Hi Labatt
I would approach the problem simply by trying to be in ChesapeakeCity at max flood. If I understand the following site correctly, the C & D floods east and ebbs west. Check it out at http://tidesandcurrents.noaa.gov/ports_screens/cnscreen.shtml under the current section. This site gives up to the minute data about conditions in that area.
From the table below, it looks like you might want to be in ChesapeakeCity around noon on the 8th
Chesapeake and Delaware Canal, Maryland/Delaware Current
8 May 2007
39.5333° N, 75.8167° W
2007-05-08 01:16 EDT Moonrise
2007-05-08 01:35 EDT -0.05 knots Slack, Ebb Begins
2007-05-08 05:14 EDT -2.16 knots Max Ebb
2007-05-08 05:56 EDT Sunrise
2007-05-08 08:41 EDT 0.01 knots Slack, Flood Begins
2007-05-08 10:36 EDT Moonset
2007-05-08 12:33 EDT 2.09 knots Max Flood
2007-05-08 15:42 EDT -0.08 knots Slack, Ebb Begins
2007-05-08 18:12 EDT -1.39 knots Max Ebb
2007-05-08 20:03 EDT Sunset
2007-05-08 20:32 EDT 0.07 knots Slack, Flood Begins
You can change the date and get other tide information for Reedy Pt at the eastern end and Old Town Wharf at the western end at;
Site Selection: U.S. Upper East Coast (Maine through Virginia)
Remember, the times of low tide and high tide do not reflect times for slack water.
Good luck
Hope I'm not steering you wrong