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McNab Creek Spawning/Rearing Channel ProjectFinal Monitoring Report (2009)

August 2009

Prepared for:

Howe Sound Pulp and Paper Limited PartnershipPort Mellon, British Columbia

Suite 201 – 1571 Bellevue Ave., West Vancouver, BC, Canada V7V 1A6 • Tel: 1.604.926.3261 Fax: 1.604.926.5389 • www.hatfieldgroup.com

MCNAB CREEK SPAWNING/REARING CHANNEL PROJECT

FINAL MONITORING REPORT (2009)

Prepared for:

HOWE SOUND PULP AND PAPER LIMITED PARTNERSHIP

PORT MELLON, BC V0N 2S0

Prepared by:

HATFIELD CONSULTANTS SUITE 201 – 1571 BELLEVUE AVENUE

WEST VANCOUVER, BC V7V 1A6

AUGUST 2009

HS1104

TABLE OF CONTENTS

LIST OF TABLES .......................................................................................... ii LIST OF FIGURES ......................................................................................... ii

1.0 INTRODUCTION .................................................................................. 1

2.0 METHODS ........................................................................................... 4

3.0 RESULTS AND DISCUSSION ............................................................. 5

3.1 CHANNEL SLOPE AND RIPARIAN VEGETATION ................................................ 5 3.2 HABITAT ................................................................................................................ 10 3.3 ACCESS-ROAD CULVERT ................................................................................... 13 3.4 FISH PRESENCE ................................................................................................... 13 3.4.1 Fry .................................................................................................................... 13 3.4.2 Adult Fish .......................................................................................................... 17 3.5 WATER QUALITY .................................................................................................. 18 3.6 OLD SPAWNING/REARING CHANNEL ............................................................... 20

4.0 SUMMARY ......................................................................................... 21

5.0 CONCLUSIONS AND RECOMMENDATIONS .................................. 24

6.0 BIBLIOGRAPHY ................................................................................ 25

7.0 CLOSURE .......................................................................................... 26

McNab Creek 2008/2009 Final Monitoring Report – Final i Hatfield

LIST OF TABLES

Table 1 Summary of cover habitat values used for the McNab Creek spawning/rearing channel assessment (RISC 1999). ................................. 10

Table 2 Results of fishing effort at the McNab Creek spawning/rearing channel. ...................................................................................................... 14

Table 3 Observations of adult salmon in McNab Creek spawning/rearing channel, November 13, 2008. ..................................................................... 17

Table 4 Results of water quality measurements for the McNab Creek spawning/rearing channel. .......................................................................... 19

Table 5 Salmonid and small fish usage by reach of the McNab Creek spawning channel from 2004 to 2009. (“Lower” is the old channel; “middle” is Reach 1; “upper” is Reach 2.) ................................................... 22

Table 6 Adult returns observed for the last six reporting years. .............................. 22

LIST OF FIGURES

Figure 1 Location of McNab Creek spawning/rearing channel. .................................. 3

Figure 2 Steep slopes on upper Reach 2 of the McNab Creek spawning channel, as observed August 2009. ............................................................. 5

Figure 3 Bank erosion observed in the middle section of Reach 1 of the McNab Creek spawning channel, August 2009. ........................................... 6

Figure 4 Middle area of Reach 1 of the McNab Creek spawning channel in October 2005 showing very sparse vegetation on banks. ............................ 7

Figure 5 Reach 1 riparian vegetation in the middle McNab Creek spawning channel area as of August 2009. .................................................................. 7

Figure 6 Reach 2 upper channel area of the McNab Creek spawning channel illustrating very sparse vegetation in November 2005. ................... 8

Figure 7 Reach 2 vegetation plot in the upper McNab Creek spawning channel illustrating sparse growth as of August 2009. ................................. 8

Figure 8 Bench areas along steep slopes of McNab Creek spawning channel provide some foothold for plants, 13 November 2008. ................... 9

McNab Creek 2008/2009 Final Monitoring Report – Final ii Hatfield

Figure 9 Riparian vegetation in lower Reach 1 of McNab Creek spawning channel; substrate is primarily silt and sand due to low gradient (August 2009). ............................................................................................ 10

Figure 10 Upper section of Reach 1 of McNab Creek spawning/rearing channel illustrating cover habitat and substrate (August 2009). ................. 11

Figure 11 Middle of Reach 2 of McNab Creek spawning/rearing channel - habitat and substrate composition; August 2009. ....................................... 12

Figure 12 Green algae in Reach 1 rearing pools, McNab Creek spawning channel; April 2009. .................................................................................... 13

