• 26,576 smolts / 3400 adults (based on Tredger 1986/Ptolemy 2002 (high end)
• Conservation Concern Level @ 30% of capacity is 1,020 adults.

Existing Habitat:
watershed area (km2):	1226.8		Comments
mean annual discharge (m3/s):	55		Sediment problems - active slides, logging damage, periodic low summer flows, high temperatures and BOD impacts on lower river. Floodplain at Duncan and Lake Cowichan communities subject to flooding - major encroachment on flood plain - stream channelization impacts mainly chum salmon and rearing areas for other salmonids. Degraded habitat in tributaries above Cowichan Lake. Biomass 800-1000g/Unit at estimated steelhead carrying capacity.
Summer Base Flow (%mad):	15.7
accessible length (km):	33.7
productivity:	Very high

HABITAT RESTORATION TO DATE

• Seven DFO side channels constructed primarily for chum and coho salmon.
• Rule Curve for Norske Canada operation of the Lake Cowichan weir provides for improved conservation flows.

SPECIAL HABITAT PROTECTION REQUIREMENTS

• Provide adequate protection from urban expansion - especially on the flood plain.
• Ensure good logging practices on private land.
• Ensure flood protection works and other developments do not impact the lower river and estuary.
• Avoid more flow diversions unless storage is provided.

STEELHEAD OBJECTIVES AND STRATEGIES

• Increase wild stocks and maintain catch and release fishery over 25-km of fishable water.
• Review habitat productivity and current stock abundance in Cowichan Lake tributaries.
• Investigate potential stream restoration in areas of suitable gradients for steelhead.
• Work with DFO to minimize any impact on steelhead from early winter commercial chum fisheries.

IDENTIFIED RECOVERY OPTIONS

• Address sediment loadings from failing clay banks (eg. Stoltz Slide 27 km upstream) with an innovative revetment and stabilization program.

NOTES: Largely private forest lands. Vancouver Island Trout Hatchery at Duncan raises Cowichan steelhead on groundwater. Community hatchery involved in salmon production.

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Probably the single-most important steelhead habitat enhancement on the river has been securing a fairly reliable summer rearing flow downstream of Cowichan Lake. This was achieved under auspices of the Cowichan-Koksilah Water Management Plan (Ministry of Environment 1986), and included a field assessment of available trout habitat over a range of flows in the upper Cowichan River (Wightman and Ptolemy 1989). Water stored on the lake behind the Norske Canada weir is presently released according to an operational "rule curve" established between the licencee (Norske's Crofton pulp mill) and provincial Water Management Branch. This is essentially a water budgeting process intended to ensure an adequate water supply to the mill, while meeting fisheries, waste dilution and recreational requirements, whenever possible. The rule curve specifies a release of a minimum 7.08 cms (250 cfs) from the time storage behind the weir begins (usually in April-May) until September 15, after which an increase to 9.91 cms (350 cfs) is required to assist upstream migration of spawning chinook salmon. Extended droughts (such as occurred in 1998) can result in storage being exhausted and discharge to the river equaling natural inflows to the lake. This can result in discharge below the weir being substantially less than target levels.

In order to increase the reliability of meeting prescribed fisheries flows, DFO and MWLAP fisheries (through the Habitat Conservation Trust Fund) hired an engineering consulting firm to investigate rebuilding the weir and increasing storage on the lake (KPA Engineering Ltd. 1991). Results of this study indicated that an additional 0.57 m of weir height would add 36 million cubic metres of storage and guarantee prescribed fish conservation flows in 19 out of 20 years, on average. The estimated total construction cost in 1991 dollars was just over $300,000. While both fisheries agencies were initially supportive of this concept, organized opposition from lakeshore property owners (who threatened legal action to block weir construction), as well as anticipated shortfalls in capital costs for weir reconstruction, resulted in the project being indefinitely postponed. Now after more than 10 years have elapsed, the proposal should be revisited. This should include a review of the legal implications of seasonally flooding lakeshore properties where improvements (e.g., docks, wharves, sand beaches) may in fact be encroaching on land actually owned by TimberWest Forest Ltd., under the original E & N land grant (i.e., likely includes the lake bed and foreshore up to the average high water mark).

