Oregonians are proud of the environmental resources of the state and are motivated to protect them for future generations. Where Oregonians get their water Ground water is the source of water for all wells and springs. It begins as rain or snow that falls to the ground, enters the soil, and percolates downward until it reaches the water table. Many people envision groundwater as something similar to lakes and rivers flowing in vast underground caverns. Groundwater moves very slowly, usually only a few feet per month or year.
Surface water is in lakes, streams, reservoirs, and surface depressions that capture and hold water.
Because it is visible, surface water may seem the major source of drinking water. Actually, less than 3 percent of the earth's fresh water is in streams, lakes and reservoirs. The other 97 percent is under-ground. Stream and lake water is not protected so must be assumed to be contaminated with small organisms which pose a health risk. It also may contain chemical contaminants.