analysis, recommendations of field or laboratory personnel, and recommendations or requests related to the needs of ongoing total maximum daily load implementation plans, watershed protection plans, TCEQ permitting, or changes to budgets.

All monitoring is conducted under a TCEQ-approved Multi-Basin Quality Assurance Project Plan ( Multi-Basin Quality Assurance Project Plan | Houston-Galveston Area Council (H-GAC) ). All laboratories used by Clean Rivers Program participants are accredited through the National Environmental Laboratory Accreditation Program (NELAP).

TCEQ established aquatic life use designations for all segments and many tributaries in the state. These designations (exceptional, high, intermediate, limited, and minimal) are based on established numerical criteria and are highly dependent on the desired use of the water body, the sensitivities of aquatic communities expected to be found in those water bodies, and the local physical and chemical characteristics of the water bodies. One criterion used to evaluate aquatic life use is dissolved oxygen, which includes a 24-hour minimum and a 24-hour average. Routine monitoring generally collects dissolved oxygen grab samples only, which may identify concerns and impairments. Impairments must be verified through deployment of multi-parameter data sondes to determine current 24-hour minimums and averages.

H-GAC, with the help of the Environmental Institute of Houston at the University of Houston Clear Lake (EIH), conducts 24-hour dissolved oxygen monitoring to verify or determine the extent of the dissolved oxygen concern or impairment of 10 segments or tributaries. In FY2024, monitoring is being conducted at the following sites:

11118 – Cedar Bayou Above Tidal downstream of FM 1942 (segment 0902)

11405 – Armand Bayou at Fairmont Parkway, Pasadena (segment 1113A)

12155 – Caney Creek Above Tidal downstream of Ashwood Rd/FM 3156 (segment 1305)

16475 – Robinsons Bayou at FM 270 in League City (segment 1101D)

16564 – Lake Madeline in Galveston (segment 2424B)

16675 – Unnamed Tributary of Buffalo Bayou at Glenwood Cemetery Rd in central Houston (segment 1013C). Site was dropped partway through FY2024 due to safety after construction altered the banks and channel.

16676 – Unnamed Tributary of Greens Bayou at Smith Rd, Houston (segment 1016D)

20721 – West Bernard Creek at Wharton CR 225 east of Hungerford (segment 1302B)

20723 – Mound Creek at Brazoria CR 450/Jackson Settlement Rd near West Columbia (segment 1302E)

21734 – Brushy Bayou at FM 213 in Brazoria County (segment 1105E)

Monitoring of Robinsons Bayou, an Unnamed Tributary of Buffalo Bayou, an Unnamed Tributary of Greens Bayou, Armand Bayou, and Brushy Bayou are carry-over 24-hour dissolved oxygen monitoring sites from FY2023. Additional data are needed for TCEQ to determine whether these segments are supporting or not supporting their aquatic life use designations.

In 2021 and 2023, H-GAC contracted with the EIH and the Texas Research Institute for Environmental Studies (TRIES) at Sam Houston State University to conduct investigations of numerous assessment units (AUs) looking for contaminated dry-weather flows. This Targeted Bacteria Monitoring Project focuses on the region’s most prevalent pollutant – bacteria.  The Bacteria Implementation Group (BIG)  requested H-GAC produce a list of water bodies with the highest bacteria concentrations in the BIG project area to help identify bacteria (E. coli) sources within the H-GAC region. H-GAC performed a seven-year geometric mean analysis defining the severity of impairment of each AU within the region. As part of this project, H-GAC staff identified 12 AUs for field investigation. The AUs were selected by reviewing the highest geomeans identified. Staff then completed an assessment of accessibility of each AU and the feasibility of being able to effectively conduct monitoring of the AU. Funding for the Targeted Bacteria Monitoring Project was provided by the Clean Rivers Program and the Total Daily Maximum Load (TMDL) Program.

H-GAC and its subcontractors, EIH and TRIES, first conducted a windshield survey on each watershed. This survey served as a spatial assessment of the watershed and determined where hotspots of high bacteria concentrations existed along the water body and its tributaries. During the windshield survey, the field crew collected bacteria samples at easily accessible locations, such as major road crossings and public access points adjacent to the water body. Results from the survey aided in prioritizing intensive field investigations along the water body and tributaries of concern leading into the main segment. Both survey events (windshield survey and field investigation) were only conducted during dry weather following a 72-hour antecedent dry period.

For the field investigation, samples were collected upstream and downstream of any outfall categorized as permitted or >12 inches in diameter and the difference in results was compared, but samples were not collected directly from the outfall source. Any outfall that was judged to be “unpermitted” in the field was sampled directly at the source. All tributary samples were collected far enough into the flowing water so that mixing was not a factor. In instances where no potential sources were observed for an extended section of the water body, a single ambient reference sample was taken mid-stream.

The team created reports for each AU detailing methods and findings. In total, 108 samples were collected in all windshield surveys, 587 samples were collected within the field investigations, and 109 sites were referred to the proper authorities. In addition to referrals for specific outfalls, some referrals included areas where high bacteria levels were found in ambient samples without any flows observed from nearby potential sources. Individual reports detailing methods and findings are available on H-GAC’s website at  https://www.h-gac.com/getmedia/c480c536-d024-440e-b7a5-7b01552d7e2a/Targeted-Bacteria-Monitoring-Project-FY2022-2023. 

The Houston-Galveston region supports a population of more than 7 million residents and includes the fourth-largest city and third-most populous county in the nation. This concentration of people can place significant strain on the surface water quality in the region.

H-GAC Clean Rivers Program staff summarized water quality in the major watersheds of the region by calculating the percentage of the streams and shoreline miles, of both classified and unclassified water bodies, in the watershed where water quality impairments or concerns were identified by TCEQ in the 2022 Texas Integrated Report of Surface Water Quality ( https://www.tceq.texas.gov/waterquality/assessment/22twqi/22txir ). The Integrated Report evaluates the quality of surface water in Texas and is used as a tool to make decisions about water quality programs across the state. Water bodies are assigned to categories based on how well they meet the standards established to define and measure their quality. Water bodies can be designated as impaired by not meeting the standards or of concern, meaning they may not meet the standard in the future or a standard does not yet exist.

More than 89 percent of water body, stream or shoreline miles in the H-GAC Clean Rivers Program basins have a concern for or fail to meet one or more state water quality standards. The most common water quality indicators for the state water quality standards are bacteria, dissolved oxygen, and PCBs/dioxin. There are no water quality standards for nutrients (forms of phosphorus, ammonia, and nitrogen), but excessive concentrations are considered concerns.

Staff identified trends for the major water quality indicators in each watershed and included these in the 2024 Regional Water Quality Summary Chart (locally referred to as the Frog Chart), analyzing data collected from December 31, 2015, through December 31, 2022. Data from the most downstream station identified as being statistically representative within a classified segment and all available data in the bays and estuaries were analyzed. The bacteria geomean trend was calculated using the same seven-year period. Clean Rivers Program staff used nonparametric correlation analysis to detect trends. Trends were considered statistically significant if the p-value was below 0.05.

