1. Social – The effects on people/ society/ communities Economic – Concerns; money/ industry/ jobs/ investment/ local and national economy Environmental – Involves effect on landscape, environment, wildlife,

2. Look at the photos you have been given They show some advantages and disadvantages of the Colorado River Use the pictures to create a mind map of the ad/dis. Split your mind map into different sections of Social/ economic and environmental factors.

3. Social/ Economic/ Environmental factors Fresh water supply all year round Social 20 dams pump water to 25 m people living in American desert Migration of people in these cities due to high standard of life, climate and new jobs in area Opportunity for recreation and tourism. Lake Mead attracts over 7m visitors per year Abandoned settlements along areas flooded by reservoirs. Loss of Native American religious sites Demand for services, increase in traffic jams and air pollution in major cities due to increasing population Competition for housing increases prices Economi c Dams produce cheap HEP Industrial expansion/ mining HEP from dams power modern factories, high value electronics and computer companies in silicon valley Increase in agriculture output. Imperial valley is largest area of irrigated farmland in Western Hemisphere Tourism creates jobs, boosts local economy Hoover dam 700,000 visitors per year Huge cost of building dams has left massive debts to be repaid Running costs and maintenance high Cost of salination at $113m per year Increased cost of irrigation Environmental Creates habitats for wildlife Flood control provides settlements with security HEP is clean and renewable Salinity Reduces crop yields Corrosion of turbines in HEP plants Silting Loss storage capacity, safety problems, flood risk, greater pollution Wildlife Salmon no longer reach breeding grounds,