TABLE OF CONTENTS

LIST OF TABLES

LIST OF FIGURES

1.0 INTRODUCTION

2.0 METHODS

3.0 GENERAL WATERSHED DESCRIPTION

4.0 INTERIOR WATERSHED ASSESSMENT PROCEDURE

5.0 CHANNEL ASSESSMENT PROCEDURE

6.0 FISHERIES HABITAT ASSESSMENT

7.0 WATER QUALITY SURVEY

8.0 LEVEL 1 ROAD CONDITION ASSESSMENT

9.0 RIPARIAN/WETLAND AREAS IMPACT ASSESSMENT AND BIODIVERSITY CONCERNS

10.0 SUMMARY

11.0 REFERENCES

Appendix A IWAP Spreadsheet Tables

Appendix B Bidwell Lake Habitat Report (1976)

Appendix C Lists of Fish Scale and Fish Samples

Appendix D Fisheries Assessment Photographs

Appendix E DFO/MELP Stream Survey Forms

Appendix F Road Assessment Reports

Appendix G Road Assessment Photographs

Attachment 3: Riparian impact aerial photographs

Table 3.1 Characteristics of Bidwell Creek

Table 4.1 Hazard Indices for the Bidwell Watershed

Table 5.1 Bidwell Creek Channel Sensitivity Ratings

Table 5.2 Bidwell Creek Detailed Assessment Data Sheet

Table 5.3 Channel Characteristics at Sites Inspected September 20-22, 1995

Table 5.4 Summary of Channel Impacts in the Bidwell Creek watershed

Table 6.1 Fish sampling site locations by reach and sampling effort

Table 6.2. Fish capture data for the streams that were sampled

Table 6.3 Fish habitat quality summary by reach.

Table 7.1 Bidwell Creek water quality: September 22-23, 1995.

Table 8.1 Bidwell creek summary road assessment

Figure 3.1 Overview map of the Bidwell Creek watershed

Figure 3.2 Longitudinal Profile of Bidwell Creek

Chendi Enterprises Inc. has completed a set of integrated watershed assessments for the Bidwell Creek watershed. The assessments were funded by the Watershed Restoration Program of Forest Renewal B.C. This report presents the results of a level 1 Interior Watershed Assessment (IWAP) study, a stream channel assessment (CAP), a fisheries habitat assessment, water quality sampling, a road condition assessment, and an evaluation of riparian and wetland impacts and biodiversity concerns. The field components of these assessments were completed in September and October 1995.

The overall objectives of the assessment program conducted in the Bidwell Creek watershed were to:

Specific objectives of each assessment are outlined in the appropriate section.

Methods employed for the assessments included in this report were based on the current guidebooks developed as part of the Watershed Restoration Program and the B.C. Forest Practices Code (Ministry of Forests/Ministry of Environment, Lands and Parks, 1995a; MELP/MoF, 1994; MoF/MELP, 1995b; MoF/MELP, 1995c; Moore, 1994). Specific methods used for each assessment are provided in the appropriate section (Sections 4.0 to 9.0).

The Bidwell Creek watershed is located about 125 km west of Williams Lake, B.C., within the Fraser Plateau physiographic region (Figure 3.1). Bidwell Creek is a tributary of the Chilko River, which is in turn a tributary of the Chilcotin River. The watershed area is 264 square kilometres. The elevation at the mouth of Bidwell Creek is 937 m and the elevation at the highest point of the watershed is 1917 m, a difference of 980 m. Figure 3.2 shows the longitudinal profile of the mainstem of the creek. The stream gradient averages 1.4%, ranging from less than 1% through much of the middle reaches, to about 25% just upstream of the mouth. Additional morphological characteristics of the basin are provided in Table 3.1.

Figure 3.1 Overview map of the Bidwell Creek watershed

Figure 3.2 Longitudinal Profile of Bidwell Creek

Table 3.1 Characteristics of Bidwell Creek

The closest climate station to the Bidwell Creek watershed with recent data covering all months is at Tatlayoko Lake (51° 40’N latitude, 124° 24’W longitude, elevation 853 m). The mean (1928-1990) total annual precipitation is 428.8 mm with 130.6 mm of the total falling as snow (Atmospheric Environment Service, 1993). The mean January and July daily temperatures are -6.8° C and 13.9° C respectively. At Alexis Creek, where the climatic conditions are probably closer to those in the Bidwell watershed, climate data was collected by the Atmospheric Environment Service for the period 1961-1983, and data are unavailable for a number of months. Estimates of temperature have been made by extrapolation, and the mean January and July temperatures are estimated as -15° C and 11° C. Estimates for mean precipitation have been made by graphically comparing monthly data for Williams Lake with the available Alexis Creek data. From this, the mean total precipitation at Alexis Creek is estimated to be 461 mm, with 288 mm as rain and 173 mm as snow.

The lower part of the watershed is mapped as being in the Interior Douglas fir (IDF) biogeoclimatic zone. This accounts for about 20% of the total watershed area. The remainder of the watershed is mapped as within the Sub-boreal pine-spruce (SBPS) biogeoclimatic zone, although some areas in the upper watershed could be included in the Montane Spruce (MS) and Engelmann Spruce-Subalpine Fir (ESSF) zone, based on field reconnaissance.

Bidwell Creek lies within the Fraser Plateau physiographic region of B.C. The landscape is largely a remnant of volcanic flows during the Tertiary period (5´ 10⁶ to 66´ 10⁶ years before present), modified by subsequent erosion (Ryder, 1978). The Tertiary surface has been capped by more recent lava flows in places. Large areas of the Fraser Plateau are undissected and are made up of flat to gently rolling terrain. Outcrops of volcanic rocks are present in the lower Bidwell watershed.

Surficial deposits in the Bidwell watershed include morainal till, fluvial-glacial, fluvial and organic materials (Resource Analysis Branch, 1972). The lower two-thirds of watershed was a meltwater channel during deglaciation (Tipper, 1971a; 1971b), as indicated by terraces and ridges adjacent to the present stream channel, and a generally wide floodplain. A number of smaller meltwater channels are also present, most draining toward the main drainage. Near the mouth, the creek flows through a remnant channel of the Chilko River, which flowed north of its present location at one time. There are several eskers in this area.

Soils in the watershed include Gray Luvisols, Gleysols, Eutric Brunisols, Regosols, and Organic soils (Resource Analysis Branch, 1972).

The B.C. Ministry of Environment, Lands and Parks (MELP) has maintained a flow gauge near the mouth of Bidwell Creek since 1987 (Station #08MA007). The gauge consists of a modified H-flume with a stage recorder in a stilling well. At the time that this report was prepared, data were only available for 1987-1990, since the later data has not been compiled.

Even within the 1987-90 period, limited data are available. There are no data at all for the November to March period, and only 1988 and 1989 have data covering six consecutive months. Based on the available data, average monthly flows ranged between 0.006 and 0.023 m³/s. Peak flows occurred in April or May. The maximum instantaneous discharge among the available data was 0.166 m³/s of April 17, 1989, although this value is not considered valid due to potential instrumentation problems. Recommendations regarding analysis of post-1990 data and ongoing monitoring are made in section 5.0.

The objectives of the Interior Watershed Assessment Procedure (IWAP) conducted for the Bidwell Creek watershed were to:

A Level 1 Watershed Assessment is a reconnaissance level investigation designed to identify impacts that have arisen from the cumulative effects of past forest harvesting or planned future forest harvesting. The Level 1 IWAP for the Bidwell Creek watershed generally follows the methods outlined in the Interior Watershed Assessment Procedure Guidebook (Ministry of Forests/Ministry of Environment, Lands and Parks, 1995a). Steps include dividing the watersheds into sub-basins, assessing the hydrologic sensitivity of each sub-basin based on a number of watershed descriptors, and asking a series of questions relating to four potential hazard groups: peak flow, surface erosion, riparian buffer, and landslides.

Scores are assigned to each descriptor and a Hazard Index Score is assigned to each hazard group. According to the guidebook, a hazard index score above 0.5 is intended to indicate the need for further work in that sub-basin, that is, a Level 2 Channel Assessment. If all hazard indices are less than 0.5, the suggested interpretation is that there are limited cumulative impacts and no further analyses are required to assess impacts of past forestry activity. Note that for this study, a level 2 Channel Assessment was conducted for each sub-basin without regard to the outcome of the level 1 IWAP study.

Information for the Bidwell Creek Level 1 IWAP was derived from:

• 1:50,000 - topographic base maps (93 C/1, 92 O/13, 92 N/16, 93 B/4)
• 1:20,000 Forest Cover maps (1994) (92N.089, 92N.090, 92N.099, 92N.100, 92O.091, 93C.010,)
• 1:50,000 Forest Cover maps (composites based on the 1:20,000 Forest Cover maps)
• 1:250,000 Surficial Geology maps (1291A, 1292A)
• 1:50,000 Soils map (92 O/13E)
• 1967 Aerial photographs (black-and-white; scale approximately 1:31,400)
• 1993 Aerial photographs (colour; scale approximately 1:15,000)

Watershed Area: Watershed boundaries and sub-basin boundaries were outlined on 1:50,000 scale NTS maps. The total watershed area is 264 km² and includes three sub-basins: Lower Bidwell (48 km²), North Bidwell (85 km²), and Upper Bidwell (131 km²). The watershed boundaries are shown on Figure 3.1.

H₆₀ elevation: The elevation contour in a watershed for which 60% of the watershed area is at a higher elevation is known as the H₆₀ line. It is calculated from a hypsometric curve, which is the line plotting cumulative watershed area against watershed elevation. According to the IWAP guidebook, the relevance of this contour is that in the B.C. Interior, snow typically covers the upper 60% of a watershed when streamflow levels begin to peak in the spring (MoF/MELP, 1995a). With respect to its influence on peak flows, therefore, forest harvesting at higher elevations is of more importance than harvesting at elevations below H₆₀.

Hydrologic Recovery: Hydrologic recovery refers to the process by which the hydrologic regime of a watershed returns to pre-harvest conditions as trees grow. A level 2 channel assessment was to be conducted for the watershed regardless of the outcome of this level 1 study. Therefore, tree heights within logged polygons were estimated using air photos and height classes provided on forest cover maps, rather than the more time consuming method using detailed forest inventory data. All map polygons with height classes greater than one (i.e., height >10 m) were assumed to be fully (100%) recovered. For polygons with height class one (0-10 m), the majority of the logging took place in the early to mid 1980s, and field observations indicated that natural regeneration has been moderately successful. For these conditions, a recovery of approximately 25% would be generated by the method of MOF/MELP (1995a). Therefore 25% recovery was assigned to all polygons with a height class of one. Polygons labeled NSR, blocks planted since 1992, and urban and cultivated lands were all assigned a recovery of 0%.

