Navasota River Below Lake Limestone Watershed Protection Plan

The Navasota River watershed is located in East-Central Texas in the Brazos River basin. Lake Limestone impounds the River causing a hydrological divide in the watershed. The majority of the watershed is rural and urbanization is largely confined to the Bryan/College Station area in Brazos County. Land use/land cover in the watershed is dominated by hay/pasture land and hardwood forests. Watershed characteristics and good land management yield a productive watershed that supports abundant livestock and wildlife. The Navasota River and several tributaries were first listed as impaired on the 2002Texas Integrated Report (Texas 303(d) List)for elevated E. coli concentrations. Low dissolved oxygen (DO) in Duck Creek also resulted in a water quality impairment. Additionally, concerns for elevated nutrients and chlorophyll-a, and depressed DO also exist in several locations. These impairments and concerns signify the need to improve water quality and protect the resource for future uses and users. To address this need, watershed stakeholders were organized to development the Navasota River Below Lake Limestone Watershed Protection Plan. Through this process, impairment causes and sources were identified and evaluated allowing stakeholders to make informed decisions regarding management recommendations to mitigate source contributions in a cost-effective manner. E. coli comes from numerous sources in the watershed; however, stakeholders recommended management strategies for five sources that can be feasibly managed. These include feral hogs, humans, livestock, pets, and stormwater. Recommended management measures focus on preventing E. coli from entering waterbodies by retaining it on the landscape or removing it from the watershed. For livestock, this includes practices to modify where cattle are located in the watershed such as cross fencing to improve grazing management, providing alternative water sources, and prescribed grazing. For feral hogs, this includes reducing food supplies and physically removing hogs from the watershed. Pet focused management relies on proper disposal of pet waste. Human E. coli loading in watershed comes from failing on-site sewage facilities (OSSFs) and malfunctions in wastewater conveyance systems. To address these issues, replacing failing OSSFs and routine wastewater line inspections were recommended. Education outreach and delivery to raise awareness about water quality and how local actions affect the watershed is also recommended. This plan outlines recommended strategies that will reduce potential pollutant loading to the Navasota River and its tributaries when implemented. However, watershed conditions change over time. To account for this, the WPP is a living document that will evolve as needed through an adaptive management process. Ultimately, the Navasota River Watershed Protection Plan sets forth an approach to improve watershed resource stewardship that allows watershed stakeholders to continue relying on the watershed as their livelihood while also helping to restore the quality of its water resources

Application of Quantitative Microbial Risk Assessment and Bacterial Source Tracking to Assess the Associated Human Health Risks from Multiple Fecal Sources During Recreational Exposure in the Leon River Watershed

Applying a risk assessment framework, such as quantitative microbial risk assessment (QMRA), can be used to estimate the human health risk associated with recreation in a waterbody impaired for elevated levels of fecal indicator bacteria (FIB). Recent efforts to identify the sources contributing to a waterbody’s bacterial impairment have been facilitated by bacterial source tracking (BST) analysis for several watersheds in Texas, including the Leon River Watershed. A QMRA was conducted to calculate the human health risk for a recreational waterbody impacted by both human and non-human sources of fecal contamination. Waterborne reference pathogens were used to represent the different fecal contamination sources and the risk of a GI infection and illness. The GI illness risk for contact exposure to recreational waters within the Walnut Creek tributary of the Leon River Watershed were calculated for site LEO 2, with a geometric mean of 163 cfu 100 mL^-1, and the U.S. recreational standard of 126 cfu 100 mL^-1 for Escherichia coli (E. coli). Three different scenarios were modeled to estimate the potential risks of a GI illness in recreational waters impacted by different proportions of human and non-human sources of fecal contamination. The analysis found that: a) the dominant fecal source in a waterbody may not be the greatest contributor to the human health risk; b) risks associated with wildlife fecal contamination were significantly lower than that of the cattle/domestic animals and human fecal contamination; and c) while considering norovirus as a representative pathogen for human fecal contamination, the estimated risk was much higher. The results indicate that identifying the sources contributing to a bacterial impairment and conducting a QMRA for the recreational waterbody can greatly assist in developing site-specific standards, especially if the site is not predominantly impacted by human fecal contamination

