Operations & Maintenance

Specialized in maintaining GWA’s standards for quality and service. Select a team or unit below to learn about their role at GWA

GWA Operations Department

Under the direction of the General Manager, Water Operations and Maintenance is composed of Utility Services Division Operations, Water Distribution, Water Production, Wastewater Collections and Wastewater Treatment. The Operations Department provides water and wastewater services in a safe, reliable, responsible and cost effective manner.

  • Utility Services Division OperationsOpen or Close
    The Utility Services Division Operations delivers service through dispatch, meter maintenance, asset management, and meter reading and acts as the centralized administrative support for water and wastewater.

    Administrative Support Unit

    Responsible for the tracking divisional budget balances and expenses, processing and posting of JDE Work Orders and daily well status reports, employee time keeping, payroll and performance evaluations, Inter-office communication and coordination with Private Management Contractor on wastewater and water personnel related issues. Creating, routing and maintaining records of memos and correspondences, and advising assigned employees of HR policies and procedures. This office serves to support Water and Wastewater Operations Department by delivering service both internally and externally on all procurement needs and capital improvement project support in areas of work order management and job costing to create an atmosphere of accountability.

    Dispatch Office

    Receive customer phone inquiries, complaints, water and wastewater emergency reports of outages and provide information to the public regarding the status of operations and services.

    Meter Maintenance

    Responsible for meter testing and maintenance to avoid revenue loss from under-registration of meters.

    Asset Management

    Responsible in the preventive maintenance of GWA’s over a thousand water and wastewater assets.

    Meter Reading Unit

    The Meter Reading Unit read over 41,000 water meters both electronically and manually. GWA currently operates two AMR read systems (Metron Farnier & Badger Read Center). Meter Readers also manually read all Sensus meters as well as report various water related incidents such as service line leakages, meter leaks, valve leaks, flooded meter sites, illegal connections, etc. Currently, this team does double duty by reading meters and assisting the Small Meter Task Force to change out meters.

  • Water Operations and MaintenanceOpen or Close
    Water Operations and Maintenance supplies each customer with a sufficient volume of water at adequate pressure and that it delivers safe water that satisfies the quality expectations of 42,000 customers.

    Line and Leak Repairs

    Performs repairs on water mains and service line leaks that are reported daily by residents. Carries out line replacement and maintenance of water mains , service lines, control valves, and pressure reducing valves.

    Pumping Station Operations

    Conducts 24/7 operations to monitor reservoir levels, booster pump station operations and pressure regulating valves required to maintain adequate pressures and delivery of water to service areas. Responds to daily trouble calls and water quality complaints reported to GWA. Assist Line and Leak Repair with isolation of water mains and service lines as needed.

    Booster Pump Station Maintenance

    Conduct preventive and corrective maintenance on 25 booster pump stations and 29 reservoirs. Maintenance is performed on altitude valves, flow meters, booster pumps, electrical controls, Programmable Logistic Controllers (PLC), Variable Frequency Drives (VFD) and related appurtenances for booster pump stations.

    Valve Maintenance

    Conducts Preventive and Corrective Maintenance on isolation valves for water distribution system island wide. Implemented a valve exercising program to operate valves on a regular basis and those that have not been operated in years. This allows team to isolate smaller areas when a main line break occurs.

    Fire Hydrant Maintenance

    Carries out Preventive and Corrective Maintenance on fire hydrants island wide.

    Leak Detection

    Perform leak detection to identify leaks that have not surfaced above ground. Assist with the reduction of Non-Revenue Water by addressing leaks which impacts real losses.


    Guam Waterworks Authority operates GIAA’s entire water system. The specific areas included are the well and transmission lines, the granular activated carbon (GAC) filter system, the reservoir, the chlorination system, the booster pump and fire pumps and the distribution system.


    The Ugum Water Treatment Plant turns raw river water into safe, drinkable water for the southern area of Guam (Ipan to Umatac). The Ugum Water Treatment Plant is designed to produce up to 4 million gallons per day (MGD).

  • Water Production/Treatment DivisionOpen or Close
    The Water Production/Treatment Division is responsible for the operation & maintenance of all water production facilities within GWA’s inventory, including deep wells, the Ugum Surface Water Treatment Plant, and the Department of Defense’s Tumon Maui Well Facility, operated under license from the U.S. Navy. The Division is also responsible for the disinfection of all processed water, and supporting operations at the Guam International Airport Authority (GIAA) Public Water Supply System. Our mission is to treat and produce water that meets potable water standards, conducting “utilities industry best practices” to ensure all water GWA produces meets Safe Drinking Water Act (SDWA) regulations, and applicable local and federal ground water rules and surface water treatment rules.