Equivalent Clearcut Area: The Equivalent Clearcut Area (ECA) is the area cut, reduced by an amount representing hydrologic recovery. ECA calculations are used to determine the peak flow hazard index. The ECA takes into account clearcut areas (open cut blocks), selectively logged areas (minimum 40%), areas that have not been sufficiently restocked (NSR), and urban and cultivated lands. Open Range Land was excluded from ECA calculations.

Roads: All roads within the Bidwell Creek watershed shown on the 1994 Forest Cover base maps were considered for the purposes of the road inventory portion of the IWAP. This includes main forest roads, branches, spurs, landings, and wagon roads. After completing this inventory, it was learned that the Forest Cover base maps, although dated 1994, indicate about 5% less total road length than is evident on the 1993 aerial photos. The 1993 aerial photos were thus used to update the Forest Cover maps for the purpose of the level 1 road condition assessment reported in section 8.0. In addition, due to recent and ongoing logging in the Lower Bidwell Creek sub-basin, neither the Forest Cover Maps nor the 1993 aerial photos provide an up-to-date road inventory. For this reason, the calculated hazard index related to roads for Lower Bidwell Creek sub-basin is lower than if the recent forest harvest activities had been accounted for.

Erodible Soils: Limited published surficial geology or soils information exists for the Bidwell Creek watershed. Thus estimates of soil erodibility were based on visual inspections of road cuts and stream banks conducted during the stream channel and road condition assessments completed in the watershed during September and October 1995. Much of the basin is composed of coarse glacial till, with some outwash and riverine deposits. Most of the riparian zone areas, where the fine to medium grained textured soils exist, are level, which reduces the overall risk of erosion.

Streams: All watercourses indicated on the 1:20,000 scale Forest Cover maps are considered in the Level 1 IWAP. This includes ephemeral, intermittent, and permanently established streams. In the IWAP, "length of stream logged" refers to sections of stream that have been logged right up to and across the channel. Fish-bearing streams were identified based on results of the fisheries habitat survey (Section 6.0).

Landslides: A landslide was identified only if it is visible on air photographs (scale 1:15,000). Unstable channel banks or road cuts were not considered landslides.

Roads on Unstable Terrain: Since terrain maps are unavailable for the Bidwell Creek watershed, those roads constructed on slopes greater than 60% (MoF/MELP, 1995a) were considered as "roads on unstable terrain".

Roads within 100 m of Stream: Most roads in the Bidwell Creek watershed cross streams at angles near 90⁰, rather than running parallel to streams for significant distances. Therefore the estimate of road length within 100 m of streams was obtained by multiplying the number of stream crossings by 200 m (i.e., 100 m on each side of the stream crossing).

Table 4.1 summarizes the results of the watershed assessment in terms of the four hazard groups. Highlighted in bold are hazard areas of concern in each sub-basin (i.e., where the hazard index > 0.5). At 0.49, the peak flow hazard index for the Lower Bidwell sub-basin was sufficiently close to 0.5 to merit inclusion. The parameters used to formulate a hazard index for each of the four hazard groups are summarized on the spreadsheet tables which were used to calculate the indices. These are contained in Appendix A.

Table 4.1 Hazard Indices for the Bidwell Watershed

Results of the IWAP point to the following as areas of concern:

Lower Bidwell Sub-basin Peak Flow

North Bidwell Sub-basin Riparian Buffer

Upper Bidwell Sub-basin Peak Flow and Riparian Buffer

As described earlier, the IWAP was completed using the most up-to-date maps available. However road construction and harvesting has taken place in the Lower Bidwell sub-basin since the maps were produced. If the new areas could be accounted for, the Peak Flow Index would be greater than 0.5. However it is unlikely that the remaining indices for the Lower Bidwell Sub-basin would increase beyond the 0.5 threshold, based on the known distribution of erodible soils and the location of the road network.

Based on the results of the Level 1 IWAP, a Level 2 Channel Assessment would be recommended for all three sub-basins in the Bidwell Creek watershed. As indicated above, a channel assessment was completed for each of the three sub-basins. The results of the Level 2 assessment are presented in the following section of this report.

The general objective of the Channel Assessment Procedure (CAP) analysis is to identify changes in stream channel characteristics that are "clearly and unequivocally" the result of past logging practices (MoF/MELP, 1995b). Channel characteristics covered include channel bed character, stream bank impacts, stream morphology (i.e., pool-riffle sequences), and effects associated with large woody debris (LWD) in the channel. Other direct impacts addressed in the CAP include landslides reaching the channel and logging in the riparian zone.

Specific objectives of this assessment were to:

1. Review aerial photographs of the Bidwell Creek system to identify changes in channel characteristics between successive photo sets (1967 vs. 1993);
1. Complete field assessments to determine if past forestry activities have caused channel impacts, focusing on potential impacts identified by the Level 1 IWAP analysis (Section 4.0), a review of aerial photographs, and potential impact sites identified from a helicopter survey;
1. Identify any sites on the stream channel which have been impacted by forestry activities; and
1. Develop prescriptions for site restoration, as needed.

Methods used in this assessment are based on the Channel Assessment Procedure (CAP): Level 2 Analysis, Version 1.0 (MoF/MELP, 1995b). That document is a draft and was not in a complete form at the time of the assessment. The methods employed in this assessment were thus modified based on experience with similar assessments. The field assessment was conducted from September 19 to 22, 1995 by Dr. Hugh Hamilton, P.Ag. The field work was done in conjunction with the fish habitat and riparian assessment survey (Sections 6.0 and 9.0).

The aerial photograph review examined valley and stream morphology prior to the initiation of logging (using 1967 black-and white aerial photos) and as of 1993 (using colour aerial photographs). The scale of the 1967 photographs is about 1:31,400. At this scale, a 10 m wide stream is about 0.3 mm wide. On the 1:15,000 scale photos, the same stream is about 0.7 mm wide. Throughout the Bidwell Creek watershed, the stream channels are less than 5 m wide, and are typically less than 2 m wide, making it difficult to identify the "obvious and significant" changes in stream morphology that the CAP "General Assessment" aerial photograph analysis requires. Thus a "Detailed Assessment" was completed.

The "Detailed Assessment" examined a total of seven stream macro-reaches, five on the Bidwell Creek mainstem (Lower and Upper Bidwell sub-basins) and two on the North Bidwell tributary (Figure 5.1). Table 5.1 shows the resulting channel sensitivity ratings, based on Tables 3 and 4 in the CAP manual (MoF/MELP, 1995b). Following is a brief description of the channel characteristics for each Sensitivity Class.

No landslides were noted on either the 1967 or 1993 sets of aerial photos. The assessment procedure does not require that landslides be present, but looks at the potential for landslides to be "connected" to the stream channel if they occur. Through most of its length, Bidwell

Table 5.1 Bidwell Creek Channel Sensitivity Ratings

Creek has a relatively wide valley-flat bordered by slopes that are less than 20% gradient. For these areas, the hillslopes and channels are "unconnected", and the sensitivity rating is low. Exceptions are reaches #1 and #5 of the mainstem, where some sections of v-shaped valley exist with a narrow valley-flat, and are thus "partially connected." If a landslide occurred, some debris could be carried to the channel. These reaches were assigned a moderate sensitivity rating.

For this sensitivity category, the assessment looked for evidence of alluvium (e.g., gravel bars and islands) within the channel. If alluvium was present continuously along both banks, there is high potential for new inputs of sediment to be stored, creating the opportunity for channel instability. These areas were assigned a high sensitivity rating. Reaches with fragmentary or discontinuous alluvial deposits in the channel were assigned a moderate sensitivity rating, and reaches where alluvial deposits are absent from the channel were assigned a low rating.

In Bidwell Creek, alluvial deposits were only visible on the aerial photographs in Reach #1, in a short section near the Chilko Lake road. Reach #1 was assigned a moderate rating based on this section, even though conditions along the majority of the reach merit a low rating.

No evidence of channel movement between 1967 and 1993 were noted anywhere in the watershed, and no new deposits of alluvium were present on the 1993 photos compared to 1967.

Upstream disturbance refers to evidence of direct forestry impacts in upstream reaches (e.g., sediment wedges at the toe of landslide scars, riparian zone logging). In Bidwell Creek, the only cases where forest harvest is close to the main channel of the creek are in the upper watershed. No landslides are visible on the air photos, and riparian buffers are present. However, the buffers appear somewhat thin in some locations, and cover along the channel obscures evidence of impacts. Thus moderate sensitivity ratings were applied to Reach #5 of the mainstem and Reaches N-1 and N-2 of the North Bidwell tributary.

Table 5.2 summarizes the results of the "Detailed Assessment". Despite only two of the seven reaches having a moderate overall sensitivity rating, this made up 10.5% of the total channel network length examined. This is greater than the threshold of 5% channel length impacted that required a field assessment under the CAP. Based on the assessment procedure, Reaches #1 and #5 require field assessment.

Field work for the Bidwell Creek stream channel assessment was initiated with a helicopter overview flight on September 19, 1995. The flight provided a quick evaluation of general watershed morphology and the amount of forest harvest activity in the watershed. It also permitted a number of sites to be identified for detailed ground assessments.

As described earlier, the channel assessment field work was conducted in conjunction with the fish habitat survey. At each site inspected, channel morphology and discharge data were collected. The channel was examined for evidence of sediment accumulation, bank instability, scouring, and excessive amount of LWD. The sites inspected on the ground were in reaches #1, #2 and #5.

Table 5.2 Bidwell Creek Detailed Assessment Data Sheet

Following is a series of descriptions of the sites along the Bidwell Creek stream network which were covered by the field assessment. Site numbering took place during the helicopter survey, with additional sites added during the ground inspection (Figure 5.1). The site descriptions are presented in the order in which the inspections took place. Stream channel characteristics for each site are summarized in Table 5.3.

