Using examples, evaluate the economic and environmental benefits of different types of water technology What case studies could be used in this answer?

Learning Objectives To understand how water can be conserved To assess if desalination is a sustainable solution to the water shortages globally

1. Agriculture Drip Irrigation 2. Example – Ogallala Aquifer 16 wireless infrared sensors have been put in field – measure crop temperature to see if they need water. If they reach a certain temperature they turn on automatically. Also measure daily evapotanspiration rates, post them on the internet so farmers can adjust irrigation rates Grow wheat another crops that don’t need water Allow some field to return to grasslands – make money from hunting, ecotourism and ‘dude ranches’ Problem is that government gives higher subsides for crop fields rather than grassland filed, maybe needs to change

Ogallala Aquifer

2. Government Policies

4. Sustainable Settlements Bedzed Water efficient—Most rain water falling on the site is collected and reused. Appliances are chosen to be water-efficient and use recycled water when possible. Dongtan, China 2 water systems. Clean and grey water

4. Settlements – part 2 So-called dry sanitation technologies, such as that employed in the Gebers Housing Project in Sweden, can save much of this freshwater for other applications. These decentralized systems first separate urine from feaces and then safely recycle each for use as crop fertilizers

5. Education In Stigomta, Sweden, they hold an annual 'Pee Outside Day' which saves 50 percent of the water normally used to flush a toilet. 17th April in US have pee outside day, started in Atlanta in 2007

6. Domestic Usage http://www.youtube.com/watch?v=4MDLpVHY8LE

Other Methods of meeting water shortages 1970’s considered the idea of towing an iceberg from Antarctica to the Middle East 2006 Thames water considered bring them from Greenland Use transparent bottles, as 6 hours sunlight will destroy microorganisms and make it safe to drink

4. Desalinisation – Technological Fix? This is the removal of salt from water Cost lots, but as water scarcity increases many countries e.g Israel are turning to this 2 methods either filtering ( Saudi Arabia) or reverse osmosis( Israel, Spain and Australia) Have ecological impacts due to concentrated brine in the by product What else does Technology do to solve the water crisis?

Task Plan an answer to the following question Evaluate the view that reducing water demand is better than trying to increase water supply ? Examples 1. Dams – 3 gorges 2. Water transfers – China, snowy mountain 3. Restoration – Aral sea, River Kissimmee 4. WaterAid v Privatisation 5. Desalination 6. Virtual water 7. Conservation examples Structure Intro – why water problem 2. Main a. Increase supply good b. Increase supply bad c. Reduce water demand good d. Reduce water demand bad 3. Conclusion – look to the future, consider sustainability Evaluation throughout