Figure 13 Rainbow trout/steelhead parr captured in the lower reach of the McNab Creek spawning channel; April 2009. ............................................. 16

Figure 14 Coho salmon fry captured at McNab Creek spawning/rearing channel in April 2009. ................................................................................. 17

Figure 15 Adult chum salmon captured from the new extension of the McNab Creek spawning channel, November 2008. ................................... 18

Figure 16 Riparian vegetation along old section of the McNab Creek spawning/ rearing channel, August 19, 2009. ............................................. 20

Figure 17 Invertebrate larvae found on a rock in the new channel, November 2008. ........................................................................................................... 23

Figure 18 Caterpillar from the middle reach found on shoreline rocks during the November 2008 visit. ............................................................................ 23

McNab Creek 2008/2009 Final Monitoring Report – Final iii Hatfield

McNab Creek 2008/2009 Final Monitoring Report – Final 1 Hatfield

1.0 INTRODUCTION

Hatfield Consultants (Hatfield) was retained by Howe Sound Pulp and Paper Limited Partnership (HSLP) to conduct a six-year (2003/4 to 2008/9) monitoring program of the McNab Creek spawning and rearing channel extension. The channel was built as part of a compensation program for annual maintenance dredging at the HSLP Rainy River water intake. In this regard, HSLP has contributed substantially to the completion of the channel extension. Under the Fisheries Act Section 35(2) Authorization (No. 01-HPAC-PA3-000-000935) issued for the dredging works by Fisheries and Oceans Canada (DFO), HSLP is obliged to carry out the monitoring program to evaluate the success of the channel extension.

This final monitoring report provides details on the approach and methods used by Hatfield to complete the monitoring activities as specified in the Authorization for the 6-year monitoring program, and summarizes the results obtained.

The channel extension was primarily designed and constructed by DFO from 2001 to 2003, and was connected to an existing compensation channel that was built in the 1990s. The channel is approximately 900 m long, 10 m wide, and was completed prior to the 2003 salmon-spawning season. The channel runs parallel to McNab Creek, and is groundwater-fed; no surface water from McNab creek flows directly into the compensation channel.

In 2004, HSLP sold the land through which the compensation channel flows to A.J.B. Investments Ltd. (AJB). In 2006, AJB sold the McNab Creek land to Columbia National Investments Ltd. These land transfers do not alter HSLP’s obligations under the Section 35(2) Authorization; however, it does mean that access to the site for channel monitoring must be approved by the current owners.

The three field data collection site visits covered under this report were carried out in November 2008, and April and August of 2009. In general, these sampling times are consistent with previous sampling cycles. Data collection activities during each site visit included a fish presence evaluation, vegetation, and water quality assessment to determine if the channel was functioning successfully as fish habitat. A visual slope stability assessment and photographic documentation showing habitat values of the spawning/rearing channel were also carried out. Sampling objectives for each site visit, which varied seasonally, are outlined below:

Site Visit No. 16 (November 2008): The site visit was intended to coincide with salmon spawning activities in the channel and also involved efforts to confirm the presence/absence of juvenile fish in the channel at this time;

Site Visit No. 17 (April 2009): The purpose of this visit was to assess the channel during the spring period. The assessment included the presence/absence of juvenile fish, water quality and slope stability, and the growth of riparian vegetation; and

Site Visit No. 18 (August 2009): This site visit included the assessment of juvenile fish presence/absence, water quality and slope stability/ vegetation, as well as visual counts of any early adult fish.

McNab Creek is located along the northwestern shore of Howe Sound, approximately 8 km northeast of the HSLP mill. The spawning/rearing channel itself is positioned approximately 400 m southeast of McNab Creek, and drains into Thornbrough Channel of Howe Sound. An overview of the McNab Creek study area is illustrated in.Figure 1


Figure 1 Location of McNab Creek spawning/rearing channel.


2.0 METHODS

The primary objective of the ongoing monitoring program is to determine whether the channel habitat is functioning as intended by assessing a range of physical and biological indicators. The compensatory habitat is deemed to be functioning as intended if, in the opinion of DFO, the habitat is physically stable and available for fish to utilize.

The methods being used for assessing the McNab Creek channel generally follow those outlined in the Resource Information Standards Committee (RISC) Fish and Fish Habitat Inventory Standards and Procedures (RISC 1999 and 2001), and the BC Ministry of Environment, Lands and Parks - MELP guidelines Fish and Fish Habitat Procedures, Technical Circular No. 8 (Johnston and Slaney 1996). A brief outline of the monitoring methods is provided below.

