CLARENCE VALLEY consulting engineer Trevor Jones claims the levee protecting Grafton from floods remains deficient at some points and opens the city up to potential disaster.
Mr Jones, who contributed his expertise to the levee's model testing and construction in 1971, believes it has stood up to the job but is still flawed.
He said eyewitness accounts from people in Grafton during the 2001 March flood had reported water levels being much closer to the top of the levee at Fry Street than other sections around the city.
The reason for this, he explained, was because the differing height in normal water level flows throughout parts of the river had not been accurately plotted during the levee's construction.
He said this had created a situation where floodwaters may have been well below the levee at points close to Prince Street, for example, but appeared higher at Fry Street.
Although he was quick to point out the Grafton levee's effectiveness during past floods he said the height discrepancy could be telling if a massive flood hit the city.
"It's very important that something is done before another flood comes that may over- top the levee at the low points...it's four years since the last flood and still nothing's been done...it puts the city of Grafton at risk to potentially millions of dollars of damage," he said.
He believed the necessary work to correct the levee's height would not be costly and was generally a matter of extending the blocks by a few centimetres at points of concern.
If the uneven levee height persisted until another large flood, he said more water would be forced over the le- vee's low points, causing more concentrated damage in parts of Grafton nearby.
Mr Jones also believes sandbagging the top of the levee is the short-term answer to prevent flooding if the work to raise its height is not done when another flood hits.