Chlorine Removal? Is 99% enough?

Chlorine kills microorganisms and beneficial bacteria so it's really a no-no for plants. That being said, a small amount (70ppm) won't do much harm but you'd have to get a ppm reading from your de-chlorinated water. If, as ernsttwwg says, you leave that water out in an open container for a couple of days, the chlorine will dissipate and be ok to use. The other way is as you suggested - boiling the water for 15 minutes will also remove it... but then you'd have to let it cool down to at least room temperature and increased your electric/gas bill! Good luck!

You can let it sit out in an open container for a day or two.