Water Quality Division

Monitoring Program

OCC is responsible for monitoring, assessing, and evaluating waters of the State to determine the impacts of NPS pollution. To accomplish this goal, OCC has developed a Rotating Basin Monitoring Program to monitor the overall aquatic health of streams across the State. OCC also conducts water quality and related monitoring specific to individual education or demonstration projects. OCC follows a set of peer and EPA approved Standard Operating Procedures. OCC also collects data under EPA approved Quality Assurance Project Plans.

In general, OCC monitors water quality, stream habitat and stream aquatic communities to evaluate beneficial uses support and to identify impacts from non point sources. However, we also collect a variety of other information including landuse, soil nutrients, atmospheric deposition, and other pertinent information.

The results of this monitoring are useful in planning the focus of the NPS program, and are also used to draft the NPS Assessment Report. The data is also stored on the national water quality STORET database.

OCC also relies on the assistance of several federal and state partners to review and supplement these monitoring efforts. These partners are essential to the overall success of the State's NPS monitoring program by monitoring the larger streams and rivers, lakes and groundwater.

Water Quality

One of the most important variables to the overall aquatic health of a waterbody is its water quality. Water Quality Monitoring consists of monitoring the physical and chemical properties of water for purposes of determining whether the water is of sufficient quality to support its beneficial uses. Standard parameters that are collected during water quality monitoring include Temperature (°Celcius), Specific Conductance (µseimen), pH (standard units), Dissolved Oxygen (milligrams per liter or mg/l), Instantaneous Discharge (cubic feet per second), Alkalinity (mg/l), Turbidity (Nephelometric Turbidity Units), Total Kjeldahl Nitrogen (mg/l), Ammonia (mg/l), Nitrate (mg/l), Nitrite (mg/l), ortho-Phosphorus (mg/l), Total Phosphorus (mg/l), Total Hardness (mg/l), Sulfate (mg/l), Chloride (mg/l), Total Suspended Solids (mg/l), and Total Dissolved Solids (mg/l). Additional parameters might include concentrations of various heavy metals, pesticides, fecal bacteria, or other organic compounds. These measurements are generally collected at least once a month to characterize a stream's overall water quality.

These concentrations are compared to Water Quality Standards using a standardized protocol described in Oklahoma's Use Support Assessment Protocols to evaluate the water quality of the waterbody in question.

Stream Habitat

As important to the overall aquatic health of a system is the habitat available for aquatic organisms. Some streams have adequate water quality, but poor habitat limits the type of organisms that live in the stream. Therefore, habitat measurements are collected at least twice a year to characterize the type of habitat available. More frequent measurements may be necessary in less stable stream types. Standard parameters measured during habitat evaluations include: stream flow, channel sinuosity, distance of the measured segment, depth of water, water width, and bank width, embeddedness of the substrate (amount of sand, silt or clay deposited in rifles), substrate type (sand, silt, clay, cobble, gravel, bedrock, etc.), habitat type (riffle, pool, run), amount and type of instream cover, percent canopy cover, presence or absence of point bars, evidence of scouring or deposition, estimate of type and amount of bank vegetative cover, and average percent of bank erosion occurring along the stream segment.

Stream Aquatic Communities

Another important measure of aquatic ecosystem health is the status of its biological community. What type of organisms live there, how diverse is the community, and how healthy are the individual organisms are important indicators of the overall health of the system. OCC collects information on all stages of the food chain in streams beginning with the algal or periphyton (attached algae) community. OCC mainly concentrates on the density of the periphyton community, although sometimes we also consider what types or species of algae are dominant in the stream.

OCC also measures the type and densities of benthic macroinvertebrates (aquatic insects) that live in the stream. Certain species are indicators of poor or pristine water quality. In addition, whether or not the community is well balanced and diverse is a good indicator of pristine water quality. OCC follows Standard Operating Procedures (SOPs) based on EPA's Rapid Bioassessment Protocols (RBP) to collect and analyze this data. Benthic macroinvertebrate collections are usually made twice a year.

Finally, it is important to consider the type and health of fish that live in a stream. Once again, certain fish are more or less tolerant of pollution than others. In addition, the presence of lesions or tumors on a percentage of the population may suggest impacts of pollution in a stream. OCC collects fish at least once a year at each monitoring site to analyze according to their SOPs based on EPA's RBP.

Oklahoma's Use Support Assessment Protocol

Oklahoma's Water Quality Standards provide quantitative and qualitative measures to determine the quality of the State's waters. However, standards provide little information about how those measures are to be applied or interpreted. For instance, standards do little to specify the number of samples necessary to make decisions or how to apply qualitative or narrative criteria. Therefore, the State, through the Oklahoma Water Resources Board, developed Use Support Assessment Protocols (USAP) to describe how to apply Water Quality Standards to determine whether or not a waterbody is meeting its beneficial uses. For more information, see the Oklahoma Water Resources Board Website.

Beneficial Uses

The Oklahoma Water Resources Board assigns beneficial uses to waterbodies of the State based on what the water is used for, or what it could be used for. These beneficial uses include public and private water supply, fish and wildlife propagation, agriculture, hydropower, municipal and industrial process and cooling water, primary body contact recreation (such as swimming), secondary body contact recreation (such as boating or fishing), navigation and aesthetics. All uses receive equal protection, and waterbodies are generally assigned more than one beneficial uses.

For more information about beneficial uses, see the Oklahoma Water Resources Board webpage.