I'll use the definition in the US code
(1) “torture” means an act committed by a person acting under the color of law specifically intended to inflict severe physical or mental pain or suffering (other than pain or suffering incidental to lawful sanctions) upon another person within his custody or physical control;
(2) “severe mental pain or suffering” means the prolonged mental harm caused by or resulting from—
(A) the intentional infliction or
threatened infliction of severe physical pain or suffering;
(B) the administration or application, or threatened administration or application, of mind-altering substances or other procedures calculated to disrupt profoundly the senses or the personality;
(C) the threat of imminent death; or
(D) the threat that another person will imminently be subjected to death, severe physical pain or suffering, or the administration or application of mind-altering substances or other procedures calculated to disrupt profoundly the senses or personality
http://www.law.cornell.edu/uscode/18...0----000-.html
So, simulated drowning would be defined as torture.
Would you consider simulated drowning as torture? Would you consider it torture if I held you on your back. Stuffed a rag into your mouth, and then poured water over your face so that the water ran into your mouth and nose and you could not breath because any attempt to do so would mean breathing in water. Keep in mind that the rag in your mouth would keep you from coughing up any of that water. Would you consider that torture if it was done to you?