WATER TREATMENT OPERATOR 3. JOB SUMMARY. Under the direction of system management personnel and Water Treatment Operator 4, the Water Treatment Operator 3 is responsible for the operation and maintenance of all production, treatment, storage, and recharge facilities. JOB DUTIES AND ESSENTIAL FUNCTIONS. Responsible for a variety of tasks and duties, which may include, but are not limited to, the following. Day-to-day operation and maintenance of a...