Trends identified include the following:

• The good news is even though most of the region’s water bodies do not meet one or more state water quality standards, about 56 percent have not seen further deterioration. 
• Eighteen percent of segments have shown improvement in bacteria levels with five percent of segments deteriorating over the seven-year period H-GAC selected for analysis.
• Areas in the Bacteria Implementation Group (BIG) implementation plan, which provides recommendations for bacteria reduction in the greater Houston area, have experienced a significant reduction in bacteria levels since 2005. The BIG, due to new TMDLs completed for the East and West Fork of the San Jacinto River, Armand Bayou, and Jarbo Bayou, and at the request of those watershed stakeholders, expanded to include those watersheds within the BIG. Members of the BIG requested that bacteria geometric mean trends continue to express the original area and the original area plus the expanded area trend lines.
• Two percent of segments have shown improvement in dissolved oxygen levels over the seven-year assessment period. Eleven percent of segments are getting worse.
• Thirty-three percent of segments have shown improvement in nutrient levels over the seven-year assessment period. Just 22 percent have shown deterioration in nutrient levels. Trend analysis for nutrients was done for each nutrient parameter, but the reported trends are a composite of the nutrients analyzed. The segment summaries identify which nutrient parameters are of concern for those water bodies.

Improved water quality in the region may be attributed to several factors, including

• increased investigations of wastewater collection systems and resulting line repairs and facility improvements;
• improved regulation and maintenance of on-site sewage and wastewater treatment facilities;
• increased preservation of natural habitat and installation of water quality features in detention basins; and
• heightened public awareness and public participation.

Forty-four percent of stream miles in the Houston-Galveston region are affected by high levels of bacteria and are listed as impaired or of concern for contact recreational use. High bacteria concentrations can cause swimmers or waders who come into contact with the water to suffer from skin infections or mild to severe gastrointestinal illness. No bays are impaired for enterococci bacteria but may be impaired for oyster harvesting due to elevated concentrations of fecal coliform bacteria.

Bacteria concentrations are measured to ensure a water body is safe for recreation. Enterococci is collected in tidal water bodies, while E. coli is collected in freshwater. Both are found in the digestive tracts of people and animals and are used as indicators of the presence of sewage and pathogens (such as infectious bacteria, viruses, and protozoans).

TCEQ evaluates the results of bacteria testing to determine whether a water body is safe for contact recreational activities like swimming. A type of average called a geometric mean is calculated for a seven-year period. If the geometric mean is higher than the water quality standard, the water body may be considered impaired for contact recreation activities. H-GAC uses a moving seven-year bacteria geometric mean to show the change in bacteria levels in the region. Bacteria relative geomeans show the magnitude of impairments for water bodies, meaning how many times above the state standard the bacteria concentrations are, on average over the seven-year period. Because two different types of indicator bacteria with different water quality standard levels are analyzed, H-GAC standardizes the results so both can be displayed on the same graph. The moving geometric mean for all H-GAC Clean Rivers Program monitoring stations is above the standard; however, despite an increase in population and other pressures, bacteria levels have remained stable.

Sources of bacterial contamination include

• Sanitary sewer overflows
• Untreated wastewater treatment facility (WWTF) releases
• Failing on-site sewage facilities (septic systems)
• Fecal waste from livestock, pets, feral hogs, and wildlife

Seventeen percent of stream miles in the region are affected by low levels of dissolved oxygen (DO). Oxygen depletion in water bodies can create uninhabitable environments for fish and other aquatic life crucial to the region’s economy.

DO levels are measured to ensure a water body can support aquatic life. Higher levels of DO can contribute to more abundant and diverse aquatic species. DO levels fluctuate naturally based on season, time of day, and human influences. Sudden or prolonged decreases in DO could result in fish kills.

Dissolved oxygen can be negatively impacted by

• high concentrations of nutrients causing algal blooms;
• sediment from construction sites;
• overgrazing of livestock;
• stream channel modification and development; and
• reduced riparian tree cover.

Two percent of freshwater streams, 70 percent of tidal streams, and 76 percent of bays in the region are impaired for PCBs and dioxin. No lakes in the region are impaired. Because fish and shellfish can accumulate contaminants from the waters they live in, they are monitored closely by federal, state, and local governments, and bans and advisories are issued when consumption may be a risk to human health.

The U.S. Environmental Protection Agency (EPA) website recommends “when contaminant levels are unsafe, fish and shellfish advisories help people make informed decisions about where to fish or harvest shellfish. Advisories recommend that people limit or avoid eating certain species of fish and shellfish caught in certain places.”

The Texas Department of State Health Services Seafood and Aquatic Life Unit protects consumers from contaminants, disease, or other health hazards transmissible or found in fish or shellfish. They issue advisories and bans, and provide easy-to-use maps, including the online Texas Fish Consumption Advisory Viewer ( www.dshs.texas.gov/seafood/TFCAV.aspx ), to identify current water body-specific health advisories for fish and shellfish for all Texas waters.

Fish and shellfish consumption bans and advisories can also be found on the Texas Parks and Wildlife Department website ( www.tpwd.texas.gov/regulations/outdoor-annual/fishing/general-rules-regulations/fish-consumption-bans-and-advisories ).

For more information about PCBs/dioxin in area water bodies, see the Water Quality Summary Chart.

Thirty-four percent of stream miles in the region exceed the state screening levels for nutrients, including nitrate, ammonia, and phosphorus.

Nutrients are chemical substances that promote the growth of aquatic organisms. TCEQ evaluates the amount of these nutrients (which include various forms of nitrogen and phosphorus) as part of their assessment process.

In high concentrations, nutrients can contribute to low dissolved oxygen levels and may result in unsightly or toxic algal blooms. Algae also produce chemicals which can cause taste and odor problems in drinking water.

Sources of nutrient pollution include

• fertilizer runoff from lawns and agricultural fields;
• manure;
• sewage treatment plant discharges;
• stormwater runoff; and
• failing on-site sewage facilities.

Statewide Development of Nutrient Criteria

In 2012, TCEQ established a Nutrient Criteria Development Advisory Workgroup tasked with developing nutrient criteria, including strategies for developing criteria, types of criteria, categorization of water bodies, and additional data needs to ensure water bodies throughout the state are meeting their designated uses. Criteria continue to be adjusted for specific regions rather than using a one-size-fits-all criteria. Only 39 lakes or reservoirs in the state currently have numeric criteria for nutrients. Lake Houston and Lake Conroe, the two drinking water supply reservoirs in the region, have narrative criteria only. The workgroup continues to hold public meetings and seeks stakeholder and subject-matter expert input for developing nutrient criteria. See  Nutrient Criteria Development - Texas Commission on Environmental Quality. 

The Clean Rivers Program provides data for review and summary of ambient water quality conditions for the 56 segments in the four basins and bays and estuaries monitored and assessed by H-GAC and its Clean Rivers Program partners.

Regional Water Quality Summary Chart

To illustrate the region’s impairments or concerns, the Clean Rivers Program compiled the Regional Water Quality Summary Chart, a comprehensive summary chart of regional water quality for six parameters for 55 of the 56 water body segments in the four basins and bays and estuaries (No data were collected for Cedar Lakes-segment 2442). The chart also illustrates whether the impairment or concern is trending for the better or worse or has stayed the same.

The numbers in the cells in the chart represent the percent of total segment length that is impaired or of concern for each parameter. Cells without numbers (blanks) represent stream segments that are currently meeting state standards but may be improving or degrading for each parameter. Trend columns indicate whether the segment is improving, deteriorating, or staying the same (indicated by grey cells) for four parameters.

