You might also look and see if you have Reverse Osmosis services in your area.
They could filter out the CYA, but it can be spendy. I've heard quotes from $ 400 - $ 600.
But it might be a viable option for you instead of water replacement.
I did look and there doesn't appear to be one closer to me than Sacramento, about 3 hours away. I don't think it is really viable, but when I get the hard number for the CYA test and we figure out exactly how much water we will need to drain we can do a cost benefit analysis and see what it would cost for water and a possible fine / penalty vs finding out whether they would be willing to travel that far and the cost of RO.