Acute (pollution inputs). Episodic or randomly occurring inputs of pollution to a water body. Examples include stormwater runoff that only enters a receiving water during storm events, but may have long-lasting impacts to the system.
Ambient monitoring. All forms of monitoring conducted beyond the immediate influence of a discharge pipe or injection well and may include sampling of sediments and living resources.
Assessment. The translation of scientific data into policy-relevant information that is suitable for supporting decision-making and action.
Benthic macroinvertebrates or benthos. Organisms attached to or resting on the bottom or living in the bottom sediments of a water body.
Bioaccumulation. The net uptake of a material by an organism from food, water, and/or respiration that results in elevated internal concentrations and the progressive increase of the bodily content of a toxic compound. This occurs as organisms feed on each other and concentrate the toxic compound as it moves up the food chain.
Biological monitoring (or biomonitoring). The use of a biological entity as a detector and its response as a measure to determine environmental conditions. Toxicity tests and biological surveys are common biomonitoring methods
Biological parameters. Include measures related to the plant and animal life of the water body, such as fish species diversity and abundance, or the presence or absence of indicator fishes, aquatic invertebrates, or aquatic plants.
Calibration. To adjust a measuring instrument so that it correctly reads a known standard.
Chain-of-custody. A method of tracking collection and analysis procedures, including each person who handles a sample.
Chemical parameters. Include contaminants such as metals, dissolved nutrients, oils, and pesticides, and also include chemical properties of the aquatic system such as dissolved oxygen, chemical oxygen demand, and acid neutralizing capacity.
Chronic (pollution inputs). Pollution inputs marked by long durations and frequent recurrence. Examples include continuous municipal or industrial wastewater discharges.
Compliance monitoring. A type of monitoring done to ensure the meeting of immediate statutory requirements, the control of long-term water quality, the quality of receiving waters as determined by testing effluents, or the maintenance of standards during and after construction of a project (modified from Resh, D. M., and Rosenberg, V.H., eds., 1993, Freshwater Biomonitoring and Benthic Macroinvertebrates: New York, Chapman and Hall, 488 p).
Composition. In watershed monitoring, the types of organisms collected.
Data Quality Objectives (DQOs). In the context of water quality monitoring, the characteristics or goals that are determined by a monitoring or interpretive program to be essential to the usefulness of the data. They would include, but not be limited to, the specification of delineation of the limits of precision and bias of measurements, the completeness of sampling and measurements, the representativeness of sites relative to program objectives, the validity of data, and so forth.
Designated Use. Water use taking place within a waterbody and/or protected for continued future utilization; e.g., hydro-electric power generation, navigation, drinking water supply, fish propagation, recreation (swimming, boating, fishing, etc.).
Diversity (of aquatic species). The variety of different species detected through monitoring in a given area. Other types of diversity sometimes addressed by monitoring include genetic and habitat diversity.
Ecological conditions. The degree of functionality or health of an ecosystem, measured by a broad array of indicators of condition that include biotic characteristics (e.g., native plant communities, fish or invertebrate populations, species and habitat biodiversity) and abiotic characteristics (e.g., streambank stability and erosion, assimilation and cycling of nutrients, maintenance of sufficient flow and water temperature).
Effectiveness monitoring. Documents how well the management practices meet intended objectives. Monitoring evaluates the cause and effect relations between management activities and conditions of the riparian dependent resources. Terrestrial and instream methods constitute monitoring that evaluates and documents the total effectiveness of site-specific actions.
Environmental indicator. A measurable feature or features that provide managerially and scientifically useful evidence of environmental and ecosystem quality or reliable evidence of trends in quality.
Fixed-station monitoring. The repeated long-term sampling or measurement of parameters at representative points for the purpose of determining environmental quality characteristics and trends.
Hydrology. Dealing with the properties, distribution, and circulation of water on or below the earth's surface and in the atmosphere.
Implementation monitoring. Documents whether or not management practices were applied as designed. Project and contract administration is a part of implementation monitoring.
Meta-data summaries. Information that describes the content, quality, condition, and other characteristics of data.
Monitoring. Periodic or continuous collection of data (measured parameters) using consistent methods to determine the status (the condition of the ecological resources) of a water body and watershed and the changes in those measurements over time.
Nutrients. Elements like nitrogen and phosphorus that are essential to healthy plant life, but in excess are detrimental to water quality.
Physical parameters. Include general conditions such as temperature, flow, sediment characteristics, water color, and within-channel habitat structure.
Preservation (of field samples). Using chemicals to "fix" samples in the field so that parameter concentrations don't change en route to the lab.
Quality assurance/quality control (QA/QC). A system of procedures, checks, audits, and corrective actions to ensure that all EPA research design and performance, environmental monitoring and sampling, and other technical and reporting activities are of the highest achievable quality.
Remediation. Action taken to correct or treat a pollution problem.
Representativeness. A desirable quality for a monitoring sample site or station, which exhibits physical, chemical, and biological characteristics typical of the water body or medium being sampled.
Response indicator. An environmental indicator measured to provide evidence of the biological condition of a resource at the organism, population, community, or ecosystem level of organization.
