Storm Water remediation
Storm water remediation workshop and tour for council staff
Capacity to Deliver - LP013-008
The issue
High velocity storm water runoff from hardened surfaces such as house roofs and roads can increase erosion and sediment transport, impacting sensitive and endangered swamp systems and drinking water catchments.
In addition, suburban runoff introduces high levels of nutrients and fecal coliforms into natural waterways and drinking supplies which can cause blue / green algae blooms and increased costs in drinking water treatment.
Swamps offer significant ecosystem services, helping regulate and filter water flows to downstream creeks and rivers, and are threatened from a number of different sources.
Browns swamp, Clarence, a critically endangered Newnes Plateau Shrub Swamp situated high in the Sydney drinking water catchment, is under threat from urban stormwater.
The solution
Lithgow Oberon Landcare, Central Tablelands Local Land Services and Lithgow City Council saw an opportunity to carry out important storm water remediation works to protect threatened swamps, run a workshop for Lithgow City Council staff on soft engineering solutions with local contractors and bring staff from several councils together to learn from each other and experienced field based contractors.
Utilising funding from the Central Tablelands Local Land Services Swamped by Threats project, staff from several departments of Lithgow City and Mid-West Councils attended a workshop demonstrating storm water remediation techniques and undertook a tour of remediation sites in the Blue Mountains City Council Local Government Area.
The impact
Staff had the opportunity to watch contractors building a rock lined channel, visit biofilters and ask questions of designers, practitioners and staff who monitor waterway health.
They learnt the value of slowing water velocity using carefully placed stone and plunge ponds, storing water in the landscape using permeable materials and techniques and incorporating vegetated biofilters to remove dissolved nutrients.
Additionally, they had the opportunity to discuss funding options and the value of utilising in-house capacity.
Improving Local government capacity to reduce storm water impacts through their roadside management can significantly improve waterway health for riparian ecosystems and drinking water quality. Moreover, storing water in the landscape, rather than removing it downstream, can contribute towards drought resilience.
Key facts
- Storm water threatens critically endangered Newnes Plateau Shrub Swamps and other riparian ecosystems.
- Staff from two councils learnt about soft engineering solutions to storm water treatment from council colleagues.
- Naturalised storm water outlets allow water to be stored in the landscape, improve biodiversity and reduce impacts of high velocity storm water.