In addition to the 2024 Regional Water Quality Summary Chart, water quality information is provided as Regional Water Quality Summaries for each of the 56 segments.

The data provided on the Water Quality Summary Chart and Water Quality Summaries are derived from water quality monitoring data collected by H-GAC and Clean Rivers Program partners between December 2015 and December 2022.

Qualifiers are used to describe the portion of segments where water quality issues exist. A few parts means 33 percent or less of a segment; some parts means 34-66 percent of a segment; and most parts means 67 percent or greater of a segment. If only a single portion of a tributary is listed, it is the only portion with the concern.

Each segment summary contains information on the selected segment watershed, a list of associated tributaries, water quality impairments and concerns designated by the TCEQ, and any plans developed to address those issues. For more details about the segments’ impairments and concerns, see the Water Quality Summary Chart. Information about watershed projects can be found in the Watershed Project Summaries section of this report.

For information on specific impairments or concerns for a segment down to the AU level, review the TCEQ 2022 Integrated Report of Surface Water Quality  (https://www.tceq.texas.gov/waterquality/assessment/22twqi/22txir ). Fish Consumption Advisories mentioned in the Water Quality Summary Map are issued by the Texas Department of State Health Services.

In addition to the 2024 Regional Water Quality Summary Chart, water quality information is provided as Regional Water Quality Summaries for each of the 56 segments in the interactive map below.

Elevated levels of bacteria continue to be the biggest water quality issue throughout the region. High bacteria levels can inhibit safe contact recreation and the harvest of oysters. With the guidance of local stakeholders, nearly two dozen watershed-based plans, completed or in progress, have been designed to reduce bacteria levels and bring those water bodies with elevated levels of bacteria into compliance with state standards.

Fish Consumption Advisories, a result of elevated levels of PCBs/dioxin in fish and crab tissue, continue to be an important issue in the region’s bays and many tidal water bodies. Federal, state, and local agencies and organizations continue to identify major sources of these toxic chemical compounds and develop procedures to remediate them

Low levels of dissolved oxygen and increasing levels of nutrients are tracked through routine monitoring. Many of the best management practices being put in place through watershed-based plans to reduce bacteria levels have a positive impact by raising dissolved oxygen levels and reducing nutrients.

The H-GAC Clean Rivers Program generates approximately 70 percent of data used for water quality decision making for the region by TCEQ. The data are used to help with the development and implementation of TMDLs, watershed protection plans, and other local actions. The ability to understand the developing health of the water bodies throughout the region is paramount. H-GAC will continue to work with state and local stakeholders to find ways to do more systematic and focused monitoring in areas with elevated bacteria to locate and remove chronic sources.

Every two years, TCEQ submits the Texas Integrated Report of Surface Water Quality to the EPA for approval. The report provides an assessment of existing water quality in the state and an overview of past and proposed water pollution reduction efforts. Clean Rivers Program monitoring data is included in the Integrated Report.

The Texas 303(d) List, part of the Integrated Report  (www.tceq.texas.gov/waterquality/assessment) , identifies water bodies that are impaired or threatened due to pollutant(s). The list may be used by planning agencies to prioritize watershed projects and acts as a catalyst for planning and mitigation strategies to address impairments and concerns, including bacteria, dissolved oxygen, nutrients, and PCBs/dioxin.

After a water body is added to the 303(d) List, there are two primary watershed-based planning paths for resolution available:

• developing a watershed protection plan, or
• determining a total maximum daily load and developing an implementation plan

H-GAC and other regional partners are actively involved in both types of watershed-based plans.

Watershed protection plans are developed with local stakeholders to address water quality issues in a community’s water bodies. The plans are based on an EPA template to identify causes and sources of pollution, establish improvement goals, identify feasible and effective measures to address pollution sources, and establish ways to evaluate the effectiveness of the efforts. While the development of a watershed protection plan is usually due to a water body’s inability to meet one or more state water quality standards, the plans can be implemented as a preventative measure. Watershed protection plans are not limited to a specific impairment and can consider a wide range of stakeholder concerns related to water. Implementation activities outlined by watershed protection plans are voluntary, contain no regulatory requirements, and generally focus on nonpoint sources of pollution such as urban, agricultural, and natural runoff. Watershed protection plans use Clean Rivers Program data to determine water quality priorities.

Watershed protection plans approved or in development for the H-GAC region are described below. More information about H-GAC watershed protection plans is available at  Watershed-Based Plans | Houston-Galveston Area Council (H-GAC) .

Total Maximum Daily Load/Implementation Plans

Total maximum daily load (TMDL) is a regulatory process triggered when a water body is placed on the 303(d) List. The total maximum daily load calculates the maximum amount of a single pollutant that a water body can receive and still meet water quality standards. To address the pollutant of concern, stakeholders complete an implementation plan that contains a series of recommended regulatory and/or nonregulatory best practices, identifies funding sources and implementing partners, and determines a project timeline. Clean Rivers Program data provides support for focusing water quality priorities.

More information about H-GAC total maximum daily loads and implementation plans is available at   Watershed-Based Plans | Houston-Galveston Area Council (H-GAC) .

On-site Sewage System Management 

Regular maintenance and inspection of on-site sewage facilities protects public and environmental health, increases system longevity, and enhances private property use and value. In conjunction with the Clean Rivers Program, H-GAC offers programs ( https://h-gac.com/on-site-sewage-facilities ) to help reduce bacteria levels in water bodies near these facilities.

In the Homeowner Education Course, residents receive an overview of both types of on-site sewage systems (septic or aerobic), information on system maintenance and inspection, and details on available resources to maintain, repair, and replace aging systems. The course provides homeowners the basics of on-site sewage system maintenance and visual inspection but does not provide for or allow homeowners to inspect their own aerobic system in place of professional inspections as part of a regular maintenance contract.

 The Wastewater Assistance Program provides funding for the repair and replacement of failing on-site sewage systems (septic or aerobic). Funding is available to homeowners who meet certain income parameters. No matching funds are required. This program is funded through a Supplemental Environmental Project through TCEQ, with additional funding from the Harris County District Attorney’s Office. Funding from corporate donations is also available for this project.

The On-Site Sewage Facility Information System Mapping Tool contains data on the locations of permitted on-site sewage facilities by age, authorized agent, permitting authority, number of permits per square mile, and likely locations of unpermitted systems. Updates to the mapping tool are conducted as part of the annual Water Quality Management Plan.

Water Quality Management Plan

H-GAC conducts water quality management planning as part of a Clean Water Act Section 604(b) grant program funded by the EPA through TCEQ. The annual Water Quality Management Plan Update ( https://www.h-gac.com/water-quality-management-planning ) describes a series of data collection, special study, and coordination activities completed through this project. The purpose of these activities is to provide data and analysis regarding wastewater infrastructure, watershed planning, and sources or nonpoint source pollution that affect water quality in the region

Data acquired and assessed through this project include geospatial data for wastewater treatment plant outfalls and service area boundaries, self-reported effluent monitoring data, and occurrences of sanitary sewer overflows. Updates to the on-site sewage facility information system mapping tool are coordinated through this project.

