For open water paddling, flotation bags inside the storage compartments are excellent insurance. There are many kinds of sealable gear bags that serve the same purpose when you are carrying cargo. Hatches can become dislodged, and it's best not to bet your life on their always being watertight.

Old Yeller   

What Old Yeller said.

But, in defense of bungees, I used them on my WD12 and after some tweaking got them to where they were OK for paddling during a small craft advisory (3-ft waves, surfing down one wave and burying the deck up to the coaming in the next one, whitecaps, etc.). The main thing was to throw away the weatherstripping that came with the kit. That was open cell foam, great for drafts around your front door, but total junk for water.

I replaced it with a gasket that I cut from closed cell foam and got much better results.

The other thing I did was to put a tensioner on the bungee so that I could adjust the tension for maximum strength.

Good luck,

Laszlo

   Toggles have more hardware on deck as does the use of straps, but they maybe more secure. Bungee cords will stretch either by lifting the edge of the hatch or an object insid pushing on it.

One needs to consider how "tight" of a seal one want. If you make it air tight and seal the hatch in the cold morning there could be quite a bit of expansion by the hottest part of the day so a little seepage might be desirable.

Open cell foam has cells open to one another like a sponge. Closed cells are sealed air bubbles. Open cell foam will breathe and compress more than closed cell.

Many wet traveler use water proof bags to hold personnel gear dry. They possibly also provide some buoyancy depending upon how much air is trapped inside.

Another source of water in sealed storage compartment is condensation.

I picked up some EPDM weather seal from the big box store (used around windows and doors) and installed it instead of what CLC supplied.  3/16" high by 1/4" wide. Have not had a problem.  

I have been cutting strips of closed cell foam on my band saw and gluing it down with weatherstrip adhesive. I find this works great and lasts longer than other types. Also, if the bungies are tensioned properly and the hatch cover remains the same contour as the deck the leakage is nil. I use a similar tensioning setup as Laszlo.

Dan 

   Hey guys, thanks so much for all the excellent advice, especially taking along some air-tight bags for insurance on open water passages...that should be a no-brainer...but for my simple mind, it slipped! 

I came across left-over closed-cell foam from the seat kit on my kayak, so I'm going to try that in place of the weather stripping supplied by CLC. I've already installed the toggles, and I'm not as upset with the appearance of them as I thought I would be. Pretty low profile, so I can live with it.

Thanks again for all the input...

Dan C

   Update:

I lined the hatch covers with EPDM weather seal, D shape, and after a couple hours on a choppy bay this evening, taking a good amount of water over the front hatch, there was about a half a cup of water in the front hatch. I can live with that. Had I left on there what was supplied in the kit, I would've had easily a half gallon or so.

Thanks again for all the advice.

Dan