Gaining streams receive water from the groundwater supply, whereas losing streams give water to the groundwater supply.
Gaining streams receive water from rain, lakes, and glaciers, whereas losing streams lose water to rain, lakes, and glaciers.
Gaining streams fill up with runoff and groundwater infiltration, whereas losing streams lose water to runoff into the oceans.
a layer or stratum in which groundwater flows downward to the water table
the porous, permeable, saturated cone of depression in an aquitard
an unsaturated, losing stream bed or stratum below a spring
The water available to recharge the aquifer is more than the amount being withdrawn, creating an imbalance, if indeed recharge actually occurs.
The water in the wells dries up because of excessive rainfall.
The water in an aquifer is confined to a particular layer and cannot be tapped by digging a well.
best—lakes and streams with easily flowing water; worst—confined aquifers composed of sandstone
best—sandstone with low hydraulic conductivity; worst—extremely permeable aquifers (such as highly fractured granite)
best—extremely permeable aquifers (such as a cave); worst—sandstone with low hydraulic conductivity
thermoelectric (hydropower) and mining
irrigation and mining
irrigation and public supply
at or below the water table
at Earth’s surface
on the sides of mountains
Water suddenly boils in disconnected voids and cracks above the water table, causing the aquifer to explosively fragment.
Water slowly boils in a network of vertical cracks above the
water table, sending up a plume of steam and hot water.
Water below the water table slowly boils in a vertical crack or natural conduit, causing a plume of condensed water vapor to rise above the vent.
well-sorted, coarse gravel
limestone with solution channels and caverns
inverted cone head
integrated saturation impulse
seepage affluence factor
the unsaturated zone below the water table where both air and water occupy pore space
a water table that sits on top of an impermeable aquitard
the unsaturated zone above the water table where both air and water occupy pore space
perched water table
Any salty water in the aquifer will rise if the water table is lowered by pumping.
The water table must be 40 feet above sea level to keep the salty water in the aquifer below sea level.
Wells drilled below sea level will produce only saline water.
The aquifer opens out into a valley in springs.
The aquifer is overlain by sandstone or gravel.
Water flows into the aquifer on one end and is trapped by aquitards above and below.
Mexico City, San Joaquin Valley in California, New Orleans, and Texas
Las Vegas, Denver, Florida, Houston
Colorado, New Orleans, San Joaquin Valley in California, and Mexico City