Managing waste water discharge of a computing system, the computing system including one or more evaporative coolers, including: determining, by a waste water management module, a waste water discharge limit, wherein the waste water discharge limit specifies the amount of waste water that can be discharged within a period of time; determining, by the waste water management module, the amount of waste water that has been discharged during a current measurement period; and updating, by the waste water management module, operating parameters for the computing system in dependence upon the amount of waste water that has been discharged during the current measurement period and the waste water discharge limit.