Fish Screen Research
* How can we efficiently and cost effectively maintain fish screens to ensure resource agency criteria will be met so that water deliveries will continue, uninterrupted, to serve the needs of communities?
Need and Benefit
Resource agencies require that certain fish criteria be met in order to ensure water deliveries will continue without interruption. The implementation of effective screening is dependent on many conditions, both general and site-specific. General conditions include both hydraulics (i.e., screen approach flow and velocity distributions) and target species characteristics--both of which require specific criteria for the species targeted in a particular screening application. In addition, debris can hamper water delivery operations as well as efforts at fish protection.
Screen configurations that are the most effective in accomplishing the fish exclusion objective while at the same time handling common debris types and quantities with minimal impact to fish will be investigated to ensure that water delivery targets will continue to be met without interruption and with minimal cost to stakeholders.
Investigations will include:
* Developing methods to clean positive barrier fish screens by using hydraulics as a means for self-cleaning--different ratios of sweeping to approach velocities will be investigated
* Conducting tests on a low maintenance, inexpensive mechanical cleaning device that uses rotating fingers (similar to a traveling water screen) for removing large debris
* Investigating the effectiveness of a high efficiency cylindrical screen using tilted-wire technology
The following documents were not reviewed. Statements made in these documents are those of the authors. The findings have not been verified.
Hyraulically Cleaning Positive Barrier Screens (final, PDF,
By Leslie Hanna
Report completed on October 01, 2004