Fish Habitat Structure Monitoring in Pass (Norns) Creek 2013

Transcription

1 Fish Habitat Structure Monitoring in Pass (Norns) Creek 2013 Prepared by: Natasha Audy Michael Zimmer Okanagan Nation Alliance Old Okanagan Highway Westbank, BC V4T 3L7 Phone: (250) Fax: (250) Prepared for: Trevor Oussoren Fish & Wildlife Compensation Program Columbia Basin th Street Castlegar, B.C. V1N 2N1 Prepared with financial support of: the Fish and Wildlife Compensation Program on behalf of its program partners BC Hydro, the Province of BC, Fisheries and Oceans Canada, First Nations and the public. March 2015

2 Table of Contents 1.0 Introduction Structure Stability and Functioning Methods Results Fish Use Methods Results Conclusions and Recommendations Acknowledgments References List of Tables Table 1. Summary of structure stability and recommendations Table 2. Summary of fish observed in Norns Creek surrounding the given structures, during August 22, 2013 snorkel count Table 3. Summary of observed fish by species in Norns Creek, in Pass Creek Regional Park Table 4. Summary of Rainbow trout observations by length in Norns Creek, in Pass Creek Regional Park List of Figures Figure 1. Air photo overview of the section of Pass (Norns) Creek where the fish habitat structures are located (source: Google Earth 2014) Figure 2. Air photo overview of location of fish habitat structures in Pass Creek, Newbury weir and slumped bank. (source: Google Earth 2014)... 4 Figure 3. Structure 7, looking downstream. This structure was destroyed by high water events. This structure received a 100 rating Figure 4. Close-up of sheared cables and exposed nails located on Structure

3 Figure 5. Close-up of loosened cables located on Structure Figure 6. Structure 14, looking downstream. This structure received an "M" rating (minor rotation or movement of individual logs or rocks). Note the accumulation of SWD on the upstream side of the structure Figure 7. Close-up of SWD accumulation on the upstream side of Structure Figure 8. Structure 18, looking upstream. This structure had a build-up of sediment Figure 9. Newbury weir, looking downstream Figure 10. Slumped bank and failed riprap treatment adjacent to the Regional Fair Grounds, Pass Creek Regional Park, Figure 11. Close-up of slumped bank adjacent to Fair Grounds, Pass Creek Regional Park, August Appendices Appendix A Structure Photos 2

4 1.0 Introduction Pass Creek is a low gradient (<2%), moderate sized creek (bankful width of 10-15m) in the first reach, above the confluence with the Columbia River. It is accessible from the Columbia River for 2.2 km where an impassable falls restricts upstream fish movement. Pass Creek is the first major (5th order) tributary to the Columbia River, downstream from Hugh Keenleyside Dam, near Castlegar (Figure 1). Pass Creek supports important spawning and rearing habitat for Columbia River rainbow trout, kokanee and mountain whitefish. The Pass Creek alluvial fan, at the confluence with the Columbia River is extensive and also supports an important spawning habitat for Columbia River rainbow trout (Thorley and Baxter 2012). Figure 1. Air photo overview of the section of Pass (Norns) Creek where the fish habitat structures are located (source: Google Earth 2014). Instream cover in the form of log jams was sparse up until log and rock habitat enhancement structures were constructed from Pass Creek Regional Park, downstream to Broadwater Road during the period (McCleary 1999; Zimmer 2000; Zimmer 2002). Rainbow trout fry counts around 2001 built structures was the last time fry use was directly observed (Zimmer 2002). There are no records of detailed stability and functioning assessments completed on the habitat structures since the last construction phase in 2001 (S. Arndt 2012, FWCP Biologist, pers. comm.). During the 2011 rainbow trout spawning season, 774 redds were identified in the 2.2 km 3

