News from Scott Griggs:

altYou may have noticed some construction between the levees at Westmoreland, and wondered what is happening. The City of Dallas is building an underground soil/bentonite cut-off wall along the levees to decrease the risk of water going under the levees and thereby collapsing the levees.

By way of background, the U.S. Army Corps of Engineers deemed the levees unacceptable in 2009. Following this determination, the Federal Emergency Management Agency threatened to redraw the 100-year floodplain maps as if the levees were not present. FEMA is requiring that the levees be certified to the 100-year flood standard in order avoid the redrawing of the floodplain maps without the levees.

Unfortunately, the Corps is no longer in the levee certification business. The Corps, however, has publicly stated that the probability of a levee collapse due to water going under the levees (the event the cut-off wall will mitigate) is 1 in 100,000 years even without the cut-off wall built.

Since the Corps is no longer in the levee certification business and FEMA is requiring the levees be certified or the floodplain maps will be redrawn, the City of Dallas hired an engineering and consulting firm at considerable expense. The engineering and consulting firm indicated that if the City of Dallas hired the firm to build an expensive cut-off wall, the firm would certify the levees.

As you can see, the cut-off wall is now under construction and following the completion of the construction, the firm will certify the levees and FEMA will redraw the floodplain maps with the levees present.