Specific methods used to monitor the McNab Creek spawning/rearing channel during the 2008-2009 cycle consisted of five main components:

1. Photographic documentation and assessment of the compensatory habitat – Photographs showing condition of riparian vegetation, habitat values and conditions, and physical stability of the channel were taken with a digital camera. Digital photographs from each site visit were retained for comparative purposes.

2. Riparian vegetation survey – The vegetation survey involved a visual assessment of planted and natural riparian vegetation in two twenty meter square plots that were established in the first and second reaches of the new channel. Photo surveys were conducted for several years at these plots.

3. Water quality monitoring – The water quality assessment was conducted primarily using a YSI 85 water quality meter; coordinates of the water quality stations were recorded using a Garmin 76 global positioning system (GPS). Parameters measured included temperature (°C), specific conductivity (µS/cm), and dissolved oxygen (mg/L) and pH.

4. Habitat survey – Habitat types (cover, rearing, and spawning), instream vegetation, and stream morphology were assessed visually using MELP and RISC guidelines. Bank gradient was recorded using a Suunto clinometer; channel widths and lengths were measured using a tape measure. The physical stability of the channel habitat and channel banks were also assessed visually and documented with a digital camera; areas of erosion were noted and recorded relative to their location within the channel reach.

5. Fish survey – The presence of fish in McNab Creek spawning/rearing channel was determined using visual observations and Gee-type minnow trapping techniques. Adult fish presence was assessed by visual observation, which included spawning activities, possible redd locations and salmon carcasses. The coordinates and location of any redds and observed spawning activities were documented using the GPS. All fish


captured during the trapping activities were measured for fork length to the nearest mm using a standard fish measuring board, and weighed to the nearest 0.01 g using a digital balance. Efforts were also made during the survey work to determine the presence/absence of aquatic invertebrates in the stream channel by examining submerged portions of cobble and boulder substrate throughout the new section of the channel.

3.0 RESULTS AND DISCUSSION

The field data collection activities at the McNab compensation channel presented in the 2009 final monitoring report were carried out during three site visits on November 13, 2008, April 16, 2009, and August 19, 2009. Results from previous site visits are reported in Hatfield 2004, 2005, 2006, 2007 and 2008 and summarized herein.

The new channel extension consists of two reaches, which were defined based on changes in slope, substrate characteristics, and channel morphology. Reach 1 extends upstream from the McNab Creek access road culvert for approximately 500 m. Reach 2 continues from the top of Reach 1 for approximately 400 m to the upstream end of the spawning/rearing channel.

3.1 CHANNEL SLOPE AND RIPARIAN VEGETATION

The spawning/rearing channel was excavated down to approximately 6 m below grade in some places to access sufficient groundwater flow. As a result, the banks of the channel were uniformly steep at an approximate maximum gradient slope of 50° (Figure 2).

Figure 2 Steep slopes on upper Reach 2 of the McNab Creek spawning channel, as observed August 2009.


Slope erosion was observed in 2004, mostly in Reach 2, likely due to heavy winter rainfall events. From 2005, no major changes with respect to slope stability in the new channel reaches have been reported during annual monitoring programs. Figure 3 illustrates an eroded slope that appears to be stabilizing.

Figure 3 An eroded bank observed in the middle section of Reach 1 of the McNab Creek spawning channel, August 2009.

To date, relatively sparse riparian vegetation has been established on the steep banks of the new channel (Figure 2 and Figure 3). To assess the establishment of riparian vegetation, two study plots were set up on the slopes of Reach 1 and Reach 2 of the new channel. Figure 4 and Figure 5 show vegetation establishment in Reach 1 (middle reach) where some vegetation has managed to take hold (2004 compared to 2009). Figure 6 and Figure 7 show areas of the upper channel in Reach 2 (upper reach) where only sparse vegetation growth has occurred over the 6-year period. Quantitative assessment of riparian vegetation using the established plots was not conducted as part of the monitoring program given the steep slopes of the spawning channel.


Figure 4 Middle area of Reach 1 of the McNab Creek spawning channel in October 2005 showing very sparse vegetation on banks.

Figure 5 Reach 1 riparian vegetation in the middle McNab Creek spawning channel area as of August 2009.


Figure 6 Reach 2 upper channel area of the McNab Creek spawning channel illustrating very sparse vegetation in November 2005.

Figure 7 Reach 2 vegetation plot in the upper McNab Creek spawning channel illustrating sparse growth as of August 2009.


