Ch 11 Water Page 289

The water planet Water is essential for life You can go a month without food, but only days without water! Two kinds of water: Fresh Water Salt water = contains little salt = contains higher concentration salt Needed for: Drinking Agriculture

The water cycle Water is recycled and renewable!

Global Water Distribution Use pic on page 290 97% salt water 3 % fresh water 99% of this: frozen and underground 1% fresh and available above ground

Surface Water = fresh water found on the surface of earth Most cities depend on surface water for their supplies River systems = network of rivers/streams that move across the land Water sheds = area of land that drains into a river. Much of our pollution in rivers comes from the rivershed.

Ground Water = water beneath the Earth’s surface Water table = level where the rocks and soil are saturated with water (highest point of water underground) Aquifers = underground formation that has groundwater in it Porosity and Permeability = amount of spaces in the soil = ability to flow thru the soil or material Recharge Zone = area in watershed that has permeable ground in which water will fill up aquifers Wells = hole dug into ground to reach water underground