aquiferA water-bearing bed of rock or sand that feeds wells. A hole dug in beach sand that fills with water from below shows a small one at work.
droughtA long dry spell that leaves a region short of water. A drought can last for months or years. It is called a creeping phenomenon because it sets in slowly.
fresh waterThe kind of water that fills rivers, ponds and wells. Less than 1 percent of Earth's water is available for people to use. The rest is salty, frozen or out of reach.
groundwaterWater stored out of sight under the land surface. About 30 percent of the world's fresh water is groundwater.
leakAn opening that lets water slowly escape. The leaks of an average household can waste more than 9,000 gallons of water a year. Worn toilet flappers and dripping faucets are common ones.
reservoirA man-made lake that stores water for dry times. Many reservoirs also make electricity. Some have floating covers to cut the water lost to evaporation.
Show all 36 terms (30 more)
Water conservation basics, continued
reuseTo make use of a thing once more, not discard it. It is not the same as recycling, which first breaks a used thing down into raw material.
runoffWater that flows off the land and does not soak in. Roofs and pavement cannot soak up water, so rain that lands on them runs off.
water conservationUsing water wisely so that less of it is wasted. Saving hot water saves energy too, because the water heater has less to do.
water footprintThe total fresh water used to make what one consumes. It counts water used out of sight, to grow food and make goods, as well as water from the tap.
water supplyThe pipes and pumps that bring water to a town. The water may come from under the ground, from lakes and rivers or, with the salt removed, from the sea.
watershedThe land that sheds its rain toward one river. It is also called a drainage basin. Everyone on land is standing in one.
Saving water at home 12
drip irrigationWatering that drips slowly at the roots of plants. Putting water right at the roots keeps evaporation low.
drought-tolerant plantA plant that can get by on very little water. A plant that tolerates drought where it grows can live there with little or no extra watering.
dual-flush toiletA toilet with a small flush and a full flush. The first practical one was designed in Australia in 1980. Its smaller flush is for liquid waste.
faucet aeratorA screw-on tip that mixes air into a faucet's stream. The stream does not splash, and less water comes through: an efficient bathroom faucet runs at 1.5 gallons a minute, down from a standard 2.2.
flow rateHow much water passes through in a set time. It is counted in gallons a minute. The figure is often printed on the head of a faucet, as in 1.0 gpm.
gray waterUsed water from sinks, showers and washing machines. It leaves out the water from toilets, so it is easier to treat and to reuse, for flushing or for watering plants.
low-flow fixtureA faucet, shower or toilet built to use less water. A standard showerhead uses 2.5 gallons of water a minute. A water-saving one uses 2 gallons or less.
rain barrelA tank set under a downspout to save rainwater. One centimeter of rain on a roof of 100 square meters can yield 1,000 liters of water.
rainwater harvestingCollecting and storing rain to use later. The rain is usually caught on a roof and led to a tank or cistern. People use it to water gardens and livestock.
sprinklerA nozzle that throws water over grass in a spray. Up to half of the water used outdoors is lost to wind, evaporation and runoff when watering is done inefficiently.
water meterA gauge that records how much water a building uses. In the United States meters count gallons or cubic feet; in most of the world, liters or cubic meters. A meter that moves while no water is on points to a leak.
xeriscapingLandscaping designed to need little or no watering. The word was coined in Denver in 1981 from the Greek xeros, dry.
Supply, reuse and shortage 12
aqueductA man-made waterway that brings water from far off. Aqueducts were built in ancient Greece and Rome and in Mexico and Peru before Columbus. The simplest is a small ditch dug in the ground.
desalinationThe removal of salt from seawater so it can be used. Like recycled wastewater, it is a rare source of water that does not depend on rain. The salty water left over is called brine.
overdraftPumping groundwater faster than nature refills it. Long overdraft can leave wells dry, especially in a drought.
potable waterWater that is safe to drink. Potable water that reaches a home through pipes is called tap water.
rechargeThe refilling of groundwater by water seeping down. Rain and melted snow that soak into the ground recharge an aquifer. Recharge is the main way water gets into one.
reclaimed waterWastewater cleaned well enough for a second use. It waters golf courses and crops and supplies factories. The United States has more than 500 facilities that recycle water.
saltwater intrusionSeawater seeping into fresh water underground. Pumping from wells near the coast lowers the fresh groundwater and lets salt water move farther inland.
snowpackBuilt-up winter snow that melts as the weather warms. As it melts it feeds streams and rivers, and gives towns downslope water for drinking and farming.
subsidenceThe slow sinking of land, as over a drained aquifer. Pumping groundwater or oil out of the ground has made the land sink by as much as 9 meters in places.
wastewaterWater after use, carrying what was washed or flushed. In everyday speech it often means sewage, the wastewater of a town.
water scarcityToo little fresh water to meet a region's needs. It can be physical, when there is simply not enough water, or economic, when a region lacks the pipes and pumps to draw on the water it has.
water tableThe depth where a dug hole begins to fill up. Below it, water fills every gap in the soil and rock. Pumping from wells can lower it.
