AN INVESTIGATION OF THE USE OF MOBILE LIDAR ON THE LEVEE SYSTEM OF CALIFORNIA DURING AN EMERGENCY FLOOD

The purpose of this project is to show that the Levee system will always need monitoring in an emergency situation. LiDAR will be able to assist emergency engineers in detecting boils as well as showing the contours of the terrain. LiDAR or light detecting and ranging is a tool used by surveyors to give a three-dimensional view of the terrain. Levee failure can be detected by the observance of boils. Boils are the results of leeway seepage and piping usually caused by small creatures such as sand crabs and snakes. This experiment used a water sustained box that was filled with soil from the Chowchilla bypass. Traditional plumbing was used to imitate the piping process. Through a steady-state of water, boils were created in an environmentally controlled situation. Using the Lycia 3000 it was possible to take a LiDAR scan of a boil. A comparison of experimental data is made to Twichel Island.

This project investigated the need for continuous monitoring of levee and boils during the event of a flood emergency using LiDAR (Light Detection and Ranging). This project was engendered by the April 2006 high water event around the city of Firebaugh and the Chowchilla bypass. Outdated maps led to incorrect information which might lead to incorrect decisions. LiDAR (Light Detection and Ranging) is used extensively in air and also can be used as a land-based and mobilized scanner. LiDAR not only sees the contours of the terrain but also can be used for the detection of the formation of boils on the landward side of the Levees. This project also looked at the occurrences and behaviors of boils which are the primary indicator of possible catastrophic failure to the Levee system. A boil is the result of head pressure forcing its way through sand. Piping is the avenue from which a boil is created and can cause levee failure. Levee failure can cost many millions of dollars in damage as well as loss of life. Failure to detect boils will result in possible failure of the Levee system such as witnessed in the Jones tract breech and the Fallon flood. Using LiDAR it is possible to realize boils in a timely manner.