Natural vegetation is present in areas along the top-of bank on both sides of the channel, including ferns, salmonberry (Rubus spectabilis), various grasses, foxglove (Digitalis purpurea), and Scotch broom (Cytisus scoparius). This vegetation is becoming established along the channel slopes, as observed in the following figures, where topsoil has remained following channel construction activities. Red alder (Alnus rubra), Douglas fir (Pseudotsuga menziesii), Western Red Cedar (Thuja Plicata) and Western Hemlock (Tsuga Heterophylla) trees are also finding a foothold along the steep slopes.

Riparian vegetation has increased over the years, particularly during the 2008-2009 monitoring period. It has been observed that where benches have developed, vegetation can get a foothold and provide slope stability (Figure 8). Riparian vegetation acts to stabilize channel slopes by binding soil in place, and provides cover habitat to rearing fry. Given the system is primarily groundwater fed, erosion of stream banks may be less of an issue than in systems influenced primarily by surface water flows.

Figure 8 Bench areas along steep slopes of McNab Creek spawning channel provide some foothold for plants, 13 November 2008.

Riparian vegetation has successfully established itself on the banks of the lower Reach 1 area of McNab Creek upstream of the culvert. Figure 9 illustrates dense shrub growth as of August 2009.


Figure 9 Riparian vegetation in lower Reach 1 of McNab Creek spawning channel; substrate is primarily silt and sand due to low gradient (August 2009).

3.2 HABITAT

The McNab Creek spawning/rearing channel was originally assessed for a number of habitat features including: morphology, cover habitat, current velocity, substrate characteristics, and gradient during the first three site visits presented in the 2004 annual report. Table 1 summarizes values used for assessing the amount of cover habitat present in the channel.

Table 1 Summary of cover habitat values used for the McNab Creek spawning/rearing channel assessment (RISC 1999).

Habitat Value/Amount Definition

Cover (boulder, deep pool)

None No cover exists at the site

Trace Cover exists over <5% of the site

Moderate Cover exists over 5-20% of the site

Abundant Cover exists over more than 20% of the site

Functioning large woody debris

None No woody debris structures present in stream

Few < 1 piece per channel width

Abundant > or = 1 piece per channel width


The amount and type of cover habitat in both reaches of the spawning/rearing channel has remained essentially unchanged. Since the channel is groundwater-fed, disturbance of habitat features (i.e., boulders, large woody debris, etc.) is unlikely, with no signs of bed scour. A range of cover habitat types is available in both reaches of the new channel section, potentially providing rearing, overwintering, and spawning areas for salmonids.

Reach 1 is characterized by sections of slow moving water, low gradient, fairly uniform stream morphology (a few riffle-pool complexes), moderate cover habitat consisting mostly of boulder and low shrub cover, and an abundance of functioning large woody debris placed in the channel following excavation (Figure 9). The lower half of the reach has a predominantly silt and sand substrate while cobble and gravel are more prevalent in the upper section.

A few sections of riffle-pool channel morphology were also noted in Reach 1. There was a trace amount (<5%) of deep pools but no undercut banks observed. Deep pools and undercut banks act to provide cover habitat to both rearing and spawning fish. The deposition of fine substrate material continues in much of Reach 1; the low gradient and flows in this part of the channel generally limit the removal of this fine material.

Channel gradient in upper Reach 1 increases upstream, and shrub cover and silty sediments are found less frequently. Figure 10 shows tree stump cover with a small amount of riparian vegetation. The dominant bed material is cobble, and algal growth is present on rocks.

Figure 10 Upper section of Reach 1 of McNab Creek spawning/rearing channel illustrating cover habitat and substrate (August 2009).


Channel gradient in Reach 2 is slightly greater than that of Reach 1. This results in faster water velocities and an increase in riffle-pool type morphology. Compared to Reach 1, Reach 2 exhibits a more complex channel substrate and includes an even mix of gravels, cobbles, and boulders. Boulders represent approximately 20% of the cover habitat in Reach 2. A moderate amount of deep pools (5-20%) were observed in this reach and the amount of functioning large woody debris in Reach 2 was comparable to Reach 1 (> 1 piece per channel width). Figure 11 illustrates the dominant substrate type (cobble and gravel) observed in the upper section of Reach 2.

Figure 11 Middle of Reach 2 of McNab Creek spawning/rearing channel - habitat and substrate composition; August 2009.

Filamentous algae has been observed on multiple occasions during the monitoring surveys, typically in the slower water velocity sections of Reach 1 (Figure 12) as well as, but less frequently, in the faster water of Reach 2. The amount of algae did not appear to be excessive during any of the site visits and is not expected to negatively affect water quality (i.e., result in lower dissolved oxygen levels) or other habitat features in the channel.


