Real Time Monitoring of Water Quality Parameters in Corpus Christi Bay to Understand Hypoxia

Corpus Christi Bay (Texas, USA) is home to the nation's seventh largest port with numerous petrochemical facilities. This shallow wind-driven bay (average depth 3m) is very dynamic, and is typically a well-mixed system. However, the water column becomes stratified during the summer months in the south-east portion of the bay, and so dissolved oxygen (DO) in the upper-layer water column is not able to mix with the lower-layer water column. Therefore, an hypoxic condition can develop at the lower portion of the water column in the bay, and as this bay is very stochastic in nature, this condition lasts on the order of hours. It is difficult to `capture' this kind of episodic events through discrete sampling at limited locations in the bay. Our research group has developed an integrated data acquisition system which can measure horizontal and vertical variation of various water quality parameters `synchronically' over a highly-resolved spatial regime. Also, software has been developed in our laboratory which can display the horizontal and vertical variation of these parameters in real time and thereby, guides in determining the spatial extent of the water quality parameters of interest. As part of our routine monitoring of Corpus Christi (CC) Bay, we conducted an east-west transect of the bay's ship channel on November 29, 2006 and March 22, 2007. The data collected by our system suggests that the inverse estuary situation exists in the ship channel, i.e.