Commonwealth
Utilities
Corporation

Search
Close this search box.

Services

Electric Power Generation

There are five power generation facilities on the three inhabited islands of the Marianas.  On Saipan, there are three:  Power Plant #1, the largest, was designed with eight (8) power units totaling 86MW’s; Plant #2 with four (4) engines with ten (10) MW’s; and Plant #4 has six (6) engines of which only two are operational with sixteen (16) MW’s.  Presently, the plant is restricted to 36 MW with 8 MW of reserve and this includes 12 MW of power provided by an outside contractor, Aggreko. 

On Tinian, CUC owns the property and equipment associated with Telesource which is an independent power producer (IPP) that includes six engines totaling twenty (20) MW’s of which 18.5 MW are reserve power. 

On Rota, CUC owns the site and equipment of the power plant which includes six generating units that total to 6.5 MW of which 4.5 MW are reserve power.

Island Capacity Reserves Power Generation Facilities
Saipan
36 MW
8 MW

3

Tinian
20 MW
18.5 MW

1

Rota
6.5 MW
4.5 MW

1

Water

Saipan has 13 aquifers it relies on to provide 24 hour water to 12,000 customer accounts, not including the resort properties.  There are thirteen (13) Tank Service Areas (TSA’s) that supply water across the island that rely on 127 wells to provide up to 10.3 million gallons of water per day through fourteen (14) large water storage tanks.

On Tinian, they rely on one large sump area that captures rainwater that flows naturally to that low lying area.  The Maui II well which has two backup generators and four 100 gpm well pumps to supply water to the transmission main that fills the one tank in their system, Carolina Heights.  This tank provides water to the community of San Jose, the airport and outlying areas.

Rota relies fully on the main cave spring from the local mountain heights to serve as the sole water supply source for the island.  Based on the location of the cave and the installation of several pressure relief and pressure sustaining valves, the main supply line maintains adequate supply and pressure to each customer connected to the system.

Island Water Source Wells Tanks Capacity
Saipan
13 aquifers
127
14
10.3 million gallons of water per day
Tinian
Large sump area
-
1
N/A
Rota
Mountain Spring
-
-
N/A

Wastewater

Only Saipan provides wastewater treatment from two facilities, Sadog Tasi (5.2 mgd) and Agingan (3.0 mgd).  Rota and Tinian rely exclusively on septic systems and lagoons.  

The two Saipan facilities are in the process of getting upgrades to return them to their original condition when they were first built.  The current plans are to gradually expand with new modular technology sites to the North end of Saipan where in-filling sites will be targeted for added treatment capacity.

Island Tinian & Rota
Saipan
Wastewater treatment
Tinian
Septic systems & lagoons
Rota
Septic systems & lagoons