GEORGE H. WARD 



Center foi Research in Water Resources, 

 University of Texas, Austin 



MICHAEL J. IRLBECK 



U.S. Bureau of Reclamation, Austin 



CHAPTER THREE 



Hydrography 



INTRODUCTION 



"Water is the blood of the earth, 



and it flows through its muscles and veins. 



♦♦♦ Kuantzu (late 4th Century) 



The Nueces Estuary and Delta are subject to numerous 

 hydro-meteorological forces, including a combination 

 of river flow, precipitation, peripheral runoff and 

 forcing from wind and tide. Each of these influences, 

 in isolation or in combination, may gready affect the 

 quality and quantity of estuarine habitat available. Such 

 hydrographic events can alter water chemistry [e.^., 

 salinity and nutrients); transport detrital material; cause 

 large volume exchanges between the bay, delta and 

 river; and make accessible or restrict habitats available 

 for estuarine aquatic organisms. Therefore, 

 interpretation and analysis of the effects of the 

 demonstration project and resulting biological 

 responses required a comprehensive understanding of 

 the hydrography of the area during the study period. 



OBJECTIVES 



1) To quantify (by direct measurement and data 

 analysis) the hydrographic interactions of the 

 upper Nueces Delta with the Nueces River and 

 Nueces Bay during the study period (October 1, 

 1994, through December 31, 1999); 



2) To identify and describe significant hydrographic 

 events during this period; and 



3) To describe the observed changes in the hydraulic 

 characteristics of Rincon Bayou resulting from the 

 demonstration project features. 



Chapter Three ♦ 3-1 



