Double Bayou Watershed Glossary

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Chlorophyll-a – a green pigment found in the chloroplasts of algae and higher plants that enables plants to make food through a process called photosynthesis. High levels of chlorophyll-a in water can mean that there is more algae in the water than usual. Too much algae in the water can make the water “cloudy” and decrease the amount of dissolved oxygen in the water, impacting the health of fish and other aquatic life.

Dissolved Oxygen (DO) – dissolved oxygen in water that is freely available for use by fish and other aquatic life. Different aquatic species need different levels of dissolved oxygen in the water in order to survive.

E. coli – a bacterium found in the intestines and feces of warm-blooded animals including humans, livestock, pets and wildlife. When E. coli is present in the environment, other disease-causing microbes (pathogens) could be present. E. coli is currently called a “fecal indicator bacteria,” meaning that if it is present in the water then it indicates that human and/or animal waste is also present.

Enterococcus – bacteria that are found in the intestines and waste of warm-blooded animals, including humans, livestock, pets and wildlife. When Enterococcus bacteria are present in the environment, other disease-causing microbes (pathogens) could be present. Enterococcus is also a fecal indicator bacteria.

EPA – Environmental Protection Agency. The EPA is the federal agency that is responsible for maintaining and regulating water quality in the nation’s waters under the Clean Water Act.

Fecal Coliform – bacteria found in the intestines and waste of warm-blooded animals, including humans, livestock, pets and wildlife. When fecal coliform bacteria are present in the environment, other disease-causing microbes (pathogens) could be present. Fecal coliform bacteria used to be the standard fecal indicator bacteria but they are not very specific.

HARC – Houston Advanced Research Center

Nonpoint Source (NPS) Pollution – pollution in water that comes from multiple sources or locations (not just one specific location) that is generally carried to a river, lake, or stream by precipitation runoff over land. Examples of nonpoint sources are agricultural lands, yards, roads, and parking lots.

Nutrients – substances that help plants and animals grow. Examples of nutrients in water include nitrogen or phosphorus compounds.

Pathogen – a disease-causing microorganism.

pH – a measurement of how acidic or basic a substance is. pH is measured on a scale of 0 to 14. If measured at 7 the substance is neutral, below 7 is acidic, and above 7 is basic. White vinegar is acidic with a pH of 2.4 while Milk of Magnesia is basic with a pH of about 10.

Point Source Pollution – pollution in water that comes from a single identifiable source, such as a pipe.

TCEQ – Texas Commission on Environmental Quality. This is the state agency that is responsible for maintaining and regulating water quality in Texas streams, lakes, and estuaries.

TMDL – Total Maximum Daily Load refers to the maximum amount of a contaminant that can be in a body of water and still be considered safe. TMDL also refers to a regulatory process that States, Territories, and authorized Tribes of the United States use to determine the maximum limits that are considered safe.

TSSWCB – Texas State Soil and Water Conservation Board

Turbidity – increased “cloudiness” of water caused by floating material, such as silt or organic matter.

WWTP – Wastewater Treatment Plant

Water Quality Criteria – the minimum or maximum limits set for substances found in water depending on the use of a water body. For example, an “aquatic life use” would require a minimum concentration of dissolved oxygen in order for fish to live. Yet, a “recreational use” for a water body does not need to focus on dissolved oxygen. Instead, “recreational use” would require the concentration of fecal indicator bacteria to be below a certain number in order for the water to be safe for human contact.

Water Quality Standards – a set of rules that tell how the water body is to be used, what criteria needs to be met in order to protect the water body, and how to prevent actions that would lessen water quality.

Watershed – an area of land that drains to a stream, river or other body of water. Watershed boundaries are determined by analyzing how a drop of rainfall will flow once it hits the land. High areas typically mark the edges of watershed boundaries.

Watershed Protection Plan (WPP) – a locally developed voluntary watershed management plan that helps to restore and protect water quality. The WPP process engages stakeholders in a collaborative and participatory approach in watershed planning.