Site #11 Crossing of the Eagle Main Road over Bidwell Creek

The flow passes through a corrugated steel pipe (CSP) culvert beneath the road. A second smaller culvert is in place to handle high flows. The outlet of the main culvert sits about 0.2 m above the channel bed, and could pose a barrier to upstream fish passage (see Section 6.4). The second culvert discharges about 1 m above the stream bed at the side. The road crossing is perpendicular to the channel across a low gradient floodplain. The road ditches which drain to the creek were in good shape with little indication that they recently carried any flow. Sediment (sand, fines) has accumulated in the small sedimentation pond at the culvert inlet, although there is no blockage. There was no indication of bank erosion either above or below the road crossing. All woody debris appeared natural in origin, and there was no evidence of sediment accumulation behind debris.

Measurements of channel morphology were obtained in the stream section about 100 m upstream of the crossing (Table 5.3). The valley-flat area adjacent to the channel is characterized by organic soils over glacial till, with alder and fir providing good cover and shade. Stream banks are generally moss covered with little exposure of mineral soils.

Prescription: The culvert outlet is a potential barrier to upstream migration by fish. The culvert should be re-installed to lie flush with the stream channel bed. Once this is complete,

Table 5.3 Channel Characteristics at Sites Inspected September 20-22, 1995

routine maintenance of the road and ditches by the licensee should be adequate to minimize future fisheries impacts at this location.

Site # 9a Small tributary just south of Site #11

This site is the crossing of the Main Road over a small tributary. A single culvert carries the flow. The culvert outlet is suspended about 1.5 m above the channel, and is thus a barrier to fish passage. However fish are unlikely to be present (see Section 6.4), and thus remediation is not needed. Water was pooled in the catch basin at the culvert inlet, and small amounts of mineral (sand and silt) and organic fines had accumulated in the pool. The ditches along the road have been seeded with grasses and clover, and there is little evidence of flow. The stream has good cover and is well shaded both upstream and downstream of the road. Natural woody debris is present throughout and has created step pools.

Site #9 Road Crossing

This site is a road crossing of what was originally thought to be a tributary of Bidwell Creek. However flow measurements indicate that this is the mainstem, since the discharge was estimated to be 0.127 m³/s, as compared to 0.006 m³/s in the creek at Site #11 (Table 5.3). A single CSP culvert carries the flow. The culvert is accessible to fish. Pools are present both at the inlet and at the outlet, where flow has had a scouring effect. As was the case for the other crossings along this road, the ditches have been seeded with grasses and clover, and there is little evidence of erosion along the ditch.

With the exception of the immediate culvert outlet area, there was no evidence of channel or bank scour, or of sediment accumulation in the channel. The stream in this area has good cover of alder and spruce. Lodgepole pine are present within 10 m of the channel. Natural woody debris is present in places, providing channel habitat heterogeneity.

A secondary road runs parallel to the main road about 100 m upstream of this site. The culvert has been removed and the channel of Bidwell Creek restored to its natural width.

Prescription: Riprap should be installed along about 5 m of the channel banks below the culvert outlet to prevent further bank erosion near the outlet.

Site #8 Road Crossing of Small Tributary through a Cutblock

This is a small tributary of Bidwell Creek which flows through a cutblock. No buffer was left in place in the sections of the stream just above and below the road crossing. The channel has an average width of about 0.5 m. There are fine sediments accumulating in the catch basin at the culvert inlet, but the flow was not impeded. The culvert outlet is partially blocked by cobbles and boulders. Just below the cutblock, the channel is composed of a series of step pools formed by natural woody debris. It is unlikely that this tributary is fish-bearing (see Section 6.4). Trees on the cutblock are becoming re-established, and no additional stream restoration is needed at this site.

Site #12 Road Crossing near Headwaters

At this site the Eagle Lake Road crosses Bidwell Creek over a single CSP culvert, approximately 500 m from the upper watershed boundary. The site is about 200 m upstream of Site #10 (see below), and the channel characteristics are similar. The crossing is situated in a forested riparian zone between two large cutblocks. The road upstream of the culvert intercepts flow from a number of springs on the upper cutblock. The flow proceeds down a ditch on the left side of the road (looking upslope) and joins Bidwell Creek just downstream of the crossing. Surface materials on the cutblocks are glacial till with many boulder size erratics visible. The riparian zone is relatively narrow (20 m), with organic soils over glacial till.

The spring flow is held in a small pond (approx. 10 m diameter) before discharging to the ditch. The pond likely retains sediment, although some fine sediment from the cutblock could be discharged during large rain events and during peak snowmelt. Some surface erosion was noted on the road, with sediment being directed to the ditch.

Prescription: Improvements to the small settling pond at the seep could prove beneficial in reducing sediment inputs to Bidwell Creek. Also, the feasibility of installing a cross-drain with a riprap apron should be examined, as a means to divert sediment onto the slope rather than into the creek.

Site #10 Channel Adjacent to Large Cutblock

This site is located at the base of a very large cutblock. The riparian buffer is less than 50 m, and is as small as 25 m in places. However, no channels or gullies were observed which "connect" the hillslope to the channel and serve as routes for sediment input. Road and landings have been re-vegetated on the cutblock, and tree cover is being re-established naturally.

The riparian zone resembles a treed bog, with Sphagnum moss, Labrador tea and other typical bog species. The stream banks consist of organic soils which have been undercut. The channel consists of a series of boulder step-pools with an overall gradient of 10% (the 6% gradient shown in Table 5.3 is for the specific control section used in the flow measurement). The substrate between the boulder steps is primarily fines (mineral and organic) over some sand, gravel and cobbles.

Despite the narrowness of the riparian buffer, there was no logging within the riparian zone, and there is little blowdown. The channel is stable with no signs of sediment accumulation. No specific channel restoration procedures are required. Reforestation and road deactivation in the cutblock should be adequate to reduce the risk of future direct impacts.

Site #13 Small Channel through Large Cutblock

This channel is a tributary of Bidwell Creek. Logging took place across the channel, and no buffer was retained. It is possible that the flow was ephemeral prior to harvest, at least on the upper part of the block. Since harvest, riparian shrubs (willow, alder) have flourished, along with sedges and other wetland plants. As a result, the channel area appears quite green when viewed from the air compared to adjacent cutblock areas.

After flowing through a short forested section downstream from the cutblock, the tributary flows under the Eagle Lake Road through two culverts. The drop at the downstream end of the culverts is about 0.5 m, and likely constitutes a barrier to fish passage. However, in addition to the culvert, there are a number of natural features that are potential barriers to fish passage (boulder steps, natural woody debris).

Site #15 Bidwell Creek Mainstem - Downstream of Unnamed Lake ("Lulua Lake")

The Lulua family operates a small ranching operation adjacent to the lake which is part of the Bidwell Lakes chain. For the purposes of this assessment, the lake is referred to as Lulua Lake. Just below the lake outlet, the Bidwell Creek channel is a low gradient stream bordered by swamp and wet meadow. Channel characteristics at this site are summarized in Table 5.3. Beavers are active, although the Lulua family works to control them by breaking the dams and occasional trapping. The meadow areas have been cleared and fenced for hay production. According to Doris Lulua, water levels in their hay fields and adjacent areas are higher since logging took place in the upper watershed (see section 9.0). Ms. Lulua also stated that the taste of the water in Bidwell Creek has deteriorated to the point that the family has ceased to use the creek for domestic water, and they now bring water in by truck. Potential effects of forest harvest on stream flow and water quality are discussed in Section 5.4.

Site #4 Bridge over Bidwell Mainstem

The bridge was constructed in July 1995 and crosses Bidwell Creek at a right angle. Just upstream of the bridge the creek flows around an island. The riparian zone is relatively wide. At approximately 100 m, it is about 25 times wider than the average stream channel width. The floodplain contains organic soils (peat) formed over riverine sands and gravels. The adjacent banks at the edge of the floodplain are glacial till which include particles ranging from clay to boulders.

Although the bridge is in very good condition, there is an exposed cutslope on the north side of the creek where the road enters the floodplain. The exposed soil continues to streamside such that any eroded sediment could be carried to the stream channel. As well, cattle use the exposed area to access the creek.

Prescription: The bank and exposed soil are potential sediment sources and should be remediated. Since the road is relatively new, the responsibility for restoration likely falls with the licensee rather than being a WRP project. The bank should be graded back to an appropriate grade and all exposed areas seeded with a Canada No. 1 grass-legume mixture, or another appropriate seed mix to be determined.

Site #1 Reach #1 - from Chilko River Road to the Mouth

The final 200 m of Bidwell Creek above the Chilko River confluence is a series of block-steps formed by boulders up to 2.5 m diameter. The boulders are primarily basaltic colluvium. The channel width averages 1.8 m. The flow is typically directed through a narrow channel between boulders as it drops over each step. These drops range up to 1.6 m in height, and a portion were blocked with natural woody debris. The substrate in the pools ranges from coarse sand to gravel. The average gradient of the final 50 m is 23%. Given the gradient and height of the steps, this reach is probably a barrier to fish attempting to move up Bidwell Creek from the Chilko River.

The reach from the road to the mouth is contained in a v-shaped valley. There is no evidence of past logging in the valley. The banks of Bidwell Creek appeared stable and there was no evidence of sediment accumulation or channel aggradation or degradation.

A flume with stage recorder is located on Bidwell Creek between the Chilko River Road and the mouth (see Section 3.4). The station is maintained by the Water Management Branch of B.C. MELP. Stage on the day of the site visit was 25 cm.

At the Chilko River Road crossing, the flow passes through two CSP culverts. The flow at the crossing appeared to be less than the flow at the mouth, indicating that there is a subsurface component to the flow as the stream passes through the coarse fluvial-glacial materials in the old channel of the Chilko River. There are no signs of sediment accumulation near the crossing, and the banks appeared stable.

Site #: 2 (51°56.00’N, 123°52.00’W)

The cutblock here is well back from the channel above the left (north) bank. There are no tributaries flowing through or near to the block and hence little potential for debris or sediment to be transported to the main channel.

Site #: 3 (51°56.1’ N, 123°53.8’ W)

A tributary to Bidwell Creek is shown on the 1:50,000 scale map to be draining the cutblock at this site. During the helicopter flight it was noted that no stream channel is present in the gully that connects the block to the valley flat. A buffer was retained along the entire length of the cutblock, and no impacts on water quality or fish habitat were noted.

The results of the Interior Watershed Assessment Procedure completed for the Bidwell Creek watershed (Section 4.0) required that the Level 2 Channel Assessment Procedure be completed on all three sub-basins. The first phase of the Channel Assessment Procedure, the aerial photograph assessment, breaks down the stream network into reaches for the next level of evaluation. The results of the CAP indicated that Reaches #1 (nearest mouth, Lower Bidwell sub-basin) and #5 (upper portion of Upper Bidwell sub-basin) required field assessments, but that the North Bidwell sub-basin did not. Nevertheless, some level of field investigation took place in all three sub-basins.

