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Catch Basin Screen Cover

Catch Basin Inserts | End-of-Line Systems | Pollution Abatement Main Page |

Catch basin screens are the first line of defense for keeping trash and debris from entering the storm drain sytem. They are typically manufactured of galvanized steel. The operation and maintenance costs on these units is very minimal, especially if they do not need to be removed during the rainy season.

Several hundred screens were installed throughout the city and evaluated by stormwater engineers for effectiveness and reliability.


At site location 4 (installed on December 31, 2001) observations made on February 26, 2002 show that the screens successfully trapped trash and debris. Additionally, catch basin inserts were installed upstream from this outlet screen and this monitoring site was removed from the pilot study.

Key observations made from December 20-21, 2001 show that two of the four screens overflowed and that in all four screens, the 5-mm opening mesh became easily clogged by debris and trash. Other observations included that, at sites 1 and 2, the screens allowed water, trash and debris to escape from underneath the bottom of the screen.