Coastal Subsidence, Sea Level and the Future of the Gulf Coast

Houston Geological Society and Engineering, 
Science and Technology Council of Houston
join forces to increase public and governmental awareness
of an impending, but silent geologic disaster
By Cheryl Desforges, Continuing Education Committee Chairman, and Robert Traylor, TCEQ
Inundation of the Louisiana and Upper Texas Coasts is becoming one of the great geological disasters of the 21st century.  This could have a huge economic impact not only to the inhabitants of the Gulf Coast, but also to our whole nation.   The public has become aware of subsidence through press coverage of the elevated frequencies of flooding and increases in the loss of coastal areas in recent years.  Unfortunately, the press and even some governmental agencies have only focused on identifying man-induced causes, such as fluid withdrawal from groundwater and petroleum extraction, as well as sea level rise due to global warming.  As scientists, who are intimately familiar with the Gulf Coast, we know this subsidence is primarily due to the complex geological setting of the Northern Gulf Coast Basin itself, as well as contributions from man-induced causes in isolated localities.  Today’s scientific analysis does not allow us to quantify the proportion of each cause across the region.  The major impediment to this type of analysis is the difficulty measuring vertical tectonic movements, because of an inadequate and outdated datum reference plane.    Research has been conducted in Louisiana to enable quantification of the various causes of subsidence, but has not been carried into Texas. 
 
Planning for significant and costly public works projects is currently underway in Louisiana and at the Federal level.  Most efforts to date have been directed at programs that would help to restore wetland areas of the coast.  However, recognition that the entire coast is subsiding, including populated areas, have prompted some to call for massive public works projects.  These include building coastal levees to protect life and property.  Input from scientific evaluations of all the causes of the problem is now critical, so we, as a nation, can direct these public works expenditures to projects that will have satisfactory outcomes.
To increase the awareness of the issues, the HGS and ECH are organizing a three day conference “Coastal Subsidence, Sea Level and the Future of the Gulf Coast”, to be held November 3, 4 and 5, 2005.   The first day of the three-day conference will be devoted to understanding the reasons for subsidence, how to measure them, and how to analyze for each component’s contribution to the overall subsidence budget.  On the second day, the focus will be twofold: one part on assessing the economic/cultural impact and the second part on reviewing mitigation efforts, options, and consequences.  A field trip on the third day will visit sites of active faulting and subsidence within the Houston area.
 
Conference participants and speakers will include contributions from the scientific community, government agencies, elected officials, construction and real estate industry representatives, members of the media, and the general public.  We invite you to join us for this event and also ask that you help spread the word about this issue.  We are also seeking corporate sponsors to help defray some of the expenses for this non-profit community service project, so please encourage your companies to become sponsors.