Appendix - 123445 & 123446 - Tyhee Creek
Site Location
PSCIS crossing 123445 is located on Tyhee Creek on Highway 16 approximately 2km south of Telkwa, BC. The highway is located approximately 170m upstream from the confluence with the Bulkley River. PSCIS crossing 123446 is located on Tyee Lake Road approximately 540m upstream of Highway 16. Both crossings are the responsibility of the Ministry of Transportation and Infrastructure.
Background
At crossing 123445, Tyhee Creek is a third order stream with a watershed area upstream of the crossing of approximately 35km2. The elevation of the watershed ranges from 1000m to 520m at the highway. Numerous fish species have been documented upstream of both crossings including sucker (general), longnose sucker, minnow (general), northern redbelly dace, peamouth chub, northern pikeminnow, redside shiner, burbot, salmon (general), cutthroat trout, pink salmon, chum salmon, coho salmon, rainbow trout, steelhead, sockeye salmon, chinook salmon, giant pygmy whitefish, pygmy whitefish, mountain whitefish, sculpin (general), and prickly sculpin (MoE 2020a).
Tyhee Lake is located approximatley 800m upstream of crossing 123446. Tyhee Lake has a surface area of 3.18km2, a mean depth of 11.1m, a maximum depth of 22.2m and a mean water retention time estimated at 5 years (Reavie et al. 2000). Reavie et al. (2000) report that Tyhee Lake was a naturally productive system that has experienced moderate eutrophication over time due to adjacent land use. In response to concerns expressed by the Tyhee Lake Protection Society, a management plan was drafted for the lake in 1999 with the objective of slowing down or eliminating eutrophication (Rysavy et al. 1999). Fish passage issues at the highway have also been highlighted by the protection society in the past (Hatlevik 1992). Cutthrout trout have been observed unsuccessfully attempting to ascend into the culvert at the highway (pers comm Mike Ridsdale, Environmental Assessment Coordinator - Office of the Wet’suwet’en). Tyhee Lake has been stocked with rainbow trout since 1955, with stocking events occuring annual since 1990 (BC Ministry of Environment 2021).
There are five tributaries that flow into the lake from the east and north with all systems containing crossings previously inventoried as barriers or potential barriers.
PSCIS stream crossings 123445 and 123446 were rated high priorities for follow up by Wilson and Rabnett (2007) and Irvine (2018) due to significant quantities of lake habitat upstream and historical records of steelhead and salmon upstream. A map of the watershed is provided in mapsheet attachment 093L.118.
Stream Characteristics at Crossings 123445 and 123446
At the time of the survey, crossing 123445 on Highway 16 was un-embedded, non-backwatered and a barrier to upstream fish passage. Downcutting of the downstream area was apparent and due likely to high flow velocities through the pipes during elevated flow events. The pipes were 0.9m in diameter with lengths of 50m, a culvert slope of 3%, a stream width ratio of 3.1 and an outlet drop of 0.9m (Table 5.9). Water temperature was 11\(^\circ\)C, pH was 8.1 and conductivity was 418uS/cm.
Crossing 123446 on Tyee Lake Road was un-embedded, 10% backwatered and classified as a barrier to upstream fish passage. The pipe was 1.85m in diameter with a length of 21m, a culvert slope of 1.1%, a stream width ratio of 1.4 and an outlet drop of 0m (Table 5.10).
Stream Characteristics Downstream of 123445
The stream was surveyed downstream from the culvert for 170m to the confluence with the Bulkley River (Figures 5.10 - 5.11). Flows were very low at the time of the survey and the stream channel went subsurface near the Bulkley River floodplain. Overall, total cover amount was rated as moderate with overhanging vegetation dominant. Cover was also present as small woody debris, large woody debris, boulders, and undercut banks (Table 5.12). The average channel width was 2.8m, the average wetted width was 1.5m and the average gradient was 3%. The dominant substrate was cobbles with boulders subdominant. Some gravels suitable for spawning were observed and unidentified fry/juvenile fish (3 @ 50mm, and 1 @ 90mm) were observed. Habitat value was rated as moderate as it was considered an important migration corridor with moderate value habitat for fry/juvenile salmonid rearing.
Stream Characteristics Upstream of 123445 and downstream of 123446
The stream was surveyed from 123445 for 540m to 123446(Figures 5.12 - 5.13). Within the area surveyed, total cover amount was rated as moderate with overhanging vegetation dominant. Cover was also present as small woody debris, large woody debris, undercut banks, and instream vegetation (Table 5.12). The average channel width was 2.1m, the average wetted width was 1.6m and the average gradient was 0.5%. Water within the narrow channel was noted as often stagnant with aquatic vegetation present throughout. Some riparian disturbance by adjacent livestock was also noted. Although, habitat value was considered of low value for rearing and spawning it was rated as moderate overall as it was considered an important migration corridor providing access to the lake.
