Chapter 9 Section 1

Runoff

Water flowing downslope along Earth's surface

Hydrologic cycle

The cycle through which water in the hydrosphere moves; includes evaporation, condensation, precipitation and infiltration

Crest

The highest point water reaches during a flood

Bed load

The larger particles that roll or are pushed along the bottom of a stream bed

Solution

The method of transport for materials that are dissolved in the stream's water

Divide

A high land area that separates one watershed from another

Tributary

A stream or river that flows into a larger river

Watershed

All of the land area whose water drains into a stream system (ex/Potomac, Susquehanna)

Floodplain

An area along a river that is susceptible to being covered with water that overflows from a stream's banks

Levee

Deposited sediment that builds up and forms ridges along the bank of a river

Flood stage

If the water level reaches a point higher than the banks of the river, it is in this state

Stream load

Material that a stream carries

Suspension

Materials held up by the turbulence of a stream's moving water (sand, silt & clay)

Downstream flooding

Occurs in large areas after long, lasting intense rainfall, snow melt, or spring thaws

Upstream flooding

Occurs in small areas after short, intense rainfall

Flood

Occurs when more water pours into a stream than the banks of the stream channel can hold

Discharge

The quantity of water in a stream that passes a given point in a period of time (width x depth x velocity)