Information server for southern Guam natural resources

Southern Guam watersheds

All surface and groundwater in Guam discharges into the Pacific Ocean. Of Guam’s 100 named streams and rivers, 46 drain directly into the ocean. This means that southern Guam has many small drainage basins, which can be grouped into fourteen large watersheds. The main topographic feature that defines many of the watersheds is a mountain ridge running along the western coast. It divides southern Guam watersheds into small and steep areas with short streams in the west, and broader floodplains and longer, larger rivers in the east.

The following are the southern Guam watersheds:

1. Agat watershed
2. Apra watershed
3. Cetti watershed
4. Geus watershed
5. Inarajan watershed
6. Malojloj watershed
7. Manell watershed
8. Pago watershed
9. Taelayag watershed
10. Talofofo watershed
11. Toguan watershed
12. Ugum watershed
13. Umatac watershed
14. Ylig watershed

Protecting southern Guam watersheds from point and non-point sources of pollution requires a better understanding of watershed topography, vegetation, soil properties, roads, land cover information, badlands, and many other features. One of the rationales behind this website is to serve such information to any interested parties.


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