Experts gather water quality data before beginning harbor deepening

Published Sept. 25, 2014

Editors Note: This is the fourth in a series of articles to explain environmental monitoring efforts associated with the Savannah Harbor Expansion Project (SHEP). This series focuses on the various monitoring activities that must take place before construction begins.

SAVANNAH, Ga. -- Scientists and technicians recently completed intensive water quality monitoring in the Savannah harbor and estuary in preparation for the upcoming deepening of the harbor and shipping channel.

The monitoring program, part of the Savannah Harbor Expansion Project (SHEP), gives the U.S. Army Corps of Engineers valuable data on water conditions in the harbor and surrounding areas. The data establishes a baseline of existing conditions before any changes occur from the harbor deepening. By deepening the harbor from 42 to 47 feet, the SHEP will allow larger ships to call upon Savannah’s Garden City Terminal with heavier loads and with fewer tidal restrictions.

“The data we collected gives us a comprehensive snapshot of the current existing conditions of the Savannah River and the estuary,” said Bryan Robinson, a hydraulic engineer for the Corps’ Savannah District. “The data will give us a good baseline – a good tool – to measure our mitigation efforts as the harbor is deepened."

In the $1.1 million research effort, the Corps’ Savannah District gathered data from sensing devices placed temporarily in the river and estuary, according to Robinson. They also collected data from existing gauges permanently in use by the U.S. Geological Survey and funded separately. Contractor Dial Cordy and Associates of Jacksonville Beach, Florida, conducted the field work and data-collection for the Corps.

The USGS captures continuous data through a system of permanent gages in the Savannah River. Under the SHEP pre-construction monitoring effort, Dial Cordy’s workers deployed an additional 13 temporarily at additional depths and locations. The added gauges measured dissolved oxygen, water temperature, salinity. Dial Gordy and Associates also gathered velocity and flow readings on the ebb and flood of the river during autumn tides in October 2013.

“The information we gathered will help us refine our computer models,” Robinson said. “Few models have this much data to work with. Collecting such a robust dataset helps show our dedication to protecting the water quality in the Savannah River by creating the most accurate predictive tool for adaptive management possible.”

The water quality monitoring program is the most expensive of the pre-construction monitoring programs for the SHEP.