The best way to minimise erosion is to reduce the amount of exposed earth surfaces on site. This can be achieved by phasing of earth works, covering up exposed earth areas with erosion control blankets of canvas covers, early reinstatement, paving etc. To reduce silt discharge from the remaining exposed earth areas, apply Best Practices as follows:
Erosion Control Blanket (ECB)
Silty water treatment system
Install effective final treatment facilities, such as silty water treatment plants
Ensure adequate holding capacity of the holding sump/pond for collection of silty water
Treat silty water collected immediately to ensure adequate storage is always available
Educate/supervise site works staff to maintain ECM at all time
Access weather forecast on NEA's website to take ECM actions before a rain event
Install online CCTVs and Total Suspended Solids (TSS) meters to monitor discharges at all times
Silt Fence & Cut-off Drain
Silt fence not properly embedded resulting in gaps below the fence & Silt fence installed on the wrong side. It should be installed to trap the silt from the worksite.
Silt fence firmly embedded in ground and installed in between cut-off drain and worksite.
Inadequate silt trap resulted in silty water discharges onto adjacent public place.
Silt trap properly designed with the usage of polymer block & geotextiles. (note: sand or granite chip as filter is not accepted)
Silty Water Treatment System