CHAPTER SEVEN 



Synthesis and 

 Conclusions 



"Then what of this river that having arisen 

 Must find where to pour itself into and 

 empty?" 



♦♦♦ Robert Frost, Too Anxious for Rivers 



The Nueces Delta is one of the most extensive marshes 

 on the Texas Gulf Coast. It is an integral component 

 of the Nueces Estuary, providing economically and 

 ecologically valuable habitat and food for many 

 estuarine and marine plant and animal species. In 

 1997, the worldwide average economic value of 

 17 ecological services provide by an estuary was 

 $9,000 per acre per year (Costanza e( a/. 1997). In 

 Texas, the total of only two recognized estuary 

 functions (commercial and recreational value of 

 fisheries) was about $5 billion dollars for the one 

 million acres of estuarine area in the State (Robinson 

 et al. 1995), or about $5,000 per acre per year. 



The flora and fauna of the Nueces Delta depend upon 

 periodic freshwater inundation events to maintain their 

 ecological functions. However, over the past century, 

 increases in the human population in the Coastal Bend 

 region of Texas has intensified the demand for fresh 

 water to meet agricultural, municipal and industrial 

 needs. From the combined effects of reservoir 

 construction, changes in land use patterns, increased 

 ground water withdrawals and other human activities, 

 the average annual volume of fresh water diverted into 

 the upper Nueces Delta since 1982 has been reduced 

 by over 99% from that before 1958 (Irlbeck and Ward 

 2000). Over time, this decrease in freshwater inflow 

 has created a non-functioning estuarine ecosystem in 

 the Nueces Delta. The natural freshwater deficit 

 imposed by evaporation has been magnified by 

 decreased riverine inflow, resulting in hypersaline 

 channel waters and soils. As a result, a "reverse 

 estuary" condition has developed where the lowest 

 salinitjr values are near Nueces Bay and the highest are 

 in the upper delta. While many estuarine species 

 tolerate this hypersaUne environment, prolonged 



Chapter Seeen ^ 7-1 



