Industry consistency in pollution reporting

The Water Services Association of Australia (WSAA) will initiate talks with the federal Department of the Environment and Water Resources (DEW) to improve the National Pollutant Inventory (NPI) data collection and reporting procedures.

WSAA technical director, Peter Donlon raised concerns following reporting inconsistencies found among major water authorities.

These inconsistencies related to chlorophenol levels, which were a common component of pesticides.

"Each year, the NPI, which is an internet-based database, provides public information on the types and amounts of 90 substances being emitted to the Australian environment," Donlon said.

"Chlorophenol is one of 90 substances reported on, but is rarely found in treated wastewater. We know that of the water authorities that do test for chlorophenols, the vast majority of levels are so low they are undetectable."

Donlon believes the situation is arising due to a number of different water authorities interpreting the required data collection and reporting requirements in different ways. This is leading to inconsistencies in their figures.

"If water authorities currently test for chlorophenol, it is a common convention to use half the detection limit as an actual number in their calculation, even if contaminants are not affected," Donlon said.

"Where water authorities do not conduct testing, the federal government requires that default values are used, whether chlorophenols are present or not.

"Utilities are then required to multiply the default values by the volume flowing into the treatment plant, which can result in abnormally high numbers being reported. These numbers bear no relation to actual discharge amounts of chlorophenols."