The field assessments found few direct channels impacts due to forest harvest activities. No landslides were noted anywhere in the Bidwell Creek watershed. No evidence of channel movement was noted either on the aerial photographs or in the field. As well, there were no cases of excessive amounts of logging related large woody debris in the channel, and no sites with significant channel aggradation (a build-up of alluvial sediment due to increased sediment yield). A number of minor channel impacts were noted, that nevertheless could have at least local effects on water quality. These are summarized in Table 5.4 along with the recommended mitigation prescriptions.

As described earlier, there is anecdotal evidence of increased water levels and changes in water quality in recent years, since the large-scale forest harvest took place in the Upper Bidwell sub-basin. Although there is no direct evidence for these phenomena in the watershed, such changes are consistent with patterns found elsewhere. Numerous studies from around the world have shown that removal of vegetation by clear-cut logging results in increased water yield (e.g., Bosch and Hewlett, 1982; Harr, 1983; cited by Hicks, et al., 1991). The increase in stream flow is caused by reductions in losses of water related to forest vegetation through interception, evaporation, and transpiration. The global average increase in annual flow is estimated as 34 mm/yr for a 10% decrease in forest cover (Calder, 1993). As forests re-grow, annual water yields generally return to pre-harvest levels, although the rate of re-establishment varies depending on the tree species present, climate, soil and altitude.

In addition to changing annual water yields, forest harvest also influences the timing of flows. Depending on the size of forest openings (i.e., clear-cuts) and watershed aspect, snow melt can occur earlier, resulting in earlier and larger spring peak flows (Reksten, 1991). During dry periods, decreases in interception and transpiration resulting from forest harvest result in flows being maintained that otherwise might decrease to negligible amounts (Calder, 1993).

With respect to water quality, forest removal can increase the leaching of nutrients and cations from soils (Calder, 1993). Due to decreased interception and transpiration, more water is free to pass through the soil layers, thus increasing the potential for leaching. From the point of view of potability, this is most likely to increase hardness and total dissolved solids compared to pre-logging conditions. This may be the effect referred to by the Lulua family.

Table 5.4 Summary of Channel Impacts in the Bidwell Creek watershed

In the Bidwell watershed, the relatively high rates of forest harvest which occurred since 1985 are partly attributable to efforts to control mountain pine beetle. The ECA for the whole watershed, and for the Upper and North sub-basins as of early 1995 were between 16% and 19%, and the Lower sub-basin had an ECA of 29% (subject to the assumptions used to estimate hydrologic recovery in section 4.3.1). These values are close to the 20% rule-of-thumb threshold at which changes in a watersheds regime may begin to become detectable (Reksten, 1991). If increases in water yield do occur, they are typically in the range of 30-40 mm for every 10% reduction in forest cover (Calder, 1993; Reksten, 1991). These data are derived from a wide range of studies covering watersheds with more humid climates than Bidwell Creek. Nevertheless, it is possible that significant increases in water yield may have occurred in the Bidwell watershed compared to pre-logging conditions, and this change in yield may have been accompanied by changes in water quality. Once the post-1990 hydrological data from MELP become available, it is recommended that an evaluation of possible water yield increases be undertaken. Future monitoring of discharge and water quality is recommended to assess changes that may result as the net ECA changes, either through reforestation (decreased ECA) or additional harvest (increased ECA). Water quality changes are discussed in more detail in Section 7.3. If hydrological changes are determined through additional study to be significant, the only feasible mitigation is to reduce the watershed ECA, since the changes are watershed-scale phenomena.

Stream inventory and habitat assessments were conducted for the Bidwell Creek watershed to evaluate habitat types and to determine the distribution of fish in all streams in the Bidwell Creek watershed. Sampling for fish presence/absence and species identification was carried out in order to assess the current status of fisheries resources within the watershed. The assessment and fish sampling work was completed by Mr. Mark Gollner, R.P.Bio. during the week of September 19-23, 1995. Mr. Leslie Hunlin assisted with the sampling in addition to providing information on watershed resources and resource use.

Existing stream inventory information for the Bidwell Creek system was reviewed prior to initiating field surveys. Available information consists only of a lake survey data sheet for Bidwell Lake (Fish and Wildlife Branch, 1976), dated October 14, 1976. This information provided a starting point as to what species of fish to expect during the field sampling study and is included with this report as Appendix B.

The field survey was initiated with a helicopter flight of the study area. The purpose of the flight was to assess the major features and barriers of the streams in and around the Bidwell Creek mainstem. This enabled identification of any obstacles possibly limiting fish distribution within the study area. The flight also provided the basis for identifying stream reaches, as fish species and abundance may differ from reach to reach. Immediately following the helicopter flight, maps (1:50,000 NTS and 1:20,000 forest cover) and colour aerial photographs of the Bidwell Creek drainage were reviewed to assess potential fish barriers and habitat features.

Sampling sites were chosen in order to quantify fish distribution in all reaches of Bidwell Creek and its tributaries, taking into consideration any existing fisheries inventory data. These sites were then assessed using a combination of three sampling techniques. The most frequently used sampling method was backpack electrofishing. The procedures followed the standardized electrofishing methods regulated by the Fisheries Branch, B.C. Ministry of Environment, Lands and Parks (MELP). Fishing effort using this technique is presented in terms of catch per unit effort (CPUE), equals number of fish captured divided by total number of seconds electrofished). The second most frequent sampling technique in the Bidwell Creek survey was Gee (minnow) traps. This method was only used in areas where electrofishing was not possible (i.e. deep pools, lakes and ponds, and in swift and shallow water), and in areas where no fish were caught with the electrofisher, to verify the absence of fish. Fishing effort using the Gee trap method is presented as CPUE (number of fish captured per day). The third method, angling, was only used in Lulua Lake to determine presence or absence of larger fish.

For the electrofishing sampling, all streams were surveyed while moving in an upstream direction to minimize visual obstruction by sediment stirred into the water column and to facilitate the capture of fish. The frequency and voltage settings found to be effective in the streams surveyed were 70 Hz and 300 - 600 volts respectively. The voltage settings were quite variable, with effectiveness being highly dependent on water quality. All fish captured were netted and immediately transferred to a bucket containing ambient stream water. Species and length in millimetres (fork-length) were recorded for each fish caught. The fish were returned to the water when they were completely revived. A few representative fish were preserved in isopropyl alcohol from selected streams for the purpose of species verification. As well, scale samples were taken from representative salmonids captured. A list of fish samples and scale samples is included in Appendix C. All scale and fish samples were submitted to MELP in Williams Lake for analysis and inclusion in the MELP database. No fish mortalities were observed resulting from the electrofishing conducted during this study.

A photographic log was kept during the field study. Photographs for each of the streams surveyed are presented in Appendix D. The photos have been scanned and the digital images are presented on tape in Attachment 2. Stream width measurements were measured in the field and recorded for use in determining the riparian class for each reach of the stream sampled.

At sites where Gee traps were deployed, the trap was baited with salted salmon roe and submerged. The submerged trap was secured in place by tying it to an overhanging bank or to a stationary piece of wood, flagged and the time recorded. After a minimum period of 12 hours the trap was retrieved, and the time recorded. All fish captured were measured (fork-length), species identified, and released back to the stream.

Five reaches were delineated on the main stem of Bidwell Creek (Figure 5.1). Reach #1 extends from the mouth up to a point upstream of the Chilko Lake Road, a distance of 1.15 km. The average gradient is 4.8%, although some sections just above the mouth are 20-25% where the stream flow cascades through large boulders. Reach #2 is 3.375 km long and has an average gradient of 1.8%. The reach is incised and the valley walls are comprised of exposed bedrock and talus slopes. Reach #3 is a low gradient (0.8% average) reach that is much less incised than Reach #2. It is 4.38 km long. The upper reach break is the first lake of the Bidwell Lakes chain. Reach #4 is a long (27.05 km) low gradient (0.8% average) reach that is characterized by numerous lakes and wetlands. Reach #5 is the uppermost reach of the Bidwell Creek mainstem. The average gradient is 5.0% and it is 4.25 km long.

Fish sampling results for all of the sites sampled between September 19 - 23 are summarized in Table 6.1. This table also includes catch per unit effort (CPUE) data. The CPUE values

Table 6.1 Fish sampling site locations by reach and sampling effort

resulting from the electrofishing sampling are presented as number of fish captured per second (fish/second), and the CPUE for minnow trap sampling and angling are represented as number of fish captured per day (fish/day). Rainbow trout (Oncorhynchus mykiss) and White sucker (Catostomus commersoni) were the only species of fish found in the portions of the streams surveyed. Electrofishing was done only in those streams with sufficient flow to permit sampling and which had access by foot or vehicle.

All fish sampling locations have been mapped on Attachment 1 (1:50,000 scale map). Photocopies of all field notes as well as DFO/MELP Stream Survey Forms are included in Appendix E.

The fish catch data for the sites surveyed are summarized in Table 6.2, including the range in fork-lengths. Many of the tributary streams in the study area were steeper gradient ephemeral streams or streams with inadequate flow to support fish presence. These streams were not sampled, but professional judgement was used to assign a riparian class to them.

The 420 mm (fl) Rainbow trout captured in Lulua Lake died as a result of swallowing the lure. A scale sample was taken and the gut contents were examined. The gut contained almost exclusively molluscs (freshwater clams) as well as a smaller amount of insects and other invertebrates. The scale sample was submitted to the MELP office in Williams Lake for analysis. Results are not yet available.

An analysis of the results from all of the combined sampling techniques indicates that some of the streams surveyed contained resident fish populations ranging in age from "young-of-the-year" (0+) with 40-50 mm fork-lengths, to fish older than three years with up to 420 mm fork-lengths (length-age relationships from Scott and Crossman, 1973).

