5 or 6 meters
The diving pool at the London Olympics has to be a minimum depth of 4.5 meters, but the preferred depth is 5 meters (16 feet 4 inches).
5 meters at sheffield and coventry Last pool I dived into from a ten meter Olympic board was 16 feet deep. According to FINA (the international swimming regulatory body), the minimum depth for pool which allows 10m platform diving is 5m. Refer to the link below for the minimum dimensions (including depths) of pools which may be used for the various Olympic diving events.
1 diving board and8 diving blocks!
The Deep End or diving zone
100 feetby 50 feet by 14 feet at deep end and 3 feet at other end
Swimming races and diving