Glossary

Aquifer: An underground bed of saturated sediment or rock that yields significant quantities of water. A confined aquifer has impermeable or nearly impermeable layers, formed of silts, clays, or shales, above the water-bearing strata. An unconfined aquifer is one that is close to the surface, in which the water table rises and falls freely with infiltration of rainwater. Also called a “water table aquifer.”

Branch: A smaller stream that flows into (“branches” off from) a larger one.

Catchment: The smallest watershed area, usually defined as the area that drains an individual site, such as a school or small neighborhood, to its first intersection with a stream.

Drainage basin: A large watershed encompassing the watersheds of many smaller rivers and streams and draining to a major river, estuary, or lake.

Ecosystem: A community of living organisms and their interrelated physical and chemical environment; also, a land area within a climate.

Evapotranspiration: The return of moisture to the atmosphere by the evaporation of water from the surface and by transpiration from vegetation.

Fecal coliform bacteria: A group of bacteria which are used as indicators of possible sewage or waste contamination because they are commonly found in human and animal feces.

Floodplain: The land areas adjacent to a river or stream that are flooded during storm events.

Groundwater: Water found in spaces between sediment particles underground (located in the zone of saturation).

Headwaters: The small streams from which a creek or river “rises” or begins.

Hydrologic cycle: Also known as the water cycle, this refers to the paths that water takes in its various states – vapor, liquid, and solid – as it moves throughout Earth’s systems (oceans, atmosphere, groundwater, streams, etc.)

Impaired waterways: Stream segments or lakes that do not meet the water quality standards set for them by federal and state agencies.

Impervious surface coverage: Surfaces that do not allow stormwater runoff (rainwater and snow melt) to seep into the ground, such as sidewalks, roadways, driveways, and rooftops.

Integrated pest management (IPM): A system of reducing pest problems using environmental information along with variable pest control methods. These methods include physical, mechanical, biological, cultural, and chemical means of controlling pests.

Macroinvertebrates: Animals that lack backbones (invertebrates) and are large enough to be seen with the naked eye (macro.) Includes insects, crustaceans (such as crayfish), mollusks (clams, mussels, and snails), and worms. They are good indicators of water quality because the most sensitive can only survive in areas of high water quality.

Marl: A clay–sand soil with a high percentage of the mineral glauconite, which sometimes gives it a green color. Useful as a soil enricher when mixed into less fertile soils.

Nonpoint source pollution: Widespread overland runoff containing pollutants. The contamination does not originate from one specific location but is pollution discharged over a broad land area. Water pollution that cannot be traced to a specific source.

Outcrop: The area where an aquifer is present at or near the land surface – where it “crops out.”

Pesticides: Chemical compounds designed to control and kill pests. The term pesticides includes herbicides (chemicals to kill weeds), insecticides (chemicals to kill insects), and fungicides (chemicals to kill fungus).

Physiography: The study of a location in relation to its underlying geology.

Point source pollution: Pollutants discharged from an identifiable point, including pipes, ditches, channels, sewers, tunnels, and containers of various types.

Run: A smaller stream that flows into (“runs” to) a larger one.

Saturated zone: The underground area in which water is held in the pores and spaces within the sediments or rock. Sediments in southern New Jersey aquifers are made up of sand, silt, clay, and gravel particles. The water within the saturated zone is groundwater.

Sedimentation: The settling of soil particles (sediment) to the bottom of a waterway.

Sewage: The waste and wastewater produced by residential and commercial sources and discharged into sewers or septic systems.

Stormwater runoff: Precipitation that flows overland to surface streams, rivers, and lakes, either directly or through storm sewers.

Sub-watershed: The land area draining to the point where two smaller streams combine together to form a larger, single stream.

Transpiration: The process by which water that is absorbed through plant roots is returned to the atmosphere from the leaves.

Tributary: A stream or river flowing into a larger stream or river.

Water cycle: See Hydrologic cycle.

Water table: The top of the saturated zone (see definition) in an unconfined aquifer (see definition under “aquifer”).