Basin Approach to Address Bacterial Impairments in the Navasota River Watershed

The 2012 Texas Integrated Report – Texas 303(d) List identifies 11 impaired waterbody segments along the Navasota River due to Escherichia coli (E.coli) bacteria (Figure 1). The Clean Water Act (CWA) requires water bodies that are impaired for a specific parameter or condition, to be restored and their water quality maintained. Efforts to restore impaired waterbodies include additional monitoring, assessing the current standards and conditions of the waterbody, stakeholder outreach and education, and exploring opportunities for developing watershed restoration plans. Previous reports regarding the watershed have revealed E. coli levels to be elevated in specific tributaries since as early as 1999 (TCEQ 2013b; BRA 2011). The river’s elevated E.coli levels do not comply with the state’s recreational water quality criteria for primary contact recreation, which is established at 126 cfu/100 mL. Segment 1210A of the river, which lies above Lake Mexia, is an unclassified waterbody that has been named impaired by bacterial contamination since 2002. The Navasota River below Lake Mexia, segment 1253, is considered impaired for depressed dissolved oxygen (DO) because of frequent low water levels (BRA 2011). The project’s goals include: (1) characterize the current bacteria loading and sources for the watershed, (2) determine the necessary levels of loading reduction to restore the water body, (3) work with stakeholders to select and prioritize management measures necessary to restore the waterbody, and (4) develop a watershed protection plan for the Navasota River below Lake Limestone. This report discusses the climatic, physical, demographic, and hydrological conditions as well the potential sources of pollution within the watershed. The report also includes an assessment of current and historical conditions within the Navasota River watershed and aims to begin the process of defining its current bacteria levels. Information is largely presented on a watershed-wide basis; however, where appropriate and possible, information is discussed on a more refined scale.Texas Commission on Environmental Quality Contract Number 582-14-42129-0

Navasota River Below Lake Limestone Watershed Protection Plan

The Navasota River watershed is located in East-Central Texas in the Brazos River basin. Lake Limestone impounds the River causing a hydrological divide in the watershed. The majority of the watershed is rural and urbanization is largely confined to the Bryan/College Station area in Brazos County. Land use/land cover in the watershed is dominated by hay/pasture land and hardwood forests. Watershed characteristics and good land management yield a productive watershed that supports abundant livestock and wildlife. The Navasota River and several tributaries were first listed as impaired on the 2002Texas Integrated Report (Texas 303(d) List)for elevated E. coli concentrations. Low dissolved oxygen (DO) in Duck Creek also resulted in a water quality impairment. Additionally, concerns for elevated nutrients and chlorophyll-a, and depressed DO also exist in several locations. These impairments and concerns signify the need to improve water quality and protect the resource for future uses and users. To address this need, watershed stakeholders were organized to development the Navasota River Below Lake Limestone Watershed Protection Plan. Through this process, impairment causes and sources were identified and evaluated allowing stakeholders to make informed decisions regarding management recommendations to mitigate source contributions in a cost-effective manner. E. coli comes from numerous sources in the watershed; however, stakeholders recommended management strategies for five sources that can be feasibly managed. These include feral hogs, humans, livestock, pets, and stormwater. Recommended management measures focus on preventing E. coli from entering waterbodies by retaining it on the landscape or removing it from the watershed. For livestock, this includes practices to modify where cattle are located in the watershed such as cross fencing to improve grazing management, providing alternative water sources, and prescribed grazing. For feral hogs, this includes reducing food supplies and physically removing hogs from the watershed. Pet focused management relies on proper disposal of pet waste. Human E. coli loading in watershed comes from failing on-site sewage facilities (OSSFs) and malfunctions in wastewater conveyance systems. To address these issues, replacing failing OSSFs and routine wastewater line inspections were recommended. Education outreach and delivery to raise awareness about water quality and how local actions affect the watershed is also recommended. This plan outlines recommended strategies that will reduce potential pollutant loading to the Navasota River and its tributaries when implemented. However, watershed conditions change over time. To account for this, the WPP is a living document that will evolve as needed through an adaptive management process. Ultimately, the Navasota River Watershed Protection Plan sets forth an approach to improve watershed resource stewardship that allows watershed stakeholders to continue relying on the watershed as their livelihood while also helping to restore the quality of its water resources