5 between Pass (Norns) Creek fan (Columbia confluence) and an impassable falls (Thorley and Baxter 2012), indicating that the lower section of Pass Creek continues to be important spawning and rearing habitat to Columbia River fishes. Project objectives are as follows: (1) Examine (monitor) each of the structures built since 1998 for stability and function. (2) Examine rainbow trout fry use by snorkelling/visual observation. Monitoring was conducted in August 2013 to document stability and functioning of 18 compensatory fish habitat structures built in in Pass (Norns) Creek, near the Pass Creek Campground and Fair Grounds (Figure 2). No stability assessments have been conducted since final construction in High flows in 2012 may have influenced structure stability, and supported a heightened interest to revisit these structures. The monitoring of the structures included: a physical examination of cabling/anchoring points, structure/element movement; and fish use. Fish use was conducted with the assistance of Steve Arndt. The following sections describe the findings of the monitoring program. Figure 2. Air photo overview of location of fish habitat structures in Pass Creek, Newbury weir and slumped bank. (source: Google Earth 2014) 4

6 2.0 Structure Stability and Functioning 2.1 Methods Each of the structures built since 1998, were examined and photo-documented from a number of different perspectives, depending on the structure. Structures were examined for condition of anchoring cables and degree of shifting away from the bank as per Miles (1995) proposed assessment methodologies. The numbers of slipped and broken cables were noted and recommendations have been developed for each structure. Close-up photos of frayed and sheared cables, as well as small woody debris (SWD) accumulation were also taken. Structures were examined for movement, with care taken to note shifted, rotated, missing, displaced, and/or buried logs and boulders. All cable anchoring points (to boulders, and between log elements) were examined among the 18 fish habitat structures (those engineered and comprised of rock and large wood elements). Structure stability was compared against Miles (1995) suggested framework for determining decreased stability: N no movement or adverse change; M minor movement or rotation of individual rocks or logs; 25 ¼ of rocks or logs moved, missing or buried; 50 ½ of rocks or logs moved, missing or buried; 75 ¾ of rocks or logs moved, missing or buried; 100 all rocks or logs moved, missing or buried; and The Newbury weir was also examined and photo-documented. 2.2 Results The majority of structures showed signs of shifting, rotation, and a number had broken, frayed or sheared cables (Figures 4-8; Table 1). Seven of the 18 structures had either logs or boulders (or both) partially or completely buried. Additionally, six of the structures have large exposed nails (from the original attachment of small woody debris (SWD) to the structure at the time of structure installation), which are a potential hazards (e.g., Figure 4). Each of the structures was photo documented, with photos provided in Appendix A. 5

7 Figure 3. Structure 7, looking downstream. This structure was destroyed by high water events. This structure received a 100 rating. Figure 4. Close-up of sheared cables and exposed nails located on Structure 12. 6

8 Figure 5. Close-up of loosened cables located on Structure 13. Figure 6. Structure 14, looking downstream. This structure received an "M" rating (minor rotation or movement of individual logs or rocks). Note the accumulation of SWD on the upstream side of the structure. 7

9 Figure 7. Close-up of SWD accumulation on the upstream side of Structure 14. Figure 8. Structure 18, looking upstream. This structure had a build-up of sediment. 8

10 Table 1. Summary of structure stability and recommendations. Structure Rating Comments Maintenance Required? Recommendations Structure 1 M cables have loosened, but are otherwise good; 2 boulders buried No stable and functioning Structure 2 25 boulders buried; cables are in good condition; SWD accumulation underneath No stable and functioning Structure 3 75 buried log and rootwad; affected by high water; however, structure creates a deep pool with structure 4 Yes stable and functioning Structure 4 50 candidate for maintenance; boulders (3) are no longer attached; rotated and snapped cables Yes remove broken cables; additional rock recommended for placement upstream, along eroding bank Structure buried logs; a lot of accumulated SWD; loose cable at end of structure Yes consider repositioning structure Structure 6 M relatively stable; large dogwood growing over part of structure; exposed nails are a hazard Yes stable and functioning; remove exposed nails Structure structure originally placed to encourage sediment deposition and channel narrowing. Structure displaced structure, origin unknown; could potentially reposition this structure; Yes Yes stable and functioning consider relocating structure; remove exposed nails

