It is never wise to drink water from rivers and streams, no matter how clear and clean the water appears. When you are working in the field you need to consider your access to clean water. If there is nothing available you will have to take steps to protect yourself by using a method of water purification. When camping or working in an area of questionable water quality, your drinking water should be boiled for at least 10 to 12 minutes. You can remove many contaminants except bacteria without boiling by using water filters. Always follow manufacturer’s directions and purchase a good quality filter unit to take into the field with you. Know how to use the filter before you leave and purchase additional filter units to have enough on hand.
Another alternative is to have bottled water available at your camp. However, this may not be an option for some remote areas you will be working in.
Other methods for cleaning water include water purification methods such as iodine or chlorine tablets, two methods used to kill water-borne pathogens. The choice of water treatment will depend upon your source of drinking water and the amount you will need.
The following web-link describes how to treat water to ensure it is safe to drink: http://wwwn.cdc.gov/travel/contentWaterTreatment.aspx