how high should a bulkhead be above the water at the docks

On Sat, 21 May 2005 01:24:37 -0400, "E. T. Atkins" wrote:

It depends totally on where you are building the dock. In the great lakes, the water level does not fluctuate more than two inches. There are storm surges, however and these have been mapped and data compiled such that any given bulkhead should exceed the agreed upon maximun sieche, or storm surge, value. On Gulf ports along the US Gulf coast the tidal fluctuations are likewise small, usually not more than a few feet from minimum to maximum. So then, bulkheads there do not need to allow for much tidal fluctuation. Ten feet above mean high tide is usually not more than twelve feet above mean low tide. In puget Sound and on the Atlantic coast of Canada the tides can be terriffic. The Bay of Fundy in Canada, routinely has tides of 50 feet or more. The dock or bulkhead needs to be built such that it is above the highest high tide. In many cases this is such an extreme distance that floating docks are attached to the fixed ones and are equipped with ladders, ramps or stairs to allow access from one level to the other. So then, there is no one single answer to the question, and I have not even begun to touch on all the variations on this theme. The dock should be high enough to avoid being submerged at high high tide and low enough to allow access to the ship at low low tide. Great Lakes have no tides, the Gulf of Mexico has only one high and one low moderate tide per day and the Pacific and Atlantic oceans have two highs and two lows per day [generally speaking], some of wich are extreme in variation. To do the job right, you need to be specific about where you are modeling and study typical hydrological and marine engineering structures in that area.

Froggy, snipped-for-privacy@thepond.com

If you are modeling an ocean port do a Google seacrch for Tide Tables or Tide Prediction tables. Maybe that would help. Bruce

The bulkhead, being part of the ships, should be just tall enough to reach from the keel to the main deck. The quaywall, as others have stated, should be a little taller than the water level at maximum high tide plus an allowance for waves and storm surge. In my experience on the US east coast, the top of docks intended for commercial trade vessels are about 8' to 12' above mean water level, so that one needs a ladder to get up to the dock from the decks of small craft, one needs a ladder to get up from the dock to the maindeck of a freighter, one can walk slightly uphill on a gangway to reach the main deck of a destroyer, and one can walk slightly downhill on a gangway to reach the deck of a submarine. Of course all this is too specific, since only two types of ships ply the high seas - submarines and targets. Ole Bottom Gun, Gary Q

Hello,

At Port Covington (baltimore md) the top of bulkhead was around 12 feet above mean low water.

This was for the merchandise, coal, ore, and grain piers.

Roy

Shame on you... even this landlubber knows ALL submarines are BOATS, not ships!

Oh, if yer CPO ever sees this, yer gonna get keelhauled!

Watch that stuff, you know what people say abut sailors, and the Reac tion and Revelations crowd are getting themselves all het up about people with different sexual proclivities. Sheep seem to be OK in Laramie, though.

Thinking about this a little more, the foregoing is a description of "dry land", which accounts for there rarely being a grade in the roads or RRs from the surrounding land area to the surface of the dock (the major exception being Lake Superior type ore docks) Gary Q

When I was in the Navy my ship made a cruise to Alaska visiting several ports for PR purposes. The tides at Ketchikan, Sitka, Adak and Kodiak weren't much of a problem Anchorage was a different matter entirely. When we pulled in a tied up at the pier in the late afternoon our main deck was at about normal height relative to the pier - several feet higher so the brow angled up from the pier to the main deck. The tide was receding about that time. I went on liberty that evening. Upon returning to the ship I walked around the end of the warehouse next to which we were tied up. All I saw was some of the upper portion of the ship's superstructure. The brow was laying flat on the pier sticking out into midair. From the end of it a ladder let me climb down to the helo deck some 10 feet or so below. The helo deck was one level ABOVE the main deck of the ship. I'd estimate the tide high and low at around