Pools in the US are generally either 25 yards (short course) or 50 meters (long course).
50 Meter Pool
A 50 meter long pool is considered an “Olympic-size” pool and typically holds around 500,000 gallons of water. Additionally, a true “Olympic-sized” pool has a depth of at least two meters and 10 lanes, with a width of two and a half meters each. 50 meter pools are used in the Olympic Games, World Championships, international competitions and other swim club competitions during the summer season.
25 Yard Pool
The U.S. is the only country that doesn’t use the metric system – and it’s therefore the only country that has a regulated distance of 25 yard pools for college and high school swimming competitions. Neighborhood pools, recreation pools and NCAA competition pools are typically 25 yard pools.
25 Meter Pools
Meters and yards may seem like similar lengths to those outside of the competitive swimming world, but swimmers consider them to be very different. 25 meter long pools are slightly longer than 25 yard pools and are primarily used in international competitions.
To differentiate between pool sizes for swimming times, the following descriptions and abbreviations are used:
- Long course meters, or LCMs, for 50 meter pools.
- Short course yards, or SCYs, for 25 yard pools.
- Short course meters, or SCMs, for 25 meter pools.
For example, one swimmer who competes internationally will have three different times for their 100 freestyle event: a LCM, SCY and SCM time. There are world records for SCM and LCM races, but only U.S. records for SCY events.
33 1/3 Meter Pools
Increasingly rare to find are the 33 1/3 pools, which were built to accommodate he needs of water polo. There are many pools with unregulated lengths that are used for training purposes; however, for a sanctioned meet, the pool length must be measured and verified.