The Guam Power Authority (GPA) is a public corporation established by the Guam Power Authority Act of 1968 in May 1968. Guam Code 12 Chapter 8 sets the legal definitions, empowerments and limitations for the Authority.

Guam Power Authority is a vertically integrated electric utility that provides service to 45,751 customers with an annual budget of approximately $291 (FY 2006) million dollars. It is governed by elected five member Consolidated Commission on Utilities and regulated by the Guam Public Utilities Commission which sets the electric rates.

Current peak system demand to date is 281.5 MW a 98% reserve margin. GPA has an installed generation capacity of 552.2 MW gross including 181 MW from Independent Power Producers. GPA has organized 210.6 MW of its base load capacity under two Performance Management Contracts. These contracts provide private management using public employees to operate and maintain the plants. These contracts allow for performance-based incentives to plant operating costs. Furthermore, the Authority has installed 663 miles of transmission and distribution lines and operates 29 Substations throughout the island.

A Mitigation program is underway to harden GPA facilities against typhoons with a $20mil electrical underground program in FY05 and plans to place transmission and distribution feasibilities underground by FY13 @ $200mil.

Utility Rate Comparison

Name of Utility
Residential Rate (cents/KWH)  
Guam Power Authority 23.69
Commonwealth Utilities Corp.(CNMI) 24.59
Hawaii Electric Light Co. Inc.(HELCO) 34.26
Hawaii Electric Co. Inc. (HECO) 22.99
Maui Electric Co., Ltd. 26.64
Molokai 34.03
Lanai 22.59
San Diego Gas & Electric Co. 12.95
PECO Energy Co. 15.35
Public Service of N. H. 14.03

Contact Information: 
Main Business Office 
Monday - Friday 7:00 a.m. - 6:00 p.m.
Mailing: Route 16, Bldg. 1911 Harmon, Guam 96915
Telephone: (671) 647-5787 /9
Fax: (671) 647-5810 


On June 30 1950, Public Law 1-12 had Guam's water/sewer utilities under the jurisdiction of the Department of Public Works, since then the utility agency has undergone several manifestations to its present state as a public corporation; the Guam Waterworks Authority (GWA). Guam Code 12 Chapter 14 sets the legal definitions, empowerments and limitations for the Authority

Guam's estimated sustainable yield approaches 90 Million Gallons per Day to 38,000 customers. Our drinking water is derived from several sources including ground, surface and spring water.

The island's principal source of potable water comes from groundwater contained in the aquifer beneath the northern half of the island. Groundwater is pumped from this underground aquifer into the water distribution system by 110 water wells producing 30 million gallons a day. The water system includes 470 miles of transmission lines and 24 booster pump stations.

Surface sources used by GWA include an impoundment on the Ugum River that produces 2 million gallons a day and water purchased from the US Navy Water System at FENA Lake that produces 9 million gallons per day; of that 3 million gallons go to GWA. GWA's current financing plan includes $70mil for immediate capital expenditures in 2005 and $100mil in 2006.

The normal size for residential is a water meter is 3/4". A deposit of $32 is required for an existing water line with a monthly charge of $9.26 and $2.40 per thousand gallons up to five thousand gallons. The deposit rates increase with larger service meters. Commercial water rates are based on meter size. Ranges from 3/4" @ $9.26 + consumption rate @ $5.49/per gal. To 12" @ $239.46 + consumption rate @ $5.49/per gal


GWA system services 22,000 customers and consists of 7 wastewater treatment plants, 72 sewer lift stations, 32 storage reservoirs and 80 miles of collection lines.

A $20 deposit is required for an existing residential sewer service line with a $22 monthly charge for residential customers. The commercial wastewater rates are based on business category @ 1,000 gal water consumption from $3.02 to & $10.21 in addition to the applicable base rate.

Contact Information: 
Main Business Office 
Monday - Friday 8:00 a.m. - 5:00 p.m.
Mailing: 578 N. Marine Drive, Tamuning, Guam 96913
Telephone: (671) 647-7800/03/16/17
Fax: (671) 649-0369


Water quality is monitored and enforced by the Guam Environmental Protection Agency (GEPA) which was established by Public Law 11-91 on March 3, 1973, and is mandated with ensuring that a “high quality of air, land and water is maintained in Guam”. 

Contact information for GEPA:
Mailing:  P. O. Box 22439 GMF, Guam 96921
Main Telephone: (671) 475-1658
Communications: (671) 475-1623
Fax: (671) 477-9402

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