The Losers

Emmett: On an 8 lane, 8 foot deep pool, lowering the water level by .8 meters would change the load on the end wall by about 42 tons. (1.13 lbs/in^2 times the number of square inches of the wall. The loss of pressure would be subtractive for all of the wall below 0.8 meters). Of course, it depends on the construction of the pool how much the walls will move. I can imagine much more sophisticated calculations, using moments of load (or whatever it is called). We are not talking about compression of concrete, but flex. If the earth behind the wall has settled, or been washed away by rain in spots, things could move more - anyway, one should be check it out. (Is it *really* true that once a pool is built, its length does not change?) I think you're right, the walls, if they move, would bow in. Maybe the side lanes would even get shorter, as the side walls should bow in, also, pulling the end walls together, so I am not sure the differential check you suggest would work. The .8 meters, and the qualified surveyor commment, came from the FINA rules, as laid out by Wayne. I understand the USMS rules are different, though there seems to be a move toward convergence (see Wayne's latest post.) Construction of the pool could be black and white, if everyone agreed on what it meant. For example, specifying a length without a tolerance is not specifying a length at all. You will not get a civil engineer to agree that a length and tolerance specification like 25.00 (-0.00 +0.02) means that a pool can't *really* be 24.998 meters long (if you could measure it to that precision). The long established definitions of tolerances are how civil engineers avoid losing lots of legal suits. Wayne: some record of the type and thicknesses of touch pads used at each pool should be maintained also, as changing the make may change the pool length, or is it totally standardized? Is cost of establishing pool length, and who pays for it, an issue? And like Emmett, I fear we will lose lots of pools by these more stringent rules.

sometimes meets are run with pads on both ends, sometimes only on one, sometimes with none, all on the same pool. Should this be allowed, or permitted as long as the two-pad format is the proper length?

I'm going to weigh in on a comment above by M. Heather... It is true that a pool can legally be a few mm short of 25 meters if in fact the rule states the pool must be 25.00m long. As Philip has noted, the key word is "resolution." In this case the measurement of 25.00 is taken out to 2 decimal places, or 1cm. Therefore the official measurement needs to be rounded to 2 decimal places. So if the pool is 24.996 meters long (4 mm short) it would satisfy the condition of being 25.00 long as a minimum because 24.996 rounded to two decimal places is in fact 25.00 (Of course it is likely the margin of error in taking the measurement is probably far more coarse than two decimal places so this example is purely hypothetical. I simply wanted to try to explain how you can have a "shorter" pool than 25m but still satisfy the minimum length.) Any other engineers want to back me up? Jeff Roddin, P.E.

After looking at the top 10 rankings I noticed two of my times went unrecorded. After some checking, I discovered they were rejected because they were done at a meet in VA where the pool was too short. Too bad for us but rejecting the times was the right thing to do. I did a little mental math and added a little time and am personally satisfied that my real times aren't that far off. On the bright side, I think I'm number one at the 99.8 meter backstroke, 49.9 meter backstroke and still ahead of Tall Paul!

Jeff - you are correct sir - especially your remark about the coarseness of tape measurement. Now, lets take that a bit further. Steel tape introduces inherent inaccuracies (the measurement will ALWAYS be longer than the actual pool length) due to problems cited by others in actually getting the tape straight (tape sag due to no flat surface to lay it on). When a person uses a steel tape and measures 25.01, there is a very real possibility that the ACTUAL length of the pool is well under 25.00, even under 24.996. It is entirely possible, even likely, that many of the pools that have been measured as "correct" by steel tape, are, in fact, too short - especially LC pools. Fibreglass tapes can be made in such a way as to allow them to float on the water surface and thus dramatically reduce such error. I know the one we have is NOT of the floating variety and therefore measures the pool SOME amount longer than it actually is - but certainly not as badly as with a steel tape. Laser measurement, done by properly trained people eliminates the "tape sag" problem and is a more accurate method. Why is this not allowed? Are there any known situations where a pool measured by steel tape and found to be "long enough" have subsequently been remeasured by more accurate methods and found to be too short?

It had to be engineers (or liberals) that wanted to give away what wasn't theirs (or there) to give. I have spent 25 years dealing with (and sometimes enlightening) engineers, and with all respect, this has gotten far from the issue. If the pool is short, you don't report. By the way, steel tapes are just fine, thank you, if you use the proper tensioner in the proper manner while measuring. The stretch is accounted for in the sag (or vice versa), and everyone is happy. And I doubt that FINA would be happy accepting times from a pool that was 4MM short (that's 5/32 of an inch), even if the resolution was explained to them. Resolution be damned, I would rather swim in a pool that was 6 inches long (and I have, on occasion) than one that was one angstrom short. The latter would just seem wrong.