11 Structure Rating Comments exposed nails are a hazard Maintenance Required? Recommendations Structure displaced structure; loose cables on one log; exposed nails are a hazard Yes consider relocating structure; remove exposed nails Structure displaced structure Yes consider relocating structure Structure 11 M SWD accumulating throughout structure; structure looks as though it's been pulled away from bank or significant erosion has occurred; 1 cable starting to fray; exposed nails are a hazard Yes stable and functioning; remove exposed nails; opportunity for riparian planting should be investigated. Structure 12 M broken cables; SWD accumulation; exposed nails are a hazard Yes remove broken cables and exposed nails Structure broken cables (2); 1 very loose cable; exposed nails are a hazard Yes remove broken cables and exposed nails Structure 14 M front rootwad is buried; cables appear to be secure; exposed nails are a hazard Structure 15 N LWD stacked on top of structure; structure appears to be in good shape and functional Yes No stable and functioning; remove exposed nails stable and functioning; no maintenance required Structure 16 M buried cable; broken cable Yes remove broken cable Structure buried cables; one cable loop no longer holding anything Yes remove loose cable 10

12 Structure Rating Comments Maintenance Required? Recommendations Structure lots of sediment buildup; buried boulders and logs; cottonwood down upstream of structure, enhancing effect of structure No stable and functioning; no maintenance required Newbury Weir 75 has been scoured down to native rock (cobbles); angular material has moved downstream 10-25m No Still functioning as fry and juvenile cover; continue to monitor 11

13 As noted in Table 1, of the 18 structures, four do not require any maintenance, seven require minor maintenance (such as removing loose/broken cables or removing exposed nails), and seven require major maintenance (such as structure relocation or removal). The Newbury weir was also examined and photo-documented (Figure 9). It was found that the weir has been scoured down to native rock, with the majority of the angular material moved 10 to 25 metres downstream. The recommendation is to continue to monitor the weir, but not to do any maintenance at this time. Figure 9. Newbury weir, looking downstream. Of particular note was the riprap bank treatment adjacent to the Fair Ground / Rodeo grounds. This site was identified by the Regional District of Central Kootenay (RDCK, C. Gaynor, pers com.) to Steve Arndt in 2013 as an area of particular concern (see Figures 10 and 11), located between Structures 4 and 5. This site is noted as having two erosion scars where the riprap treatment has failed, and is in priority need of treatment to reduce the risk of further erosion, and lateral creek movement. If the bank is to be treated, it is also a good candidate for fish habitat enhancements along the toe of the structure (i.e., boulder clusters). Any works proposed or planned in this location should be undertaken in partnership with the RDCK.

14 Figure 10. Slumped bank and failed riprap treatment adjacent to the Regional Fair Grounds, Pass Creek Regional Park, Figure 11. Close-up of slumped bank adjacent to Fair Grounds, Pass Creek Regional Park, August

15 3.0 Fish Use 3.1 Methods Fish use was monitored by snorkelling the structures during summer (Aug 22, 2013). A two person snorkel team comprised of an ONA Biologist and Technician floated the section of Norns Creek with the fish habitat enhancement structures. Individual fish, with an emphasis on Rainbow Trout fry, were tallied per section adjacent to each structure, and summarized. A similar approach has been taken on other fish habitat construction projects (e.g., Salmo River, Zimmer 2012). Each person observed one half of the creek, tallying fish observed. Fish were identified by species and categorized by length. As the float took place in late August when lower flows are typical, some sections of the creek were challenging to snorkel as there were a number of areas with insufficient water to facilitate snorkelling. Fish observed included Rainbow Trout (RB), Kokanee (KO), sculpin (CC), Mountain Whitefish (MW), and other, or unknown minnows (cyprinids) (Table 2). 3.2 Results Table 2. Summary of fish observed in Pass Creek surrounding the given structures, during August 22, 2013 snorkel count. Location RB MW KO CC fry 10-20cm 20-30cm 30+cm (juveniles) unknown 1 Structure Structures 16 & upstream of Newbury Weir Newbury Weir upstream of Structures 13 & Structures 13 & * 2 1** 7 Bend *** Structures 9 & Structures 5 & upstream of Structure **** Structure 4 downstream Side Channel *** Pool/Glide *** 0 0 Total * 2 live sculpin, 1 dead sculpin (12 anal rays, smooth scales); ** unknown minnow species *** dead **** observed by structure 14

