Arthur E. Berman''s response to William Meaney''s Letter to the Editor "Subsidence has many Causes":
I appreciate Mr. Meaney’s comments regarding my article in the October Bulletin, “The Debate Over Subsidence in Coastal Louisiana and Texas”. He is correct that the article did not specifically address geological differences between Texas and Louisiana coastal regions. The experts quoted in “The Debate Over Subsidence in Coastal Louisiana and Texas” did not address the distinctions that Mr. Meaney notes between the geology of Texas and Louisiana perhaps because this is not central in their view to what really needs to be understood and resolved with respect to subsidence.
It is important to note that the article published in the October Bulletin was significantly abridged and did not include approximately 20 figures that might have clarified some of Meaney’s concerns. I suggest he review the Web version when it is available to decide if his issues were or were not in fact covered.
What I addressed in my October Bulletin article and what Mr. Meaney is responding to is chiefly the geological component of subsidence as a factor distinct or in addition to the man-made causes of subsidence. Technical Report 50 revealed that, when benchmark velocities were systematically calibrated and measured in Louisiana, new insights on total subsidence were gained. Until a similar method and approach is applied to Texas, it is largely speculative what subsidence differences may exist between Louisiana and Texas. It seems reasonable that much would be learned and gained from such a geodetic analysis in Texas.
The Houston Galveston Subsidence District has shown that very high rates of subsidence have occurred in the Houston area. While Subsidence District’s data indicates that these rates have declined or ceased in some areas, other parts of the Houston metropolitan area continue to subside in a manner and pattern that is difficult to explain. This means that there is still much that is not understood about subsidence in an area that probably has the most data and sophisticated measurement technologies of anywhere in the United States.
The public deserves to know what the scientific community has to say about subsidence and its affect on their lives and property. Government needs to understand liability issues for flooding related to subsidence. Scientific experts and administrative agencies need to get beyond what must seem like meaningless differences and distinctions to the general public. Scientists and agencies such as the United States Geological Survey, National Geodetic Survey and Houston Galveston Subsidence District must tell the public what information is needed and what it will cost in order to provide answers to their questions and concerns. I suggest that conducting a measurement study in Texas using the same approach that Technical Report 50 provided for Louisiana is a logical and necessary first step in this process.
Respectfully,
Arthur E. Berman