The City of Arlington maintains a comprehensive monitoring program to protect water quality of receiving waters within the MS4 and comply with permit requirements. Water quality monitoring allows Environmental Management staff to assess the conditions of the local water resources in both the long and short term. The water quality sampling conducted by staff provides insight into watershed health and identifies potential pollution sources and problems.
Water Quality Monitoring Programs
- ARB WQ Monitoring Program - The City monitors five (5) locations throughout the City that have the highest concentrations of automotive related businesses. Sampling at each of the five sites includes testing for: oil and grease, total metals, and volatile organic compounds. ARB sites are monitored on a monthly basis.
- Clean Rivers Program Sampling (CRP) - In addition to monthly inner-city creek sampling, eight (8) of the monthly sites are part of the TCEQ's CRP. The CRP program is coordinated through the Trinity River Authority of Texas (TRA). The eight CRP sites are located on larger bodies of water. This provides a broader view of the health of the entire stormwater collection system as well as indicating the presence of any pollutants from illicit discharges upstream.
- Dry Weather Screening Program - Focuses on detecting the presence of illicit discharges, eliminating illicit connections, and assessing dry weather water quality changes. Dry weather sampling occurs when there has been no significant precipitation (less than 0.10 inches) within 72 hours to ensure flow is not from rainfall runoff. Tests and observations are made when the flow is first observed and again within 24 hours, but no sooner than four hours to increase the potential to detect illicit flows.
- Monthly Inner Creek Sampling - The purpose of monthly inner city creek sampling is to determine and/or detect the presence of illicit discharges. Currently, the city monitors thirty-two (32) sample sites. Sampling is typically conducted in dry weather conditions and as a result is part of the City's dry weather screening program. Sampling at each of the thirty-two sites includes eleven (11) water quality parameters determined to provide a good indication of the presence of illicit discharges. Parameters include: pH, dissolved oxygen, specific conductivity, air temperature, sample temperature, surfactants, chlorine, copper, phenols, ammonia, and visual observation.
- Regional Wet Weather Monitoring Characterization Program (RWWCP) - The City monitors wet weather events through a monitoring program designed to identify and investigate areas that may contribute excessive concentrations of pollutants to the MS4, and to establish baseline data on receiving streams. The City's wet weather monitoring efforts are coordinated by the North Central Texas Council of Governments (NCTCOG) NCTCOG provides all RWWCP data to the TCEQ on behalf of the participating entities. The City receives its water quality data from NCTCOG quarterly or when published.