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Northern Guam Watershed

Northern Guam Watershed Description
Cliffline Northern Guam Watershed

Guam is the largest and southernmost island in the Mariana Islands chain. It is approximately 30 miles long and nine miles wide with a population of approximately 168,000 people. The Northern Guam Watershed covers approximately 67,840 acres. Unlike southern Guam’s volcanic origin, the Northern Guam Watershed is a relatively flat limestone plateau that rises to 828 feet in the north. Clifflines and associated plant community is habitat to the endangered Pteropus mariannus mariannus (Mariana fruit bat). A single specimen of the endangered Serianthes nelsonii (trunkon guafi) also resides in the watershed. Barrier and fringing reefs occur around the area. A shallow cobbly, clay loam typically covers the limestone with deeper soils in depression areas.

There is limited surface drainage in this watershed area. A majority of rainfall percolates directly into the permeable limestone. Surface drainage systems are located at the southern edge of the limestone plateau. This area receives between 94 and 106 inches of rainfall per year. Underlying the limestone is the designated Northern Guam sole source aquifer. Guam’s northern aquifer provides approximately 80 percent of Guam’s drinking.

Land uses and cover in the Northern Guam Watershed as taken from Guam 2002 Census of Agriculture, September 2004, includes irrigated cropland (352 acres), non-irrigated cropland (268 acres), and pasture or grazing land (28 acres). There are an estimated 924 farm acres. Small hog operations (two to three sows) are located throughout the watershed.

A recent report from the local land agency shows agricultural lease land increased from 435 acres in 1999 to 1,631 acres in 2005. Average field size in the Northern Guam Watershed is three acres. Production on small parcels is rotated to allow year round production of local and cultural crops including beans, cucumber, sweet corn, eggplant, tomatoes, bananas, papaya, bittermelon, citrus, pechay, kangkong, okra, hot pepper, bell pepper, guava, sweet potato, yams, cassava, and taro.

The following documents requireAdobe Acrobat DocumentAdobe AcrobatMicrosoft Excel SpreadsheetMicrosoft Excel.

Adobe Acrobat Document2006 Pacific Basin Area Press Release on CSP
 Adobe Acrobat Document2006 Pacific Basin Area Press Release on CSP
 Adobe Acrobat DocumentCSP FY2006 Enrollment Categories
 Microsoft Excel SpreadsheetNorthern Guam Watershed Cost List
 Adobe Acrobat DocumentNorthern Guam Watershed Map

Pacific Islands - West CSP Contact

Colleen A. Simpson
Resource Conservationist (Pacific Islands - West)
Phone: 671.472.7467
Email: colleen.simpson@pb.usda.gov

John H. (Bart) Lawrence
Assistant Director (Pacific Islands - West)
Phone: 671.472.7470
Email: john.lawrence@pb.usda.gov

Jocelyn B. Bamba
District Conservationist (Guam Field Office)
Phone: 671.735.4108
Email: jocelyn.bamba@pb.usda.gov

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