Does cole phelps die on LA noire

Sadly yes, Cole Phelps dies in the ending of L.A. Noire. In the last mission,
"A Different Kind of War," you have to find the arsonist who burnt down the previous houses in your arsons desk, you is also trying to find a girl, Elsa, who was supposivly kidnapped by the arsonist. After finding the arsonist and Elsa, your friend, Jack Kelso who has helped you in the process, kills the arsonist.
As Phelps and his parter, Biggs, help Elsa and Jack out of the sewers, the sewer waters flush Cole out after helping Jack.