HOW WE USE WATER

Grace MasterjohnSean KlapperichAutumn KelleyAmanda Lance

HOW WE USE WATERWhere Does Our Water Go? Diverting Surface Water

Using and removing damsCosts and benefits

Dikes and leveesGroundwater

WHERE DOES OUR WATER GO?Residential/Municipal: Drinking, cooking, and

cleaningAgricultural: Irrigate crops and water for

livestock.Industrial: Manufacturing processesConsumptive use: Take thewater and don’t return it.Non-Consumptive use: We only temporarily use it.Ex: Hydroelectric dams

DIVERTING SURFACE WATERWater is diverted from rivers, streams, lakes,

and ponds to provide water for farm fields, homes and cities.

We are overexploiting surface water.Colorado River is a prime example of the

depletion of our surface water.

USING AND REMOVING DAMSA dam is an obstruction placed in a river or

stream.We build dams to prevent floods, provide

drinking water, facilitate irrigation, and generate electricity.

There are about 45,000 large dams (greater than 49 feet high) worldwide across rivers in over 140 nations.

A concept introduced in the late 1990s, removing dams restores ecosystems and fisheries, and revives recreation.

BENEFITS AND COSTS OF DAMSBENEFITS COSTS

Power generationEmissions reductionCrop irrigationDrinking waterFlood controlShippingNew recreational

opportunities

Habitat alterationFisheries declinePopulation displacementSediment captureDisruption of floodingRisk of failureLost recreational

opportunities

DIKES AND LEVEESHelp prevent floods.They are long raised mounds of earth along

the bank of rivers.Most of the time stops flooding, but can

sometimes make flooding worse because they force water to stay in channels and accumulate lots of energy, leading to occasional catastrophic overflows.

GROUNDWATERGroundwater is extracted by drilling into the

ground and using pipes to transport it.Most groundwater is beingused faster than it can replenish itself.Artesian spring: Unconfined aquifer

We have altered many environmental systems.

60% of the worlds largest 277 rivers have been affected by artificial dams, canals, and diversions.

Our consumption of fresh water is unsustainable.

We are depleting many sources of surface and groundwater.

1/3 of the world’s people have already been affected by water scarcity as of 2006.

INEFFECTIVE IRRIGATION WASTES WATER18% of the world farmland is irrigated but

yields fully 40% of worlds agricultural produce, including 60% of the global grain crop.

Only about 45% of the water we use for irrigations is actually taken up by crops.

When floods are liberally flooded with water that may evaporate accounts for about 90% of irrigation worldwide.

Can lead to waterlogging and salinization.

DEPLETING GROUND WATERMore easily depleted than surface water

because most aquifers recharge slowly.As aquifers are depleted, water tables drop.This will make groundwater more difficult

and expensive to extract.When groundwater is over-pumped then salt

water may intrude into aquifers.