1. Why we need them and what happens when they fail.
Levees
Why we need them and what happens when they fail.

2. What is a levee?
A levee is a natural or artificial slope or wall to regulate water levels around a river or stream
Emergency levees are made from piling sandbags to contain water
Can be made by individuals to protect homes and property

3. Types of Levees Natural Levee Artificial Levee Made from Sediment
Formed by natural processes of erosion and deposition
Artificial Levee
Made from sediment or concrete
May be made from sandbags
Designed to address specific areas of concern

4. What is the purpose of a levee?
Levees are usually built to protect areas within a floodplain from flooding and to control the flow of water

5. How do natural levees fail?
Because natural levees are made of compacted sediment, as water pushes up against these barriers
Sediment becomes saturated and weakens
Levee breaks and water is allowed to flow freely

6. How do man made levees fail?
Levee breach – when a piece of the levee breaks away leaving room for water to pour through
Water spills over the top of the levee
Too much water pushes agains the levee causing cracks and leakage
You Tube Video – Katrina Levee Failure zX_Td-CMsO30AHqxPi1Dg&ved=0CCYQtwIwAQ&usg=AFQjCNEavbXEW

7. What are the consequences of levee failure?
Significant property damage
Loss of life and personal injury
Flooding of farmland and destruction of crops