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Alright, which shade of grey? ... Is this PSD?

Discussion in 'Public Safety Divers/Search and Rescue' started by BladesRobinson, Jan 18, 2008.

Can a PSD team perform the stand-by diver role on a commercial dive operation?

  1. Yes ... almost always

    0 vote(s)
    0.0%
  2. No ... nearly never

    6 vote(s)
    37.5%
  3. Sometimes ... depends on the situation

    6 vote(s)
    37.5%
  4. Not sure ... I want to read this thread further and learn more.

    4 vote(s)
    25.0%
  1. BladesRobinson

    BladesRobinson ScubaBoard Supporter ScubaBoard Supporter

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    Thank you to all those who posted comments and appreciated the dialog and thought provoking comments from my recent thread "Commercial or PSD?"

    We all have opinions and I thank each of you who shared their opinion with me and the other forum members. I think many learned and I too benefited from the dialog. That's why I figured I might try one more round of debate.

    This evening I was online reading a report at:
    http://www.emich.edu/cerns/downloads/papers/PoliceStaff/Unsorted/DEVELOPMENT%20OF%20AN%20ICE,%20SWIFTWATER-WATER%20AND%20rescue%20Dive%20Team%20for%20the%20City%20of%20Ann%20Arbor.pdf

    This is a report written as justification for a water rescue team and was used to fulfill partial requirements of Eastern Michigan University
    School of Fire Staff and Command.

    It is an interesting read and if you have time, check out the entire 47 page report. If time is short, read the snippet below and consider the subject recently debated on this forum (Commercial or PSD?).

    I post the story first and ask the tough question last...

    At 08:45, the AAFD dispatch center was advised by the Ann Arbor Police Department (AAPD) dispatch center that the Barton Dam located on the Huron River was leaking. The Barton Dam is the oldest dam is the area, built in 1929, it controls the largest man-made lake in southeast Michigan. A flood warning was sent out by the National Weather Service (NWS) to all communities below the Barton Dam on the Huron River. If the dam were to fail there are nine dams down river that could possibly be washed out. All on duty AAFD personnel were advised of the situation and the City of Ann Arbor’s Emergency Operations Plan (EOP) for possible flooding was put into effect.

    At 10:00 the decision was made to call in the ice, swiftwater and water rescue team leader and twelve addition personnel. These personnel would staff the ice, swiftwater and water rescue equipment at locations on both sides of the river below the dam.

    At 11:45 the ice, swiftwater and water rescue team leader was called to AAFD headquarters for a briefing from the City’s Emergency Manager (EM), Cathy Rich:

    “At 08:25, a water alarm had sounded in the control house of the Barton Dam.
    When the on-duty person went to investigate the alarm she found water pouring into a manway that leads under the dam. This manway is used for inspection purposes and travels from one side of the dam to the other. The leak was coming from a golf ball size hole in the dam about sixteen feet below the surface of the water. The concrete is six foot thick at this point of the wall. A commercial diving firm had been notified and was enroute to the dam so an inspection dive could be made on the Barton Lake side of the dam. The company had requested the AAFD ice, swiftwater and water rescue team stand-by during their dive.”

    At this time the AAFD does not have a certified rescue dive team in operation, however, the team leader is fully certified and was prepared to assist the company if this was approved by the City’s EM.

    At 13:20, the commercial diver was ready to enter the water to see how bad the problem was and if any temporary repair measures would work. Ice, swiftwater and water rescue team members were in position both above and below the dam. The team leader was in a ready position at the entry point where the commercial diver had begun his dive. The ready position means that the back-up diver is completely dressed and ready to go in case of trouble.

    The commercial diver found a six-foot hole on the Barton Lake side, but felt that a temporary patch could be made using sandbags and cinders. Twenty-three sandbags were pushed into the hole, and then ten more bags of cinders were poured in around the sandbags hoping to slow the leak down so the patch could be placed inside the manway. This operation took one hour and twenty-five minutes. The reason why the diver had to work this slowly was that the water flowing into the hole was creating a total water force of 751 pounds per square inch (PSI). One wrong move and the diver would have been pulled into the hole and held there by the water force. No one has survived being pulled into this type of pressure. The force of the water crushes the body and the lungs cannot inflate to get oxygen to the brain.

