Water Usage Notes 1

How We Use Water Subtitle

Water Usage In order to harness water, we’ve achieved great advancements in technology and engineering 60% of the world’s largest 227 rivers are affected by dams, dikes, levees, and diversions We are also using water at an unsustainable rate Use it for households, industry, and agriculture 10% is used for municipal and residential purposes 20% is used in industry for things like mining and other manufacturing processes 70% is used in the field of agriculture whether for crops or livestock Consumptive use Removal of water from aquifers or the surface that is not replaced Irrigation is our primary consumptive use We irrigate to keep up with population demands Most irrigation is inefficient and we often overirrigate Governments often subsidize irrigation practices to promote agricultural self-sufficiency Non-consumptive use Water that is temporarily removed Example: Water for hydroelectricity

Diverting Water to Suit our Needs This is not a new concept to divert water 2011 – China was planning to pipe water from Southern China to a river in Northern China roughly 1,550 miles LA has seen multiple projects to divert water from other areas to keep up with the growing population Lester Dore – High Country News 1997

Diversions Dikes and Levees Dams and Reservoirs Long raised mounds of earth Most often used to prevent flooding However, since they often funnel large amounts of water into narrow channels, there can be catastrophic events – flooding after Hurricane Katrina was due to levee failure We often make flooding worse with pavement, concrete, and compact soil which increases runoff into rivers Dams and Reservoirs An obstruction of a river or stream to create a reservoir or artificial lake They serve many purposes Prevent floods Provide drinking water Facilitate irrigation Generate electricity 45,000 large dames have been erected worldwide with only a few major rivers remaining undammed

Dams have a mix of Benefits and Costs Three Gorges Dame in China Flooded 22 cities and forced 1.24 million people to move Submerged 10,000 year-old archaeological sites, farmland, and wild habitats Slows river flow after the dam, eroding the coastal environment

Dam Removal Some feel the cost is greater than the benefits so many dams are being removed. Migratory fish are doing better with open rivers Creates natural environment again Dams are degrading and are costly to repair However, there are issues with removing dams as well Flooding downstream Increases sediments in rivers below the dam

Depletion of Freshwater Subtitle

1989 2014 Surface Water Due to diversion and consumption, we are seeing unsustainable use Not only do rivers supply communities, but the lack of water threatens the rivers overall ecology Many major rivers barely, if at all, make it to the mouth With rivers being depleted, we are altering wetlands Efforts are being put in place to restore wetlands Lakes and seas are seeing the same issues

Groundwater Groundwater is depleted more easily Aquifers are underground water storage areas usually surrounded by rock They have recharge zones where water percolates through the ground, filling the aquifer They are often slow to recharge We are removing more than is being returned particularly in urban areas because we’ve covered the recharge zones with asphalt and concrete When water on the coasts is depleted, salt water can infiltrate This also creates unstable ground causing cities to sink or large areas to buckle and sinkholes to open up Aquifers also need to remain porous meaning loose and open If they compact, water can’t infiltrate to recharge Their overall storage capacity can decrease and not be restored Water tables need to be a certain height in order to maintain wetlands

Bottle Water Groundwater is being bottled Americans drink more bottled water than beer or milk and pay more per gallon than gasoline It’s convenient and people feel it’s safer Taste tests show no difference Labs show no real difference in safety Municipalities regulate tap water but there is next to no regulation on bottled water Also, all of the packaging is ecologically harmful Packaging creates waste Plastic is made from petroleum Costs money and fuel to transport 1,000 – 2,000 times more energy needed than for tap water 1 Liter of water requires ¼ Liter of oil and 3-5 Liters of additional water for production 3 out of every 4 bottles are thrown out instead of recycled Many manufactures move into an area, take the groundwater and leave the region degraded

Water Wars As water is depleted and climate changes, disputes over water will increase Most watersheds span various countries and territories with different needs, laws, and ideas about water use While conflicts exist, many countries have begun to work together to protect the water available

Solutions to Depletion Subtitle

Solution Shortcomings While water is a renewable resource, if we take more than a body of water can provide, the water in our area can run out We need to address supply and demand Increasing supply may be possible in some circumstances, but it can be costly and therefore, not sustainable Reducing demands seems to be the way to go long term but sill faces many challenges Political components Includes a reduction as well as conservation or efficiency efforts

Possible Solutions Desalination Removing salts from sea water or other water of marginal quality Evaporates the water and distills out fresh Force through a membrane to filter – Reverse Osmosis (RO) Many plants exist but there are many problems with them Kills aquatic life at the water intake zone Requires large amounts of fossil fuel to heat and evaporate water Creates concentrated salty waste Only wealthy, oil-rich countries really use desalination – see the weebly page for a map

Demands Agriculture Residential More efficient through crop designs such as lining canals and leveling fields Using low-pressure spray, drip irrigation, or water the soil itself Not only would efficiency conserve water, it would increase income for farmers Selective breeding and GMOs can make crops more efficient and drought tolerant Eating less meat lowers the need to grow even more crops for feed Residential Efficient showers, toilets, and washing machines Catching rain runoff from roof to water yard and garden if allowed – Why wouldn’t it be? Jot down some reasons at the end of your notes Water lawns at night or use plants that don’t require much water Municipalities and industries can do similar things while making sure structures are up to code and running efficiently as well as use recycled water for noncrucial tasks