THE Logan River catchment has received another damning assessment in the 2014 Healthy Waterways report card, released last Wednesday at Berrinba Wetlands.
The freshwater catchment was graded D for the second year running while the river’s estuary was rated D-, a slight improvement on last year’s F.
The Albert River catchment continued its upward trend, scoring a B-, up from last year’s C+, while the Albert River estuary dropped from a D+ to a D-.
Executive scientific expert panel member Professor Rod Connolly presented the report card to Logan City Council’s environment chairwoman Councillor Trevina Schwarz at the launch.
Professor Connolly said freshwater streams in south-east Queensland had declined slightly overall, with the weather having a strong bearing on the results.
“Last year, which was from July last year to June this year, the reporting period, was for many catchments the driest period since we began mapping more than 13 years ago,” he said.
“So in an exceptionally dry year that means that freshwater streams tend on average not to do so well.”
Professor Connolly said the largest ongoing problem for the Logan River catchment was the lack of vegetation on the banks of creeks and rivers, known as the riparian zone.
“In the Logan (catchment) there is a lot of privately held rural lands where a lot of work needs doing and that would be where I would certainly make a start,” he said.
Professor Connolly also pointed to the city’s green field developments as a major culprit in causing sediment pollution.
“We’re undoing some of the good work we’re doing elsewhere by what we call green field development,” he said.
“So on the edges of a city they clear fell a forest to put in a development and while that is exposed soil, when it rains, the amount of sediment that comes down there and goes into the streams essentially fills those streams with what would have been 20 years of pollution overnight.”
Despite the region’s poor scores, Professor Connolly praised the work of Logan City Council in restoring water quality.
“The issues are the same long-term issues that we’ve known about for a decade and to put it in perspective Logan council is probably the most active council now in solving that,” he said.
“So they had a fairly slow burn start, a bit of a slow walk up start, but now they’re off and running.”
Professor Connolly said the Logan River emptied into southern Moreton Bay, which scored a D+ compared to the overall Moreton Bay grade of B-.
He said the bay was heavily impacted by the low water quality of the Logan River, particularly the sediment carried by the water.