What are some general safety guidelines regarding "Spoil Areas"

[DavidJH]

My wife and I are taking our first bareboat charter next week and there are quite a few "Spoil Areas" in the region. I am aware that this is indicative with content dumped in the area that could cause an irregular bottom. Is there a general safety rule people follow as to when it is safe to sail over? If we draw 5 feet and its denoted as 10, are we safe to sail over it?

[GordMay]

NEVER!
Deadlier than the plague, identify, highlight, and stay clear of dashed outlines with descriptions like "Spoil Area", "Fish Haven", "Fish Traps", or "Dumping Ground".
Spoil areas never show soundings, because depths change all the time.

[zeehag]

spoil areas--DO NOT sail over them. your boat will break. unless of course they are in deeeep water and depth over them is more than your draft. that part you never know until too late. best of luck.

[Shrew]

Depth could be 10 feet of water, with an 8-foot object sitting on the seabed. Depths don't typically, knowingly include man-made objects.

[Jim Cate]

You don't say where the charter area is, and that leads to lots of speculation.

Spoil areas generally refer to places where dredge spoils are dumped. This usually involves large barges with tugs or dredge ships themselves. All these vessels sport considerable draft, and would not venture into shallow water to disgorge their loads.

So, my advice would be to look at the chart and check the depths around the spoil area. If they are shallow, say your draft plus less than ten feet or so, I'd avoid. If they are deeper (as many will be), I'd not worry about them and sail confidently over their alleged hazards... as I have done many, many times.

Jim

[John_Trusty]

It's a question of Local Knowledge. I sail over "spoil areas" all the time near my home port, but I know where I am, and have sailed over them with other knowledgeable sailors for years. We all know how close to the island we can get, and where that junk car is sitting on the bottom (seriously). If you're not familiar with the area to that extent (like walking through your own back yard), then follow the excellent advice above and stay out of the areas without depth marks.

[Sailmonkey]

We’ve got spoils that are hardly more than gentle humps in the bottom, and others that are inches deep.

Problem is they’re both depicted the same way in the chart.

Local knowledge is key

[RaymondR]

Originally Posted by Jim Cate

You don't say where the charter area is, and that leads to lots of speculation.

Spoil areas generally refer to places where dredge spoils are dumped. This usually involves large barges with tugs or dredge ships themselves. All these vessels sport considerable draft, and would not venture into shallow water to disgorge their loads.

So, my advice would be to look at the chart and check the depths around the spoil area. If they are shallow, say your draft plus less than ten feet or so, I'd avoid. If they are deeper (as many will be), I'd not worry about them and sail confidently over their alleged hazards... as I have done many, many times.

Jim

Thank god for a bit of common sense Jim.

[senormechanico]

After not paying quite enough attention to the chart, I sailed over a spot near Everett WA which showed a wreck.


The fathometer read 60 feet.......13 feet.............................................. .................................................. ..........................................60 feet.


This was done when we were sailing newbs on our previous boat.
At least it had a full keel with a protected rudder!

It was still a tense situation when I realized where we were until it was over.

[billknny]

Originally Posted by GordMay

NEVER!
Deadlier than the plague, identify, highlight, and stay clear of dashed outlines with descriptions like "Spoil Area", "Fish Haven", "Fish Traps", or "Dumping Ground".
Spoil areas never show soundings, because depths change all the time.

When ever you say "Always" or "Never" about sailing you are probably wrong, and hat is one the silliest absolute statement I have read in some time. Of course you can sail over some, even the vast majority of them. Most of them have minimum depths marked. If there is a spoil area and the surrounding depth is 40 or 50 feet, are you really saying that you can't sail over it???

Attached is an example of a fish haven in the Chesapeake Bay. If you draw less than 15 feet, this is perfectly safe to sail over. I have. I sail over fish havens and artificial reefs all the time. Heck, I seek them out for the good fishing that occurs there. Some of the "fish havens" are way over 100 feet deep.

Also attached is an example of a "dotted line" Disposal Area in the middle of San Francisco Bay that EVERY sailboat in the bay sails over all the time. This is used as a disposal area for dredged material all them time. Nobody has had their bottoms ripped out.

Look at your chart. Learn what the symbols mean, and READ the notes. In places like the Chesapeake, if you really believed you had to avoid EVERY SINGLE spot marked "Fish Trap Area" you would have to stay out of 25% of the bay. What you DO have to do when you are in a "Fish trap area" is watch for crab pot buoys, (common) and (much less frequently) the stakes of a real fish trap.

[Sojourner]

I sail over fish havens all the time here in the Med at least. Most are in 20-30 m depth. Ain't no way something is sticking up that far. If it was less than 10 m I probably would go around but doubt I would need to.