Lasers as Tool to Study River System

Lasers will be used as part of a 12-month study of the Mary River aimed at generating a clearer understanding of how rising sea levels will affect the catchment, according to a report.

Civil engineers from Charles Darwin University are leading the $200,000 project on behalf of the Territory Government to assess the effectiveness of several man-made barrages.

Professor Eric Valentine says the study will use the latest technology to track the movement of water around the barrages and across the floodplain.

"We'll be surveying the floodplain in various ways and we're hoping to use a lidar technique," he said.

"This is an aerial-borne laser measurement technique to discover the topography of the land and that information will be used in our numerical models to monitor the flows in the system."

The Northern Territory Environment Centre says studies are not enough to stop saltwater intruding into the Mary River.

The centre's Stuart Blanch says the barrages have helped to rehabilitate several thousand hectares of dead tea trees on the floodplain.

"But there's still around 15,000 hectares of dead tea trees, which is a bit of a biological desert.

"That's about 7,000 times the size of the MCG, so there's a lot of rehab work that needs to be done."

The Amateur Fishermen's Association has welcomed the study, providing it is backed up by action.

The association's Chris Makepeace says the Government needs to maintain the barrages to stop saltwater moving further upstream.

"The result of that could well be saltwater in Corroboree which is ... something that we're not at all happy about.

"The second thing is that right now we also have problems with siltation in the lower part of the river so it's really difficult to get boats down from Shady Camp except on high tide."