Table 6.2. Fish capture data for the streams that were sampled

Stream Name (site & reach number)	Capture Method*	Fish Species	Number Captured	Range of Fork-lengths (mm)
Bidwell Creek (site 11, reach 5)	EF	Rainbow trout	1	95
Bidwell Creek - tributary (site 9, trib.)	EF	No Fish	0	N/A
Bidwell Creek (site 10, reach 5)	EF	No Fish	0	N/A
Bidwell Creek - Lulua Lake (reach 4)	MT (1)	No Fish	0	N/A
	MT (2)	No Fish	0	N/A
	MT (3) ANG	No Fish	0	N/A
	ANG	Rainbow trout	2	390, 420
Bidwell Creek (site 15, reach 4)	EF	Rainbow trout	6	53 - 168
	EF	White sucker	12	125 - 165
Bidwell Creek (site 4, reach 4)	EF	White sucker	42	40 - 150
Bidwell Creek (site 1, reach 1)	EF	Rainbow trout	1	100
Bidwell Creek - Bidwell Lake (reach 4)	MT (1)	White sucker	0	N/A
	MT (2)	White sucker	16	10 - 120
	MT (3)	White sucker	26	10 - 120
* EF = electrofishing
* MT = minnow-trap
* ANG = angling

All of the streams surveyed in the Bidwell Creek watershed are streams or tributaries to streams with significant fisheries values.

Following are brief descriptions of stream habitat at the sites visited during the field surveys. The site numbers correspond to those given in section 5.0 - Channel Assessment. Potential impacts on fish habitat are outlined. In most cases, any prescriptions required to address fish habitat concerns are the same as those needed to address channel impacts, and have been presented in Section 5.3.2. Several of the sites described below were only viewed from the helicopter survey and were not inspected on the ground. These are indicated as such.

Site #: 1 Chilko River Road Crossing (Reach 1) 59° 55.4’ N, 123° 49.1’ W

The culverts coinciding with the road at this site are not posing a fish barrier and do not appear to be affecting the water quality downstream. There is excellent fish habitat for both spawning and rearing at this site and there are no logging related impacts here. The 1-2 m high eroding banks upstream from the culvert are a source of spawning size gravels to the channel.

Site #: 4 Bridge Crossing (Reach 4) 59° 56.2’ N, 123° 57.3’ W

There has been extensive use of the stream and riparian habitat by beavers at this site. Two large beaver dams were seen downstream from the bridge, both of which have been broken open. Immediately upstream from the bridge there is recent evidence of beavers having cut trees and introducing woody debris to the channel.

There is an abundance of excellent fish rearing habitat and some areas with spawning gravels at this site. Much of the channel substrate is covered by aquatic mosses, grasses, periphytic algae and milfoil, providing excellent rearing and foraging areas for resident fish. Some of the pools at this site are 1.5 - 2 m deep and would serve as overwintering habitat for fish. No Rainbow trout were captured at his site, however they were captured at sites both upstream and downstream from this site. White suckers were caught here, supporting the observation that this area has very good rearing habitat values.

Site #: 5 (Helicopter survey only; north branch) 59° 57.0’ N, 124° 06.7’ W

Little to no flow was observed at this site at the time of the helicopter flight. This would indicate a lack of suitable fish habitat. Fish (White suckers) are abundant downstream in Bidwell Lake, however access to this site may not be possible due to low flow. The gradient is low (< 2%) and this site is close to the headwater of this branch of Bidwell Creek. It is not apparent whether there are beaver dams or other natural barriers downstream from this site, between Bidwell Lake, preventing upstream migration of fish in Bidwell Lake.

Site #: 6 (Helicopter survey only; Reach 4) 59° 55.2’ N, 124° 00.1’ W

The road at this site, as viewed during the helicopter flight, is several hundred metres from the right bank of the channel. No streams or gullies were observed that might transport fines from the road towards the main channel Bidwell Creek. This road may join the road that crosses the bridge at site #4. There was no impact on the channel observed at this site.

Site #: 7 (Helicopter survey only; Reach 4) 59° 52.1’ N, 124° 12.5’ W

This site is very similar to site #2 in that the cutblock here is well back from the channel. It is above the channel along the gently sloping valley on the right bank. No water courses were noted from the helicopter or on the 1:50,000 map.

Site #: 8 Small Tributary through a Cutblock (trib. to Reach 4) 59° 52.0’ N, 124° 14.0’ W

The tributary at this site does not have sufficient flow or suitable habitat to support fish. Reach 1 of this tributary, 200 - 300 m downstream from the cutblock boundary, may have sufficient flow at certain times of the year, although this was not confirmed.

A buffer was retained along the stream banks on the upstream side of the road, but not downstream from the road. This could affect stream water temperatures. However, there is already some regeneration of deciduous growth along both banks of the channel downstream from the road, and water temperature effects are expected to be minimal.

Site #: 9 Road Crossing (trib. to Reach 4) 59° 51.8’ N, 124° 14.6’ W

The culvert at this site has restricted the natural channel width from approximately 2 m down to 1 m and has caused scouring of the channel substrate downstream (see Section 5.3.2). The culvert is not a barrier to upstream fish migration. There is excellent fish habitat at this site, however no fish were captured using the electrofishing technique. It is possible that there is a barrier at some point between site and the confluence with the next downstream tributary of Bidwell Creek. There is also the possibility that fish moved downstream to avoid the low water temperature, which was 6°C at the time of the survey.

A secondary road crossing of this tributary is located approximately 100 m upstream from the main road. The culvert has been removed and the channel restored. The portion of the stream surveyed between the main road to a point 200 m upstream of the restored crossing has excellent spawning and rearing habitat.

Site #: 9a Road Crossing (trib. to Reach 4) 59° 52.0’ N, 124° 14.8’ W

Water flow at this site was not sufficient for electrofishing, and it is not likely that fish would be found here due to low flows. However, if fish do have access to the portion of the tributary downstream from the road, the culvert would pose as a migration barrier.

Recommendation: Stream sampling for fish presence or absence should be done during higher flow conditions to determine whether fish are present at this site.

Site #: 10 Reach at Toe of Large Cutblock (Reach 5) 59° 52.9’ N, 124° 17.9’ W

A buffer was retained along almost the entire length of the channel. The small portion that was logged across the channel has some LWD and other debris across and in the channel. The stream channel at this site is < 1 m wide, with low flow and flows through a series of small cascades and chutes created by the cobble-boulder substrate (see Section 5.3.2). No fish were captured at this site and it is not likely that fish would have access to this site even during periods of higher flow.

Site #: 11 Road Crossing (Reach 5) 59° 52.7’ N, 124° 14.7’ W

This site is very similar to site #9 in that the culvert here restricts the natural stream channel width from 3 m down to 1 m. The culvert outlet is approximately 20 cm higher than the surface of the stream and is posing as a potential barrier to upstream fish migration. This is supported by the fact that fish were captured downstream from the culvert and not upstream. There is also a smaller overflow culvert beside the main culvert. There is an accumulation of sediment in the catch basin at the upstream end of the culverts.

The fish habitat in the proximity of this site is excellent for both spawning and rearing. There are undercut banks, overhanging vegetation, and areas of spawning size gravels both upstream and downstream from the culvert. There is an increase in stream gradient approximately one km upstream that is probably a natural barrier to upstream fish migration.

Prescription: The main culvert should be realigned to lie flush with the channel bed in order to enhance upstream fish passage (see Section 5.5).

Site #: 12 Road Crossing near Upper Divide (Reach 5) 59° 52.9’ N, 124° 17.9’ W

The culvert here is at the upstream extent of the cutblock at site #10 and is close to the headwaters of the stream. There is no apparent erosion around the culvert and it is not a fish barrier. There is some good fish rearing habitat at this site. However, it is unlikely that fish can migrate past the culvert at site #11 or past the series of chutes and cascades at site #10. Steps to control sediment inputs at this site have been outlined in Section 5.3.2.

Site #: 13 (trib. to Reach 5) 51°52.9’ N, 124°15.2’ W

This site is a small tributary flowing through the cutblock on the upslope side of the road. The tributary joins Bidwell Creek just upstream from site #11. No buffer was retained along the channel as it flows through the cutblock. Some regeneration of deciduous vegetation has occurred but there are still many areas of the channel that are unshaded. The lack of a buffer could effect stream water temperature. The fish habitat is moderate to poor at this site, due to a narrow channel width (< 0.5 m), low flow, and numerous cascades averaging 30 cm in height.

Site #: 14 Road Crossing (Reach 4) 59° 52.7’ N, 124° 14.7’ W

The two culverts here are both barriers to upstream fish migration. This site is only a few hundred metres from site #11 and has suitable fish habitat downstream from the culverts. Despite the fact that the culverts are fish barriers, there is no suitable habitat upstream from the road. Less than 10 m upstream from the culverts there is a 50 cm high chute through cobbles and natural LWD. Beyond this the gradient and low flow combine to create poor fish habitat upstream from the road.

No restorative measures are required at this site in relation to fish habitat or water quality.

Site #: 15 (Reach 4) 51°53.20’ N, 124°09.9’ W

Excellent fish spawning and rearing habitat is present downstream from the bridge near the outlet of a Lulua Lake (see Section 5.3.2). An abundance of both species of fish present in the Bidwell Creek watershed, Rainbow trout and White sucker, were captured at this site. The aquatic plants, periphyton, undercut banks, and overhanging vegetation provide an abundance of cover and forage areas for the resident fish. There is evidence of recent beaver activity at this site but it appears as though the local residents have trapped and/or are discouraging them from building dams.

No direct logging impacts were observed at this site however, two local residents said that the water level has risen and that there are more frequent fluctuations in water level since logging occurred in the upper watershed (see Section 5.5).

Site: Lulua Lake (Reach 4) 51° 53.1’ N, 124° 09.9’ W

This lake has healthy populations of Rainbow trout (RB) and White suckers (WSU). Angling sampling produced two RB (390 & 420 mm fl) in only 15 minutes, numerous others were seen rising for food on the surface of the lake, and hundreds of RB were observed swimming in the shallows along the shore. Three Gee (minnow) traps were set in the southern end of the lake but no fish were captured. This is surprising in that many schools of juvenile fish (RB and WSU) were seen swimming among the reeds and grasses along the shore.

There has been no direct logging impact along the shore of the lake, however there has been extensive logging in the headwaters of Bidwell Creek and some of its tributaries. This logging may have an affect on the frequency and magnitude of peak flows.

Site: Bidwell Lake (Reach 4) 51°56.80’ N, 124°01.8’ W

Bidwell Lake is the only site at which there is historic inventory data. The study done in 1976 showed that Rainbow trout and Longnose suckers were present in the lake. The current study only resulted in the capture of suckers. No angling or net sampling was done so it is possible that trout are still resident in the lake. The suckers were captured using Gee traps and have been identified as being White suckers. This identification requires verification and therefore a sample has been submitted to MELP. No logging impacts were noted in the vicinity of Bidwell Lake. They lake and its inlet and outlet streams have excellent habitat for both spawning and rearing resident fish.