Stream Characteristics Upstream of 123446
Tyhee Creek was surveyed upstream from 123446 for 100m with the survey discontinued due to difficult survey conditions within the wetland type habitat and the presence of fenced private land (Figures 5.14 - 5.15). Within the area surveyed, total cover amount was rated as abundant with overhanging vegetation dominant. Cover was also present as small woody debris, large woody debris, deep pools, and instream vegetation (Table 5.12). The average channel width was 8.5m, the average wetted width was 7.5m and the average gradient was 0.2%. Beaver activity was prevalent in the area surveyed and there was a large agricultural field located on the right bank of the stream. Habitat value was rated as moderate as it was considered an important migration corridor providing access to the lake.
Crossing 123463 is located on Victor Creek and Tyhee Lake Road. Victor Creek flows into the east side of Tyhee Lake approximately 1.7km upstream from the mouth. At the time of the survey, the round culvert appeared to have been recently replaced. The structure was un-embedded, non-backwatered and considered a barrier to upstream fish passage according to the provincial protocol. The pipe was 0.6m in diameter with a length of 18m, a culvert slope of 3%, a stream width ratio of 3.1 and an outlet drop of 0m (Table 5.11).
Table 5.13 presents preliminary fish passage modelling data for crossing 123445 with spawning and rearing habitat estimated for chinook, coho, sockeye and steelhead. Modelled estimates of the total length of salmon or steelhead habitat upstream of the crossing before potential barriers are 0.5km of potential spawning habitat and 0.5km of potential rearing habitat. Table 5.14 presents preliminary fish passage modelling data for crossing 123446 with spawning and rearing habitat estimated for chinook, coho, sockeye and steelhead. Modelled estimates of the total length of salmon or steelhead habitat upstream of the crossing before potential barriers are 0.8km of potential spawning habitat and 12.3km of potential rearing habitat.
Structure Remediation and Cost Estimate
Structure replacement with bridges for 123445 (25m span) and 123446 (10m span) could be considered to provide access to the habitat located upstream. An estimate of cost for replacement of 123445 is $18,750,000 and $2,000,000 for 123446.
Conclusion
As Tyhee Lake is located upstream of both crossings surveyed with steelhead and mulitple salmon species historically recorded upstream of the highway, the restoration of fish passage at 123445 was rated as a moderate priority for proceeding to design for replacement. Although classified as a barrier to upstream fish passage according to the provincial protocol, crossing 123446 appeared likely passable for resident, fluvial and anadromous adult salmonids migrating to Tyhee Lake if passage to above the highway was facilitated. Crossing 123446 was ranked as a high priority for proceeding to design for replacement. Adjacent land use has been documented as negatively impacting fish habitat values in the watershed and the multiple strategies to quantify and reduce those impacts noted in Rysavy et al. (1999) should be considered alongside restorative works addressing fish passage in the watershed.
| Location and Stream Data |
|
Crossing Characteristics | – |
|---|---|---|---|
| Date | 2020-08-29 | Crossing Sub Type | Round Culvert |
| PSCIS ID | 123445 | Diameter (m) | 0.9 |
| External ID | – | Length (m) | 50 |
| Crew | KP, AI | Embedded | No |
| UTM Zone | 9 | Depth Embedded (m) | – |
| Easting | 627238 | Resemble Channel | No |
| Northing | 6061456 | Backwatered | No |
| Stream | Tyhee Creek | Percent Backwatered | – |
| Road | Highway 16 | Fill Depth (m) | 8 |
| Road Tenure | MoTi unclassified | Outlet Drop (m) | 0.9 |
| Channel Width (m) | 2.8 | Outlet Pool Depth (m) | 0.42 |
| Stream Slope (%) | 3 | Inlet Drop | No |
| Beaver Activity | No | Slope (%) | 3 |
| Habitat Value | Medium | Valley Fill | Deep Fill |
| Final score | 42 | Barrier Result | Barrier |
| Fix type | Replace with New Open Bottom Structure | Fix Span / Diameter | 25 |
Photos: From top left clockwise: Road/Site Card, Barrel, Outlet, Downstream, Upstream, Inlet.
