Soil erosion from construction sites causes major environmental problems for waterways and aquatic life. Sediments washed into waterways impact heavily on aquatic plants and animals and their habitat. Sedimentation also blocks stormwater drains, causing waterways to silt up and increasing the risk of flooding. A single building site can lose truckloads of soil in one storm!
Polluting stormwater is an offence that can result in on-the-spot fines and legal proceedings.
There are numerous benefits in adopting safe sediment and erosion control methods. These benefits can include:
- compliance with environmental regulations – in particular, the Protection of the Environment Operations Act 1997 – thereby reducing risk of fines;
- improved wet weather working conditions, reduced downtime and earlier building completion;
- fewer public complaints and a better public image for your business;
- reduced stockpile losses and clean-up costs;
- a healthier and safer environment for everyone.
Developers and builders have a legal obligation to take all reasonable care to prevent soil erosion and sediment loss from construction sites. This also applies to other trades people such as excavators & earthmovers, landscapers, concreters, painters & delivery drivers.
Supervisors need to ensure that workers under their control (e.g. sub-contractors) do not breach environmental laws.
Under the Protection of the Environment Operations Act 1997, prosecution and on-the-spot fines of up to $8000 apply to persons or businesses who allow soil or other pollutants to enter stormwater drains or waterways, or place materials in a position where this may occur.
Council regularly monitors construction sites to ensure that no environmental pollution is caused.
Councils have the power & responsibility to provide information to site builders/contactors & issue Clean-up Notices, Prevention Notices, Penalty Infringement Notices and Compliance Cost Notices.
There are numerous ways to reduce the risk of sediment leaving the site that you are working on. These can include the following:
- Establish a single stabilised entry point (e.g. blue metal/aggregate pad).
- Install geotextile sediment fence(s) along the low side of the site before work begins and straw bales embedded into the ground can also reduce flow velocity, filter sediments and reduce erosion.
- Divert uphill water around the building site with stabilised banks and channels and this is especially important on large, steep sites.
- Minimise the area to be cleared and leave as much vegetation as possible to filter runoff from the site.
- Stockpile topsoil, sand and other building materials behind the sediment controls, and never stockpile materials on the footpath or road reserve.
- Install appropriate waste receptacles on site (e.g. mini-skips, bins & wind-proof litter receptors).
- Provide a wash-down area behind sediment controls for washing and cleaning activities, brick cutting etc.
- Connect downpipes from the guttering to the stormwater drain as soon as possible.
- Fill in and compact trenches immediately after services have been laid.
- Stabilise and revegetate disturbed areas as soon as possible; turf strips are commonly used for this purpose particularly along the kerbside.
- Check erosion and sediment controls regularly, especially when rain is expected and directly after rain.
- Regularly sweep and collect material from the road and footpath, and never hose these areas.
Each site is different, and sediment and erosion control requirements need to be assessed on a site-by-site basis. An Erosion & Sediment Control Plan may be required with your Development Application (DA) to ensure that building materials and sediment are well maintained on site.
Control measures need to be installed before excavation or site disturbance. They need to be maintained in good working order & repair throughout the construction or development work and until 70% revegetation cover has been established.