I meant to reply to this, feel free to bump if nobody answers for a day or two.
So, I assume you did the flush but if not... it depends on how alkaline your water is. The main affect of using off ph water is having off ph soil. Since we're trying to stay around 6.0, if your water is under 8.0 you should be fine. Yes, your soil will be off and your plants may have negative responses to that BUT they should live through it fine.
You should get some vinegar (or cider vinegar) and add it to your water. As a really quick and rough estimate, I suggest using about 1:8 vinegar:springwater.
Best of luck