The quality-assured data from this project are used extensively to inform decisions in multiple watershed projects and programs, such as the Clean Rivers Program, Bacteria Implementation Group, and numerous watershed protection plan and total maximum daily load projects. Data are also made available to project partners and H-GAC member entities for use in their water quality planning activities

Coastal Communities Outreach Program

H-GAC’s Coastal Communities Outreach and Education Program improves education and outreach about water pollution in Brazoria, Chambers, Galveston, and Matagorda counties by bridging the gap between the needs identified by communities and the implementation measures in watershed-based plans.

The program helps small communities without municipal separate storm sewer system permits engage residents in education and outreach that promotes behavior change to reduce the potential for water pollution. These communities typically lack financial and staff capacity to develop, launch, implement, and maintain public outreach campaigns.

The project focuses on four pillars of behavior change: pet waste management; fats, oils, and grease disposal; litter and illegal dumping; and on-site sewage facility repair and maintenance. H-GAC maintains a website for coastal communities ( www.coastalcommunitiestx.com ) that offers resources and tools for planning and implementing residential education and outreach campaigns. Local governments, utility districts, schools, civic organizations, homeowner associations, apartment managers, and other volunteers can use the tools to engage residents in positive behavior change. H-GAC also worked with local stakeholders to develop and pilot materials to specifically address fats, oils, and grease disposal in apartment complexes.

In 2023, H-GAC efforts in the program focused on identifying areas in communities where vulnerable populations overlap with high numbers of on-site sewage facilities and who may experience barriers to either receiving current program outreach materials or attending educational workshops. By working with local community partners already interacting with these residents, the program will pilot new materials and strategies to try and overcome identified barriers and more effectively engage the residents on the topic of on-site sewage facility repair and maintenance.

Galveston Bay Coalition of Watersheds

The Galveston Bay Coalition of Watersheds is an informal group of stakeholders from four watershed areas in Brazoria and Galveston counties: Bastrop, Dickinson, Highland, and Jarbo bayous. The Coalition serves as a long-term sustainable group that shares effort and cost of implementing watershed -based plans across multiple watersheds with similar identified pollution sources, easing the burden for individual communities. The Coalition is coordinated by the  Texas Community Watershed Partners  of Texas AgriLife.

Public outreach is a cornerstone of the H-GAC Clean Rivers Program and is considered in all projects that staff implement. Outreach efforts seek to inform and educate local stakeholders about water quality issues and empower them to take an active role in the health of local water bodies

Outreach Priorities

Stakeholder engagement, education, and outreach takes several forms in the H-GAC Clean Rivers Program. Outreach and education activities are often coordinated with other water resources programs and projects in the region. Coordination among these projects allows the Clean Rivers Program to reach a broad audience while tailoring information to the needs of a specific geographic or project boundary.

The following is an overview of key stakeholder engagement and outreach activities from 2023.

Texas Stream Team

The H-GAC Texas Stream Team program ( www.h-gac.com/texas-stream-team ), managed locally by the Clean Rivers Program, with support from the Galveston Bay Foundation, Bayou Preservation Association, and City of Sugar Land, trains and certifies volunteer water quality community scientists. There are 74 active monitoring stations in the four basins managed by H-GAC. Most sites collect the program’s Standard Core parameters, but thanks to the help of partners, some sites also collect E. coli bacteria samples, Advanced parameters, or Riparian Evaluation data. In 2023, trainings in Brazoria, Fort Bend, Harris, and Montgomery counties certified 20 new monitors.

Texas Stream Team data is found on the Water Resources Information Map ( www.h-gac.com/go/wrim/ ).

Texas Stream Team data are used to supplement professionally collected data and provide data in areas where professional monitoring does not take place. This monitoring is valuable to the Clean Rivers Program by helping identify areas with emerging water quality problems to determine where new professional monitoring might be needed.

H-GAC publishes a quarterly e-newsletter for monitors, interested governments, organizations, and residents.

Clean Waters Initiative

The Clean Waters Initiative ( https://www.h-gac.com/clean-water-initiative-workshops ), a workshop series facilitated by H-GAC Clean Rivers Program staff, offers education and information to local governments, nonprofit organizations, landowners, and residents to help develop effective strategies to reduce pollution in local water bodies. The workshops provide an opportunity for diverse stakeholder groups to network.

In 2023, three workshops focused on conservation and riparian areas, stormwater programs and impaired waters, and volunteer water quality monitoring programs.

Water Resources Information Map

The Water Resources Information Map ( www.h-gac.com/go/wrim/ ) is an interactive mapping tool displaying all Clean Rivers Program professional and Texas Stream Team volunteer water quality monitoring sites in the region, with photos and data associated with each site. This tool, compatible with mobile devices, is available to anyone interested in current and historic water quality data, issues, and trends in the region.

River, Lakes, Bays ‘N Bayous Trash Bash

The Rivers, Lakes, Bays ‘N Bayous Trash Bash _®  ( www.TrashBash.org ), established by the H-GAC Clean Rivers Program and the Texas Natural Resource Conservation Commission in 1993, is the largest single-day water body cleanup in Texas. Trash Bash is managed by the Texas Conservation Fund, with support from the Gulf Coast Authority and a volunteer steering committee. H-GAC staff provide regional coordination for the event.

Trash Bash _®  promotes environmental stewardship of the Galveston Bay watershed through public education by using hands-on educational tools and developing partnerships between environmental, governmental, and private organizations. Since its inception, more than 119,000 volunteers have removed over 2,400 tons of trash. In 2023, 2,456 volunteers at 14 locations collected 40.51 tons of trash, 219 tires, and almost a half-ton of recyclable material while cleaning 108.2 miles of area shoreline. Approximately half the volunteers are under 18-years of age, and nearly a quarter participate in scouting.

In 2023, Trash Bash _®  held its 29th cleanup event and was a finalist in the Texas Environmental Excellence Awards in the Civic/Community category.

Other Education and Outreach Activities

H-GAC Clean Rivers Program staff attend public-facing education and outreach events to encourage residents of the region to adopt positive water pollution prevention behaviors in their daily lives.

For outreach events that have educational booths, staff select materials and messaging for each event from a collection of interactive exhibits H-GAC created with the help of grant funding from TCEQ and the Galveston Bay Estuary Program. Materials focus on common residential behaviors that can result in water pollution, with the primary focus on reducing bacterial levels in local water bodies. While Clean Rivers Program staff did not participate in many booth-style outreach events in 2023, they helped make sure the outreach materials still reached residents. All materials can be borrowed at no charge by groups wishing to talk about water quality in their communities, and seven complete sets of the materials are on long-term loan with partners for use at events throughout the year. The educational posters for the exhibits are available in English, Spanish, and Vietnamese.

Materials

• Pitch the Poop reinforces the need to pick up pet waste. Participants can win pet waste bag dispensers for dog leashes by playing the game;
• Defeat the Grease Monster demonstrates the effects of improper disposal of fats, oils, and grease on sanitary sewer pipes and on-site sewage facilities. Participants can win funnels and plate scrapers by playing the game;
• Turn Your Yard into a Sponge illustrates the pollutants contained in stormwater runoff from residential home surfaces (roof, yard, impervious surfaces). Participants can receive a brochure on how to prevent stormwater pollution at home; and
• Fish Me from the Watershed focuses on proper disposal of trash. Participants decide where to dispose of common types of trash (landfill, recycling bin, other recycling options, household hazardous waste) and if this is a viable item for reusing or reducing. Participants can receive a refrigerator magnet, donated by the H-GAC Solid Waste Management program, to remind them to check  www.Earth911.com  for proper disposal or recycling options.

