Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

[mgmidget72]

Hi All,

After many years planning and getting permits, I?m finally ready to start construction on my dock. The configuration is just a typical fixed pier, aluminum ramp, and a float.

The float will be in very shallow water, so the Army Corps of Engineers requires that it be supported a minimum of 18? off the bottom. The bottom slopes a bit too, so if there?s 18? below the float on the side towards shore, there will be a bit more on the outside. Construction wise, this is easy to comply with ? two additional pilings under the outside edge of the float with stringers in between. Where I?m concerned is how to best tie up my boat (18? Sea Ray bowrider o/b). As the tide goes down, the float will rest on the stringers, but the boat will continue to drop until it rests on the bottom.

From what I?ve heard, this is a fairly common requirement that the ACOE imposes in any shallow water, so I?m hoping some solutions have been developed. Does anyone have experience with a float meeting these ACOE requirements? How do you secure your boat?

Thanks,
Scott

 

[coastalrichard]

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

We have similar issues as our tides fluctuate more than two feet at times. Most folks put ample fendering on the dock itself rather than attaching to the boat and tie off loosely to allow for the drop. Good Luck

 

[emoney]

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

They make and sell dock "balls" (that's what I call them), that you feed your line through, say 7 or 8 of them. Form a loop, with the line through the balls, and put that over your dock piling. This will allow your boat to rise and fall with the dock And keep it the same distance from the dock. I've seen people just go buy larger diameter rubber balls and drill a hole through the center big enough to allow whatever size dock line they're using. Now, the work comes in the design of the dock, however, for these to help you. The idea calls for there to be free-standing posts above the water to loop this over. I'm sure you could tie your system into the bottom of these posts?

So how much deeper will the boat drop at the absolute lowest of low tides? This is the point you need to allow for, not the "normal low tide" or an average. I learned this the hard way as I tied my first sailboat snug to 4 pilings at high tide, to come back and find it "suspended" by nothing but the lines, lol. Luckily, the dock lines were new and the sailboat wasn't that heavy. Decided it was time to see what my experienced neighbors were doing after that, lol.

 

[mgmidget72]

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

Thanks for the suggestions. Hadn't thought about it that way before, but I guess it's not very different from tying off to a fixed pier with a smaller tide fluctuation.

emoney- I like the idea of tying off to the piling with the balls on a loop, but my pilings are at the land side of my float. Here's a picture similar to what I'll be doing.


Great point about allowing for lowest of low tides. Where I am though, the boat will probably be on the bottom at a regular low tide. Once it's on the bottom, it can't go any lower. My guess is that, as the tide goes out, the boat will continue to drop maybe another foot before it hits the bottom after the dock stops dropping and is supported by the stringers.

Any thoughts on mooring whips and leaving the spring lines a little looser?

Thanks,
Scott

 

[Home Cookin']

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

I moor a number of boats to various configurations in tidal water. Your best advice will come from experienced people near your house.

First question concerns the bottom--is there any harm in your boat sitting on bottom at low tide? It's not an issue for a mud/sand bottom. Might be for rocks.

It sounds like you want to tie your boat directly to, and up against, the floating dock.I know lots of people do that, but I believe the better practice is not to have the boat touching the dock or pilings (including bumpers). First, there's the rubbing/bumping from wave action. Then there's more risk of the boat getting caught or hung up when something goes awry. Yours presents another issue, that of a pier that is floating at times and stationary at times.

Sink a couple pilings away from the dock and make yourself a slip. Use them to keep the boat off the dock--there are many ways and they include pulleys, spring lines, weights or "wires." Consider placing the slip on the protected/downwind side of the floating dock, so the boat is protected, takes waves/wakes straight on instead of broadside, and can be moored correctly bow out. You will be glad to have those pilings.

 

[mgmidget72]

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

Home Cookin',

Thanks for your reply. Fortunately, the bottom is completely mud. It is a very protected estuary/salt marsh also, so not much wave action. On the downside, this also means it's a very narrow creek. Great suggestion about making a slip. I'd love to go that route, but the creek width limits me to just the float and the boat, both parallel to the creek. Anything more would really block access from upstream.

-Scott

 

[JoLin]

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

It sounds like you want to tie your boat directly to, and up against, the floating dock.I know lots of people do that, but I believe the better practice is not to have the boat touching the dock or pilings (including bumpers). First, there's the rubbing/bumping from wave action. Then there's more risk of the boat getting caught or hung up when something goes awry. Yours presents another issue, that of a pier that is floating at times and stationary at times.

I agree with this. If you can't sink any additional pilings, I'd strongly consider mooring whips. I've used them on 3 different boats, including the one in my sig) before I started docking in a slip. They held strong through all kinds of storms and Hurricane Irene last fall. They'll definitely hold the boat off the dock.

If you buy them, PAY ATTENTION to the installation instructions, particlularly the bit about placing the bases precisely the same distance apart as your bow and stern cleats. I've seen them not work when the owner just installed them any which way.

My .02

 

[mgmidget72]

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

JoLin,

Thanks for the confirmation about mooring whips. That's the solution I was leaning towards, but wasn't sure if it was appropriate for my situation or not. I guess if they can hold your Four Winns 278 off the dock in a hurricane, they can deal with my 2,000lb boat dropping a foot relative to the dock.

Thanks,
Scott

 

[oldjeep]

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

JoLin,

Thanks for the confirmation about mooring whips. That's the solution I was leaning towards, but wasn't sure if it was appropriate for my situation or not. I guess if they can hold your Four Winns 278 off the dock in a hurricane, they can deal with my 2,000lb boat dropping a foot relative to the dock.

Thanks,
Scott

2000lb boat? Why not consider a floating drive on?

http://www.jetdock.com/
http://www.jetdock.com/boat-lifts/

 

[Home Cookin']

Re: Dock Owners - Help With Securing Boat to Dock, Espically in Shallow Water

JoLin,

Thanks for the confirmation about mooring whips. That's the solution I was leaning towards, but wasn't sure if it was appropriate for my situation or not. I guess if they can hold your Four Winns 278 off the dock in a hurricane, they can deal with my 2,000lb boat dropping a foot relative to the dock.

Thanks,
Scott

despite Jolin's experience--and he is an experienced boater--I don't think I'd rely on them for storm conditions or constant wave action. But that's all academic; you'd put a small boat on the trailer for a storm. At least you can relax if you get a sudden blow.