Surface Water and Groundwater Concepts

Stream

A body of flowing water.

Channel

The physical confine of a stream.

Drainage Basin

An area of land where precipitation collects and drains off into a common outlet.

Mouth

The point where a stream meets a larger body of water.

Headwaters

The source or beginning of a stream.

Bank

The sides of a stream.

Streambed

The bottom of a stream.

Levees

Natural or artificial embankments along the sides of a river.

Floodplains

Flat areas adjacent to a stream that are prone to flooding.

Flood

An overflow of water onto land that is normally dry.

Recurrence Interval

The average time between events of a certain size or larger.

Sheetwash

Thin layers of water that flow over the ground surface.

Runoff

Water that flows over the ground surface to streams.

Downcutting

The process of erosion that deepens a stream channel.

Headward Erosion

The process where a stream erodes backward into its source.

Tributaries

Smaller streams that flow into a larger stream.

Drainage Network

A system of interconnected streams and rivers.

Drainage Divide

A ridge that separates one drainage basin from another.

Permanent Streams

Streams that flow year-round.

Ephemeral Streams

Streams that only flow during certain times of the year.

Water Table

The upper surface of the saturated zone of groundwater.

Unsaturated Zone

The area above the water table where soil and rock are not fully saturated with water.

Saturated Zone

The area below the water table where all the pores are filled with water.

Discharge

The volume of water flowing through a stream over a given time.

Base Level

The lowest point to which a stream can erode.

Stream Gradient

The slope of a stream channel.

Braided Stream

A stream consisting of multiple interweaving channels.

Meandering Stream

A stream that follows a winding path.

Point Bar

A deposit of sediment on the inside bend of a meander.

Cut Bank

The eroded bank on the outside of a meander.

Meander

A curve or bend in a stream.

Oxbow Lake

A crescent-shaped lake formed when a meander is cut off from a stream.

Porosity

The measure of void spaces in a material.

Permeability

The ability of a material to transmit fluids.

Aquifers

Geological formations that can store and transmit water.

Aquitards

Geological formations that restrict water flow.

Perched Water Table

A localized zone of saturation above the regional water table.

Capillary Fringe

The zone above the water table where water is held by capillary forces.

Hydraulic Head

The potential energy available to drive the flow of groundwater.

Hydraulic Gradient

The change in hydraulic head per unit distance.

Darcy's Law

A formula that describes the flow of fluid through a porous medium.

Recharge

The process by which groundwater is replenished.

Discharge (Groundwater)

The process by which groundwater is removed from an aquifer.

Types of Well

Different constructions of wells used to extract groundwater.

Artesian Well

A well that taps into a confined aquifer under pressure.

Potentiometric Surface

An imaginary surface representing the level to which water would rise in a well.

Cone of Depression

A downward slope in the water table around a well caused by pumping.

Climate Change Evidence

Data and observations that indicate changes in climate patterns.

Paleocene-Eocene Thermal Maximum

A period of significant global warming studied for insights into climate change.

Consequences of Climate Change

Potential impacts on ecosystems, weather patterns, and sea levels due to climate change.

CO2 Concentration Increase

The rise in carbon dioxide levels in the atmosphere due to human activities.

Earth's Warming Evidence

Indicators that demonstrate the increase in Earth's average temperature.

Fossil Fuels and Climate

The relationship between the burning of fossil fuels and climate change.

Natural Climate Regulation

Factors that naturally influence and stabilize the Earth's climate.

Recent CO2 Increase Rate

The current rate of carbon dioxide increase compared to historical natural variations.