142. The charted channel depth at Eastport, ME, is 28 feet. You are drawing 31.5 feet and wish 2 feet clearance under the keel. What is the earliest time after 1700 (ZD +4) on 6 September 1983 that you can enter the channel?

To safely enter the channel, the required water depth is the vessel's draft plus the desired under-keel clearance, necessitating a tide height of 5.5 feet above chart datum. Consulting the tide tables for Eastport, ME, on September 6, 1983, reveals that this depth is first achieved at approximately 1915 (ZD +4).