Pursuant to Presidential Decree No. 198 (Provincial Water Utilities Act of 1973), Mapandan Water District was formed to perform the following duties:
- Acquiring, installing, improving, maintaining and operating water supply and distribution system for domestic, industrial, and agricultural uses for residents and lands within the boundaries of such districts;
- Providing, maintaining and operating wastewater collection, treatment, and disposal facilities; and
- Conducting such other functions and operations incidental to water resource development, utilisation and disposal with such districts, as and necessary or incidental to said purpose.