    Once the repair was made on the Barton Lake side the diver had to work down in the manway in full dive gear to attempt to complete the temporary patch. This was equally as dangerous. If the sandbags gave way the water would be coming into the manway at a rate of over three thousand gallons per minute (GPM). Because the diver had to work from below the hole in the wall, the pressure would be more than the diver could work against and he would be lost in the area under the dam. This procedure took about one hour. A wood and cloth plug was constructed and then lowered into the manway. A hydraulic jack was used to put reverse pressure against the remaining leaking water. A shoring system was then constructed from six inch by six-inch wood shoring material built to hold the patch in place until permanent repairs could be completed. All temporary repairs were completed and the diver was out of the water by 16:00. It was also decided that the situation was under control and all extra AAFD personnel were released from duty. While no AAFD ice, swiftwater and water rescue team members entered the water they were on stand-by for the completion of the temporary repair
    operation.

    Hmmm...

    Again I start with the disclaimer, I am NOT second guessing decisions and in the same position, I may have likely done the exact same thing.

    Using the advantage of hindsight and moving the hands of time forward, the question I pose to forum readers, can a PSD act as a stand by diver (safety diver) on commercial diving operation? (please answer in the poll above)



    Now, before anyone jumps up and down too much, I will remind them that OSHA allows...
    1910.401(b)
    Application in emergencies. An employer may deviate from the requirements of this standard to the extent necessary to prevent or minimize a situation which is likely to cause death, serious physical harm, or major environmental damage, provided that the employer:


    1910.401(b)(1)

    Notifies the Area Director, Occupational Safety and Health Administration within 48 hours of the onset of the emergency situation indicating the nature of the emergency and extent of the deviation from the prescribed regulations; and

    1910.401(b)(2)
    Upon request from the Area Director, submits such information in writing.

    Another words, on a commercial dive operation, rules CAN be violated if the reason is "justified" and the are director is notified. (Kudos to Joe LaRocha and other smart folks back in the 1970s for that forward thinking!)
     
  2. The Chad

    The Chad Instructor, Scuba

    # of Dives:
    Location: Landlocked Colorado
    479
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    Commercial or PSD I don't think I would have not wanted to be anywhere near that thing. Someone would have to have a great plan in place for it to even be considered. Just based upon what you posted I would think having a PSD go in after someone in that situation would make for 2 dead guys
     
  3. Gary D.

    Gary D. ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: I'm a Fish!
    Location: Post Falls, Idaho
    4,367
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    I have a mixed feeling on this one.

    With a big hole on the lake side and a small hole on the exit the danger of getting sucked in would not be eliminated but greatly reduced. But if a diver got sucked into it a PSD is not going to free him. The best bet would be lower the water level and recover the stuck diver.

    A stuck diver may reduce the flow enough so a patch could be applied from the man-way. Then with the flow reduced a PSD may be able to remove the body.

    The man-way should be treated like a cave dive with current and that is out of the scope of most PSD’s. Had the outside patch failed there isn’t much a PSD is going to be able to do other than recover a body once the current stabilized.

    I would allow about half of my team to be a stand-by on the lake side but ONLY if they agreed to it. The other half is not ready for an operation like this. As far as the man-way it would be a no.

    We have a leaking dam less than 2 miles from my house. Several attempts have been made to repair it to no avail. So it will remain leaking for a long, long time. The lake side of the leak has a very wide surface area which poses no threat to a diver. Makes for some nice sculptures during the winter. :wink:

    Gary D.
     
  4. mavdog

    mavdog Public Safety Diver

    # of Dives: I'm a Fish!
    Location: Western Pa
    218
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    Shouldn't the dive tender be a quallified commercial diver, with the same quallifications as the diver he is tending?

    What would one be doing downstream if there was a possibility of the dam failing? Im not that familliar with dams but this doesn't seem right. At least not manning the river.
     
  5. BladesRobinson

    BladesRobinson ScubaBoard Supporter ScubaBoard Supporter

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    FOR CLARIFICATION...
    At 10:00 the decision was made to call in the ice, swiftwater and water rescue team leader and twelve addition personnel. These personnel would staff the ice, swiftwater and water rescue equipment at locations on both sides of the river below the dam.

    I believe the intent was to have teams staged at designated points in case they were needed for a rescue response or to give reports on the severity of the incident if the dam burst.

    Regardless, I don't think this decision is one to second guess and I believe it falls outside of the scope for this discussion/reflection. For the sake of discussion, I ask that we consider the dive component of the response and not the swiftwater component.

    Thanks in advance.

    Blades
     
  6. Desert Pirate

    Desert Pirate Dive Con

    # of Dives: 200 - 499
    Location: Bingham County, Idaho.... Thats S.E.
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    Gary.. why does Teton Dam ring a bell here? :( remember that one?

    guys... Im with The Chad. I have never been in a place were I have felt I needed to step back and say this one is not for me, but I would have told the Commersial out fit that this one was there baby.