The Bidwell Creek watershed was found to have few direct impacts to fish habitat due to forest harvest activities. The impacts that were found are related either to culverts or cutblocks where no buffer was retained along the stream. These problem areas can be relatively easily and effectively restored to their pre-impact condition with relatively little effort and moderate funding. All of the impacted sites have good road access.

A major factor impacting fish habitat and water quality within the Bidwell Creek watershed is beaver activity. There has been extensive tree and shrub harvesting of the riparian zone in reaches 2, 3, and 4 (on the mainstem) and reaches 1 and 2 (on the north fork) by beavers for construction of dams and lodges and for food. The removal of this riparian vegetation has reduced stream cover and exposed much of the channel to direct sunlight. The extensive beavers dams are preventing resident fish from accessing areas of the stream channel with spawning size gravels and other areas with potential rearing habitat.

Using the fish habitat diagnostics table in Technical Circular No. 8 (MELP/MOF, 1994; see Table 2) as a guide, conclusions about fish habitat quality can be drawn based on the field assessment work. These conclusions are summarized for each reach in Table 6.3.

In general, there is very good habitat for both spawning and rearing resident fish in the Bidwell Creek watershed. The presence of 1-2 kg Rainbow trout in Lulua Lake is an indication that food is abundant and that the lake has good fish habitat values. In addition to restoring the sites identified by the channel assessment procedure (Section 5.5), the health of the system could possibly be improved by controlling beaver activity within the watershed. However additional investigations on the influence of beavers on fish habitat in the watershed are required before this can be stated conclusively.

The late sampling date (September 19 - 23) may have resulted in not finding fish at sites where they are present at other times of the year. Many of the sites where fish were expected and not found, based on their presence upstream and/or downstream at other sites, should be sampled again when water levels and temperatures are higher. Any future fish sampling should be accompanied by measurements of flow and water temperature, and water quality sampling.

Table 6.3 Fish habitat quality summary by reach.

Water quality sampling took place on September 22 and 23, 1995. Samples were collected from six locations on Bidwell Creek, plus one from Lulua Lake (Figure 5.2). The samples were obtained in clean 1 L Nalgene containers that were rinsed three times with ambient water, and kept in coolers with ice packs. Samples collected on September 22 were refrigerated overnight. When the sampling was complete, the samples were transported in coolers to the DFO laboratory in West Vancouver for analysis.

The analyses were conducted by Ms. Tracey Jeffrey of DFO using standard methods (APHA, 1992). Nutrient analyses were completed using an autoanalyzer.

The results of the analyses are summarized in Table 7.1. Where criteria exist, the data are compared against B.C. and Canadian criteria for drinking water and protection of aquatic life (B.C. MELP, 1995; CCREM, 1993).

Concentrations of total phosphorus ranged from 5.3 to 23.8 m g/L, and concentrations of total dissolved phosphorus ranged from 4.7 to 22.9 m g/L (Table 7.1). Phosphorus is the nutrient most responsible for algal blooms in fresh water. The threshold concentration for algal growth is about 5 m g total P/L (Sawyer, et al., 1994), although nuisance levels of algae in water do not usually occur until about 50 m g total P/L (McCutcheon et al., 1993).

Table 7.1 Bidwell Creek water quality: September 22-23, 1995.

Concentrations of nitrate-N ranged from 0.3 to 10.0 m g/L. All samples were much lower than the criteria for drinking water of 10,000 m g/L, and the protection of aquatic life criteria of 40,000 m g/L. Ammonium-N values ranged from 1.8 to 8.8 m g/L. Again, these concentrations were well within the aquatic life criteria, which is 1130 m g/L. In general, the levels of nitrate-N and ammonium-N found in Bidwell Creek were very low. McCutcheon et al. (1993) report a typical nitrate-N value of 230 m g/L for streams and rivers, and a typical ammonium-N value of 10-10,000 m g/L.

The waters of Bidwell Creek have a neutral to slightly alkaline pH. Alkalinity values ranged from 55.2 to 315.2 mg CaCO₃/L, and averaged 179.4 mg CaCO₃/L, which is somewhat higher than the average alkalinity value of 123 mg CaCO₃/L determined from surveys of a large number of natural rivers (McCutcheon et al., 1993). This indicates that Bidwell Creek has a relatively high buffering capacity. High alkalinity values have no public health consequence (Sawyer et al., 1994), although very high values can render water highly unpalatable.

Conductivity, or more correctly specific conductivity, averaged 169.4 m S/cm. Conductivity is a measure of water’s ability to conduct an electrical current, and is related to the total dissolved ionic solids. Streams and rivers typically have values of 70 m S/cm, but can range up to 1500 m S/cm (McCutcheon, 1993).

Total suspended solids concentrations were very low. At Sites #1 and #9, concentrations were below the detection limit of 1 mg/L. The average for all sites was 1.1 mg/L, which is below the typical range of 10-110 mg/L reported by McCutcheon et al. (1993). However, it is important to note that the samples were obtained as grab samples. Proper sampling for suspended sediment requires that the sampler not disturb the flow. Also, grab samples do not represent the full vertical stream profile. For these reasons, the results as obtained should be seen as only rough indicators of the suspended solids concentrations in Bidwell Creek.

Total dissolved solids averaged 144.5 mg/L. This is above the typical range for streams and rivers of 73-89 mg/L, although values range widely between streams (McCutcheon et al. (1993), and values up to 300 mg/L are not uncommon. TDS data provide a broad indication of water quality, since it is a measure of the ionic strength of water, which influences the mobility and transformation of metals and other compounds

Dissolved oxygen (DO) concentrations in the system averaged 10.4 mg/L, which was 95% saturation. One sample, Site 4, had a concentration of 8.9 mg/L, which is below the CCREM criteria for early life stage cold water biota of 9.5 mg/L. However, the sample was analyzed about 48 hours after the sample was obtained, which may have been sufficient time to reduce the DO concentration. All samples had DO concentrations above the minimum required for the protection of other life stages, which is 6.5 mg/L.

Water quality data collected over two days in September 1995 represents a "snapshot" in time. Results indicate that the waters of Bidwell Creek are low in total nutrients but have alkalinity, conductivity, and total dissolved solids that are somewhat on the high side of typical values obtained from a large number of natural streams and rivers. Dissolved oxygen levels were adequate for the protection of early life stage cold water biota at all but one site, although the below-criteria value may be attributed to the long holding time before analysis. Overall, water quality in Bidwell Creek presents few constraints to aquatic life production in the system, based on the available data.

Watershed residents have noted a decrease in water potability and have begun obtaining their domestic water from other sources. As outlined in Section 5.5, the watershed equivalent clearcut area (ECA) is sufficiently high to make it feasible for water quality to have been affected through increased leaching of cations. This could result in changes in alkalinity, conductivity, total dissolved solids, hardness and possibly other parameters. In the absence of pre-logging water quality data, there is no way to state conclusively that this has happened in Bidwell Creek. Additional monitoring covering a range of seasons and flow conditions is recommended.

A Level 1 assessment of the roads within the Bidwell Creek watershed was conducted, according to the guidelines outlined in Watershed Restoration Technical Circular No. 3 (Moore, 1994). In addition to satisfying the Level 1 road assessment requirements, the present study also examined the role of roads in two areas: (1) in providing hunter access to remote areas of the watershed, and (2) in negatively impacting stream riparian areas and wetlands. The role of roads with respect to these two issues is addressed in section 9.0. The present section focusses specifically on road maintenance and deactivation issues resulting from drainage, erosion, and stability concerns.

All roads within the watershed can be classified either as forest roads (mainlines, branches, and spurs) or as wagon roads - rough narrow tracks developed as transportation routes which predate logging activity. Forest roads either fall within current licence obligations, or remain behind from lapsed tenures. Consistent with the objectives of the Watershed Restoration Program, the scope of the present study was to conduct an overview evaluation of all forest roads within the watershed which are not included within current licence obligations. Thus the wagon roads were excluded, as were roads under current tenure arrangements (for which maintenance and deactivation requirements remain the responsibility of the licence holders).

Landings were also examined during field inspections. In general, the deactivation status and the condition of landings was found to be consistent with that of the associated road. Therefore, landings are not explicitly identified in this assessment. All landings on roads targetted for Level 2 prescription work should be examined during the Level 2 inspections.

The Bidwell Creek watershed (Figure 3.1) is accessed from Highway 20 by three main forest roads: Eagle Main, Pyper Lake Road, and "5600" (referred to here as South Main); and by wagon roads. These include the Chilko Forest Road, which travels along the Chilko River and crosses Bidwell Creek near its confluence with the Chilko River. As indicated in section 3.0, the watershed is in general characterized by relatively level and rolling topography, except in the westernmost headwaters area, which includes some steeper hills. Most roads run along relatively gentle terrain, and there are few road sections located parallel to and in close proximity to streams. In general, therefore, road-related drainage and sediment problems within the watershed are relatively rare, and are usually minor in significance. However, many roads have been inadequately deactivated, and some follow-up prescription and deactivation work is certainly required.

The three above-noted forest roads and their branches provide easy two- and four-wheel drive access to many areas of the watershed. Although the Eagle Main and Pyper Lake Road are open and are being maintained, the areas accessed by these roads are no longer experiencing active logging operations; and these areas therefore formed the focus of the study.

The area accessed from South Main ("5600") is under current licence obligations, and active logging was underway during the road inspections conducted during
October 1995. All roads in this area have been constructed since 1993, as the only road on the 1993 air photos in this area is the wagon road along the route of the modern "5600". This area was briefly inspected from the air, but no follow-up recommendations are made, since the maintenance and deactivation of these roads are now governed by the Forest Practices Code of B.C. Act.

The present contract includes the requirement to complete a Level 2 road assessment, i.e. to provide road deactivation prescriptions for roads targetted by the present study as requiring remedial work. A budget for the Level 2 work is to be determined following submission of this Level 1 assessment report.

The specific objectives of the Level 1 road assessment study were as follows:

6. Summarize the assessment results in a written report (section 8.0).

This section presents the results of the assessment work. As indicated above, the role of roads with respect to wildlife, and riparian and wetland areas are addressed in section 9.0.