H-GAC staff 

In addition to using the H-GAC outreach materials above, Clean Rivers Program staff participated in several outreach events in 2023 that were not in an outreach booth format.

• Provided educational support for a new Trash Bash cleanup site on Greens Bayou using the educational materials;
• Provided steering committee representation for the Trash Summit, a regional collaborative to develop a marine debris reduction action plan  (www.donttrashagoodthing.org) ;
• Partnered on the Trash Free Texas Adopt-a-Spot project  (www.trashfreetexas.org) , a statewide collaborative through the EPA Trash Free Waters Program to consolidate litter adopt-a-spot programs into one interactive mapping application;
• Discussed bacteria in area bayous and related outreach opportunities at the Bayou Preservation Association watershed and subcommittee meetings; and
• Used Clean Rivers Program data for planning at Basin 11 and Basin 13 bacteria reduction project and regional watershed protection plan stakeholder meetings.

Online

H-GAC’s water quality programs and activities are listed on the agency and program websites and social media. Water resources staff also monitor a dedicated e-mail account for questions and more information.

These sources include the following:

• Houston-Galveston Area Council website ( www.H-GAC.com )
• Trash Bash Website ( www.TrashBash.org )
• Coastal Communities Website ( www.coastalcommunitiestx.com )
• Email ( waterresources@h-gac.com )
• H-GAC Facebook ( www.facebook.com/HouGalvAreaCog )
• H-GAC also has YouTube, X (formerly Twitter) and Instagram pages
• Trash Bash Facebook ( www.facebook.com/TrashBash/ )

FIELD PARAMETERS

• Dissolved Oxygen (DO)
• Instantaneous Flow
• pH
• Salinity
• Secchi Transparency
• Specific Conductance (SpCond)
• Temperature

CONVENTIONAL PARAMETERS

• Ammonia-Nitrogen (NH3-N)
• Chloride (Cl-)
• Chlorophyll-a (Chl-a)
• Nitrate-Nitrogen (NO ₃ -N)
• Nitrite-Nitrogen (NO ₂ -N)
• Total Phosphorus (TP)
• Sulfate (S ₂ O ₄ )
• Total Kjeldahl Nitrogen (TKN)
• Total Suspended Solids (TSS)

BACTERIA PARAMETERS

• Escherichia coli (E. coli)
• Enterococci

ORGANIC PARAMETERS

• Dioxin
• Polychlorinated Biphenyls (PCBs)

Water Quality Parameters, Potential Impacts, and Sources

The Water Quality Technical Primer is provided as an overview of general water quality terminology. In combination with the Glossary, the Technical Primer provides background and defines terminologies and methodologies used to acquire, analyze, and report the data that is presented in the Basin Highlights Report.

THE FEDERAL CLEAN WATER ACT

The US Clean Water Act establishes the basic structure for regulating pollutant discharges, pollutant loadings in water, and regulating surface water quality standards. The goal of the Clean Water Act is “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters” (33 U.S.C. §1251(a)).

Amendments to The Clean Water Act in 1977:

• Established the basic structure for regulating pollutant discharges into the waters of the United States;
• Gave the US Environmental Protection Agency (EPA) the authority to implement pollution control programs, such as setting wastewater standards for industry;
• Maintained existing requirements to set water quality standards for all contaminants in surface waters;
• Made it unlawful for any person to discharge any pollutant from a point source into navigable waters, unless a permit was obtained under its provisions;
• Funded the construction of sewage treatment plants under the construction grants program; and
• Recognized the need for planning to address the critical problems posed by nonpoint source pollution.

POLLUTION

The Texas Administrative Code defines pollution as “the alteration of the physical, thermal, chemical, or biological quantity of, or the contamination of, any water in the state that renders the water harmful, detrimental, or injurious to humans, animal life, vegetation, or property or to public health, safety, or welfare, or impairs the usefulness or the public enjoyment of the water for any lawful or reasonable purpose.”

There are two categories of pollution: Point Source and Nonpoint Source Pollution.

Point Source pollution is any source of pollution that is subject to regulation and is permitted. An example of a point source is a permitted wastewater treatment facility effluent discharge.

Nonpoint Source (NPS) pollution is any source not subject to regulation, diffuse, and does not have a single point of origin or is not introduced into a receiving stream from a specific outfall. NPS pollution typically results from land runoff, precipitation, atmospheric deposition, drainage, seepage, or hydrologic modification.

TEXAS SURFACE WATER QUALITY STANDARDS

The Texas Surface Water Quality Standards (TSWQS) establish numerical and narrative goals to maintain the quality of streams, rivers, lakes, and bays throughout the state. Appendix A and Appendix D of the TSWQS establish the geographic boundaries and the appropriate standards for each body of water. The standards are developed to maintain the quality of surface waters. Standards ensure public health and enjoyment, protect aquatic life, and remain consistent with the sustainable economic development of the state. The Texas Commission on Environmental Quality (TCEQ) develops the TSWQS under the authorization of the US Clean Water Act and Texas Water Code. The TSWQS are codified in Title 30, Chapter 307 of the Texas Administrative Code. The standards are approved by the EPA.

The TSWQS are designed to:

• Designate the uses, or purposes, for which the state’s water bodies should be suitable;
• Establish numerical and narrative goals for water quality throughout the state; and
• Provide a basis on which TCEQ regulatory programs can establish reasonable methods to implement and attain the state’s goals for water quality.

The criteria adopted and incorporated into the standards are the allowable concentrations of pollutants in State, Territory, and authorized Tribal waters and are developed for the protection of aquatic life and human health. Impairments occur when water quality conditions do not meet the assigned uses or criteria as defined in the TSWQS.

DRAINAGE AREAS — BASINS, WATERSHEDS, AND SUB-WATERSHEDS

A watershed is a defined geographic area that water bodies flow through on the way to a common body of water. Basins are larger geographic areas generally containing one or more watersheds. A river basin is a collection of watersheds drained by a major river and tributaries. A coastal basin is a collection of watersheds adjacent to the coastline that water flows through on its way to the ocean. Typically, coastal basins are between and bound by two major river basins and a bay or other outlet to the ocean. Watersheds can be broken down into even smaller drainage areas, which are referred to as sub-watersheds. For example, a sub-watershed could be defined as the drainage area of a small creek, stream, or portion of a stream that is part of the drainage area for a tributary, which is part of a major river drainage basin.

WATER BODIES, SEGMENTS, AND ASSESSMENT UNITS

The term water body is used to refer to any mass of water. A water body can be contained in a lake or a bay, or flow, such as a river, creek, or bayou. TCEQ divides water bodies in the state into distinct segments that generally represent natural watersheds and are intended to have similar chemical, physical, and hydrological characteristics. Each segment is assigned a four-digit code. The first two digits identify the river basin, and the last two digits identify the segment. Segments can be either classified or unclassified.

Classified Segments

A classified segment is a water body (or portion of a water body) that is individually defined in the TSWQS. Typically, classified segments are major waterways. Site specific numerical criteria are developed to evaluate the use and overall water quality of a classified segment. The parameters evaluated include bacteria, nutrients, and dissolved oxygen. Uses include aquatic life use and recreations use (discussion later in the primer).

