Identify Clean Water (sage ability)

Identify clean water is an amateur-status sage ability in the study of Forester, which allows the character to ascertain that naturally occurring water is safe to drink, largely though observation, odor, testing a bit of the water against one's tongue and the appearance of the surrounding vista. For convenience sake, the purity of the water can be judged on a purity scale of 1 to 20. A table for the meaning behind each rating is listed below. Most water that is found in nature will come from one of these sources:

• Clear, flowing water will most likely have a purity rating of 16 to 20. Most dangerous impurities will be in the form of mining run-off or animal disease which is transmitted into the water from defecation.
• Slow moving water will contain silt and will tend to have a rating anywhere from 5 to 17. The most dangerous impurities are naturally occurring diseases, such as black water fever or cholera, proliferating from detritus or defecation somewhere upstream.
• Clear ponds are spring-fed water bodies that may contain algae and will have a rating of 12 to 20, depending on the surrounding terrain and vegetation. A mountain tarn with a rock or sand bottom will be purest, while a prairie or forest pond without much silt will be least pure.
• Clear lakes are defined as water bodies that are fed by rivers; they will have a rating of anywhere from 10 to 18; like clear ponds, this will depend on terrain and vegetation.
• Stagnant ponds and lakes will have suspended silt, detritus and growing algae, with a rating of 1 to 11. This includes freshwater stagnant marshes.

Purity ratings are as follows:

Purity Rating	Water Taste	Effects
20	pure, unusually fresh	clean; no effect
19	pleasant	1 in 1000 chance of containing gastro-intestinal parasites
18	agreeable	1 in 100 chance of causing a gastro-intestinal disease
17	odd, earthy	1 in 10 chance of causing a gastro-intestinal disease
16	peculiar, metallic	1 in 6 chance of causing a gastro-intestinal disease
14-15	queer, stale	1 in 2 chance of any disease
13	bitter	2 in 3 chance of any disease
11-12	rank	3 in 4 chance of any disease
9-10	mouldy	3 in 4 chance of any disease, +1 severity
7-8	rancid, mouldy	5 in 6 chance of any disease, +2 severity
4-6	hint of decay, mouldy	7 in 8 chance of any disease, +3 severity
1-3	putrid, rotting	9 in 10 chance of being poisonous