A second provincial initiative designed to improve Cowichan River fish habitat has focussed on stabilizing the "Stoltz Slide" clay banks, located about 27 km upstream of Cowichan Bay. With HCTF support, three engineering feasibility studies have been done to develop appropriate mitigation methods for this very large source of river sediments (Northwest Hydraulic Consultants Ltd. 1996; Newbury Hydraulics 1997; Willington 1998). To date, very little progress has been made, although there are now clearer options for stabilizing the site. These include rerouting surface water which now drains into a small basin behind the slide; opening side-channels on the river's south bank for flood relief; revegetating and revetting eroding gullies in the clay "faces"; removing willow thickets now encroaching into the river channel (i.e., increasing the channel's overall width); armoring the slide's "toe"; and installing three gradient control riffles to reduce water velocity and bank erosion. MWLAP regional staff will continue to discuss an implementation plan and budget for some of these measures with BC Parks, DFO and other key stakeholders (e.g., Cowichan Tribes, Cowichan Watershed Council, Steelhead Society of BC, etc.). It is hoped some tangible progress can be made in the next 1-2 years.

Other habitat improvements in the Cowichan watershed include seven side-channels built mainly by DFO, Cowichan Tribes or with the province through HCTF. While winter steelhead were not generally a target species in these developments, they should benefit when juveniles use them as winter refugia. Since many of DFO's channels are used extensively by spawning chum salmon, young steelhead should benefit from the availability of eggs and decaying carcasses prior to the onset of winter.

Provincial, federal and tribal biologists must work closely to ensure that side-channel designs reflect multi-species requirements, particularly given the present conservation status of wild coho and steelhead stocks on the Island's east coast.

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There are a myriad of habitat protection concerns for wild steelhead in the Cowichan River, but the most important continues to be logging on private land. This includes that owned by Weyerhaeuser Canada and TimberWest Forest Ltd., or small independent contractors who clear land for residential subdivisions or new commercial developments. Since there is little government regulation of logging practices on private land, fish habitat protection becomes the responsibility of the forest company or individual contractor. In the Cowichan Valley and elsewhere on Vancouver Island, the past "track record" in this regard has been generally poor. Regional MWLAP and district Ministry of Forests staff must undertake regular audits of logging practices on private land to ensure a "reasonable" level of habitat protection. A strong continuing "watchdog" role for public stewardship groups is also required. Further to this, continuing efforts by the provincial government to extend the Cowichan linear park corridor should be broadly supported as a visionary step in protecting this provincial "heritage river."

A second habitat concern is related to urbanization of the Cowichan Valley. Specifically this refers to the growth of Duncan, residential developments on the Cowichan River, and recreational properties on the south shore of Cowichan Lake. While the current British Columbia economic slowdown may have slowed growth for now, the longer term will likely see large increases in population with associated demands on natural resources like fish and water. It will take a concerted planning effort by all levels of governments to manage this growth, and ensure that other resources are sustainable. Provincial fisheries, water management and pollution prevention staff must monitor progress in achieving the recommendations of the Cowichan-Koksilah Water Management Plan, as a critical part of this growth management strategy.

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• 4000 smolts / 520 adults (based on Ptolemy 2002 SHA analysis)
• Conservation Concern Level @ 30% of habitat capacity is 156 adults

Existing Habitat:
watershed area (km2):	209		Comments
mean annual discharge (m3/s):	9.77		Sediment problems, logging damage, low summer flows - particularly in the lower reach. Baseflow alkalinity moderate at 45 mg/L and predicted capacity per steelhead size class is 245 g/Unit. Most of the productive parr habitat exists in the headwaters above Burnt Bridge.
Summer Base Flow (%mad):	4
accessible length (km):	36.8
productivity:	Moderate

HABITAT RESTORATION TO DATE:

• Marble Falls fishway by Fisheries and Oceans Canada

SPECIAL HABITAT PROTECTION REQUIREMENTS:

• Ensure good logging practices on private lands and properly deactivate unused roads
• Ensure flood protection works and development activities do not impact on lower river

STEELHEAD OBJECTIVES AND STRATEGIES

• Recover wild stocks to well within the Routine Management Zone capable of supporting a catch and release fishery over 5-km fishable water at long-term average of 600 angler days per annum.
• Provide more focus on this largely neglected system to address chronic problems arising out poor habitat protection on private forest lands and poaching.
• Conduct a complete biophysical assessment to document current habitat conditions and steelhead limiting factors.
• Develop a co-operative fisheries and habitat protection plan with the Cowichan First Nation for the Cowichan and lower Koksilah Rivers.
• Develop a full suite of restoration prescriptions using qualified consultants.

