Clear water is not the same as safe water. What would you need to test?
Select a page to enlarge it. Open the PDF for the complete note set.
Turbidity describes cloudiness caused by suspended material. Salinity describes dissolved salts; hardness relates mainly to calcium and magnesium ions. Other tests investigate microbes or chemical substances.
Water quality varies with place, time, rainfall and human activity. Record the method, location, date and units; repeat samples where possible. One result supports only the claim the method can actually test.
Clear, odourless water can contain harmful substances or organisms. A classroom filter does not establish potability. Observe approved samples under the teacher’s procedure and never drink them.
Compare upstream and downstream samples before and after rain. Select a test to reveal evidence; keep track of its units and limitations.
All values are fictional teaching data from one imagined stream. No real site or drinking-water result is represented. The notebook cannot establish safety.
albertatomorrow · Regional field science
Identify one measured property, how samples are collected and why location or repetition matters. What question can that evidence answer?
This supports removal of some suspended particles. It does not prove that dissolved chemicals or all microbes have been removed; the sample is not certified drinkable.
Why record recent rainfall when comparing stream samples?
Consider how runoff and flow can change what is carried.
Rainfall can change sediment, contaminants and dilution. Recording it helps explain differences between samples and identify other variables to investigate.
Does hard water necessarily mean contaminated water?
No. Hardness describes dissolved calcium and magnesium, which can affect lather and scaling. Potability depends on many separate criteria. Neither hardness nor softness alone certifies drinking-water safety.
Read further: USGS · Water quality →
