Stormwater Management

Runoff control from roads and highways is necessary to reduce impacts on adjacent drainage and vegetation systems. Erosion controls at source are considered critical. Assessment of the receiving environment is a key component to manage stormwater from roads and infrastructure. Final landscaping and revegetation is important for long-term control of erosion and runoff.

Issues related to runoff and erosion that may arise include changes in benthic substrate, reduction in light penetration in waterways, release of nutrients and toxic chemicals, siltation of native vegetation, farm dams and water supplies.

Millin EMS has been involved in local road network and large scale highway construction projects. Project components have included layout of erosion and sediment controls, monitoring of construction works and provision of environmental advice. Works include review of drainage designs, concept layouts for open drainage swales, retention basins, sedimentation basins and wetlands for longer term storm water control. Construction Environmental Management Plans were prepared for a number of larger projects.

Mitigation options include erosion control at source through geofabrics and matting, stormwater diversion, sedimentation control and rehabilitation within drainage systems, installation of swales, flow retardation structures, retention basins, wetlands and gross pollutant traps.