Risk Assessment. A method for evaluating the likelihood of occurrence of an adverse effect as a result of exposure to one or more stressors.
Stage-discharge relationship. A comparison of depth of water vs. flow rate in a stream or river.
Total Maximum Daily Load (TMDL). A calculation of the maximum amount of a pollutant that a waterbody can receive and still meet water quality standards, and an allocation of that amount to the pollutant's sources. Water quality standards are set by States, Territories, and Tribes. They identify the uses for each waterbody, for example, drinking water supply, contact recreation (swimming), and aquatic life support (fishing), and the scientific criteria to support that use. A TMDL is the sum of the allowable loads of a single pollutant from all contributing point and nonpoint sources. The calculation must include a margin of safety to ensure that the waterbody can be used for the purposes the State has designated. The calculation must also account for seasonal variation in water quality. (From federal Clean Water Act)
Turbidity. A measure of water clarity. Turbidity, or cloudiness, can be caused by different sources of suspended particles in the water (e.g., suspended sediment or algae).
Validation monitoring. Determines if predictive model coefficients are adequately protecting the targeted resources. A long-term commitment to data collection is often required to establish an adequate data base. If the standard, which requires use of 50 percent or less of streamside herbaceous forage, for example, fails to achieve the desired instream habitat condition, then the standard would have to be modified for less forage consumption in the riparian complex(es).
Water quality assessment. The determination whether a water body is attaining its designated uses for such purposes as drinking, contact recreation, fisheries, and irrigation, based on state Water Quality Standards as provided for in the Clean Water Act of 1987.
Water quality monitoring. An integrated activity for evaluating the physical, chemical, and biological characteristics of water in relation to human health, ecological conditions, and designated water uses.
Water quality standards. State-adopted and EPA-approved ambient standards for water bodies, that prescribe the use of the water body and establish the water quality criteria that must be met to protect these uses. The three components of water quality standards include the beneficial designated use or uses of a water body (for example, drinking water supply, contact recreation (swimming), and aquatic life support), the numerical and narrative water-quality criteria that are necessary to protect the use or uses of that particular water body, and an antidegradation statement. (From federal Clean Water Act)
Water resource quality. The condition of water or some water-related resource as measured by biological surveys, habitat-quality assessments, chemical-specific analyses of pollutants in water bodies, and toxicity tests; or, the condition of water or some water-related resource as measured by the following: habitat quality, energy dynamics, chemical quality, hydrological regime, and biotic factors.
Watershed monitoring. Monitoring primarily designed to sample and assess the characteristics and/or condition of a watershed or watersheds, or to sample and assess specific entities on a watershed basis (i.e. as a geographic unit for sampling). For example, water quality monitoring conducted on a watershed basis would include monitoring physical, chemical, and biological condition of the water body as well as specific watershed characteristics (e.g., stream corridor traits, wetlands, and watershed land use/land cover patterns) that may be related to observed water quality.
Sample. (Statistical sampling meaning) A collection of sampling units drawn from a sampling frame.
Sampling units. (Statistical sampling meaning) A non-overlapping set of measurements that covers an entire sampling population.
Sampling frame. (Statistical sampling meaning) A list of sampling units from which a subset (sample) can be drawn.
Sampling design. (Statistical sampling meaning) All of the details concerning sampling units, sample selection, timing, spatial distribution and other issues involved in gaining sufficient sampling data for a monitoring and assessment program.
Random sampling. (Statistical sampling meaning) A sampling method in which every possible sample has the same chance of being selected.
Systematic sampling. (Statistical sampling meaning) A sampling method in which sample selection begins at a random starting point but subsequently selects additional sampling units at equal intervals along a stated gradient or numbered list; for example, sampling a river channel's width and depth at 1-kilometer intervals along its full length.
Stratified random sampling. (Statistical sampling meaning) A sampling method in which the population is separated into groups (strata) usually based on some internal similarities, then selecting a random sample within each stratum.
Sampling population. (Statistical sampling meaning) A set of measurements, about which inferences are made.
Sampling frequency. (Statistical sampling meaning) The interval, as measured in space or in time, between sampling events; often this refers to temporal frequency of repeating the same monitoring procedure.
Probability-based sampling. (Statistical sampling meaning) A sampling method in which randomness is built into the design so that properties of the sampled population can be assessed in terms of their likelihood of ocurrence or existence.
Estimation. (Statistical sampling meaning) The description of certain numerical characteristics of a population; the main method of inference used in sample surveys.
Precision. (Statistical sampling meaning) The repeatability of a measurement.
Accuracy. (Statistical sampling meaning) The closeness of a measurement to the true value of the parameter measured.
Bias. (Statistical sampling meaning) A type of survey sampling error resulting from the sample not perfectly representing the population it is drawn from.
Trends and changes. (Statistical sampling meaning) A trend is the consistent directional change in a population's characteristics documented by a minimum of three sampling events over a period of time (or sometimes distance); a change is a difference in a characteristic between just two sampling events.
Statistically significant results. (Statistical sampling meaning) Sampling data that collectively meet or exceed data quality objectives or pass a statistical testing method, and therefore can support or disprove a hypothesis or other inference.