Forest cover mapping at a scale of 1:20,000 was assembled for the Bidwell Creek watershed. Six such maps are required to fully cover the watershed: 92 091, 92 N089, 090, 099, and 100, and 93 C010. Two 1:50,000 scale composite maps created from these base maps were obtained from Chendi Enterprises Ltd., and used as the basis for field inspections.

The road assessment involved both a field and an office component. In the field, overview inspections were conducted by 4 wheel drive (4WD) truck, on foot, and by helicopter on October 17 and 18, 1995. The inspections were completed by Dr. Brian Guy and Mr. Percy Guichon. The assessment team was accompanied by Mr. Joe Kuhn, whose role was to evaluate access, and wildlife and riparian habitat impacts associated with the road network. Weather during the inspections was generally sunny, with air temperatures above freezing, and no snowcover was present. Roads were generally dry, and the roads which would under normal conditions be accessible to truck travel were easily driveable by 4WD truck.

All roads within the study area (including some not indicated on the 1:50,000 map used for field work) were viewed from the air, during a reconnaissance helicopter overflight. In addition, most roads were inspected by vehicle, by driving very slowly and stopping where necessary to inspect sites where notable maintenance or deactivation issues were apparent. Notes were made on a continuous basis, and at notable sites, and photographs (Appendix G) were taken to illustrate key issues and typical conditions. Following the review of each road, summary observations on that road were recorded, and a qualitative judgement on the risk to environmental resources was applied. Roads which were inaccessable to vehicle travel were partially inspected on foot. Through these various means, all roads within the scope of the study were inspected in the field.

Several tasks were subsequently completed in the office, as follows. First, all roads where notes were incomplete from the reconnaissance overflight were examined using aerial photographs (1993, colour, scale 1:15,000). Second, the road network shown on the 1:20,000 forest cover maps was updated, using the 1993 air photos supplemented by field observations. The additional roads and road lengths added to these maps have not been plotted using accurate stereoplotting techniques. Rather the locations are only approximately correct, on the basis of manual data transfer from the air photos. Third, all notes, photographs, methods, and results were summarized.

All roads present on the 1993 aerial photos are shown and labelled on Attachment 1. The map is up-to-date (i.e. to October 1995) for most of the watershed. However, in the portion of the watershed downstream of Bidwell Lakes (within the Lower Bidwell sub-basin), there has been significant road-building activity since the 1993 photos were flown. Note that the South Main is indicated on the map as a main road, although it existed only as a wagon road in 1993; and that two of several present-day branch roads are also indicated. (These roads have been plotted for reference purposes, because they are referred to later in this report.) The new roads in this area fall outside the scope of the present study, since they fall within current licence obligations.

Results of the overview road assessment for all roads within the scope of the study are summarized in Table 8.1. Detailed road assessment reports are presented in Appendix F, and photographs are presented in Appendix G. In addition, the photos have been scanned and the digital images are presented on tape in Attachment 2. Table 8.1 presents several types of information on each road, including its location (referenced by mapsheet and UTM coordinates), the mainline by which it is accessed, its type and length, the method by which it was examined, the state of access to the road, its driveability and deactivation level, and the environmental risk and work priority.

The table is organized into logical sections, in which all roads derived from each of the mainlines are grouped together. Roads are grouped under the following mainline headings: Eagle Main, Cochin Main, Lulua Main, Pyper Lake Road, North Main, and South Main. Note that Lulua Main, North Main, and South Main are "project" names, chosen arbitrarily for the purposes of the present study. It is possible that these roads are also known by other names. The labels applied to branch and spur roads were also chosen arbitrarily, for the purpose of the present study.

Eagle Main and Cochin Main, which are still being used to access areas beyond the watershed boundaries, are maintained as active forestry roads. Many of the other roads in the watershed have been deactivated, although the level of deactivation varies from none, to seasonal, to semi-permanent, to permanent. In addition, the effort applied to deactivation varies, and since there is no evidence of ongoing maintenance on seasonally deactivated roads, there are various degrees of deactivation success. As a result, many roads are deactivated to an inappropriate level, many have not been properly deactivated, and some require rehabilitation followed by deactivation to the appropriate level. However, since hillslopes and road grades within the watershed are in general not steep, and since roads do not in general run parallel to streams, the environmental risks and the work priorities associated with these issues are in most cases considered to be low. The only exceptions are found on roads accessed by Eagle Main and Lulua Main.

Decisions on desired deactivation levels fall within the mandate of the Chilcotin Forest District. Therefore, to the extent possible, we have not discussed the appropriate level of deactivation, but rather have focussed on what was observed in the field, i.e. deactivation inadequacies and road-related problems. Prior to conducting a Level 2 road assessment (involving road restoration prescriptions) it will be necessary to acquire the input of the Chilcotin Forest District, local people, and other resource users with respect to the desired deactivation status for each road.

The following paragraphs summarize observations and recommendations for roads accessed by each of the mainlines:

Some deactivation effort has been applied to most of the roads accessed by Eagle Main. However, the level of deactivation and the effort applied to deactivation varies greatly. Minor problems were noted on many of these roads. Some serious problems were also observed, in particular on E1, E3, and E6. Level 2 work should focus on these roads. All other roads in this area were assigned a "low" risk rating and either a "low" or a "none" work priority rating. Some concerns were noted on Eagle Main. However, Eagle Main is an active main road, and its condition is therefore governed by the Forest Practices Code of B.C. Act. Thus, recommendations for level 2 assessment work are not required in the present report. Some problems not evident during the helicopter overflight were observed on the air photos on E1.3, E1.4, E1.5, E3.2, and E10. The condition of these roads should be re-checked in the field during the level 2 prescription work.

Cochin Main is an active mainline, and was inspected by vehicle. Access to an extensive spur road network in a large block north of Cochin Main via roads C1 and C2 has been blocked. All roads derived from C1 and C2 were therefore inspected from the air, and all appear to be semi-permanently deactivated and in good condition. Access to branch and spur roads on the south side of Cochin Main via C3, C4, C5, C6, and C7 is uncertain, as these roads were not shown on the 1:50,000 scale field map and access was not noted in the field. However, as viewed from the air, these roads appear to be semi-permanently deactivated and do not appear to be presenting a significant risk to the environment.

Lulua Main itself has not been deactivated, although there is no active logging occurring in any of the areas accessed by this road. However, the road grade is very gentle, and it is not considered necessary to implement deactivation measures.

Some of the roads accessed from Lulua Main have been well deactivated and are in good condition. However, drainage problems were observed on some roads, notably L2 and L2.3. Minor problems were seen on L2.2, and L1.5 appears to be experiencing some cutslope erosion, as observed on the 1993 air photos. Level 2 follow-up work should include each of these roads.

Although some of the roads accessed from the Pyper Lake Road do not appear to have been properly deactivated, inspections failed to find significant problems associated with any of these roads. From the perspective of erosion and drainage control, none of these roads represents a priority for follow-up level 2 prescription work.

North Main itself was inspected by vehicle from the Pyper Lake Road junction to an impassable cross-ditch 2.9 km south of this point. Within this length, two notable problems relating to fill stability and one relating to drainage were noted. Level 2 work should address these issues. Beyond the above-noted cross-ditch, all roads (including North Main) have been temporarily deactivated, and have had waterbars and cross-ditches installed. No significant problems were observed during an aerial inspection. However, consistent with the intent of the Forest Practices Code of B.C. Act, because of the remoteness of this location, semi-permanent deactivation may be more appropriate for these roads than temporary deactivation.

The South Main accesses active logging areas within the Lower Bidwell sub-basin. Examination of this road and the associated branch and spur roads was beyond the scope of the present study. However, since these roads were viewed during the aerial recconaissance, notes have been summarized for South Main and two branches on Table 1. The Chilko Forest Road has also been listed on Table 1, although it too was beyond the scope of the present study. It is understood to be in poor condition, and it should therefore be considered while planning a rehabilitation and deactivation program for the Bidwell Creek watershed. It is possible that the status of this road is currently being addressed as part of the management plan for the new T’silhos Provincial Park at Chilko Lake.

Several conclusions have been drawn on the basis of the results presented in section 8.0:

On the basis of the above-noted conclusions, several recommendations can be made:

Table 8.1 Bidwell creek summary road assessment

pages 63-67 reserved for table 8.1 (5 pages long)

Consistent with the general knowledge reported on page 1 of the Riparian Management Area Guidebook (MoF/MELP, 1995c), Bidwell Creek riparian and wetland areas, usually connected, contain many of the highest value non-timber resources in the watershed, and appear to contain a high number of plant and animal species. In general, impacts to these sensitive landscape features were not found to be extensive or severe. Nine locations were identified requiring detailed assessment addressing three impact considerations: 1) direct habitat loss or modification, 2) continuity disruptions effecting animal movement corridors and other Forest Ecosystem Network (FEN) considerations, and 3) enhanced access where increased hunting pressure and related animal behavioral responses are likely to result in biodiversity and resource management impacts. The latter consideration is judged to be much more significant at present than the others. However, it must be noted that the potential for impacts on the Bidwell FEN will increase significantly if the practice of clearcut harvest continues in the watershed.

The Bidwell landscape unit at present contains no designated protected areas or critical habitat areas. FEN, wetland and other wildlife habitat features have also not been mapped at operational planning scales (1:20,000 or 1:50,000) and it is recommended that this work be conducted prior to further forest harvesting. As discussed at the initiation of this project, the highest priority for future work regarding policy, planning, and management decision-making in the Bidwell landscape unit is the completion of an access management plan. Tsilhqot'in government leaders and staff who initiated this project expressed grave concerns regarding the past, present and potential future impact of road access to high value habitats for large mammals. The numbers of moose, deer, and bears are all believed to be declining and road access to riparian and wetland areas, especially those more exposed by clearcut logging, is viewed to be the primary cause.

The nine impact areas identified in this project are located on the project map in Attachment 1. Aerial photo numbers are indicated on the map and digital copies are provided in Attachment 2. Hard copies are provided in Attachment 3. Seven of the impact areas are found in the predominant SBP5xc biogeoclimatic subzone with two (areas 101 and 151) on the ecotone with MSxv.

As both the natural environmental conditions and development impacts are very similar at all nine of the identified areas, the impact and mitigation considerations can be discussed generally for all of them at this level of assessment. Site assessment and prescription work at the next level will be more quantitative. Decision making with regard to access and habitat needs will require further consultation.

