Ministry of Water, Land and Air Protection - Talchako River - Groundwater Channel

Talchako River Groundwater Channel

Objectives

To restore access to existing offchannel habitat and restore groundwater off channel habitat in the Talchako River for overwinter and high flow refuge for Coho and Cutthroat.

FRBC Region/ MELP Region/ MoF Region

Vancouver Island/Cariboo/Vancouver Island

Author

Michael Parker , MELP

Proponent

International Forest Products, Mid Coast Division, Hagensborg, BC

Watershed

Talchako River

Location

Talchako River partially defines Tweedsmuir Provincial Parks’ South West boundary. It is located approximately 380 km West of the City of Williams Lake and 60 km East of the community of Bella Coola. Along with the Atnarko River it forms the Bella Coola River.

Introduction

All significant tributaries to the Talchako are glacial fed and limited to fish access by gradient within less than 1 km. The Talchako itself is highly glacial with very little offchannel habitat. Several offchannel ponds and groundwater channels exist between 72-84 km. As most of these run parallel to the mainstem on the valley floor, they were areas that were logged over. Beaver activity has also prevented access to several of these high value clear water areas.

Assessments and Prescriptions

In 1996 a Overview and Level 1 Assessment was completed for the Bella Coola River including the Talchako and some of its major tributaries. In 1998, further Level 1 Assessments were completed on several of the small groundwater channels and off channel habitat in the upper regions of the watershed.. Ministry of Environment completed prescriptions for SOD removal through old cutblocks, access structures around beaver dams and groundwater channel excavation to reopen and enhance areas within cutblocks.

Rehabilitation Work

On the ground activities can be divided into three:

SOD removal was carried out in three cutblock locations along small groundwater channels to improve flow and scour. These clearwater channels were full of past logging slash. Over 550 linear meters of channel was hand cleared at three different sites. Any material under 15 cm diameter and/or 2 meters in length was removed from the channels. All large material was left in place.
Groundwater channel excavation was carried out at one location during 1998. Roughly 200 meters of channel was excavated to redefine stream banks and establish deep pond areas in an area that had seen past impacts from skidding and other logging activities. This channel was typically excavated 2meters wide and 1 meter deep, with meanders, pools and pond areas. LWD was reestablished to the channel and ponds and keyed into the banks. As flows are stable through this groundwater area, no cable anchoring was employed.
A hand dug channel was established around a deserted beaver dam to gain access to nearly 1 km of groundwater channel and rearing pond area. The 20 meter long channel consisted of a series of step pools that dropped in total 0.8 meters. Each step was no more than 15 cm to ensure access of juvenile target species to the habitat upstream. The channel was lined with filter fabric and covered with an assortment of angular substrate. Rock / log structures created the plunge pools and were keyed to the banks for stability. Minimal riparian impact was created through the use of hand construction and a variety of local sedges, conifers and other vegetation transplanted to the edge of the channel. As the beaver dam itself created a high value pond habitat heavily complexed by mature LWD, it was a feature that should be maintained for a long period. Therefore, plastic was placed along the dam on the upstream side to ensure all water goes through the created side channel and would not percolate through the dam at lower flows. The plastic was then covered with soil and rock to hold it in place, and the whole dam covered with soils to promote vegetative growth, and establish the dam as a permanent feature. A small rip rapped overflow channel was created to handle any excessively high flows.

Cost Summary

Item	Cost
Machine	$22,200
Materials	$2,600
Labour	$110,000
Total	$134,800

Restoration Results

Within two hours of completing the beaver dam by pass channel one juvenile Coho and one Cutthroat were into the second step pool. By the next day fish were found throughout the steps. Minnow traps will be set in the pond and channel above in 1999 to examine distribution and species.

Removal of SOD created a visible increase in localized stream velocities and scour of fine in some areas was revealing buried cobble and gravel substrate.

Groundwater channel excavation was not completed at the time of writing this report.

Proposed Work

Further groundwater channel excavation and complexing is anticipated at three locations for 1999. Access problems at two long abandoned beaver dams will also be evaluated and prescriptions written.

For Further Information contact:

Michael A. Parker
Ministry of Environment and Parks
400-640 Borland St.
Williams Lake, BC
V2G 4T1
Tel.(250)398-4696
Fax.(250)398-4214

Niel Oborne
International Forest Products
P.O. Box 50
Hagensborg, BC
V0T 1H0
WRP Coordinator
Ph.982-3226

Initial hand excavation of beaver dam by pass channel, Talchako River, 77km.

Initial hand excavation of beaver dam by pass channel, Talchako River, 77km.

Same section of by pass channel with flow and vegetated banks, Talchako River 77km.

Portion of excavated groundwater channel at 77km, Talchako River prior to LWD complexing.