Aquifer

An underground layer of permeable rock or soil that stores and transmits groundwater.

Permeable

A material that allows water to pass through it

Impermeable

A material that does not allow water to pass through it

Porous

Having tiny spaces or pores that can hold water.

Pervious

Allowing water to flow through it easily; similar to permeable.

Artesian Basin-

A large underground basin where water is trapped between impermeable rock layers under pressure.

Well

A hole dug or drilled into the ground to obtain groundwater

Artesian Well

A well where water rises naturally to the surface because it is under pressure.

Spring

A natural flow of groundwater emerging at the Earth's surface.

Source

the start of a river that comes from the highlands

Mouth

the ending of a river that goes to lake.ocean or another river

Catchment Area/Drainage Basin

the area drained by the river and its tributaries

Watershed/Divide

The high land separating one drainage basin from another.

Tributary

A smaller stream or river that flows into a larger river.

Confluence

The point where two or more rivers or streams meet.

Distributary

A branch of a river that flows away from the main channel, usually in a delta.

Perennial Stream

A stream that flows throughout the year.

Seasonal Stream-

A stream that flows only during certain seasons or after heavy rainfall

Valley

the long depression in which a river flows

Consequent stream

A stream that follows the original slope of the land surface

Bed of a river

The bottom surface over which a river flows

River bank

The sides of a river channel

Erosion

The wearing away and removal of rock and soil by moving water.

Transportation

the carrying of eroded materials as it flows from source to mouth

Deposition

The dropping or laying down of material carried by a river.

River Channel

the actual place where the water is flowing