How does a pool swim work?

Check how the race will be run. I've heard of several swimmers to a lane, and just circle until they're done. Someone watches to make sure all laps are completed.

I've done a serpentine, which is basically a big s-curve through all the lanes. The one I do is down and back, move over, down and back, over, until getting to the last lane where we exit. Started someone off every 30 sec and you're required to let people by. Start position was by estimated swim time.

Snake swim based on submitted [usually] 100 time.  It's still a cluster fudge and a big mash up.  Inevitably about 20% of the people put a 50 time and another 50% all put 2:00.  I've had races where every single person in front of me put a screwed up time.  That's why I don't do pool swim tris anymore.

I've personally participated in it done three different ways, and if yours isn't a general question, definitely check out the specific tri's website or e-mail the director to find out.

1) Serpentine, separated by seconds: there are lane lines, and each person starts several seconds behind the person in front of them. They tell you to stay to the right, so you theoretically can overtake people on the left and/or at walls. You swim up one lane, down the next to the left, etc. until done.

2) Several to a lane, circle swim, several different waves. This was a timed swim in which each lane had a (human) timer, and they would start several people in a lane, 5s apart. When everyone from one wave had gone off to transition, the next wave started. I have no idea how the timing all worked out, but I'm sure I could if I thought about it a while.

3) Swimming AROUND the pool (one big outside lane was marked off with buoys and lines so you couldn't cut) several times by AG.

I'm surprised you've had that much trouble.  You're fast enough that there shouldn't be that many people ahead of you.  I'm not as fast as you, but I'm fast enough that I'm usually seeded close to the front, which eliminates most of the problems in a race that I do every spring.  The biggest problems are usually back farther in the field.  Maybe I've been lucky, and the one I do is well run, and you've been unlucky enough to be in ones that weren't.

For the OP - They can also be done with time trial starts with 2 people to a lane.  Whenever someone finishes, the next person in line crosses the timing mat to start their race time, then gets in the empty spot.

Serpentine swims go much quicker.  I've done some with time trial starts where I had to wait in line more than 2 hours to start.

During our local triathlon, only two swimmers are allowed in a lane at the same time.  They must bring their own lap counter person.  The lanes are split so each swimmer stays in their half side - no circling.  When the laps are completed, the swimmer exits and the next swimmer in line will start in that vacant lane.  With 15 - 25  yard lanes available, 50 swimmers are going at a time.  Each triathlete's race begins when that athlete starts their swim.  The system works very well and efficiently.

Have fun doing what ever you're doing today!

The races that have had this are incredibly well run and organized so that isn't the issue.  The issue is that I usually put 10 seconds faster per 100 than I know I can go simply to get to the front.  That should put me in the top 2 or 3.  However, it tends to put me about 10th, where, inevitably, the 8 or 9 people in front of me spend 10 minutes telling me they put the wrong time ("hehe, oops"), but never bothered to change it so they don't have to wait for the race to start in the middle to back of the swim line.  

Then, to compound things they let open division go first so I end up crawling all over them, figuratively, not literally.  One race I got to the fourth wall and there were three wall hangers and they wouldn't part for me to turn so I had to stop, say "excuse me" and then turn.  That was my breaking point.

I'm starting to feel the same.  Too bad 'cause my 1st tri was serpentine pool swim.  But as I've gotten faster (er- less slow) the pool really can become a cluster.  DW took a pic during one of my races where there were 23 (count 'em) 23 yellow swim caps backed up waiting to make a turn.  That 400M swim was in 50M pool with 600+ athletes doing TT starts on only 5sec intervals.  This caused more contact than any of my OWS's. 

I've done 3 pool swims that were all 4 people to a lane, circle swim, starting every 10 seconds.  You estimated your 500 time to be "seeded" in the proper heat/lane but rarely that works out.

So what do you do when you want to pass, because inevitably you will not be in a lane all swimming the same speed.  Well the common courtesy was to tap the foot of the person in front, then wait til the next wall and hope they pull over to let you pass.  If you get tapped, then pull over at the next wall.  The RD's made it clear to not try to pass in the middle of the lane because circle swimming with people passing can be a little dicey and result in head on collisions.

Luckily in all 3 events, before we started the others I shared lanes with talked through the passing/tapping the foot.  Only in 1 event did 1 guy not like that idea so you ended up just dealing with it.

Good luck.

I did a pool swim with heats 20 minutes apart. the swim was 500 yards, counters provided by the local masters club. it sucked though cause I was in the last heat and there were 8 heats

3-4 per lane, circle swim.

it went pretty well, everyone in my lane seeded accurately, except the guy who swam 40 seconds faster than he anticipated