A pH of 8 is on the alkaline side. A couple of things to mention - make sure you let the water sit and degas and equilibrate for 24 hours before measuring the pH. If you measure straight out of the tap, it will give you a false reading. Secondly, make sure your pH indicator/probe is properly calibrated so you can be sure of your readings.
And yes, softer waters tend to be on the acidic side rather than the alkaline (basic) side.
If the water has sodium bicarbonate, the pH can be high, but GH, which is a measure of the concentration of calcium and magnesium, can be zero. My tap water is like that. The KH (alkalinity) is 11 and the GH is 0.