Figure 12 Green algae in Reach 1 rearing pools, McNab Creek spawning channel; April 2009.

3.3 ACCESS-ROAD CULVERT

At the downstream end of the new channel, a half-arch culvert was installed underneath the McNab Creek access road connecting the new section to the older channel. The culvert appears to be stable with a good mix of substrate materials (gravels and cobble material) on the channel bottom. The potential for the culvert to become blocked by the downstream movement of debris does not appear to be significant at this point, even during large rain events, as the channel is groundwater fed and the culvert is sized appropriately. Regardless, seasonal maintenance should be carried out to check for blockages at the upstream end of the culvert.

3.4 FISH PRESENCE

3.4.1 Fry

During the November 2008 to August 2009 site visits to the McNab Creek spawning/rearing channel, minnow trapping and visual observations were used to determine the degree of utilization by fish of the channel. Required fish collection permits were obtained from the BC Ministry of Environment and


Fisheries and Oceans Canada prior to carrying out the fish sampling activities. Copies of the permits can be provided on request.

Minnow traps were set at various locations throughout the channel and left to soak for approximately 5 hours during each of the one-day site visits. Nine to eleven minnow traps were set in each area (lower, middle and upper reaches) on each visit. Table 2 lists the fork lengths and weights of fish captured during the 2008-2009 McNab Creek spawning/rearing channel assessment.

Table 2 Results of fishing effort at the McNab Creek spawning/rearing channel.

Channel Reach

November 13, 2008 April 16, 2009 August 19, 2009

Species Fork Length (mm)

Weight (g)


Weight (g)


Weight (g)

Old Channel Below Culvert

Steelhead 159 23.17 Stlhd/Rb1 120 18.0 Coho 81 5.06 Coho 76 5.35 Coho 89 8.02 Sculpin 104 12.18 Coho 67 2.84 Coho 83 7.44 Coho 80 4.76 Coho 72 3.81 Coho 71 3.52 Coho 67 2.80 Coho 66 2.91 Coho 74 4.51 Coho 67 3.12 - - -

Steelhead 52 1.10 - - - Coho 54 2.40 - - -

New Channel Reach 1

Coho 71 3.36 Coho 74 4.98 Coho 81 5.35 Coho 66 3.46 Coho 96 8.46 Coho 65 4.35

Steelhead 123 18.08 Coho 72 4.05 Coho 55 2.31 Coho 74 4.42 Coho 79 5.66 Coho 65 3.02 Coho 67 3.37 Coho 82 5.58 Coho 59 2.43 Coho 71 3.75 Coho 76 4.26 Coho 61 2.42 Coho 61 2.12 Coho 82 6.12 Coho 65 2.81 Coho 66 2.65 Coho 84 5.95 Coho 56 2.16 Coho 64 2.77 Coho 66 3.06 Coho 62 2.41 Coho 65 2.79 Coho 67 3.38 Coho 79 5.22 Coho 62 2.54 Stlhd/Rb1 54 1.64 Coho 59 2.09 Coho 64 2.48 - - - Coho 60 2.06 Coho 62 2.11 - - - Coho 63 2.59 Coho 63 2.33 - - - Coho 55 2.05 Coho 68 3.21 - - - Coho 71 3.81 Coho 74 3.83 - - - Coho 65 2.80 Coho 63 2.30 - - - Coho 60 1.99

- - - - - - Coho 64 2.63 - - - - - - Coho 67 3.32 - - - - - - Coho 57 1.66 - - - - - - Coho 59 1.59 - - - - - - Coho 58 2.10 - - - - - - Coho 58 1.99 - - - - - - Coho 61 2.16 - - - - - - Coho 58 2.14 - - - - - - Coho 61 2.14


Table 2 (Cont’d.)

Channel Reach

November 13, 2008 April 16, 2009 August 19, 2009


Weight (g)


Weight (g)


Weight (g)

New Channel Reach 2

Coho 62 2.62 Coho 77 6.6 Cutthroat 165 49.75

Steelhead 74 3.53 Coho 83 7.33 Cutthroat 132 21.72

Coho 62 2.89 Coho 69 3.46 Cutthroat 109 12.77

Coho 62 2.73 - - - Cutthroat 114 13.79

Coho 64 2.6 - - - Sculpin 94 10.59

Steelhead 74 3.67 - - - Sculpin 95 9.01

Coho 57 1.62 - - - Cutthroat 100 9.43

Coho 65 2.47 - - - Cutthroat 88 6.69

Coho 72 3.98 - - - Coho 84 6.23

Coho 68 3.68 - - - Cutthroat 77 4.51

Coho 62 3.69 - - - Coho 56 1.96

Coho 67 2.95 - - - Coho 57 1.78

Coho 71 3.75 - - - Coho 56 1.82

Coho 69 2.71 - - - Coho 63 2.45

Coho 76 4.47 - - - Coho 58 1.84

- - - - - - Coho 55 1.91

- - - - - - Coho 57 1.92

NFC = No fish captured. 1 Steelhead/Rainbow parr.

