Solutions to water problems

1. Solutions to water problems K. N. Schneider Aquatic Science 2011 Gooseberry Falls State Park, MN

2. When overusing freshwater, what can we do? • Law of Conservation of Matter • Desalination • Cloud Seeding Salzburg, Austria

3. Desalination • Makes seawater drinkable • While a swallow or two of salty water while swimming in the ocean or Gulf isn't bad, humans cannot survive on salt water. Salt water makes a person more thirsty and eventually would make you suffer from dehydration.

4. Desalination In nature, the sun causes water to evaporate from surface sources such as lakes, oceans, and streams. The water vapor eventually comes in contact with cooler air, where it re-condenses to form dew or rain.

5. Desalination – Reverse Osmosis Process • Most common form of desalination • Involves using high pressure to force salty water through a semi-permeable membrane. • A membrane is made from material that allows liquid, but not solids (like salt) to pass through it. • After the water has passed through the membrane, what is left is purified water and salt.

6. Desalination - Drawbacks • High cost of the energy needed to operate the plants • The safe disposal of the plant's highly concentrated salt byproduct.

7. Cloud Seeding • Texas has a lengthy history of using cloud seeding to lessen the impact of periodic, often severe, droughts. • Here is how it works • Pilots set off flairs of silver iodide in a developing thunderstorm’s updraft. • The silver iodide acts like ice crystals and attracts supercooled water droplets. • Once the droplets get too big, they start to fall and melt into rain on their way down. • The more ice crystals you have, the more rain that falls. • Video: http://www.kxan.com/dpp/news/texas/Cloud_seeding_to_make_more_rain