Does your WW plant have Parkson AquaGuard self-cleaning screens?  If so, does your plant have trash racks or otherwise fixed bar screens before the AquaGuard screens, in the preliminary influent channels?  We are trying to determine if trash racks are required before these screens, as they were not initially installed.

Thanks for all replies. 

I've had the Parkson screens, without any sort of a trash rack.

A key point is whether you've experienced anything that would warrant the need.  Anything unnecessary in the flow stream is asking for potential headaches.  If you've experienced anything...I'd contact the manufacturer and their rep. for suggestions.

When you think about it, you and most utilities have lift stations with smaller pumps, without any screening.