Minnow traps were set downstream of the culvert/access road in the Old Channel. Coho salmon fry (Oncorhynchus kisutch) were the predominant fish fry captured, which included 13 Coho, 2 steelhead (Oncorhynchus mykiss) and 1 steelhead/rainbow trout fry. Coho fork lengths ranged from 54 to 89 mm; weights ranged from 2.40 to 8.02 g. Two steelhead were captured in November 2008 (52 and 159 mm long); one steelhead/rainbow trout parr was collected in April 2009 (123 mm) (Figure 13); one sculpin was captured in August 2009 (104 mm).


Figure 13 Rainbow trout/steelhead parr captured in the lower reach of the McNab Creek spawning channel; April 2009.

Minnow traps set in the middle reach (Reach 1) during each of three site visits in 2008-2009 produced a total of 52 coho salmon fry ranging in length from 55 to 96 mm, and weighing from 1.59 to 8.46 g. One steelhead (123 mm long) and one steelhead/rainbow trout fry (54 mm) were also captured in the middle reach during this reporting period.

In the upper section of the new channel extension (Reach 2), 24 coho salmon fry were caught during 2008-2009. These ranged in length from 55 to 84 mm and in weight from 1.78 to 7.33 g. Two steelhead were captured in November 2008 – both were 74 mm long. Cutthroat trout were found in the upper reach during August 2009; seven fry ranged from 77 to 165 mm in length and 4.51 to 49.75 g in weight. Two sculpins were also captured in the upper reach in August 2009. Figure 14 shows a coho salmon captured in Reach 2 during the April 2009 site visit.


Figure 14 Coho salmon fry captured at McNab Creek spawning/rearing channel in April 2009.

Fish were also visually observed throughout the new channel; however, it was difficult to quantify their numbers. The presence of fish in all parts of the new channel is encouraging and this indicates that fish are successfully utilizing the entire length of the new channel extension. In general, this suggests the presence of sufficient food and cover in the channel for fish to survive and grow.

3.4.2 Adult Fish

There were several redds observed by the field crew during the November 2008 site survey. Data presented in Table 3 indicate that a total of 20 adult chum salmon were present in the channel at the time of the survey. Three salmon carcasses were present on this trip and one fish was captured for photographs (Figure 15).

Table 3 Observations of adult salmon in McNab Creek spawning/rearing channel, November 13, 2008.

Species Old Channel Reach New Channel Reach 1 New Channel Reach 2 Total # of live fish (Chum salmon) 0 6 14

Total # of carcasses 3 0 0


Figure 15 Adult chum salmon captured from the new extension of the McNab Creek spawning channel, November 2008.

3.5 WATER QUALITY

Water quality was measured at three stations along the McNab Creek spawning/rearing channel on all three site visits. Station 1 was located immediately downstream of the access road culvert in the lower section of the channel; station 2 was located at the Reach 1/Reach 2 reach break; station 3 was located at the headwaters of the channel. UTM coordinates were recorded for the three sampling sites using a GPS.

Table 4 summarizes water quality results for the McNab Creek spawning/rearing channel for all three site visits during 2008-2009. These data are compared to results from previous monitoring programs at the channel (Hatfield 2004, 2005, 2006, 2007 and 2008).


Table 4 Results of water quality measurements for the McNab Creek spawning/rearing channel.

