Search

Lewis' paper discussed the arguments presented by technical experts regarding frequency and risk-based culvert designs of hydraulic structures as well as examined the functions of expert witnesses. Lewis, however, did not provide relevant principles in culvert designs and failed to review other testimonies presented in the case.

A Cheyenne, WY, railroad whose culvert dumped water onto a residential subdivision during a freak storm on Aug 1, 1985 was found guilty of structural negligence. An Act-of-God defense was overruled by the jury. Implications to design engineers is that frequency-based methods of culvert design is not proof against negligence claims by other engineers during catastrophic events. A risk-based design is thought to have a wider assessment base and thus is more accurate in structural design evaluation. The validity of the jury's decision is questioned.

BSTRACT: Techniques of optimization and simulation are merged to select the most efficient arrangement of components for regional water resources development and management. Application is made to the Elkhorn River Basin in Nebraska. The Basin extends over 7,000 square miles and includes 184 proposed reservoirs. Structure sizes, locations and operating policies are selected for optimal plans based on economic efficiency and regional development. Results indicate that substantial savings in time and costs over conventional planning techniques are effected. Agreement between model output and agency design values was noted. [ABSTRACT FROM AUTHOR]