If the ANC Government has not fulfilled its fiscal responsibility regarding the provision of water to the Western Cape, thereby causing a National disaster, surely we are legally entitled to withhold all our taxes until they fulfil this very life-threatening obligation as a form of self-preservation.

I cannot see how the Constitution could possibly deny us a self-preservation legally entitling us to a  tax revolt.
(love to hear Pierre's legal opinion on this - Pierre De Vos is challenged right here.)

It would also the ANC restrict governments financial irregular spending, which would be a double win for the WC. 

Note, I am not referring to the DA at all. If the DA were also withholding funds in a similar manner, they would deserve the same treatment, but they aren't. 

I notice ThomasJ with a few ANC supporters cannot see the serious side of this, since creating life threatening problems are of no concern to them