Site UTM Coordinates

(August 2009) Parameter

Results

Nov. 13, 2008 April 16, 2009 Aug. 19, 2009

Station 1 Reach 1 Zone: 10 E: 471807 N: 5490177

Temperature °C 8.5 7.6 8.9 pH 6.02 6.07 6.16

Conductivity (µS/cm) 9.0 15.0 16

Dissolved Oxygen 10.6 mg/L 10.4 mg/L 9.4 mg/L


Temperature °C 8.5 7.1 9.1 pH 5.89 6.03 6.09




Temperature °C 9.7 6.7 10.0 pH 5.97 6.00 6.05



Water temperatures ranged from a low of 6.7°C recorded at Station 3 during the April 2009 site visit, to a high of 10.0°C observed at Station 3 during the August 2009 visit. This is consistent with measurements taken during the previous 5 years; the highest temperature recorded was 15.5°C in 2004. Results for the six-year monitoring program were well within the provincial water quality guidelines for rearing salmon (<17°C) and trout (<19°C) (Government of BC 2001).

pH values exhibited considerable similarity during the three site visits in 2008-2009 with values slightly higher in August 2009 relative to November 2008. The values ranged from 5.89 at Station 2 in November 2008 to 6.16 at Station 1 in August 2009. All pH values recorded during the three field visits were below the provincial and federal water quality guidelines for the protection of aquatic life (6.5 to 9) (Government of BC 2001, CCME 2003). It is unknown why pH values continue to be low this monitoring year and during 2007-2008. pH values from 2004 to 2007 ranged from 5.0 to 7.6, indicating some values were within the range provided by the guidelines. It does appear that groundwater pH values can be low in this area as HSLP personnel have reported pH values in the range of 5.8 to 8.3 near the mill (S. Sim, HSLP, pers. comm. 2004).

Conductivity values were fairly consistent within and across sites during the three site visits. Values ranged from 6.0 to 16 μS/cm. These low values are typical of other streams in the general area and streams with low pH. Previous monitoring programs reported conductivity levels ranging from 11.5 to 60 μS/cm.


Dissolved oxygen levels were high (>10 mg/L) at all stations during November 2008 and April 2009 site visits; August 2009 dissolved oxygen levels were slightly lower, ranging from 8.8 to 9.4 mg/L. Over the six-year monitoring period, dissolved oxygen levels ranged from 7.44 mg/L (2004) to 13.0 mg/L (Nov 2008). The channel likely remains well oxygenated during spawning and when rearing salmon are present in the system.

Although the channel is primarily groundwater fed and largely independent of weather conditions, it does experience some degree of seasonal fluctuation. Therefore, unless changes occur in ground water discharge, it is not likely that the water level will drop below a threshold level year-round. The lowest water levels observed in the channel over the past three monitoring cycles occurred during the August 2009 site visit.

3.6 OLD SPAWNING/REARING CHANNEL

For comparative purposes, the field surveys also included a qualitative assessment of the older channel, which connects the new channel with the intertidal foreshore. The riparian vegetation along both banks of the older channel is well established with a diverse mix of native tree, shrub, and grass species (Figure 16). Habitat characteristics in the older section of the channel include functioning large woody debris and a varied substrate with a mix of gravels, cobbles and boulders. Rearing, spawning, and cover habitat was noted to be abundant and stable.

Figure 16 Riparian vegetation along old section of the McNab Creek spawning/ rearing channel, August 19, 2009.


4.0 SUMMARY

Overall, the new section of the McNab Creek spawning/rearing compensation channel is functional in terms of fish utilization, water quality, and slope stability. The riparian vegetation is developing on both banks of the channel; however, large steep slopes remain unvegetated and may be a concern. Although no major slope failures were noted, bank erosion was evident in many places along both banks of the new extension channel in both Reaches 1 and 2. Erosive forces deposited a considerable amount of silt in parts of the channel in 2004 which has negatively affected substrate quality and biological function. It should be noted that some fine sediment is entering the spawning channel every year.

The lower portion of the new compensation channel (Reach 1) is primarily rearing habitat with low water velocity, an abundance of large, woody debris, and deeper areas of water. Habitat in Reach 2 was predominantly spawning type habitat with higher water velocity and substrate composed of more gravel/cobble. No features or obstructions to fish movement were noted in either reach of the channel. Results indicated that water quality in the spawning/rearing channel has been relatively constant over the six-year monitoring program, and should remain at the levels recently observed. Low pH values have often been reported, with values less than 6.5 measured consistently during the past two years.

With a combination of suitable rearing/spawning habitat and typically year-round favorable water quality/flow conditions, the channel appears to be able to support fish populations throughout the year. Large numbers of juvenile coho salmon were captured in the extension as well as below the access road culvert in the old channel during 2008-2009; few cutthroat trout, steelhead/rainbow trout parr and sculpins were also reported. Table 5 provides a summary of small salmonids and other fish species recorded for the McNab Creek spawning/rearing channel during the 6-year monitoring program.


Table 5 Salmonid and small fish usage by reach of the McNab Creek spawning channel from 2004 to 2009. (“Lower” is the old channel; “middle” is Reach 1; “upper” is Reach 2.)