IDENTIFIED RECOVERY OPTIONS

• Reduce poaching
• Stream enrichment in upper reaches above Marble Falls

NOTES: Recovery prescriptions need to be developed - largely First Nation and private forestry lands. Limited public access. A community partnership involving both First Nation and other citizens could provide an important watchdog role and foster improved stewardship.

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A steelhead habitat capability study would be the preferred method of identifying potential restoration or enhancement projects in the Koksilah. However, if this is delayed due to funding limitations, MWLAP staff should consider stream fertilization as an interim habitat improvement measure. Based on snorkel observations, the upper river is likely phosphorus-limited during the late spring-summer growth period. Augmenting available dissolved phosphorus through fertilization should stimulate young steelhead growth and improve their survival to the smolt stage. Field sampling should be done to determine background water chemistry, seasonal flows, as well as juvenile steelhead life history and distribution, to prioritize stream reaches for fertilizer treatment. Inter-agency and public referrals are essential for gaining support and approval.

Other habitat restoration work would be best spent on deactivating logging roads, stabilizing gullies and revegetating landslides following extensive clearcutting on private land owned by TimberWest Forest Ltd. Fish habitat in the Koksilah has been severely degraded by these practices over many years. For now, a greater commitment to "upslope restoration" would likely be more cost-effective than actively pursuing new instream opportunities.

Several years ago, DFO installed a fishway at Marble Falls about 12 km upstream of the Cowichan River confluence. While the benefits of this structure to adult steelhead have not been evaluated, increased salmon distribution should help with nutrient replacement and provide juvenile steelhead with an important food source prior to winter (i.e., salmon eggs and carcasses). Easier steelhead passage above the falls should also help to reduce poaching losses at a natural migration "bottleneck."

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The single most important habitat protection issue for the Koksilah is logging on private forest land. As stated previously, there is little government regulation of logging practices on private land, so large companies and independent contractors are responsible for fish habitat protection. Consequently, MWLAP and Ministry of Forests staff should conduct regular audits of forest company and small landowner practices to ensure that basic fish habitat protection requirements are met. A strong "watchdog" role by public stewardship groups is also needed. This should help to promote better logging standards, which would be more consistent with those required by the FPC on Crown land.

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• 750 smolts / 98 adults (based on actual smolt counts)
• Conservation Concern Level is approximately 30 adults.

Existing Habitat:
watershed area (km2):	48.5		Comments
mean annual discharge (m3/s):	2.2		Major water diversion to Sooke reservoir is inactive and only used as backup. Limited watershed available to steelhead, low historic flows in summer. BC Park development below the Island highway has impacted steelhead rearing habitat. Most of the productive parr habitat exists upstream of Highway 1. Baseflow alkalinity moderate at 29 mg/L and predicted capacity per steelhead size class is 196 g/Unit. Capacity may be enhanced by thousands of chum carcasses. Due to short survey window to count adults, recent counts may be poor indicators of stock status. Adults move in and out of stream with short-term high flows that pose difficulties for standard snorkel counts.
Summer Base Flow (%mad):	10
accessible length (km):	4
productivity:	Moderate - High

HABITAT RESTORATION TO DATE

• Side- channel improvements undertaken.
• Rule Curve on dam operation provides for improved conservation flows in most years.

SPECIAL HABITAT PROTECTION REQUIREMENTS

• Avoid more flow diversions unless storage is increased.
• Maintain wetlands associated with Langford Lake to ensure sustained summer baseflows in a key tributary.
• Prevent any more encroachment in riparian zone.
• Complete LWD placements in Reach 1 below Finlayson Rd. bridge. LWD was removed by DFO in mid-1970s.

STEELHEAD OBJECTIVES AND STRATEGIES

• If stock is expirated, convert to hatchery status - 10,000 Cowichan smolts could be final-reared and released at Goldstream to create an angling opportunity.
• Clearly establish stock status to determine appropriate recovery strategy using all available techniques.

NOTES: Long-standing Amalgamated Conservation Society community hatchery involved in coho and chum enhancement. High visitor use park north of Victoria. Juvenile electrofishing done in 2001.

Report:

Construction of Artificial Fish Habitat in the Goldstream River, 2004. McCulloch (2005) (2.5MB PDF, opens new browser window)

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