Dag Nommedal: There are three major natural processes which will affect long-term 

 changes in south Louisiana that we cannot manage. One is the eventual diversion to 

 the Atchafalaya. The second is hurricanes. Thirdly, there is a tremendous amount 

 of evidence from tidal gauge records and climatic models that dramatic sea-level 

 rises have just begun. We have no means or structures to deal with these problems. 

 We should, thus, start discouraging development in the lowlands of Louisiana. We 

 can not afford to lose New Orleans, but we don't want to create other potential 

 traps like it. 



Gary Bloize: Is there anything that can be done to protect the barrier islands? These are 

 very important with regard to avoiding the loss of State lands and oil and gas 

 resources to the Federal Government. 



Ron Boyd: Instead of protecting the coastline for the purpose of saving State revenues, 

 Louisiana should establish an agreement with the Federal Government regarding a 

 fixed boundary. There are, nonetheless, a range of options for barrier island 

 protection, most significantly, sediment bypassing at inlets and nourishment of the 

 islands from the available sand sources such as in tidal deltas and nearshore zone. 

 This sand can be placed back on shore and stabilized by vegetation, resulting in 

 significantly slowing down the rate of erosion. Experience has shown that purely 

 structural approaches such as placement of rock walls are generally not effective. 



Johannes van Beek: Although there are processes we cannot stop, barrier island erosion 

 is artifically accelerated by man's actions. If man can accelerate erosion rates, he 

 should be able to decelerate back to rates attributable to natural processes. We 

 must learn how best to do that in order not to be surprised by natural disasters. 



Clarke Lozes: Since 1950 Plaquemines Parish has taken upon itself to initiate freshwater 

 diversions and presently there are three structures operating and a fourth proposed. 

 We are trying to improve their design and management, while at the same time, we 

 are taking other steps to decrease the number of new oil and gas canals in 

 wetlands. These may be short term approaches, effective within 100 years, but 

 people are living in Plaquemines Parish today. It is necessary now to take definite 

 action on some projects and these might hopefully lead us to a longer term 

 management plan. 



John Uhl: What approaches can economically be taken to return the system more to 

 equilibrium and dominance by natural processes? 



Raphael Kaznnann: The only thing we can do is build diversion structures which operate 

 automatically during high flows and do not cut off sediment in the Atchafalaya by 

 building spoil banks which keep the sediment from spreading out. But this comes 

 into conflict with flood protection and navigation interests. 



Sherwood Gagliono: Dr. Kazmann assumes that the amount of water coming down the 

 Mississippi will remain the same. What are the prospects that states to the north 

 will divert water to other drainage basins? 



Raphael Kazmann: The principal advocate of this has been Texas. If it were pure water, 

 it would have to be pumped 4,000 ft to use it for irrigation. Actually the sediment 

 loads would defeat this approach. Diverting water from Arkansas River reservoirs is 

 more feasible, but this river does not contribute much water to the Mississippi. 



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