Archived - Miworth Bank Stabiilization Project - Riprap revetment

Miworth (BC)

Reasons for a Federal Assessment
Project Description
Final Decision

Reference Numbers

Canadian Environmental Assessment Registry: 09-01-49957
Fisheries and Oceans Canada: 09‑HPAC‑PA8‑00087

Environmental Assessment Type

Screening

Responsible or Regulated Authorities

Fisheries and Oceans Canada

Reasons for a Federal Assessment

On September 10, 2009, it was determined that an environmental assessment was required in relation to the project because Fisheries and Oceans Canada considered taking action in relation to subsection 35(2) of the Fisheries Act.

Project Description (as posted in the Notice of Commencement)

The Miworth Community Association proposes to construct a 185m length of river bank protection that riprap an area of natural river bank between two existing revetments. This reach of the Nechako River is on river right, an outside bend, and it was armoured in numerous sections over the last 3 years to reduce the effects of toe erosion and loss of property. At the location of proposed works, up to 12m of bank regression occurred. Proposed bank stabilization works are similar to what was used for existng revetments, which consist of a 'blanket' of riprap up to 2m thick placed at the toe of the bank and to the height of the existing upstream revetment, equivalent to the 100-200 year flood level. Trees with root wads will be incorporated into the riprap and granular soil and trees are placed on the bank slope above the riprap to create a stable bank angle and eventual green up. The scope of this project includes all elements of construction required to place riprap armor along approximately 185 metres of the Nechako River. These elements of construction include: removal of existing riparian vegetation along the top of bank for this 185 metre stretch of river bank; construction of an access road within the proposed riprap footprint, to facilitate transport of riprap armor down the face of the river bank; excavation of parent material from under the proposed riprap footprint; placement of riprap armor and large woody debris along the river bank; and lastly, re-planting of vegetation along the face and top of bank.

Final Decision

A decision was taken on November 12, 2009 and was that the authority may exercise any power or perform any duty or function with respect to the project because, after taking into consideration the screening report and taking into account the implementation of appropriate mitigation measures, the authority is of the opinion that the project is not likely to cause significant adverse environmental effects.