Direct impacts from forest harvesting, range use, silviculture and recreation activities in terms of vegetation removal or modification are not significant for ground cover and shrub layer vegetation components and soil erosion is not a problem, except for some very limited bare surfaces at bridge crossings and culvert sites reported earlier. Overstory removal is a problem for two reasons: loss of cover and loss of wildlife trees. Further discussion of these issues is presented in section 9.3. Consultation with the Wildlife Branch indicated that there are no identified mule deer winter ranges or other critical habitats in the Bidwell Landscape Unit. Informal discussions were conducted with Tsilhqot'in Elders and others with substantial experience and knowledge of fish, wildlife and indigenous plant resources in the Bidwell area. The following is a summary of a more formal interview conducted by Irvine Charleyboy and Percy Guichon with Casimir Lulua and his sister Doris Lulua. The interview was conducted on January 30, 1996 at the Lulua’s cabin which is located in the upper watershed of Bidwell Creek. The Lulua’s are members of the Nemiah Valley Indian Band, and have been ranching here for forty-six years. Currently, they have thirty-six head of cattle and seven horses.

All of the nine impact areas identified in this assessment contain very small streams with narrow riparian areas and/or small wetlands (i.e., less than 100 ha). Although limited in area, they contain relatively high value wildlife foraging sites and probably are major determinants of movement corridors. "Walk through" assessments focusing on ungulate pellet groups and browse utilization confirmed higher levels for the riparian/wetland than for adjacent dry forest types. The three biogeoclimatic subzone classes found in the Bidwell landscape unit (SBP5xc, IDFdk₄, MSxv) all emphasize "dry" or "very dry" as a characteristic, thus pointing out the high value potential of the limited wetland areas. Finally, the nine impact concern areas all have road access and open vistas from or near the roads, much of this provided by clearcuts.

Although the Riparian Management Area Guidebook (MoF/MELP, 1995c) not available when this assessment was conducted, the Biodiversity Guidebook (MoF/MELP, 1995d) provided many useful concepts for developing site-specific management strategies and prescriptions to accommodate resource management objectives. The most important of these for this project is the Forest Ecosystem Network (FEN) concept which, when related through an integrated planning process to access management and other elements of a comprehensive landscape plan, will provide general environmental protection and resource management objectives for the watershed. Government planners from local, provincial and federal land and resources programs, must be directed and adequately resourced by their leaders to achieve this much needed planning. With the resulting input from interest groups and local individuals with experience and knowledge regarding good stewardship practices that would be appropriate to Bidwell Creek ecosystem realities, planners can define system needs and site specific resource management objectives. Prescriptive restoration measures can then be developed where needed.

In addition to and in support of the much needed FEN and access management plans, the following concepts from the Biodiversity Guidebook can be applied to restoration planning for the nine riparian/wetland impact areas identified in the Bidwell watershed:

Roads intersecting riparian and wetland habitats, especially in or adjacent to a clearcut which has removed overstory cover and wildlife trees, are producing adverse impacts at nine locations in the Bidwell watershed. The impacts are of two types. First, loss of cover, nesting/denning, roosting and feeding sites for many wildlife species. Second and most significant is increased hunting access and enhanced vision and clear shooting range. This results initially in increased harvest and ultimately in avoidance response and reduced population levels.

Ground cover restoration work for erosion control and forage production is not warranted. Because of the FEN and wildlife tree considerations listed above from the Biodiversity Guidebook (MoF/MELP, 1995d), it is recommended that wetland/riparian corridors at the nine impact areas be considered for revegetation prescription work, focusing on creation of wildlife tree patches of local poplar trees and other desirable wildlife habitat enhancing species, especially forage shrubs. This prescription work could be tied in with road restoration project development. Further justification for this work is to be found in Table 17 of the Riparian Management Area Guidebook (MoF/MELP, 1995c), which states that "provisions should be made for residual cover and other attributes to meet requirements of dependent wildlife species". Restoration planting will not be required at all nine of the impact locations but consultation and further field assessment by Bidwell Project workers and area resource managers are needed to determine needs and preferred techniques.

The other mitigation consideration, access management, is beyond the scope of this assessment but, as noted above, access and FEN planning for the Bidwell landscape unit can provide valuable input to site restoration planning. Moreover, this assessment has established that local wildlife resource users have serious concerns regarding road access to the high value wetland/riparian habitat areas and current and potential adverse effects of over-hunting on biodiversity and harvest levels.

The Bidwell Creek watershed has a total area of 264 km² and includes three sub-basins: Lower Bidwell (48 km²), North Bidwell (85 km²), and Upper Bidwell (131 km²). Through most of its length, Bidwell Creek is a low gradient stream characterized by a wide valley flat and adjacent lakes and wetlands. There is a steep section just above the mouth where the slope is about 23%, as well as some reaches with moderate gradient near the headwaters. As of spring 1995, the equivalent clearcut area (ECA) in the watershed was 19% (subject to assumptions regarding hydrologic recovery outlined in section 4.3.1). Forest harvest is most concentrated in Upper Bidwell, although cutblocks are present throughout the watershed.

The Interior Watershed Assessment Procedure (IWAP) completed for Bidwell Creek generated four Hazard Indices; peak flow, surface erosion, riparian buffers, and landslides. Indices were greater than 0.5 for the following:

Lower Bidwell Peak flow

North Bidwell Riparian Buffer

Upper Bidwell Peak flow and Riparian Buffer

These results indicated that a Level 2 channel assessment was required.

The aerial photograph review of the watershed, which is the first phase of the Level 2 assessment, determined that two of the seven stream reaches analyzed had channel sensitivity ratings indicating moderate impact potential. The remainder had low impact potential ratings. No reaches had a rating of high impact potential. The reaches with the moderate rating, and thus requiring a field assessment, were Reaches #1 and #5 of the mainstem of Bidwell Creek.

The field assessments found few direct channel impacts due to forest harvest activities. No landslides were noted anywhere in the Bidwell Creek watershed. No evidence of channel movement was noted either on the aerial photographs or in the field. As well, there were no cases of excessive amounts of logging related large woody debris in the channel, and no sites with significant channel aggradation (a build-up of alluvial sediment due to increased sediment yield). A number of minor impacts were noted, that nevertheless could have at least local effects on water quality (see Table 5.4). All relate to active road crossings over the stream, and thus are likely the responsibility of the current licensee.

As indicated above, the Level 1 IWAP analysis indicated that changes in peak flow are a potential area of concern for the Lower Bidwell and Upper Bidwell sub-basins. Anecdotal evidence of increased water levels in the watershed has been provided from local residents. Increased water levels in the watershed are consistent with a large number of studies done on watersheds from around the world which show increases following forest harvest in both water yield (total volume of water flowing out of a watershed) and in peak flow. The threshold ECA for these changes to be detected is about 20%. Changes in peak flow do not appear to have had an impact on stream channel morphology or bank stability, but have reportedly impacted land use in the basin by raising the water table in a number of hay fields, thus reducing crop yields. These changes are a function of the watershed ECA, and are watershed scale phenomena. As such, the only mitigation is ECA reduction. Adherence to the Forest Practices Code of B.C. Act in any current or future forest harvest operation should be adequate to minimize future direct impacts on the stream channel network.

A fisheries habitat assessment was completed in the Bidwell Creek watershed, with the field work coinciding with the channel and riparian/wetland assessment field work. In general, there is excellent habitat for both spawning and rearing resident fish in the Bidwell Creek watershed. Sampling identified two species of fish, Rainbow trout and White sucker. Very healthy populations were found in several locations. Overall there have been few direct impacts on fisheries habitat from forest harvest. Adequate riparian buffers have been retained in most locations, no cases of excessive large woody debris were identified, and there are few examples of sediment being directly introduced to the stream. Mitigation of the channel impacts summarized in Table 5.4 along with routine road maintenance should be adequate to minimize direct fisheries habitat impacts from forestry activities.

A major factor impacting fish habitat and water quality within the Bidwell Creek watershed is beaver activity. There has been extensive tree and shrub harvesting of the riparian zone for construction of dams and lodges and for food. The removal of this riparian vegetation has reduced stream cover and exposed much of the channel to direct sunlight. The large number of beaver dams are preventing resident fish from accessing areas of the stream channel with spawning size gravels and other areas with potential rearing habitat.

Overall, water quality in Bidwell Creek presents few constraints to aquatic life production in the system. Results of a water quality survey conducted September 22-23, 1995 indicate that the waters of Bidwell Creek are low in total nutrients, but have alkalinity, conductivity, and total dissolved solids concentrations that are somewhat on the high side of typical values obtained from a large number of natural streams and rivers. Dissolved oxygen levels were adequate for the protection of early life stage cold water biota at all but one site, although the below-criteria value may be attributed to the long holding time before analysis.

Forest harvest may have had an effect on water quality. Increased leaching of cations is a possible outcome of the reduction in evapotranspiration that follows forest harvest. Although no pre-harvest water quality data is available, residents along Bidwell Creek have reported a significant decrease in potability.

There are relatively few road-related drainage, erosion, or stability concerns in the Bidwell creek watershed. However, the level of deactivation and the adequacy of deactivation efforts within the watershed are inconsistent, and there is no evidence that any deactivation features are being maintained. There are several roads which require level 2 road assessments. Most of the observed problems present a low risk to soil and water resources, and the urgency of required rehabilitation work is considered high for only two roads: E3 and E6.

Roads intersecting riparian and wetland habitats are producing adverse impacts at nine locations in the Bidwell watershed. The impacts are of two types: (1) loss of cover, nesting/denning, roosting and feeding sites for many wildlife species, (2) increased hunting access and enhanced vision and clear shooting range. The second impact type is more significant. Increased access results initially in increased harvest and ultimately in avoidance response and reduced population levels.

Ground cover restoration work for erosion control and forage production is not warranted. Because of FEN and wildlife tree considerations, it is recommended that wetland/riparian corridors at the nine impact areas be considered for revegetation prescription work. This work should focus on creation of wildlife tree patches of local poplar trees and other desirable wildlife habitat enhancing species, especially forage shrubs. This prescription work could be tied in with road restoration project development. Restoration planting will not be required at all nine of the impact locations, and consultation and further field assessment is needed to determine needs and preferred techniques.

The other mitigation consideration, access management, is beyond the scope of this assessment but access and FEN planning for the Bidwell landscape unit can provide valuable input to site restoration planning. This assessment has established that local wildlife resource users have serious concerns regarding road access to the high value wetland/riparian habitat areas and current and potential adverse effects of over-hunting on biodiversity and harvest levels.

The following recommendations are based on the results of the assessment program: