Stream Bank Work Using a Turbidity Curtain, Sediment Bags and Straw Bale Sediment Traps Adjacent and Within the North Saskatchewan River.

BELGRAVIA OUTFALL

Location: Belgravia Outfall, on the North Saskatchewan River, City of Edmonton, Alberta

Client: City of Edmonton

Objective: Prevent sediment delivery into the North Saskatchewan River through the use of a turbidity curtain, silt fences, sediment bags and straw bale sediment traps.

In the fall of 2008, Terra Erosion Control implemented a vegetated riprap application in order to protect the newly constructed Belgravia Outfall and enhance fish habitat.

In order to comply with the Department of Fisheries and Ocean’s (DFO) regulations prohibiting activities resulting in sediment laden water entering fish habitat the following measures were implemented.

• A turbidity curtain was put into place in the river section facing the project site.
• Accumulated groundwater from the enclosed area of the outfall was pumped into silt / sediment bags located on the riverbank, within the confined area of the turbidity curtain.
• Water flowing from the silt / sediment bags was further filtered out into straw bale sediment traps.
• The disturbed riverbank area surrounding the outfall was enclosed using silt fences.

These measures were found effective at reducing sediment delivery into the North Saskatchewan River.  All sediment control measures were removed after completion of the work.

The sediment control portion of the Belgravia Stormwater outfall project demonstrated efficient ways of reducing sediment delivery into watercourses on construction project sites.