Zoning is a about control, in part that favored contractors and builders have their "just deserved" monopoly.
From what I've been reading, there are a lot of people who are blaming much of this on over expansion in low lying areas. Proper drainage is non existent in many places. Some areas have several inches of water to contend with. While others are practically up to the roof line. And Houston is as flat as a board. 30 years ago where excess storm water would harmlessly run off, today backs up and floods homes and businesses that didn't exist before.
The National Flood Insurance Program, (which is currently over $24 BILLION in the hole), has stated that well over 50% of reoccurring flood damage in the country is in the Houston area. And let's face it, when you have 3, "500 year floods" in just 3 years, it makes you wonder why? People keep collecting settlements for flood damage on the same homes over and over. The payouts are ridiculous. They told of one home owner who has received over $800,000.00 in payout claims, on a house that is only worth $225,000.00.
It would be cheaper for the Federal Government to simply bulldoze those houses, and build the people new one's on higher ground. Bad zoning, coupled with poor storm water infrastructure, can make something like this much worse. It appears this time it really has. People are going to be asking a lot of questions after this mess is finally cleaned up..... If it ever is. Much of it could end up like the Lower Ninth Ward in New Orleans. Nothing but weeds, driveway's, and slabs where homes once existed.