Water A limited resource

Remember the Hydrologic Cycle? From greatswamp.org

How much water is there? Graph courtesy of apesnature.homestead.com

What can we use? Surface water – fresh water on the Earth’s surface River systems - a network of connected streams and rivers. Some of the largest and best know systems are the Amazon, Mississippi, and Nile systems. Watershed – the area of land that is drained by a river. Any pollution source in the watershed area can create water pollution in the river and other bodies of water it feeds.

Groundwater – fresh water stored beneath the Earth’s surface in sediment and rock formations. Water table Aquifer Recharge Zone

Coming Up The global water crisis and the poverty connection. How do we conserve?

Water Use Residential – amount of water used varies greatly between countries Water treatment – remove contaminants Potable – safe to drink Remove pathogens as well

Water Use Industrial Agricultural Production of electricity Production of semi-conductors and technology Waste disposal Agricultural Irrigation

Water Use Per Capita From treehugger.com

Water Management The altering of streams and rivers to make them more useful for humans Diversion – for use in residential and agricultural needs Dams and Reservoirs – for above uses plus storage, electricity generation, and flood control

Water Conservation Agriculture – losses from evaporation, runoff, and seepage. Drip irrigation Photo from Michigan State Extension Service

Water Conservation Industry Residential Recycling waste and cooling water Tax incentives Residential Technology – low-flow Water your landscaping in the evening or try xeriscaping Run only full loads of laundry and dishes Check out http://wateruseitwisely.com/100-ways-to-conserve/

Solutions to Consider Desalination Transport Water Credits

Pollution The introduction of chemical, physical, or biological agents into the water that degrade water quality and adversely affect the organisms that depend on the water. Remember unwanted and harmful? Two primary causes are industrialization and human population growth.

Sources Point-Source Pollution – pollution from a single source such as a factory, power plant, or leaky oil tanker. Nonpoint-Source Pollution – From many different sources and can be hard to identify. This is what we generally refer to as watershed pollution. Very difficult to monitor and regulate Relies on public awareness / education

Principal Water Pollutants Wastewater – water that contains waste from homes or industry. Treatment – filtration and treatment processes make the water safe enough to return to the environment. Sludge – must be treated as hazardous waste. It is generally incinerated and then the ash is buried in a secure landfill. Communities are always looking for ways to detoxify sludge so it can be used for fertilizer or building materials.

SA Water Treatment

More Pollutants Artificial Eutrophication – Normal nutrient cycle – dead plants and animals are decomposed by bacteria and fungi and provide nutrition to plant and animals. Eutrophication – decomposition uses oxygen. As O2 levels decrease, plants fill in and the water areas become marshes. Artificial Eutrophication – Detergents and fertilizers add nitrogen and phosphorous to the water which increases algal growth blocks sunlight plants and animals die increased rate of eutrophication changes

Algal Blooms / Red Tides From sciencedaily.com From wordpress.com

Still more pollutants Thermal – change in the temperature of a body of water that harms the organisms living there. . Groundwater – water from the surface bring pollutants through the soil as it infiltrates down to the ground water aquifers. Also from seepage of underground storage tanks –petroleum products and sewage.

Groundwater Danger

Monsters Inside of Me Animal Planet Video

Ocean Pollution 85% of ocean pollution comes from activites on land Oil, chemical waste, medical waste Sensitive coastal estuaries and reefs are the most sensitive to runoff pollutants Oil spills – each year, approximately 37 million gallons of oil are spilled into oceans from tanker accidents like the Exxon Valdez in 1989 200-300 million gallons runoff from roadways and other nonpoint-sources on land.

Impacts on Ecosystems Water is foundational to life. Pollution has an immediate effect if high levels of the contaminant are introduced at once. Pollution has a delayed effect if smaller amounts accumulate over time (not _____________________).

Biomagnification – accumulation of toxins at each level of the food chain.

Clean Up Clean Water Act of 1972 – goal was to “restore and maintain the chemical, physical, and biological integrity of the nation’s waters.” While the 1983 deadline was not met, major improvements have been made. The Potomac is a wonderful example Oil Pollution Act of 1990 – All oil tankers in US waters must be double-hulled by 2015.

https://www.youtube.com/watch?v=_9OGvcVA3Gw https://www.youtube.com/watch?v=QGpyD1maXqc&list=PLw4dgC6O10mcw7ymbkMpO6guR51TvafUs http://www.animalplanet.com/tv-shows/monsters-inside-me/videos/cryptosporidium-outbreak.htm http://www.nytimes.com/video/world/americas/100000001463594/cholera-grips-haiti.html