Unclassified Segments

Unclassified segments are often tributaries of classified segments. These segments are usually assessed based on the criteria of the classified segment into which they flow. However, some unclassified segments have been assigned specific water quality standards in the TSWQS. Unclassified segments are assigned the same four-digit code as the classified segment and a letter that is specific to that water body.

Assessment Units (AUs)

For assessment purposes, each segment is subdivided into hydrologically distinct units, or assessment units (AUs). AUs are the smallest geographic areas of a water body that can support a designated or site-specific use. A segment may have one or multiple AUs, depending on water quality conditions or flow in different sections of the water body. Each AU has the same four or five-digit code as the segment followed by an AU identifier (e.g., _01, _02, etc.). If there are multiple AUs, the assessment units will generally be in sequential order (e.g., 1007D_01, 1007D_02, etc.). Each AU is evaluated separately as part of the assessment.

For example, Sims Bayou Above Tidal (1007D) is divided into three AUs. The red dots represent monitoring stations. Monitoring stations have been placed on the downstream and upstream ends of each AU in 1007D. Tributary 1007A has one monitoring station close to the confluence with the parent stream 1007D.

WATER QUALITY AND DESIGNATED USES

As defined in the TSWQS, a water body can be assigned specific uses including aquatic life, public water supply, and contact recreation use. Designated uses typically have corresponding numeric criteria listed in the TSWQS. General criteria apply across the entire state, but if sufficient information is available for a specific water body, the site-specific standards may be developed.

Aquatic Life Use

Aquatic life use (ALU) is determined by the amount of dissolved oxygen and the abundance and diversity of species. Aquatic life use consists of five categories: minimal, limited, intermediate, high, and exceptional. In Texas, water bodies not specifically listed in Appendix A or D of the TSWQS are presumed to have a high aquatic life use and corresponding dissolved oxygen criteria. This use is assessed using 24-hour dissolved oxygen data along with nekton and macrobenthic invertebrate community evaluations.

Public Water Supply Use

Public water supply (PWS) use includes an evaluation of chloride, sulfates, and total dissolved solids in the water body. Criteria for these parameters are set so that public water supplies can treat and deliver water of acceptable quality.

Recreational Use

Recreational use refers to how safely a water body can support activities that involve the possibility of ingesting or coming into contact with water. If activities are likely to result in ingestion of water (wading, swimming, diving, tubing, surfing), bacteria levels need to be lower than the water quality standard to minimize risk. The TSWQS protects human health by setting numeric criteria in a water body relative to the types of recreational activity occurring on that water body. Fecal indicator bacteria levels are measured to determine risk. Criteria are expressed as the number of bacteria per 100 milliliters (mL) of water in terms of colony-forming units (CFU), most probable number (MPN), or other applicable reporting measures. The presence of fecal indicator bacteria in waters suggests that human and animal wastes may be reaching the assessed waters. In freshwater, the indicator organism is Escherichia coli (E. coli). Enterococci bacteria are the indicator for tidal water bodies.

There are five categories of recreational use, which are based on the type and frequency of recreation.

• Primary Contact Recreation 1 (PCR1) – Activities that are presumed to involve a significant risk of ingestion of water (e.g., wading by children, swimming, water skiing, diving, tubing, surfing, hand fishing, and whitewater kayaking, canoeing, and rafting).
• Primary Contact Recreation 2 (PCR2) – Water recreation activities, such as wading by children, swimming, water skiing, diving, tubing, surfing, hand fishing, and whitewater kayaking, canoeing, and rafting, that involve a significant risk of ingestion of water but that occur less frequently than for PCR1 due to physical characteristics of the water body or limited public access.
• Secondary Contact Recreation 1 (SCR1) – Activities that commonly occur but have limited body contact incidental to shoreline activity (e.g. fishing, canoeing, kayaking, rafting, and motor boating). These activities are presumed to pose a less significant risk of water ingestion than PCR1 or PCR2 but more than secondary contact recreation 2.
• Secondary Contact Recreation 2 (SCR2) – Activities with limited body contact incidental to shoreline activity (e.g. fishing, canoeing, kayaking, rafting, and motor boating) that are presumed to pose a less significant risk of water ingestion than SCR1. These activities occur less frequently than SCR1 due to physical characteristics of the water body or limited public access.
• Noncontact Recreation (NCR) – Activities that do not involve a significant risk of water ingestion, such as those with limited body contact incidental to shoreline activity, including birding, hiking, and biking. NCR use may also be assigned where primary and secondary contact recreation activities should not occur because of unsafe conditions, such as ship and barge traffic.

Primary contact recreation is the presumed recreational use in Texas water bodies unless there is evidence to show that the water body is not used for primary contact recreation. A Recreational Use Attainability Analysis (RUAA) is necessary to change the presumed use of a water body.

WATER QUALITY MONITORING

Surface Water Quality Monitoring (SWQM) Program

TCEQ’s Surface Water Quality Monitoring (SWQM) Program evaluates the physical, chemical, and biological characteristics to ensure that it is suitable for general or designated uses. Water quality is monitored and evaluated in relation to human health concerns, ecological conditions, and designated uses. Data collected under the SWQM program are used by TCEQ to provide a basis for effective policies that promote the protection, restoration, and wise use of the state’s surface water.

Surface water samples are collected for assessment purposes following the methodologies outlined in TCEQ’s Surface Water Quality Monitoring Procedures Volume 1: Physical and Chemical Monitoring Methods (TCEQ Publication RG-415) (colloquially referred to as “SWQM Procedures”). The guidelines outlined in the SWQM

Procedures manual document the methods and the quality assurance procedures that must be used to demonstrate that data collected by monitoring personnel across the state are of a known and adequate quality. All data collected by H-GAC and its partners are collected following SWQM procedures.

Water quality data, including data collected under SWQM and the Clean Rivers Program, are stored in the Surface Water Quality Monitoring Information System (SWQMIS). This database is used to enter, manage, track, and report on water quality-related data.

Coordinated Monitoring Schedule (CMS)

The Coordinated Monitoring Schedule (CMS) is the combined schedule for all surface water quality monitoring in Texas. Monitoring entities within a basin or region meet annually to establish and coordinate monitoring schedules to ensure appropriate coverage, reduce duplication of effort, and better use available resources.

The CMS lists:

• Monitoring stations
• Collecting Entities (CE)
• Submitting Entities (SE)
• Monitoring Type (MT)
• Parameters
• Monitoring frequency

The Coordinated Monitoring Schedule is available online at  https://cms.lcra.org 

Quality Assurance Project Plan (QAPP)

H-GAC’s Clean Rivers Program Quality Assurance Project Plan (QAPP) describes H-GAC’s quality assurance policies, management structure, and procedures used to implement the quality assurance requirements for the Clean Rivers Program. These policies and procedures are necessary to verify and validate data collected for the Clean Rivers Program. The QAPP is reviewed and approved by TCEQ to help ensure that all data generated are of known and documented quality, deemed acceptable for their intended use and that the data have been collected and managed in such a way as to guarantee its reliability. Only quality-assured data may be used for water quality assessments or other regulatory purposes. H-GAC’s QAPP documents are available on H-GAC’s website at  Multi-Basin Quality Assurance Project Plan | Houston-Galveston Area Council (H-GAC) 

Monitoring Types

Monitoring activities may be divided into the following categories:

• Routine Monitoring
• Special-Study Monitoring
• Permit-Support Monitoring
• Systematic Monitoring

The type of monitoring conducted by the Clean Rivers Program is usually routine, meaning it is monitoring that is scheduled in advance without intentionally trying to target any certain environmental condition, with samples being collected regardless of the conditions encountered. Routine monitoring includes field measurements (DO, pH, specific conductance, temperature), conventional chemical parameters (nutrients, chloride, sulfate), bacterial measurements (E. coli or enterococci), and flow measurements (if applicable for that water body). Please see Appendix C: Water Quality Parameters for a list of the parameter.