Carters Creek Total Maximum Daily Load Implementation Project: Routine, Reconnaissance and Stormwater Monitoring Report: Tasks 4 and 5

The Carters Creek watershed is a tributary of the Navasota River and covers an area of about 56.9 square miles in Brazos County. Approximately 57% of this area is urbanized (Figure 1), primarily by the cities of Bryan and College Station. Within the Carters Creek watershed, Carters Creek, Burton Creek and Country Club Branch are all considered impaired due to elevated levels of Escherichia coli (E. coli). The Texas Commission on Environmental Quality (TCEQ) denotes these waterbodies as segments 1209C, 1209L and 1209D respectively. These waterbodies were listed on the TCEQ’s 303(d) list for bacterial impairments starting in 1999 for Carters Creek and 2006 for Burton Creek and Country Club Branch (TCEQ 2012). Each of these waterbodies was listed impaired for not meeting the E. coli standard for Primary Contact Recreation which is a geometric mean of 126 colony forming units (CFU)/100 mL of water. Initial listing of these waterbodies was supported by monitoring conducted by TCEQ and the Brazos River Authority (BRA). In 2014, a Total Maximum Daily Load (TMDL) was completed for each creek and as a result, they are proposed for delisting in the 2014 Texas Integrated Report (TCEQ 2014).Texas Commission on Environmental Quality: Award: 582-13-3005

Carters Creek Total Maximum Daily Load Implementation Project Final Report

The “Carters Creek Total Maximum Daily Load Implementation” project was developed to provide additional information to watershed stakeholders regarding the spatial and temporal distribution of E. coli concentrations in water across the watershed to aid in planning future implementation efforts across the watershed. This goal was accomplished through a variety of focused tasks that collected water quality data and E. coli source information from across the watershed. Water quality monitoring was greatly expanded by utilizing four different monitoring approaches. Routine monthly monitoring conducted at four stations over a two-year period provided additional data for future water body assessments. Reconnaissance monitoring was conducted by volunteers on a monthly basis at 10 locations and provided water quality information in many areas of the watershed that had not been previously monitored. Stormwater sampling was conducted at two locations and demonstrated the influences of runoff events on water quality. Lastly, an intensive water quality monitoring approach was utilized to collect a large number of samples within selected creek segments on the same day to illustrate changes in water quality from upstream to downstream. This approach enabled specific areas of the watershed to be identified where E. coli loading is likely to occur.Texas Commission on Environmental Quality: Award: 582-13-3005

Not a Waste: Wastewater Surveillance to Enhance Public Health

Domestic wastewater, when collected and evaluated appropriately, can provide valuable health-related information for a community. As a relatively unbiased and non-invasive approach, wastewater surveillance may complement current practices towards mitigating risks and protecting population health. Spurred by the COVID-19 pandemic, wastewater programs are now widely implemented to monitor viral infection trends in sewersheds and inform public health decision-making. This review summarizes recent developments in wastewater-based epidemiology for detecting and monitoring communicable infectious diseases, dissemination of antimicrobial resistance, and illicit drug consumption. Wastewater surveillance, a quickly advancing Frontier in environmental science, is becoming a new tool to enhance public health, improve disease prevention, and respond to future epidemics and pandemics

Wastewater Analysis of Mpox Virus in a City With Low Prevalence of Mpox Disease: an Environmental Surveillance Study

