Divers Unlimited

[Don Burke]

Sounds normal for that wind speed, but that's still diveable with a proper dive boat full of experienced divers. I did my first open-water dives in 4-foot seas - but this was overseas. I doubt any responsible dive operators here would let people out in those conditions unless they were quite comfortable with it.

I took a look at the track from my GPS and those four footers were at about two miles short of the demarcation line. I saw the squalls in front of me and spun the wheel. I had five guys I had never seen hit the water. No one said anything and I was not going to be too concerned if they did. If it was a mistake, I consider it the mistake I wished to make.

Low viz doesn't bother me much, but I'd like it better if I had an HID cannister with me. What sort of things are you trying to "find?"

I do not know how much a cannister would help you with this.

There were nine survey towers erected for construction of the CBBT. I found a digitized version of an old chart and pulled some positions off for the towers. I really doubt the bases were completely removed.

Here is a little something from AWOIS record 9342:

LNM19/72-- TUG REPORTED DUMPING 23 LARGE CONCRETE BLOCKS (23 FEET SQUARE, 2 FEET THICK) IN APPROX. LAT. 37-09.2N, LONG. 76-07.3W. 28 FEET REPORTED OVER BLOCKS. SMALL NUN BUOY, INT. ORANGE, ESTABLISHED. BLOCKS ARE REPORTED SCATTERED APPROX. 200-250 FEET NORTH AND NORTHEAST OF BUOY. (ENT 12/22/94, SJV)
FE415SS/95-- OPR-E696-HE; NOT INVESTIGATED. EVALUATOR RECOMMENDS RETAINING AS CHARTED. (UP 1/29/96, SJV)

After thirty years with little disturbance, those blocks would make an interesting ecosystem if they are still above the sand.

It is only about thirty feet of water, so bottom times could be very long. Visibility would be dreadful most of the time.

 

[Wreck]

I had five guys I had never seen hit the water. No one said anything and I was not going to be too concerned if they did. If it was a mistake, I consider it the mistake I wished to make.

I didn't mean to imply you were being irresponsible letting them dive in those conditions. Boats that do a *lot* of people tend to be more over(?) conservative since they have a lot of inexpereinced people on them and that was my frame on context although I ddn't make that clear. I do not think 4 foot seas should cancel a dive unless it's too much trouble for the boat itself.

I don't have a problem with people diving 5 foot swells it as long as they fully understand what it's going to be like coming back up on the ladder and how to keep the boat from pounding them.

I do not know how much a cannister would help you with this.

Sorry, my context was still on wreck dives and looking for small things. Any light can be handy to peek in dark recesses, the more penetrating the better (usually). For what you're doing, a light would serve few purposes.

I really doubt the bases were completely removed.

With 28 feet of clearance and close to the bridge (out of the way of general boat traffic) I would doubt they'd find it worth their time to bring up those chunks of concrete or knock them down. Was that high tide or low? These chunks are around 5x5x2 feet it sounds how high do you think they would stack them? Any idea how they constructed the towers? Also, I am assuming they meant 28 feet between the top of the blocks and the surafce, not the depth to the sand - your thoughts?

After thirty years with little disturbance, those blocks would make an interesting ecosystem if they are still above the sand.

True, I see your interest now.

It is only about thirty feet of water, so bottom times could be very long. Visibility would be dreadful most of the time.

Long bottom time would be a given but I'd plan on 40 feet since you'd probably want to stay close to the bottom, unless that 28' WAS the bottom measurement.

I'd be game to do some searching, but not without a reel. I imagine bottom currents would be stronger around the CBBT than other places. That said, I'd have to get some cave line for my reel to get any distance out of it. Would 6-10 feet of viz be average for that area or is that too optimistic? With all the rain we've had this past week, I imagine it would be worse.

I just remembered, a friend of mine is a project supervisor for Tidewater Skanska (old Tidewater Construction Corp that built the CBBT). He probably has access to any company survey docs if you can think of what to ask him for.

Let me know what you think. I'd be interested in helping, but only on Saturdays.

 

[Don Burke]

I didn't mean to imply you were being irresponsible letting them dive in those conditions. Boats that do a *lot* of people tend to be more over(?) conservative since they have a lot of inexpereinced people on them and that was my frame on context although I ddn't make that clear. I do not think 4 foot seas should cancel a dive unless it's too much trouble for the boat itself.

With people I do not know, I am pretty conservative. Some of my more harrowing experiences have been with guys who were instructors, so I do not put much stock in certification levels.

It would have been interesting. Sho Nuff is only thirty six feet long and can generate some interesting roll and pitch rates at anchor.

