rain, weather, annual, monthly
aquifers, recharge, irrigation, use, conservation
rivers, lakes, watersheds, wetlands, pollution
1861, Vanport, 1964, 1996, flood risk
dams, hazards, hydroelectricity, dam removal, bridges
total use, water rights, use categories
surface, ground, bottled, contaminants
water rights, shortages, Umatilla, Klamath