A canoe anytime of the year is touch, but doable in higher water levels. Don't attempt it any time soon. A kayak, on the other hand, will fair much better. But its a tough stretch regardless, with lots of lift-overs and what not.
Thanks to our beloved member, "turtle", I have found that the lock was built 220 years ago this month. The construction of the lock, then, would have taken place under Henry Drinker. This information was gotten from the Wharton Ledgers.
Or rather the 1700's (namely 1765), if John Pearce is correct. See Heart of the Pines, pg. 30. Unfortunately, Pearce does not cite a source for this information.