My pool didn’t have the bottom drain in active mode unless I turned a certain handle and did a backwash, at which time it did suck water down out of the bottom of the pool. In regular operation it should be off, unless there are other basic designs which require it to always be on.
No.
The pool in question was a kiddie pool. In other words, shallow enough that a seated 8 year old’s head would be above water and she would be in no danger of drowning.
Pool drain suction pumps exert a lot of force. That is because water is heavy and takes force to move.
In the case of the girl who recently died, Abigail Taylor, the suction ripped a 2 inch tear in her rectum, through which nearly all of her small intestine was pulled out.
I suspect that when enough of her intestine was pulled into the works they started to clog, reducing suction, and that’s the point at which she was able to pull herself free, stand up, and start to walk out of the pool. Her parents report that as she walked out of the pool and fell face down on the surrounding deck. Initialy, they thought she was having a seizure. In reality, she had passed out.
The end result was that she not only no longer had sufficient intestine for absorbing nutrition, it was also insufficient to keep her hydrated. She was utterly dependent on IV delivery of both food and fluids. The problem is, the human body is not really designed for that. Long term, this destroys the liver.
Abigail died as from complications of organ transplantation to replace her intestines, liver, and pancreas. If it had been successful she would, cf course, have to have a lifetime of medication but it would have enabled her to eat and drink normally, and probably have a longer life than she would have without one. If it had been successful. Among the complications was cancer, which is a risk in organ transplantation.
A tragedy all around, really.
The reall shame? Disemboweling by pool drain had happened more than once before. Improvements have been made in the both the design of pool drainage systems, and in covers for pool drains, but they must be in good repair and properly maintained. Apparently the one Abigail sat on wasn’t.
Well, I meant in general, not just in this particular case.
Quite horrifying that a drain in a kiddie pool could still be that dangerous in mid-2007.
Back in the 80’s, I remember a guy on Howard Stern’s radio show who was on to relate a story of how he was in some sort of hospital tub (rehab?) and whoever was attending to him opened the drain while he was sitting on top it. One of his testicles got sucked into the drain. I think he had to have it removed; anyway, he successfully sued the hospital.
This article I found this morning concerns an arm becoming trapped in what I assume was the skimmer return line.
When I read about these cases I remember that as a child I was terrified of pool drains and skimmers… and was teased and told “they won’t hurt you!”
Well, it turns out my instincts were better than those of most people around me.
Mind you, they still couldn’t keep my out of swimming pools, I loved to swim - I just didn’t want to go near anyplace the water flowed out.
I remember seeing a story on that on 20/20 or Dateline.
Whew. I don’t feel so alone now. I am utterly, completely terrified of pool drains. :eek:
Water pressure is just depthdensity. Water density is 0.037lb/in^3. Assuming a 6foot pool depth, that’s (0.037lb/in^3)(6ft)*(12in/ft) = 2.7psi of pressure.
But what about the pump, you say?
Well, pumps can put out a lot of positive pressure, but they are absolutely limited in suction pressure to -14.7psi, a perfect vacuum.
The two together give a maximum pressure differential on the drain of 17.4psi
Keep in mind that a swimming pool system is a closed loop in which no air is pulled in, and no water escapes (other than through evaporation), if it’s running properly. It can be opened for maintenance reasons, but not in normal operational mode. Hell, even my pool cleaner uses nothing but positive water pressure to generate movement as well as suction.
I’ve seen over 30psi going through pool systems before (mine is typically only about 20).
Sure, but all of that 30psi is forward of the pump. The pool drain is never going to see any of that pressure, unless you hooked it up in reverse (in which case, you’ll be blown off the drain instead of sucked into it). You can’t possibly get the suction of end of the pump to pull anything beyond -14.7 psi.
Unless you have a >33ft deep pool, or somehow have the entire pool surface enclosed and pressurized, there’s no way you’re ever going to get a 30psi differential across the drain.