BACKGROUND: Tracking infectious diseases at the community level is challenging due to asymptomatic infections and the logistical complexities of mass surveillance. Wastewater surveillance has emerged as a valuable tool for monitoring infectious disease agents including SARS-CoV-2 and Mpox virus. However, detecting the Mpox virus in wastewater is particularly challenging due to its relatively low prevalence in the community. In this study, we aim to characterize three molecular assays for detecting and tracking the Mpox virus in wastewater from El Paso, Texas, during February and March 2023. METHODS: In this study, a combined approach utilizing three real-time PCR assays targeting the C22L, F3L, and F8L genes and sequencing was employed to detect and track the Mpox virus in wastewater samples. The samples were collected from four sewersheds in the City of El Paso, Texas, during February and March 2023. Wastewater data was compared with reported clinical case data in the city. FINDINGS: Mpox virus DNA was detected in wastewater from all the four sewersheds, whereas only one Mpox case was reported during the sampling period. Positive signals were still observed in multiple sewersheds after the Mpox case was identified. Higher viral concentrations were found in the pellet than in the supernatant of wastewater. Notably, an increasing trend in viral concentration was observed approximately 1-2 weeks before the reporting of the Mpox case. Further sequencing and epidemiological analysis provided supporting evidence for unreported Mpox infections in the city. INTERPRETATION: Our analysis suggests that the Mpox cases in the community is underestimated. The findings emphasize the value of wastewater surveillance as a public health tool for monitoring infectious diseases even in low-prevalence areas, and the need for heightened vigilance to mitigate the spread of Mpox disease for safeguarding global health. FUNDING: Center of Infectious Diseases at UTHealth, the University of Texas System, and the Texas Epidemic Public Health Institute. The content of this paper is solely the responsibility of the authors and does not necessarily represent the official views of these funding organizations

Wastewater Sequencing Reveals Community and Variant Dynamics of the Collective Human Virome

Wastewater is a discarded human by-product, but its analysis may help us understand the health of populations. Epidemiologists first analyzed wastewater to track outbreaks of poliovirus decades ago, but so-called wastewater-based epidemiology was reinvigorated to monitor SARS-CoV-2 levels while bypassing the difficulties and pit falls of individual testing. Current approaches overlook the activity of most human viruses and preclude a deeper understanding of human virome community dynamics. Here, we conduct a comprehensive sequencing-based analysis of 363 longitudinal wastewater samples from ten distinct sites in two major cities. Critical to detection is the use of a viral probe capture set targeting thousands of viral species or variants. Over 450 distinct pathogenic viruses from 28 viral families are observed, most of which have never been detected in such samples. Sequencing reads of established pathogens and emerging viruses correlate to clinical data sets of SARS-CoV-2, influenza virus, and monkeypox viruses, outlining the public health utility of this approach. Viral communities are tightly organized by space and time. Finally, the most abundant human viruses yield sequence variant information consistent with regional spread and evolution. We reveal the viral landscape of human wastewater and its potential to improve our understanding of outbreaks, transmission, and its effects on overall population health

Evaluating Microbial Risks in Private Wells and Recreational Waters

Microbial contamination of water systems continues to be a significant public health concern. Evaluating human health risks associated with these contaminants and how communities perceive risks are imperative for protecting human health. This study estimated human health risks associated with exposure to contaminated well water after Hurricane Harvey flooding and at public beaches contaminated by human and nonhuman fecal sources. Well owner perceptions of well water safety and well stewardship practices three years after flooding were also evaluated. Concentrations of the fecal indicator bacterium, Escherichia coli, and the opportunistic pathogen, Legionella pneumophila (L. pneumophila), in well water after Hurricane Harvey were incorporated into a quantitative microbial risk assessment (QMRA) to estimate the risk of infection for exposure scenarios involving either ingestion or inhalation. Derived reference pathogen doses indicated that norovirus and Cryptosporidium posed the greatest health risk for gastrointestinal infections, as the estimated median infection risk exceeded the U.S. Environmental Protection Agency (U.S. EPA) modified daily risk threshold of 1 x 10⁻⁶. The human health risks associated with exposure to L. pneumophila also exceeded U.S. EPA risk thresholds. Private well owners who participated in the survey, regardless of education, income, or county of residence, generally perceived their well water to be safe, while well stewardship practices (well water testing and well disinfection) were not routinely completed. Lastly, QMRA was utilized to assess health risks at two recreational beaches impacted by human and non-human fecal sources. Concentrations of the microbial source tracking markers-human (HF183), dog (DogBact) and gull (Gull2)-were detected at varying concentrations, yet health risk estimates at both beaches did not exceed the U.S. EPA risk of illness threshold of 0.036. A microbial risk assessment for Texas well owners following exposure to flood-impacted wells has not been previously conducted. Evaluating well owner perceptions and well stewardship practices three years after flooding in context with estimated health risks is instrumental for risk mitigation and communication. Similarly, conducting a site-specific risk assessment characterizing human health risks at recreational beaches impacted by both human and non-human fecal sources is a targeted approach to identify pollution mitigation measures that are appropriate and effective for beach management