Another monitoring type conducted by the Clean Rivers Program is biased monitoring (monitoring targeted to a season, time, or condition) measurements, such as 24-hour DO. In this procedure, a data sonde (a water quality monitoring device that calculates and records field parameters) is deployed to measure DO every 15 minutes for 24 hours. After the deployment period, the data is analyzed, and the 24-hour average and absolute minimum are calculated. The DO average and absolute minimum are used to assign an ALU category to a water body. For example, exceptional aquatic life use has a 24-hour average of 6.0 mg/L and an absolute minimum of 4.0 mg/L. Biased monitoring can be part of a special study or permit support monitoring.

ASSESSMENT OF WATER QUALITY DATA

The provisions of Sections 305(b) and 303(d) of the Clean Waters Act require TCEQ to provide the Texas Integrated Report for Clean Water Act Sections 305(b) and 303(d) (Integrated Report) to the EPA every two years. The report contains a list of water bodies evaluated, water bodies assessed by basin, impaired water bodies (303(d) List), water bodies of concern, water bodies either newly listed or removed from the 303(d) List, and other supporting information

For the assessment, TCEQ evaluates data collected during a seven-year period. The time frame is extended to 10 years (if needed) to attain the minimum number of data points needed for the assessment. Each assessed water body is identified as:

• Fully Supporting – At least 10 data points (20 for bacteria) are available for an assessment, and the water body meets TSWQS or supports designated uses
• Of Concern – There are two levels of concern, CN and CS. CN means there is concern for near nonattainment of the TSWQS based on numeric criteria. A concern status of CN indicates that standards are not being met, but there is insufficient data to fully assess the water body. CS means that there is a concern for water quality based on screening levels. Screening levels are used when there is not a defined standard (as with nutrients) and are derived from statistical distributions of statewide water quality monitoring data, with the 85th percentile for each applicable parameter is used as the screening level criteria.
• Impaired – Data indicates that the water body does not meet standards. Impaired water bodies are placed on the 303(d) List.

When a water body is determined to be impaired, several things must happen:

• The water body must be listed on the 303(d) List:
• An evaluation must be undertaken to determine what is preventing the water body from supporting its designated use(s) or if the use(s) are appropriate.
• Steps must be taken to either remedy the problem, collect additional data, or evaluate which uses are appropriate for the water body. These steps may include additional monitoring, development of a Total Maximum Daily Load (TMDL) or Watershed Protection Plan (WPP), or a review of the water quality standards.

After assessment, water bodies are placed into one of five categories (with subcategories). These categories indicate the water quality status of the water body. These categories (as well as subcategories), and their descriptions, are:

1. Attaining all water quality standards and no use is threatened.

2.    Attaining some water quality standards and no use is threatened; and insufficient data and information are available to determine if the remaining uses are attained or threatened.

3.    Insufficient data and information are available to determine if any water quality standard is attained.

4.    Water quality standard is not supported or is threatened for one or more designated uses but does not require the development of a TMDL.

4a        TMDL has been completed and approved by EPA.

4b        Other pollution control requirements are reasonably expected to result in the attainment of the water quality standard in the near future.

4c        Nonsupport of the water quality standard is not caused by a pollutant.

5.    The water body does not meet applicable water quality standards or is threatened for one or more designated uses by one or more pollutants.

5a        A TMDL is underway, scheduled, or will be scheduled.

5b        A review of the water quality standards for the water body will be conducted before a management strategy is scheduled.

5c        Additional data and information will be collected before a management strategy is scheduled.

5n        Water body does not meet its applicable chlorophyll-a criterion for reservoirs, but additional study is needed to verify exceedance

A previously assessed AU with insufficient data available during the assessment period for the most recent Integrated Report results in a carry-forward of the impairment listing from the previous report.

MANAGEMENT MEASURES FOR IMPAIRED WATER BODIES

If sufficient data is available to determine that a water body is impaired and does not meet standards, a management measure can be implemented to address the impairment.

• A Total Maximum Daily Load (TMDL) is a method used to determine the amount (load) of a pollutant an impaired water body can receive daily and still meet water quality standards and designated uses. After a load is calculated for the pollutant sources, an implementation plan (I-Plan) is drafted by the water body’s stakeholders outlining management measures to be used to return the target pollutant to the calculated load. An I-Plan’s management measures are usually voluntary actions but can, if recommended by stakeholders, include regulatory actions.
• A Watershed Protection Plan (WPP) is a community- and stakeholder-driven framework that uses a holistic/watershed approach to address potential sources of impaired water bodies. The plan is developed with community involvement, and the measures to reduce pollutants are voluntary.
• A Use Attainability Analysis (UAA) determines if the natural characteristics of a water body cannot attain the currently designated uses and/or criteria. Natural characteristics include temperature, pH, DO, diversity of aquatic organisms, amount of streamflow, and physical conditions such as depth. If there is a consensus among stakeholders and resource agencies that a presumed or designated use may not be appropriate for a water body, a UAA may be conducted to determine the most appropriate use(s).
• A Recreational Use Attainment Analysis (RUAA) is used to determine if contact recreation use occurs in a water body. A water body may have physical characteristics or limited public access that would not warrant a contact recreation use designation.

The identification of long- and short-term trends is important to many stakeholders, and these trends are important components of H-GAC’s work, particularly in relation to the evaluation and revision of regional monitoring efforts and priorities. H-GAC staff used several methods of analyses to characterize surface water quality in the H-GAC region. Trend analysis can identify cases where the value of a water quality parameter is changing over time. Statistical tests are performed to distinguish statistically significant trends from random and seasonal variation. While it might seem reasonable to use all the data available for these analyses, as the amount of data increases the likelihood of finding a statistically significant but unimportant trend also increases. To minimize this, H-GAC performed trend analysis on the most recent 7 years (December 31, 2015 – December 31, 2022) of Texas Commission on Environmental Quality (TCEQ)-validated data to highlight recent trends in water quality in the region.

All data management and statistical analysis were performed using Statistical Analysis System (SAS). Complete details of data selection, preparation, and analysis can be found in the SAS code, which is available upon request.

Data Selection and Processing

For analyses in this report, H-GAC staff selected water quality data collected between 12/31/2015 and 12/31/2022 from data downloaded from Surface Water Quality Monitoring Information System (SWQMIS). All data used for these analyses were collected under a TCEQ-approved Quality Assurance Project Plan (QAPP). Qualified data (data added to SWQMIS with qualifier codes that identify quality, sampling, or other problems that may render the data unsuitable) were excluded from the download.

Variables in each dataset were transformed as appropriate, and new variables were created to facilitate analysis and graphical display of results. In some cases, data from two or more STORET (method) codes were combined because the results obtained from each method can be considered equivalent. Any data collected at a depth greater than 0.3 meters, or not collected under a routine ambient monitoring program, were deleted.