    Stand by for a rescue below the dam, I fell would be ok for a PSD. If a tethered commercial diver is under the threat of being trapped by 750psi of water, I dont see it as anything other than sacrifice to send in a PSD behind him.

    I gotta vote NEG on this one.

    Clay :coffee:
     
  7. Gary D.

    Gary D. ScubaBoard Supporter ScubaBoard Supporter

    # of Dives: I'm a Fish!
    Location: Post Falls, Idaho
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    Yes it does but I’ll bet not as well as the folks in your area do but I’m around 400 miles away. The devastation is still visible. I work with several guys that went through it. They lost property, equipment, family and friends.

    If this scenario were on a dam like the Teton it would be a no way due to it being a totally earth constructed dam. Concrete dams are a bit more predictable.

    Our leaker up here is in no danger of failing because of the leaking.

    For those that don’t know about the Teton disaster here it is: Teton Dam Failure

    Gary D.
     
  8. Chuck Tribolet

    Chuck Tribolet Loggerhead Turtle Rest in Peace

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    750 PSI does not compute. That's the pressure generated by about 1650 feet of sea water.
     
  9. BladesRobinson

    BladesRobinson ScubaBoard Supporter ScubaBoard Supporter

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    Chuck,

    I agree and I think this is a typo by the original author. I believe the author meant to say "750 pounds of pressure" which could be one PSI over 750 square inches, 2 PSI over 375 square inches, etc.

    I am not certain what the water pressure was nor do I know the size of the opening but the author was (I believe) attempting to describe "Delta P."

    Thanks for pointing this error out to the rest of the forum members. We can save the "Delta P" discussion for a later topic on this forum.

    Blades

    = = = = = = = = = = = = = = = = = = = = = = = = = = =

    GARY-Thanks for the link to the Teton Dam failure. That reminds me of the Big Thompson Flood in Colorado.
    http://pubs.usgs.gov/fs/2006/3095/pdf/FS06-3095_508.pdf

    The greatest flood disaster of 1976 occurred on June 5 when the Teton Dam in Idaho failed. The Teton Dam is located on the Teton River in the headwaters of the Snake River Basin. The dam was breached as the reservoir was filling for the first time. About 173,000 acre-ft of water drained through the dam in 2 hours and 23 minutes. The maximum discharge downstream from the dam was estimated at 2.3 million ft³/s. The flood caused 11 deaths, and damages were estimated at $400 million (Paulson and others, 1991).

    The second largest flood disaster of 1976 was the Big Thompson River flood in Colorado. The area most affected by the flood was the Big Thompson Canyon, especially the area downstream from Estes Park, Colorado. The flood was caused by a storm on July 31 through August 1, with rainfall amounts totalling as much as 12 in. in some areas (National Oceanic and Atmospheric Administration, 1976); an estimated 7.5 in. of rain fell in some areas in 1 hour. Maximum discharges on the North Fork Big Thompson and Big Thompson Rivers exceeded previously recorded maximums at several locations. Reports of an estimated 19-ft high wall of water rushed through Big Thompson Canyon destroying everything in its path. In the narrows of the canyon, stream levels rose to 14 ft above pre-flood levels and washed away 1.9 mi of highway. The flood resulted in 139 deaths and 5 missing persons, destroyed 323 homes and 96 mobile homes, and damaged many other homes. Two counties were declared Federal disaster areas, and the flood caused $39 million in damages (Paulson and others, 1991).
     
  10. dittrimd

    dittrimd Force Fin Diver ScubaBoard Supporter

    # of Dives: 200 - 499
    Location: Coventry, CT
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    I feel that if there was a PSD "team" trained and equiped to the level required to back up the commercial diver then it would be OK. (I do not know why the commercial company could not have had more divers available for this operations.) It does not sound like this is the case in this scenario. One member of a water rescue team who is a diver not sure of his qualifications but they are not a PSD trained team.

    From my comments in the other commercial vs. PSD this instance seems to indicate that there was an immediate threat to life if the dam was in this bad of shape. I am not sure how big the body of water was behind the dam but lowering the level would seem to be an immediate action to relieve the pressure on the dam. 6' of water could be a lot to lower the lake but it does seem to be the safest way to fix the dam and prevent a catastrophic failure.

    Ultimaltey it seems as if luck was the key factor here. If the commercial diver had been trapped then it is most likely the back up diver would have been unprepared to affect any type of rescue and would have perished as well.

    Blades, great topics and discussions on both threads.

    Thanks,

    Mark D.
     

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