    The Deep Well Section of the Production/Treatment Division is responsible for the extraction of clean drinking water from Guam’s groundwater sources, the Northern Guam Lens Aquifer (NGLA). This section operates and maintains GWA’s 120 deep water wells, ensuring that well operations meet established environmental quality standards. The Section also monitors operating conditions and ensures production sufficient to meet daily consumption demand of our water customers. This is accomplished through the professional, reliable, and certified operators of Guam Waterworks Authority.


    The Ugum Surface Water Treatment Plant (USWTP) Section operates and maintains GWA’s only surface water production facility, which pumps raw river water up to the plant and through several steps of its membrane filtration treatment and chlorine disinfection processes. This process produces clean, safe, potable water which is stored at the plant’s reservoir and released into the distribution system, serving the southern area of Guam from the villages of Ipan to Umatac. The USWTP is designed to produce up to 4 Million Gallons per Day (MGD) but currently produces 2.3 MGD to meet customer demand.


    The Production/Treatment Division also operates and maintains the GIAA Public Water Supply System through an operating agreement between GWA and the Airport Authority. The water system is designed to produce over 700,000 gallons per day and is classified as a closed system, serving only GIAA facilities and tenants within the GIAA property.

    Tumon Maui Well

    The Production/Treatment Division operates and maintains the Air Force/Navy’s Tumon Maui Well Facility through a Memorandum of Understanding (MOU) and License from the U.S. Navy. This is Guam’s top producing well, and is designed to produce over 1.2 MGD and along with other GWA wells provides water service from upper Tumon to the village of Piti. Through the One Guam initiative for cooperation and partnership between military and civilian utility counterparts, GWA has operated and maintained the Tumon Maui Well facility to U.S. Navy standards for over 3 years. In exchange for the water produced at this facility, GWA provides water services to the military where water is needed at their new Marine Cantonment in northern Guam.

    Disinfection Section

    The Disinfection Section is in charge of maintaining GWA’s complete inventory ofchlorination systems in use at all our production facilities. This includes deep wells, springs, surface water treatment plant, Tumon Maui Well and GIAA’s public water supply system. They perform corrective maintenance as well as preventive maintenance and ensure an adequate supply of chlorine gas is available to disinfect all processed water.


    This section is in charge of all instrumentation components throughout GWA’s water and wastewater systems. Instrument Technicians troubleshoot, repair, replace and install any and all instrumentation devices. By ensuring all instruments are operational and accurate, GWA operators can monitor pumping flow rates, system pressures, reservoir levels, chlorine residuals, turbidity levels and any other parameters needed to comply when operating a water or wastewater system.


    This section is in charge of all electrical components throughout GWA’s water and wastewater systems. Electrical Technicians troubleshoot, repair, replace and install any and all electrical devices. They are also responsible to verify appropriate incoming power parameters are supplied to all GWA facilities, and ensure all facilities and electrical equipment is operational at all times to meet the service requirements for all of our customers.

    System Control Center / Dispatch Division

    Dispatch Division is responsible for monitoring both water and wastewater system operation. All water and wastewater operational activities are funneled through this division. Dispatchers are also trained to handle customer inquiries or complaints.

    System Control Center

    The Water/Wastewater System Control Center (WSCC) is the mission-critical 24/7 operational section which is responsible for monitoring, analyzing and controlling all water and wastewater system operations. The WSCC is in constant communication with system operators to ensure both water and wastewater systems are operating normally at all times. All system adjustment and operational modification instructions are dispatched by WSCC and all system activities are documented. Field data reported by operators are recorded and compiled for shift reports sent to upper management and the engineering department.

    Trouble Dispatch Section

    The Trouble Dispatch Section is responsible for receiving and handling all customer operational complaints and inquiries that deal with the provision of water or wastewater services. Work Orders are generated for each customer inquiry and then disseminated to WSCC for the appropriate operational division to verify or rectify. The section also sends out water and wastewater emergency alerts which pertain to water outages or sewer overflows. Trouble dispatchers provide information and feedback to the customer(s) in the event there is a water or wastewater issue affecting their area.

  • Wastewater TreatmentOpen or Close
    This unit is responsible to ensure that all wastewater is treated and disposed in a manner compliant with the requirements of the GUAM EPA and US Federal Clean Water Act. The unit operates six (6) wastewater treatment plants (WWTP’s) ranging from 0.1 Million Gallons Daily (MGD) to 12 MGD capacity and two ocean outfalls. GWA’s largest wastewater treatment plant at Agana was upgraded from primary to Chemically Enhanced Primary Treatment in 2013 and completed 2014.

