Glossary

Baseflow

Water in a stream that comes from groundwater discharging into the surface water system.

Basin

An area of land that channels rainfall and snowmelt into a common outlet, such as a body of water or stream.

Synonyms: drainage basin, watershed, and drainage area. 

Confluence

The point where two or more rivers or streams meet and merge into a single channel. 

Discharge

The volume of water flowing through a river or stream per unit of time, typically expressed in cubic meters per second (m³/s). 

Flooding

The overflow of water onto land that is normally dry, often caused by rising water in nearby rivers, streams, or drainage. 

Freshet

A large increase in water discharged into a river during the spring months due to snow melt and sometimes rainfall. 

Geodetic Reference

A standardized coordinate system or datum used to measure and represent positions and elevations on the Earth’s surface. 

Headwater

The source or upper tributaries of a river or stream, typically located in highland or mountainous areas. 

Hydraulic model

A mathematical representation of water movement within a system (such as rivers, channels, or reservoirs) used to simulate and predict water behavior (for example, flows, water levels, and flow velocities) under various conditions. 

Hydroelectric

The generation of electricity using the energy of moving water, typically by directing water through turbines in dams or other facilities.