Since 1989, corporate sponsorship participation has underwritten production costs of the air and water show. The event has been managed by the Mayor's Office of Special Events since 1994.

Answer this question based on the passage: who pays for the air and water show? OK. Let's think. My stream of consciousness:
To answer the above question, the relevant sentence is: Since 1989, corporate sponsorship participation has underwritten production costs of the air and water show. The answer is corporate sponsorship participation.