You just want to get the chlorine out of your water. A good rule of thumb is if you can taste it, then you should filter it. I am from south jersey and have not had a problem with my water at all.
But if you are worried about, i went to home depot/lowes and picked up a charcoal filter and put a hose fitting on one end and then put some clear hose on the out line and filter it that way. Doesn't take much of the minerals out of the water and it does remove the chlorine taste out. Plus the filter lasts a long time. Only need to replace the charcoal filter inside the thing about once a year. Then again, the replacing of the charcoal is based around how much you brew.
Hope that helps