    Northern District Wastewater Treatment Plant

    Chemical Enhanced Primary Treatment Facility Upper Tumon and Dededo is in charge in the proper operation and maintenance to comply with National Pollutant Discharge Elimination System (NPDES) permit. This facility treats at average daily flow of 5.51 MGD and disposes of all solids generated at the Layon Landfill.

    Hagatna Wastewater Treatment Plants

    This plant located in the village of Hagatna is a Primary Treatment Facility with Chemical Enhanced Primary Treatment. In 2014 enhancement to treatment process was completed. The primary role of the staff is the proper operation and maintenance of this facility to comply with NPDES permit. This facility treats at average daily flow of 5.8 MGD and disposes of all solids generated at the Layon Landfill.

    Southern Wastewater Treatment Plants

    Consists of 4 wastewater treatment facilities which include Agat, Umatac, Inarajan, Baza Garden and Pago Socio. Presently has an operating staff of 5 employees. The primary role of the staff is the proper operation and maintenance of this facility to comply with NPDES permits.

    • Agat-Santa Rita – Secondary Treatment facility with average daily flow of approximately 1 MGD
    • Umatac – Lagoon facility with average daily flow of of 500,000 GPD.
    • Baza Gardens –This Plant is now closed and sending all effluent to the newly opened Agat-Santa Rita Wastewater Treatment Plant in Agat.
    • Inarajan – Lagoon facility with average daily flow of 100,000 GPD.
    • Pago Socia treats 3,000 gallons

  • Wastewater CollectionsOpen or Close
    This unit is responsible to ensure that all wastewater is treated and disposed in a manner compliant with the requirements of the Guam EPA and US Federal Clean Water Act. The unit operates six (6) Wastewater treatment plants (WWTPs) ranging from 0.1 MGD to 12 MGD capacity and two ocean outfalls. GWA’s largest wastewater treatment plant at Agana will be upgraded from primary to Chemically Enhanced Primary Treatment in 2013 and 2014. GWA’s new Agat-Santa Rita Wastewater treatment plants(12 MGD) was completed in July 2019 and is upgraded to secondary treatment. The Umatac- Merizo Wastewater treatment plants(.39 MGD) will be completed by July- August 2019 GWA. The new Northern District Wastewater treatment plants (12MGD) will also be upgraded to secondary treatment and will be completed by 2021.

    Pump Stations

    This section is responsible for the daily operations of 78 pump stations and responding to wastewater trouble calls such as SSOs. This section is divided into 3 districts, North, Central, & South relative to the island. The Northern district manages 22 pump stations that flow both to the NWWTP and The HWWTP. The Central district manages 27 pump stations which all flow to the HWWTP. Finally the Southern district manages 28 pump stations which contribute flow to the 4 Southern Wastewater treatment plants.


    Responsible for all corrective and preventive maintenance activities for 78 sewer pump stations and 6 wastewater treatment plants island wide. Maintenance activities include all buildings, pumps, electrical components and panels, generators, and appurtenances. Furthermore the maintenance section also handles the repair and rehabilitation of sewer forcemains and gravity sewer lines.

    Fats Oils and Grease

    FOG stands for Fats, Oil and Grease. Grease is the common term for animal fats and vegetable oils. Why is FOG A Problem? When grease enters our sewer system, it acts much the same way as it does when it sticks to your pots and pans – it collects on the pipe walls and builds up until there is a clog. When a sewer line clogs, the pressure has to be released somewhere. Generally this is the lowest point available – which may mean backing up into the establishment that caused the grease, or in another building between there and the back-up. The sewage may also find a manhole and overflow – in which case it is not only a serious public health hazard, but if it gets into a storm drain and into the ocean, it’s an environmental problem as well.

  • Facility Maintenance Equipment ServicesOpen or Close
    This unit is in charge of providing technical support with regards to over 300 Fleet Maintenance, Facility Maintenance , Heavy Equipment and Support of Water and Wastewater Operations.

    Fleet Maintenance

    Unit responsible in the corrective and preventive maintenance of over 250 GWA vehicles and tracking fuel consumptions.

    Generator Maintenance

    Unit responsible in the corrective and preventive maintenance of 89 generators servicing GWA’s deepwell and pump stations.

    Heavy Equipment and Facility

    Unit responsible in the maintenance of GWA’s facilities and all of its more than 15 heavy equipments.