Roadside run-off in tropical Queensland tidal wetlands

Jeston P1, Loft F1, Kiem S2

1Catchment Solutions Pty Ltd,

2Department of Transport and Main Roads

Abstract:

There have been limited studies undertaken in Australia on road-side water quality run-off within Coastal areas (Drapper, 2000 & Ball, 1998).  This investigation into the stormwater run-off from the Joint Levee Road (in Mackay) into the tidal wetlands addresses this knowledge gap.  The stormwater monitoring program was undertaken over three wet seasons (2017 to 2019).  Stormwater quality samples were collected at ten sites along the Joint Levee Road, at three consistent distances away from the road shoulder.

DIN concentrations decreased 17.1% down the embankment.  Total Recoverable Hydrocarbon (>C10-C40) concentrations decreased 44.4% down the embankment.  Sediment concentrations also declined with flow down the embankment.  TSS and TRH concentrations found in this investigation were lower than the results reported in the study by Drapper (2000).  These lower results may be due to improved pavement materials and road design (since 2000) to allow efficient sheet flow along the Joint Levee Road.

Stormwater monitoring of run-off demonstrated an improvement in water quality as the stormwater flowed down the vegetated road embankment.  Based on three years of wet season monitoring, key improvements in stormwater run-off are demonstrated with the reductions in the DIN, sediments and hydrocarbons.  This investigation demonstrates that vegetated road embankments within tropical wetland and tidal areas have a key role to play in the management of stormwater run-off.


Biography:

Philip Jeston, Project Coordinator and Senior Environmental Scientist – Catchment Solutions

MEnvMgt, BSc, GradCertMgt, AssDipAppSc, MEIANZ

Philip commenced his career in science over thirty-five years ago as a Cadet (Technician) working for the Department of Primary Industries. Through part time study, he obtained further graduate and post-graduate qualifications in Science and Environmental Management. He has led both public sector and private sector teams covering a range of disciplines from Town Planners, Civil Engineers and Environmental Scientists. Philip has worked for State and Local government, consulting firms and the mining sector.  Over the past twenty years, Philip has been involved in numerous construction projects including waste management facilities, marina developments, rail and road developments as well as industrial facilities.

Philip has been involved with numerous projects managing the design and monitoring of water quality, obtaining environmental and planning approvals for key projects within both Central and North Queensland, developing and implementing environmental management systems, and undertaking audits for industry and government.

Philip manages Catchment Solutions’ Reef Trust 4 and GBRF’s – Fitzroy Gully and Stream Bank Erosion Control Programs, both of which will prevent over 14,000 tonnes of fine sediment reaching the coastal waters of the Great Barrier Reef. Phil also leads numerous water quality monitoring and assessment projects for government and industry clients within Queensland, including the Department of Transport and Main Roads, North Queensland Bulk Ports Corporation and the Project Catalyst (funded by the Australia Government, Coke Cola and WWF).