Freshwater Resources Management

Definitions

Adjudicate:  To pass on; to decide, settle, or decree; adjudge. As used in water rights, an adjudication is the equivalent of a "determination" and contemplates that the claims of all parties have been considered and set to rest.

Appropriative water right:  An exclusive property right, acquired under procedures provided by state law, to apply water to beneficial uses in preference to all appropriative rights of later priority.

Aquatic ecosystem:  The stream channel (surface and subsurface), lake, spring, or wetland, and water resources, biotic communities, and habitat features that occur therein.

Base flood:  The flood level that has a 1% chance of occurring in any given year (also known as the 100-year flood).

Beneficial use: Within the context of water rights, "beneficial use" is defined by state law as those activities for which water may be diverted for use. Beneficial uses vary by state but generally include commercial use, domestic use, municipal use, irrigation, and water used for stock and wildlife watering activities.

Critical flood:  The flood level which has a 0.2 % chance of occurring in any given year (also known as the 500-year flood).

Designated use: Within the context of state water quality standards, uses made of a water body for which water quality must be protected. Common designated uses are body-contact recreation, aquatic life support, public water supplies, and industrial and agricultural purposes.

Docket:  As used here, a file containing the documents associated with the legal establishment of a water right.

Doctrine of Prior Appropriation:  The principle in western water law that ascribes a preference right to the appropriator who first appropriates and beneficially uses water. Commonly described as "first in time, first in right."

Federal reserved water right: As generally used, a judicially created water right originating in the U.S. Supreme Court decision in Winters v. United States 207 U. S. 564 (1908). In essence, when the federal government reserves land, it also reserves that amount of water needed to accomplish the purpose of the reservation.

Floodplain:  Lowland and relatively flat areas adjoining inland and coastal waters, including flood-prone areas of offshore islands, and, at a minimum, areas subject to a 1% or greater chance of flooding in any given year. The extent of 100-year floods designates the "base floodplain." Similarly, the extent of 500-year floods designates the "critical action floodplain."

Floodplain values: Beneficial attributes and uses of floodplains, including wildlife habitat, groundwater recharge, hydrologic balance/buffering of flood flows, maintenance of the channel's hydraulic integrity, outdoor education, and recreation.

Hydropattern:  Spatial and temporal characteristics of water conditions (quantity, depth, and coverage) in a specified geographic region.

Instream flow right:  A right to a fixed or minimum flow amount, or a defined flow regime for in-situ purposes such as fish habitat protection. Generally, these rights are held by a governmental entity and purposes are delimited by statute.

Nonpoint source pollution: Water pollution caused by rainfall or snowmelt moving over and through the ground and carrying natural and human-made pollutants into lakes, rivers streams, wetlands, estuaries, coastal waters, and groundwater. Legally, nonpoint source pollution includes any source of water pollution that does not meet the legal definition of "point source" (defined below).

Point source pollution: Pollution discharged to waters of the United States through any discernible, confined, and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container, rolling stock, concentrated animal feeding operation, or vessel or other floating craft. This term does not include agricultural stormwater discharges and return flows from irrigated agriculture.

Property: That which belongs exclusively to one, including the right of use and enjoyment for lawful purposes.

Reasonable use:  The concept, included as part of the doctrine of riparian water right, that allows for water use if, subsequent thereto, water is delivered to other riparian users without "unreasonable" diminishment in quantity and/or quality.

Riparian water right:  A water right that is a right of private property vested exclusively in the owner of the abutting land for use only on that land.

Water quality:  Physical, chemical, radiological, microbiological, and biological characteristics of a water resource.

Water quality criteria: Elements of state water quality standards, expressed as constituent concentrations, levels, or narrative statements, representing the quality of water that supports a particular designated use.

Water quality monitoring:  Systematic evaluation of water quality specifically designed to answer management questions relative to management goals and objectives.

Water quality standards: The legally enforceable provisions of state or federal law; these standards consist of (1) a designated use or uses for the waters of the United States, (2) water quality criteria for protection of the uses, and (3) an anti-degradation policy.

Water right:  The property interest established in state statute and state and federal judicial determinations that attaches to a use of water.

Waters of the United States: For purposes of the Clean Water Act, all interstate and intrastate waters that have been, are, or could be used for any form of interstate of foreign commerce, including lakes, rivers, perennial and intermittent streams, wetlands, mudflats, sandflats, sloughs, prairie potholes, wet meadows, playa lakes, or natural ponds.

Wetland:  Generally, transitional lands between terrestrial and aquatic systems where the water table is usually at or near the surface or the land is covered by shallow water. More specific definitions related to NPS wetland inventory requirements and regulation under Section 404 of the Clean Water Act are presented below in the Aquatic Habitat Protection and Management, Wetlands Management, section.