How this list was compiled: Term list chosen for this site on 2026-10-12. Each meaning is written in our own words and was checked that day against the article on the term in the English Wikipedia (https://en.wikipedia.org/), whose text is under the Creative Commons Attribution-ShareAlike license: Water conservation, Water efficiency, Fresh water, Groundwater, Aquifer, Drought, Surface runoff, Reservoir, Drainage basin, Reuse, Water supply, Water footprint, Leak, Low-flow fixtures, Low-flush toilet, Faucet aerator, Dual flush toilet, Water metering, Drip irrigation, Irrigation sprinkler, Rainwater tank, Rainwater harvesting, Greywater, Xeriscaping, Water table, Groundwater recharge, Groundwater depletion, Subsidence, Wastewater, Reclaimed water, Desalination, Drinking water, Water scarcity, Snowpack, Aqueduct (water supply) and Saltwater intrusion. How much water homes use, leaks, faucets, toilets, showerheads, sprinklers and plants that tolerate drought were checked a second time against the WaterSense pages of the U.S. Environmental Protection Agency (https://www.epa.gov/watersense/statistics-and-facts, Statistics and Facts; https://www.epa.gov/watersense/how-we-use-water, How We Use Water; https://www.epa.gov/watersense/fix-leak-week, Fix a Leak Week; and the pages Bathroom Faucets, Residential Toilets, Showerheads and What to Plant), and reclaimed water against its Basic Information about Water Reuse (https://www.epa.gov/waterreuse/basic-information-about-water-reuse). Aquifers, the water table, groundwater, recharge, overdraft, subsidence, watersheds and flow rates were checked against the Water Science School of the U.S. Geological Survey (https://www.usgs.gov/special-topics/water-science-school): Aquifers and Groundwater, Groundwater Storage and the Water Cycle, Groundwater Decline and Depletion, Land Subsidence, Watersheds and Drainage Basins, and Water Q&A: How much water do I use at home each day? Drought was checked against Drought Basics of the National Integrated Drought Information System (https://www.drought.gov/what-is-drought/drought-basics). Two pages of the Environmental Protection Agency give the water lost to household leaks in an average home as more than 9,300 and as 9,400 gallons a year, so the list says more than 9,000. The fact after each meaning is from the same pages. Licence: own work
How it works
This water conservation vocabulary worksheet prints water conservation, fresh water, groundwater, aquifer, drought, runoff, reservoir, watershed, reuse, water supply, water footprint and leak, with their meanings in another order on the right. The answer key is the last page.
Read the full guide
Saving water at home
Set opens on Water conservation basics. The second set has low-flow fixture, faucet aerator, dual-flush toilet, water meter, drip irrigation, sprinkler, rain barrel, rainwater harvesting, gray water, xeriscaping, flow rate and drought-tolerant plant.
Supply, reuse and shortage
The third set has water table, recharge, overdraft, wastewater, subsidence, reclaimed water, desalination, potable water, water scarcity, snowpack, aqueduct and saltwater intrusion.
Fresh water is limited, and demand for it keeps growing while the supply stays the same. In a 2014 federal report, water managers in 40 of the 50 states expected shortages in some part of their state within ten years, even in average conditions.
How much water does the average person use per day?
In the United States, an average of 82 gallons a day at home, by the U.S. Geological Survey's count for 2015. An average family uses more than 300 gallons a day, about 70 percent of it indoors.
What uses the most water in a house?
The toilet. It accounts for nearly 30 percent of the water an average home uses indoors. Showers take nearly 17 percent.
What are some ways to conserve water at home?
By the U.S. Environmental Protection Agency's figures, turning off the tap while brushing teeth saves 8 gallons a day, an efficient showerhead saves a family 2,700 gallons a year, and running the dishwasher only when full saves nearly 320.