Censored data (data reported as < [parameter limit of quantitation (LOQ)]) were transformed to a value of one-half the parameter LOQ associated with the data, with some important exceptions. Because nutrient LOQs have been lowered over time, the presence of data censored at many different LOQs in the same dataset poses several problems. If the data for a given parameter are censored at values well above a later, lower LOQ value, trend analysis could suggest a trend where no real water quality trend is present. There is no ideal solution to this problem. Editing the censored data alone would limit, but not eliminate, false trends. In cases where some of the data reflected use of a lower LOQ than the current H-GAC Clean Rivers Program LOQ, values were transformed to one-half of the H-GAC Clean Rivers Program

LOQ to minimize the identification of trends caused by changing analytical methods. H-GAC does not believe the impact from this transformation is significant. The impact of this analysis would be most pronounced for parameter trends typically found at concentrations at or near the LOQ in that specific water body.STORET Codes and Parameters for Trend Analysis

Data Selection for Trend Analysis

H-GAC staff performed segment-level trend analysis on a 7-year data series (if available) from all data in the segment. Trends were also evaluated at the AU level to assess any changes and confirm results.

Trend Analysis Methodology

The first stage of trend analysis looked for temporal patterns for both segments and AUs. To identify these patterns, nonparametric correlation analysis (Kendall’s tau-b) of the parameter value with the sample collection date was used to identify correlations that were significant at p <0.05. These potential trends were then evaluated with up to four other methods. Simple linear regression of the natural log of the parameter value on the time variable was performed for all data in the subset selected by H-GAC for trend analysis. Flow-adjusted trends were obtained through correlation of residuals from LOESS (locally weighted least squares) regression in cases where instantaneous flow data were available. If there were no temporal gaps in the time-series (missing years, consistently missing seasons), seasonal Kendall/Sen Slope estimation/Theil regression was run. If more than 15 percent of the data were censored at the analytical LOQ, survival analysis (Tobit analysis in SAS PROC LIFEREG) was performed.

Selected statistically significant trends were produced for segments and AUs for each watershed described in this report. If the trend is described as Increasing or Decreasing, the calculated p-value is below the threshold of 0.05 selected by H-GAC. Trends identified as Stable have a calculated p-value greater than 0.05. When evaluating the results of several trend analyses of a given parameter, H-GAC placed the most weight on the Kendall correlation because nonparametric methods are insensitive to outliers in the time series. However, if Kendall correlation differed from the results of seasonal trend analysis or flow-weighted analysis, the data were further evaluated. If no flow data were available, the flow-adjusted trend appears as Not Calculated (indicating no flow data is available) or Insufficient Data (indicating only one flow value exists and a correlation could not be calculated). If the seasonal Kendall/Sen Slope trend was not calculated due to gaps (missing seasons) in the time series, the seasonal Kendall trend appears as Not Calculated. Survival analysis was only applied in those cases where the amount of censored data could bias the results of the other methods. H-GAC set the threshold at 15 percent or more censored data. If fewer than 15 percent of the data were censored, survival analysis was not performed, and the trend appears as Not Applicable on output results.

Trend Analysis for the Regional Water Quality Summary (“Frog Chart”)

The Regional Water Quality Summary, colloquially known as the “Frog Chart,” is an index constructed by H-GAC to capture the degree of impairment/concerns for selected parameters (Dissolved Oxygen, bacteria, Chlorophyll-a, nutrients, PCBs/Dioxin, and a category for Other impairments) in each classified or unclassified segment. H-GAC’s assessment of the health of these water bodies is a stream length-weighted summary of the impairments/concerns in each segment and is weighted based upon the percentage of the segment exhibiting the impairment or concern. This index is the basis for assigning a frog count to each segment. Segments are assigned from zero to five frogs, with the higher frog count indicating fewer impairments and concerns and better overall water quality.

In 2015, H-GAC staff compiled a subset of stations in classified segments believed to be most representative of segment water quality by selecting one to three stations that were statistically representative of a given parameter in a given segment. Means and standard deviations of parameter values are calculated for each station, and those stations with means and standard deviations closest to the overall mean and standard deviation for the segment and parameter combination were selected. Preference was given to stations where stream flow was measured, and final selections were reviewed for reasonableness. In most cases, the station, or stations at the most downstream location of the segment was the most statistically representative. Selection relied on SAS procedures PROC MEANS and PROC RANK. The same subset of stations has been used since 2015 to allow consistent comparisons across regional water quality summaries created for different years.

A conservative trend analysis was performed using seven years of recent data (12/31/2015 – 12/31/2022) at the selected representative monitoring stations in the classified portion of each watershed to detect trends at the watershed level for the H-GAC Regional Water Quality Summary (“Frog Chart”). Trends were identified by nonparametric correlation analysis and simple linear regression. Because nonparametric methods are less sensitive to extreme values in the data than parametric techniques like linear regression, trends that were suggested by linear regression analysis alone were not included in the char

Trends for the “Frog Chart” analysis were considered statistically significant if the p-value was below 0.05, which is the standard significance level used in most applications.

Some adjustments to the final frog count were made by H-GAC staff based on best professional judgment, in order to capture attributes not fully revealed by the SAS data analysis.

A Note on Statistical Significance

H-GAC feels that selecting all results with p-values ≤0.10 produces too many real, but unimportant, trends. In part, this is due to the large amount of data collected for our region; the more data one analyzes, the more likely it is that one will find a result  and identify a “trend” that is statistically different from randomness (“no trend”). For example. 0.0545 rounds to 0.055, which in “arithmetic rounding” becomes 0.06 when expressed as one significant figure.

Clean Rivers Program Staff

Contract Administration, Special Studies Coordination, Data Analysis and Assessment Todd Running Water Resources Program Manager 713-993-4549  Todd.Running@h-gac.com  

Quality Assurance, Special Studies Coordination, Data Analysis and Assessment Jean Wright Senior Planner, Clean Rivers Program Monitoring Coordinator 713-499-6660  Jean.Wright@h-gac.com  

Data Analysis and Assessment Jessica Casillas Senior Planner, Clean Rivers Program Data Manager 713-993-4594  Jessica.Casillas@h-gac.com 

Water Quality Monitoring and Outreach Kendall Guidroz Senior Planner & Texas Stream Team Volunteer Coordinator 713-993-2469  Kendall.Guidroz@h-gac.com  

Water Quality Monitoring Elling Mann Program Support Specialist 713-993-4546  Elling.Mann@h-gac.com 

Additional Staff Support:

Total Maximum Daily Load/Implementation Plan Steven Johnston Principal Planner 832-681-2579  Steven.Johnston@h-gac.com 

Watershed Protection Plans Rachel Windham Senior Planner 713-993-2497  Rachel.Windham@h-gac.com 

Water Quality Management Plans Bill Ervin Senior Planner 713-993-2487  Bill.Ervin@h-gac.com 

Watershed Protection Plans Cornell Evans, Jr. Planner 713-499-6666  Cornell.Evans@h-gac.com 

Report Chief Editor Andrea Tantillo Principal Communication Coordinator 832-681-2507  Andrea.Tantillo@h-gac.com 

StoryMap Developer Molly Eskelson GIS Analyst 832-681-2674  Molly.Eskelson@h-gac.com 

Funding Acknowledgement

Prepared in cooperation with the Texas Commission on Environmental Quality.

The preparation of this website was financed through funding from the Texas Commission on Environmental Quality