Phil, The swimmer your talking about in your FINA story was Tim Mckee, the great swimmer from the Univ. of Florida and USA, in the 400 IM in the 1972 Olympics in Munich, against Gunner Larsson from Long Beach State and swimming for the country of Sweden. You are right in your story. This race would go down as one of the closest in Olympic history and result in an international rule change. Both swimmers were clocked at 4:31.98 exact time to the hundredth. The timing device, which was by Omega was dismantled and upon inspection was found that Larson had touched two-thousandths of a second ahead of Mckee so officials determined Larson won and he was awarded the Gold medal. What was strange is that both swimmers were listed with the identical time in the record books. After the Olympics it was argued that pool walls and lanes could vary slightly making it unfair to measure time to the thousandth of a second. This is the only swimming race in Olympic history this has happened (tieing to the hundreth) and not awarding two Gold medals. It happened two times since then in the Olympics, the recent one being the Gary Hall and Anthony Ervin 50 Meter Free in 2000, and in the Women's 100 Free in 1984, with Nancy Hogshead and Carrie Steinseifer. All four of these swimmers were awarded the Gold Medal. One of my friends and Michigan Masters teammates, Larry Day (World Record Holder in the 100 and 200 Meter Fly 50-54) is currently representing Tim as an Attorney to get FINA to overturn this decision and award him a Gold Medal. Like anything the wheels of justice move slow and its very hard to overturn anything regarding the Olympics with FINA. This goes for Rick Demont, 1976 Olympic Women that were awarded silver medals against the East German women, namely Shirley Babashoff, and others. I saw Tim McKee at the 1983 Short Course Nationals, in fact he swam as a masters swimmer and won the 400 IM, keeping Jim McConica from sweeping 1st place in 6 events in taking 2nd place in the 400 IM and winning by .69 seconds over Jim. I think he still lives in Fort Lauderdale but has not competed in many years.

Hi Michael Heather, Like Wayne, I would be very interested in the measurement procedure, as I politely asked for in another thread. What is the proper tensioner, and how do you know the stretch is compensated by the sag? Why did you let the relatively ignorant conversation of people who need information go on so long without your insight and experience? A lot of people will be measuring pools and they will need good guidance - evidently you can give it. I tried to start a new thread to discuss this topic of how to measure a pool, but that thread did not go anywhere. Someone with your expertise and strong opinions could certainly have contributed. I've asked similar questions before with no answer, but do you have any evidence, including anecdotal, that FINA knows about, cares about, or has acted on length discrepancies of 4 mm? I stand by my understanding of how to specify dimensions - I do it professionally. If I were your engineer I would listen to you, and write the length as you want it (ignoring pad thickness, for now) as 25.0000000000 (-0.0000000001 +0.15) meters, Then tell the contractor something different, perhaps 25.010 (+/-.005) and you would be little wiser. That would be the average length. I would need to give another specification for the differences from lane to lane. Actually, I do have a FINA story. Way back when, a swimmer lost an olympic race by a couple of thousandths of seconds. After that, it was decided to record only hundreths of seconds, and allow ties if the times were the same. Why? Because the "dimensional tolerances" could not be maintained from lane to lane! These are the differences in length that we are now talking about. Meanwhile, could you explain your first sentence? Who is a liberal (or was that a gratuitous and irrelevant insult at people who, as far as I know, have not contributed to this discussion)? What are liberals (or engineers) trying to give away? Trying to clarify the meaning of a measurement definition is giving something away? Asking for advice is giving something away? Or were you bringing up the dead horse of the NW zone meet (but still, what would be given away?). Wayne, I assume your comment about enough rules was addressed to my suggestion about the timing pads. I am only trying to make everything consistent and avoid loopholes. If we really care about 1mm (or one angstom) than we should certainly be concerned about the width of pads, and whether they are used or not. I imagine many pools would be OK with watches, but not OK with pads, so I see my suggestion as a way to make more pools available for meets. Incidently, I am surprised a market for timing pads ever developed. Before pads, I assume pools were designed for the nominal length (25 y, 25 m, 50 m). But to add a pad would make the pool too short, so there could be no 'legacy' market, and they could only be put in pools that were designed for them. But there were no suppliers of pads . . .

To those who care about measuring pools with a (steel) tape: In the mid 1980's, one of the members of the Southern Pacific LMSC went to England on a holiday, and picked up a metric steel tape for our use in measuring 50M pools. This tape has a spring loaded tensioner that clinches the tape, and the instructions were to pull to a certain number of Newtons at a particular tempurature, depending upon the length of the pool. one party pulls at one end and another holds the zero at the other. I am giving the engineer who came up with the idea the credit for taking into consideration the elastic effect of the tape weighed against the gravitational forces at the specified temperature, without feeling a particular need for any floatation devices to be used. I do not pretend to know if the same type of device would be appropriate for use with a fibreglass measuring tape. Undoubtedly the coefficient of elongation is vastly different, and the specific gravity may be much less.

Did you know that if the water temperature changes from 90 F to 70 F a 50 meter concrete pool will get about 5 mm shorter? (No wonder those southerners get faster in the winter!) Anyway, if you measure your pool empty, be sure the sun is not shining on it, and the concrete is a uniform 80 degrees F.