Ministry of Water, Land and Air Protection - Thearon Creek Bridge Site 518a Road

Thearon Creek Bridge Site 518A Road

Objectives

To replace a culvert which was acting as a barrier to fish migration.

FRBC Region/ MELP Region/ MoF Region

Cariboo-Chilcotin/Cariboo/Cariboo

Author

Ken MacKenzie

Proponent

Weldwood of Canada Ltd.

100 Mile House Operations

Location

The site is located at 2 km on the 518A Road. Thearon Creek flows into Eagle Creek just upstream from Murphy Lake.

Introduction

Rainbow trout are found throughout this system and other game fish species are found in Murphy Lake including burbot, lake trout and rocky mountain whitefish. A complete barrier to fish remains in place on the Ministry of Transportation and Highways road downstream from this site.

Assessments and Prescriptions

This site was identified as the 3^rd priority in the Eagle/Bradley fish passage-culvert inspection report. Water velocity in the culvert at the time of the assessments was 0.9 m/s with an outfall drop of 5 cm (fig 9-1).

Rehabilitation Work

Water was diverted around the channel during work (fig. 9-2).
Silt fences were installed downstream for the duration of the work.
An environmental monitor was on site for all phases of construction.

Structure Details

9 meter concrete deck bridge
pre-cast concrete footing and 8 inch steel towers
reconstructed stream channel 4 meters wide

Cost Summary

Bridge design, supply and install $40,000

Riprap, site plan and supervision $12,063

Total $52,063.

Environmental Benefits

An additional 9.9 km of habitat is now available to fish.

For Further Information Contact:

Ken MacKenzie
P.O. Box 97
Weldwood of Canada Ltd.
100 Mile House Operations
100 Mile House, BC
V0K 2E0
Tel. (250)395-8280

Figure 9-1. Culvert prior to replacement.

Figure 9-2 barrel to dissipate pumped water velocity.

Figure 9-3. Bridge superstructure across reconstructed channel.