If you live in USA: www.epa.gov/ground-water-and-drinking-water
If you lice in Australia:https://www.nhmrc.gov.au/guidelines-publications/eh52
Most countries have their own guidelines, basically, they analyse the following parameters: pH, conductivity, turbidity, nitrates, total Nitrogen, ammonia, phosphates and total Phosphorus, total dissolve solids, DO( Dissolved Oxygen), E. Coli.
They may also do some analytes such as trace metals and organics.
The most stringent guidelines are for drinking water, then swimming pools, where they would test for chlorine.
In fishing they would consider E. coli and suspender sediments, trace metals and organics.
Some water are OK for boating, canoeing and kayaking but not for human contact? You can not just dive in .
Sorry, there is not a short answer. You will need to go to government guidelines.