A New Dance Step at City Hall: Mayor Tom, Dave Neumann Are Doing the "Levee Slide"

The Dallas Morning News's City Hall blog today carries two items in which Dallas city council member Dave Neumann and our mayor, Tom Leppert, alternately bitch about and then sort of pooh-pooh the problems the city is having getting the Trinity River levee system repaired.

Dallas must fix its levee system back to an acceptable level, or the feds will declare a huge swath of the city a dangerous flood zone. Property owners there will be required to buy expensive flood insurance.

Why? Because they're in a dangerous flood zone.

Here is what gets me about the approach these guys, Neumann and Leppert, always take to the issue of levee safety: All they ever want to talk about are ways for Dallas to skate out of the expense associated with repairing the Trinity River levee system. They don't talk about or show you pictures of the issue -- photos of Trinity River levees caving away like wedding cake left out in the rain and directly threatening residential neighborhoods.

I'm not talking about pictures I took with my phone. I'm talking about photos published in the Appendix G to the 2007 Corps of Engineers Geo-technical Trip Report, Page Four, showing "levee slides" (places where the levees are caving in) -- three in a row right across from a West Dallas neighborhood! Or you might take a gander at pictures in the same report showing places where the city piled dirt into a levee slide and caused an even worse slide by doing it. Or pictures of places where the city just threw up its hands and stretched black plastic over the levees.

The thing Neumann is all wadded up about today is a requirement from the Corps that the city go back and carry out a new kind of test on the levees called a "fully softened shear strength" test. I know it sounds hopelessly, boringly technical, but it's not, and you already know the answer: You can pile up clay soil in this part of Texas, stomp on it, pack it down real good, and it will be hard as rock and waterproof. That's how they built the levees.

But, wait.

What happens to your hard-as-rock clay mountain when the weather gets real, real North Texas hot and dry as toast? The clay cracks up right? You've seen it in your yard. Then what happens next time it rains? Water gets in there and unpacks all that packing you did.

Four years ago the Center for Transportation Research at UT Austin carried out research on this problem at the request for the Texas Department of Transportation. TxDOT asked them to do it because the highway department was experiencing repeated and sometimes very expensive failures of highway embankments built of the kind of clay we have right here -- Eagle Ford Clay, the clay in our levees.

The UT research found that normal cycles of wet and dry weather tend to suck out all of that compacted strength in clay embankments, leaving the embankments with a strength equivalent to plain old mounded up dirt.

So now go back and look at those pictures of levee slides all up and down the Trinity River system that the Corps published two years ago, and you start to see why they're so urgent about getting Dallas to explore this issue. Has the public been told it is safe from flooding because of compacted clay levees when in fact it is not safe?

Then look again at that neighborhood behind the levee in the one photo. Neumann and Leppert want the Corps to let Dallas out of deadlines and requirements that would force the city to warn those people in those homes that they may be less protected than they thought they were. But why is that a good goal for the city to seek?

How about warning the people? How about telling them the truth?

With help from Halff Engineering, which for decades has gobbled up a fat share of the money and work on Trinity River levee system, Dallas officials now boast that they have joined something called the "National Levee Issues Alliance." In fact this was a bunch of ward-heelers in East St. Louis until Dallas joined up. Now it's a bunch of ward-heelers in Dallas too. The purpose of the Hey-Buddy-Give-Us-A-Break-Willya Alliance is to squeeze the Congress to give local communities a pass on new tougher levee standards that came out of the Katrina disaster. But guess what? This kind of thinking and this kind of politics is precisely why the Katrina disaster happened in the first place.

Never ... ever ... not once ... do any of these guys express urgency about doing something to protect people in places like West Dallas from the next one. You know why? Because West Dallas is Dallas's Ninth Ward.

Instead, Leppert and Neumann are all working to help make the next one happen. May history remember them.