Piscine du Grand Parc

I used this facility at 5 PM on a weekday and it was fairly busy. It is clean and bright. The water was clean and odour-free. Only one lane is open for use of fins and paddles; you cannot use them in other lanes. And, despite lanes being marked with different speeds, people swam in whatever lane and didn't move to a slower lane if they were in the wrong one.

The unisex changing stalls have two doors - one from the entrance to the building and one that leads to the pool; unique locking mechanism! Lockers are available for a fee, after one exits the change room, but you can also take your bag out on deck. There is a unisex shower area, as well as a few private shower stalls just before you go out on pool deck.

Swim caps and brief-style bathing suits (for men) are required, which means nothing that looks like shorts or street clothing is permitted. It was relatively crowded both times I used it.

A busy pool with no lane control. The lane ropes are loose, so with so many people swimming (many swimming very badly), it was pretty choppy. It is a great facility with eight wide lanes, so it's easy to pass people, over two metres deep the whole length, 28ºC, and paddles, fins, etc. are all allowed. The changing rooms and showers are fine and at €4.60 it's good value. (A euro is also required for the locker, and is returned). If you bide your time and keep an eye on the lanes you may be able to slip into a quieter lane; if you're a fast swimmer people will avoid you.
Opening hours and days are variable (as they are all over Bordeaux) so check the schedule on its website in advance.

It is in a roughish neighborhood (at night) but well worth a try during the day, as it is such a great pool. Clean water and very few people - at least when I visited.