I don't have a problem with people diving 5 foot swells it as long as they fully understand what it's going to be like coming back up on the ladder and how to keep the boat from pounding them.

If I had ever seen these guys dive, I might have considered it. As it was, the forecast was already bogus and I was expecting a sudden issuance of a small craft advisory, which our insurance company has strong feelings about.

With 28 feet of clearance and close to the bridge (out of the way of general boat traffic) I would doubt they'd find it worth their time to bring up those chunks of concrete or knock them down. Was that high tide or low? These chunks are around 5x5x2 feet it sounds how high do you think they would stack them? Any idea how they constructed the towers? Also, I am assuming they meant 28 feet between the top of the blocks and the surafce, not the depth to the sand - your thoughts?

The blocks and the towers are two different issues. The twenty eight feet is from the top of the blocks to the charting datum, which was probably Mean Low Water at the time. That is not much different than the Mean Lower Low Water currently in use. The position is on the chart, about a mile east of buoy 24. I suspect the report may be distorted as the number twenty three shows up in both the number and size of the blocks. It sounded like sections of bridge decking when I first read it. Some blowout day I will check the construction dates on the new James River Bridge and the second Hampton Roads Bridge Tunnel. The date is all wrong for it to be parts for the CBBT.

The only thing I know about the tower construction is from the History Channel program about building the bridge. They were triangular latice works and I will guess about twenty feet on a side. There was only a brief shot of one.

Long bottom time would be a given but I'd plan on 40 feet since you'd probably want to stay close to the bottom, unless that 28' WAS the bottom measurement.

The water around the location for the blocks is charted at twenty-six to thirty five feet.

I'd be game to do some searching, but not without a reel. I imagine bottom currents would be stronger around the CBBT than other places. That said, I'd have to get some cave line for my reel to get any distance out of it. Would 6-10 feet of viz be average for that area or is that too optimistic? With all the rain we've had this past week, I imagine it would be worse.

I have to get over to I.Coopers to pick up some line. I think #36 would not be out of line for this. I may end up buying a bigger reel for this project. Six to ten inches was more of what I had in mind.

I just remembered, a friend of mine is a project supervisor for Tidewater Skanska (old Tidewater Construction Corp that built the CBBT). He probably has access to any company survey docs if you can think of what to ask him for.

The positions I have for the towers are as accurate as I can get with what I have to work with, and still are pretty pathetic. If your friend can come up with good positions, it would be great.

Let me know what you think. I'd be interested in helping, but only on Saturdays.

Saturdays would be tough since we are trying to get boat runs going for every weekend. Days that get cancelled due to low signups are a possibility.

 

[Wreck]

Don, so you captain the boat for DU? Is it your boat or do you just work on it? I was guessing the latter.

I wasn't familiar with I.Coopers. Are they a specialty shop?

I use #36 on my reel just for durability around wrecks, but the spool only holds about 250 feet of it.

To do what you're thinking of seems like you'd find a location, drop anchor, tie one end of the reel to the anchor, swim directly away as far as the reel will go, strike a bearing with a compass, and then swim in a 360, keeping the line to one side, until you overshoot the original compass bearing. Anything higher than the bottom should snag the line and draw you in towards it, which I would hope, included concrete blocks stacked more than one high.

Search patterns seem like they'd be near useless if you can't see more than 12 inches. It would be more productive running a search pattern with the boat using a depth finder and GPS.

 

[Don Burke]

Don, so you captain the boat for DU? Is it your boat or do you just work on it? I was guessing the latter.

You are correct. I have been operating the boat when we have paying passengers and I am currently the boat handyman. Tim Smith owns the boat and the shop.

I wasn't familiar with I.Coopers. Are they a specialty shop?

They serve the commercial fishermen. The shop is on South King Street very close to the Air and Space Center in Hampton.

I use #36 on my reel just for durability around wrecks, but the spool only holds about 250 feet of it.

I picked up a five pound spool of #36 for $47 this morning.

To do what you're thinking of seems like you'd find a location, drop anchor, tie one end of the reel to the anchor, swim directly away as far as the reel will go, strike a bearing with a compass, and then swim in a 360, keeping the line to one side, until you overshoot the original compass bearing. Anything higher than the bottom should snag the line and draw you in towards it, which I would hope, included concrete blocks stacked more than one high.

If I made the full circle without a snag, I would then come in about twenty feet and try again.

Search patterns seem like they'd be near useless if you can't see more than 12 inches.

I do not need to see a concrete slab to find it.

It would be more productive running a search pattern with the boat using a depth finder and GPS.

I have tried a little of that with no luck. It does not take much wave action to hide a two foot slab. I will try some more, but I do not hold out much hope for it.