Just check on YMCA app to see all the schedules which day & time available for any activities that you're interested to join.
Maybe 2 people per lane when the pool times first open. After the first half hour on long time slots it gets to maybe one per lane. At night it does get packed and you maybe have 3-4 per lane. It's manageable though and the life guards try to make you're in the right lane with people who's speed you match
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