Join the #1 community for gun owners of the Northwest
We believe the 2nd Amendment is best defended through grass-roots organization, education, and advocacy centered around individual gun owners. It is our mission to encourage, organize, and support these efforts throughout Oregon, Washington, Idaho, Montana, and Wyoming.
Discuss firearms and all aspects of firearm ownership
Join others in organizing against anti-gun legislation
Buy, sell, and trade in our classified section
Find nearby gun shops, ranges, training, and other resources
Discover free outdoor shooting areas
Stay up to date on firearm-related events
Share photos and video with other members
...and much more!
Filtration is any of various mechanical, physical or biological operations that separate solids from liquids (liquids or gases) by adding a medium through which only the fluid can pass. The fluid that passes through is called the filtrate. In physical filters oversize solids in the fluid are retained and in biological filters particulates are trapped and ingested and metabolites are retained and removed. However, the separation is not complete; solids will be contaminated with some fluid and filtrate will contain fine particles (depending on the pore size, filter thickness and biological activity). Filtration occurs both in nature and in engineered systems; there are biological, geological, and industrial forms. For example, in animals (including humans), renal filtration removes waste from the blood, and in water treatment and sewage treatment, undesirable constituents are removed by absorption into a biological film grown on or in the filter medium, as in slow sand filtration.
The small town in Douglas County, Oregon, Myrtle Creek, has an issue with the water supply. Looks like the city is rationing three bottles of water per person. News here. (If nothing else, it is a good reminder to have backup options for the water supply and filtration systems in place.)