The goal of the research, he said, was to see if the conventional scientific wisdom about how much sediment the river carries in its upstream reaches holds true on its last leg to the Gulf.
“We wanted to see if there were forces at work that changed the way sediment is moved in that lower part of the river — the section where the diversions would be operating,” Allison said.
Clearly there are.
“That work significantly changed how we have to look at the lower-most river,” said Kemp. “And that makes the hydro study now even more vital,” he added, calling it the most important river study since the 1960s — “and certainly critically important for the master plan.”
Allison agreed.
The hydrodynamics study is designed to provide the engineers and scientists molding the state’s coastal master plan with the raw numbers to determine the efficacy of restoration projects that depend on the river’s volume and sediment capacity.
“We will end up with a set of very well-calibrated numerical models that can basically test any restoration scenario,” Allison said. “We’ll know if we open a diversion at Point X how much sediment it will capture, how we should operate it in various ways at various times to achieve the objectives, and what impacts operating it might have on the river and on other diversions.”
He called such insights “absolutely critical” to the success of restoration effort but not a reason to slow down the planning process.
Researchers said it was not unusual that the coastal authority did not wait for the latest river data before planning projects for the 2012 master plan and making predictions for their success. Events beyond their control played a part in that time line, they said.