16 A total of 1783 rainbow trout were observed during the snorkel count. Of those, 84% were identified as fry, 14% were identified as being in the 10-20cm size range, and 1% were identified as being in the 20-30cm size range (Table 4). Table 3. Summary of observed fish by species in Norns Creek, in Pass Creek Regional Park Species Total (n) Relative Percent (%) Rainbow Trout Kokanee Sculpin spp Mountain Whitefish Unknown Total Table 4. Summary of Rainbow trout observations by length in Norns Creek, in Pass Creek Regional Park Life Stage Total (n) Relative Percent (%) fry cm cm cm Total Conclusions and Recommendations In a general, the fish habitat structures that have been installed in Pass Creek since 1998 have weathered fairly well, and function as fry and young-of-the-year Rainbow Trout cover habitat. However, high flows in 2012 and 2013 may have played a role in shifting and stressing the structures. The majority of the structures are now in need of maintenance with an emphasis on relocating structures, removing loose cables and removing exposed nails/spikes. The slumping bank identified during the surveys of the structures should be further assessed to determine next steps including maintenance and fish habitat improvements, as an emphasis of a proposal and conditionally approved project for Pass Creek Park for

17 The Newbury weir should continue to be monitored on an annual basis to ensure that it is still providing cover for fry and juvenile Rainbow Trout, and other fishes. 5.0 Acknowledgments This Project is funded by the Fish and Wildlife Compensation Program on behalf of its program partners BC Hydro, the Province of B.C., First Nations and the public, who work together to conserve and enhance fish and wildlife impacted by the construction of BC Hydro dams. We also wish to recognize the support and review of Trevor Oussoren (FWCP) and Steve Arndt (MFLNRO). 6.0 References McCleary, R Norns Creek Fish Habitat Enhancement Project. Prepared for the Columbia Basin Fish & Wildlife Compensation Program. Miles, M On the difficulty of restoring fisheries habitat in impacted gravel bed rivers: case studies from the Coquihalla Highway and other areas of Northwestern North America. In Proceedings: The gravel-bed rivers IV workshop-gravel-bed rivers in the environment. Thorley, J.L. and J.T.A. Baxter WLR Monitoring Study No. CLBMON-46 (Year 4), Lower Columbia River Rainbow Trout Spawning Assessment, Study Period: January to July Prepared for BC Hydro, Castlegar, BC. Zimmer, M Norns Creek Fish Habitat Enhancement. Prepared for the Columbia Basin Fish & Wildlife Compensation Program. Zimmer, M Norns Creek Fish Habitat Enhancement Summary for Prepared for the Columbia-Kootenay Fisheries Renewal Partnership. Zimmer, M Salmo River Fish Habitat Compensation Monitoring Year 1 post-construction (2011). Prepared for FortisBC-Gas, Surrey, BC. 16

18 Appendix A Structure Photos Structure 1, looking upstream, August 15, Structure 2, looking upstream, August 15, Structure 1, looking downstream, August 15, Structure 2, looking downstream, August 15, 2013.

19 Appendix A Structure Photos Structure 3, looking upstream, August 15, Structure 4, looking across the stream, August 15, Structure 3, looking downstream, August 15, Structure 5, looking upstream, August 15, 2013.

20 Appendix A Structure Photos Structure 5, looking across the stream, August 15, Structure 6, looking downstream (can see slumped bank in the background on the left), August 15, Structure 6, View upstream, August 15, Structure 7, standing on bank, August 15, 2013.

21 Appendix A Structure Photos Structure 8, looking downstream, August 15, Structure 9, looking across the stream, August 15, Structure 8, looking upstream, August 15, Structure 9, looking upstream, August 15, 2013.

22 Appendix A Structure Photos Structure 10, view into the bank, August 15, 2013 Structure 11, view into the bank, August 15, Structure 10, from shore, angled downstream, August 15, Structure 11, looking upstream, August 15, 2013.

23 Appendix A Structure Photos Structure 12, view into the bank, August 15, Structure 13, looking upstream, August 15, Structure 12, looking downstream, August 15, Structure 13, looking downstream, August 15, 2013.

24 Appendix A Structure Photos Structure 14, looking across, angled downstream, August 15, Structure 15, looking downstream, August 15, Structure 15, looking into the bank, August 15, Structure 16, looking upstream, August 15, 2013.

25 Appendix A Structure Photos Structure 16, looking across, rock diversion evident on the left. August 15, Structure 17, view from the bank, August 22, Structure 17, view into the bank, August 22, Structure 18, looking downstream. Naturally fallen cottonwood evident on the left of the photo. August 22, 2013.

26 Appendix A Structure Photos