Dry Weather I/I

I am seeking information from metering studies and such that have made estimates of dry weather I/I within combined systems. I am particularly interested in older combined collection systems that include interceptors located along rivers where backwater gates are present or in areas where high groundwater is present. If estimates are available in gallons/day/inch-mile (SI equivalent) or other useful unitized flow, they would be appreciated.

This work will likely result in seasonally varying inflows to EXTRAN and TRANSPORT models, so I hope I'm not too far out of the modeling realm to ask for this information in this forum.

Thanks,
Benjamin J. Sherman, P.E.
SHERMANBJ@cdm.com