Year Coho Steelhead/ Rainbow Trout

Cutthroat Trout Sculpin

2004 (2 visits)

10 – lower 10 - middle

NC NC NC

2005 6 – lower 16 – middle 28 – upper

NC NC NC

2006 10 – lower 15 – middle

1 upper

NC NC NC

2007 7 – lower NC – middle

1 – upper

NC NC NC


NC 3 - upper NC


3 – lower 2 – middle

2 - upper

7 – upper 1 sculpin – lower 2 sculpins – upper

In addition to use by salmon fry, adult spawning chum salmon have been observed in the channel during the November site visits. Table 6 shows the adult return numbers for the last six reporting years. No spawning fish were expected during the first year of monitoring since the channel had just been completed. Differences between previously recorded returns and those recorded for November 2007 may just be a matter of run timing versus the timing of the site visits. It may be that the 2007 timing was closer to the peak of the coho run rather than the chum run.

Table 6 Adult returns observed for the last six reporting years.

Sampling Date Adult Chum Adult Coho Carcasses

Year 1 – November 12, 2003 n/a n/a n/a

Year 2 – November 24, 2004 73 1 23

Year 3 – November 16, 2005 31 1 19

Year 4 – November 23, 2006 89 n/a 32

Year 5 – November 13, 2007 0 4 0

Year 6 – November 13, 2008 20 0 3

Invertebrates were observed on the substrate during 2008-2009. The observed invertebrates included small worms as well as aquatic larvae on submerged rocks (Figure 17). Caterpillars were found on shoreline rocks (Figure 18). The development of an invertebrate community is encouraging as they are essential to the channel’s ecosystem as a primary source of food for rearing juvenile salmonids.


Figure 17 Invertebrate larvae found on a rock in the new channel, November 2008.

Figure 18 Caterpillar from the middle reach found on shoreline rocks during the November 2008 visit.


5.0 CONCLUSIONS AND RECOMMENDATIONS

Howe Sound Pulp and Paper Limited Partnership has completed their obligations as per the Fisheries Act S. 35(2) Authorization No. 10-HPAC PA3-000-000935. Six years of monitoring the McNab Creek spawning/rearing channel following construction has shown that the channel is functioning as intended with salmon spawning in the stream, fry surviving from year to year, and aquatic habitat developing in terms of aquatic insects and algae. The slopes on the channel have stabilized following initial erosion in 2004; some fine sediments have accumulated on the substrate. Given the channel is primarily groundwater fed, erosion of stream banks is not considered an issue at this site. Riparian vegetation has improved over the six years and is helping to stabilize the stream banks and to provide cover.

This completes the 6-year monitoring program for the McNab Creek project. It is recommended that this Authorization be closed.


6.0 BIBLIOGRAPHY

Canadian Council of Ministers of the Environment (CCME). 2003. Canadian water quality guidelines for the protection of aquatic life. Canadian Council of Ministers of the Environment, 1999, updated 2003.

Government of BC. 2001. British Columbia approved water quality guidelines (criteria), 1998 edition, updated August 24, 2001. Water Protection Branch, Ministry of Water, Land and Air Protection. August 2001.

Hatfield Consultants Ltd. 2004. McNab Creek Spawning/Rearing Channel Monitoring Project: 2004 Annual Report. Prepared for Howe Sound Pulp and Paper Limited Partnership, Port Mellon, BC. August 2004.

Hatfield Consultants Ltd. 2005. McNab Creek Spawning/Rearing Channel Monitoring Project: 2005 Annual Report. Prepared for Howe Sound Pulp and Paper Limited Partnership, Port Mellon, BC. October 2005.




Johnston, N.T. and P.A. Slaney. 1996. Fish Habitat Assessment Procedures. Watershed Restoration Technical Circular No. 8. Watershed Restoration Program, BC Ministry of Environment, Lands and Parks, Victoria, BC.

Pollard W.R., G.F. Hartman, C. Groot, and P. Edgell. 1997. Field Identification of Coastal Juvenile Salmonids. Harbour Publishing. 32 pages.

RISC. 1999. Reconnaissance (1:20,000) Fish and Fish Habitat Inventory: Standards and Procedures. Version 2.0. Resource Inventory Committee, Victoria, BC.

RISC. 2000. Reconnaissance (1:20,000) Fish and Fish Habitat Inventory: Reach Information Guide. Version 1.0. Resource Inventory Committee, Victoria, BC.

Sim, S. 2004. Howe Sound Pulp and Paper Limited Partnership. Personal communication, August 2004.


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