I'm on a well system with basic filtration. The water tastes great. Is it ok to add the tap water directly to the cold wort (which is cooling now), or does that risk contamination? Not really too familiar with well systems...
To answer the question you asked: "Does it risk infection", yes. Using unsanitized, (un-boiled), water CERTAINLY increases the risk of infection. It does not, however, guarantee an infection. Many people use straight tap water. I don't personally recommend it, as I figure whatever easy steps I can take to avoid infection, I'll take em, but people do it.
Is it perfectly safe? No, there's some risk. It's up to you to determine what risk level you are comfortable with.
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