Memorial Day weekend is the unofficial start of the summer 2013 vacation season. This year, there is extra reason to celebrate - the Jersey Shore has rebuilt itself after the hard blow it took from Hurricane Sandy.

But there is also extra reason to be much more cautious when you enjoy the shore this summer - because the storm that knocked houses off their foundations and filled streets with sand last fall also played havoc with our waterways.

Sandy shifted the sands beneath our bays and inlets, in many cases making familiar channels shallower and more treacherous. It swept away navigational aids, and it filled our waters with submerged debris.

The seasoned captains who piloted boats through those channels over the winter say they've never seen it this bad. And summer boaters are about to experience the same thing.

In the back bays, familiar areas that were favorite places for water-skiing or tubing last year may be very different this year. Unexpected shallows or an unseen piece of debris can turn an afternoon of boating into a tragedy.

The state Department of Environmental Protection has hired contractors to scan waterways and clean submerged debris, but it would be foolish to think they've gotten it all. Sandy broke up boardwalks, houses and piers and scattered the pieces for miles. And this material moves with the tides. Even if a lagoon is free of debris today, it might not be tomorrow.

In April, Capt. David C. McAuliffe died when his Sea Tow rescue vessel sank off Great Egg Harbor Inlet, a stark and tragic reminder of the dangers inherent in boating. We don't know what caused that sinking, and we can't know, as some have suggested, whether McAuliffe might have been saved if he had been wearing a personal floatation device. But this much is true: Our coastal waters can be dangerous, and if this can happen to an experienced captain, it can certainly happen to weekend warriors who head out for a day of flounder fishing.

We also know that folks who are on vacation often cut corners where boating safety is concerned. It is all-too-common to see pleasure boats traveling at unsafe speeds, with passengers who are not wearing life jackets. And we know that mixing alcohol with boating is a bad idea, but a popular one.

If ever there were a summer to be extra cautious on the water - to slow down, to lay off the beer and to wear life jackets - this is it.

Our summer boaters are important to us. They're a big part of our economy and a big part of what makes summer at the shore so special. Let's all try to keep it that way.