|
|||
| Comments: Important migration corridor to Tyee Lake. Large outlet drop seems unliklely passabel by any life stage or species. |
| Location and Stream Data |
|
Crossing Characteristics | – |
|---|---|---|---|
| Date | 2020-08-29 | Crossing Sub Type | Round Culvert |
| PSCIS ID | 123446 | Diameter (m) | 1.85 |
| External ID | – | Length (m) | 21 |
| Crew | AI, KP | Embedded | No |
| UTM Zone | 9 | Depth Embedded (m) | – |
| Easting | 627527 | Resemble Channel | No |
| Northing | 6061771 | Backwatered | Yes |
| Stream | Tyhee Creek | Percent Backwatered | 10 |
| Road | Tyee Lake Road | Fill Depth (m) | 1.3 |
| Road Tenure | MoTi highway | Outlet Drop (m) | 0 |
| Channel Width (m) | 2.5 | Outlet Pool Depth (m) | 0.1 |
| Stream Slope (%) | 0.5 | Inlet Drop | No |
| Beaver Activity | Yes | Slope (%) | 1.1 |
| Habitat Value | Medium | Valley Fill | Deep Fill |
| Final score | 24 | Barrier Result | Barrier |
| Fix type | Replace with New Open Bottom Structure | Fix Span / Diameter | 10 |
Photos: From top left clockwise: Road/Site Card, Barrel, Outlet, Downstream, Upstream, Inlet.
|
|||
| Comments: Important migration corridor to get to Tyee Lake from Bulkley River. Crossing does not appear to be barrier to most life stages/species at most flows. |
| Location and Stream Data |
|
Crossing Characteristics | – |
|---|---|---|---|
| Date | 2020-08-29 | Crossing Sub Type | Round Culvert |
| PSCIS ID | 123463 | Diameter (m) | 0.6 |
| External ID | – | Length (m) | 18 |
| Crew | AI, KP | Embedded | No |
| UTM Zone | 9 | Depth Embedded (m) | – |
| Easting | 627570 | Resemble Channel | No |
| Northing | 6064562 | Backwatered | Yes |
| Stream | Victor Creek | Percent Backwatered | 30 |
| Road | Tyee Lake Road | Fill Depth (m) | 1 |
| Road Tenure | MoTi local | Outlet Drop (m) | 0 |
| Channel Width (m) | 1.8 | Outlet Pool Depth (m) | 0.3 |
| Stream Slope (%) | 1 | Inlet Drop | No |
| Beaver Activity | No | Slope (%) | 3 |
| Habitat Value | Medium | Valley Fill | Deep Fill |
| Final score | 29 | Barrier Result | Barrier |
| Fix type | Replace Structure with Streambed Simulation CBS | Fix Span / Diameter | 5 |
Photos: From top left clockwise: Road/Site Card, Barrel, Outlet, Downstream, Upstream, Inlet.
|
|||
| Comments: No habitat confirmation conducted in 2020. Newly replaced crossing. ID# 8 21 18 01 . |
| Site | Location | Length Surveyed (m) | Channel Width (m) | Wetted Width (m) | Pool Depth (m) | Gradient (%) | Total Cover | Habitat Value |
|---|---|---|---|---|---|---|---|---|
| 123445 | Downstream | 170 | 2.8 | 1.5 | – | 3 | moderate | moderate |
| 123445 | Upstream | 540 | 2.1 | 1.6 | – | 0.5 | moderate | moderate |
| 123446 | Upstream | 100 | 8.5 | 7.5 | 0.8 | 0.2 | abundant | moderate |
| Habitat | Potential | Remediation Gain | Remediation Gain (%) |
|---|---|---|---|
| Salmon Network (km) | 20.6 | 0.5 | 2 |
| Salmon Lake Reservoir (ha) | 367.3 | 0.0 | 0 |
| Salmon Wetland (ha) | 9.7 | 0.0 | 0 |
| Steelhead Network (km) | 20.9 | 0.5 | 2 |
| Steelhead Lake Reservoir (ha) | 367.3 | 0.0 | 0 |
| Steelhead Wetland (ha) | 9.7 | 0.0 | 0 |
| CH Spawning (km) | 0.8 | 0.5 | 62 |
| CH Rearing (km) | 2.2 | 0.5 | 23 |
| CO Spawning (km) | 1.3 | 0.5 | 38 |
| CO Rearing (km) | 2.2 | 0.5 | 23 |
| CO Rearing (ha) | – | – | – |
| SK Spawning (km) | 1.3 | 0.5 | 38 |
| SK Rearing (km) | 10.6 | 0.0 | 0 |
| SK Rearing (ha) | 367.3 | – | – |
| ST Spawning (km) | 0.8 | 0.5 | 62 |
| ST Rearing (km) | 2.5 | 0.5 | 20 |
| All Spawning (km) | 1.3 | 0.5 | 38 |
| All Rearing (km) | 13.0 | 0.5 | 4 |
| All Spawning and Rearing (km) | 13.0 | 0.5 | 4 |
| * Model data is preliminary and subject to adjustments including incorporating area based estimates. | |||
| † Modelled rearing habitat estimates include linear lengths of centrelines within wetlands for coho and within lakes >100ha (multiplied by 1.5) for sockeye. | |||
| ‡ Remediation Gain is an estimate of the amount of habitat to be gained by providing access above the crossing. This assumes that all upstream habitat is currently unavailable and that all modelled unassessed crossings located upstream would prevent further passage. |
| Habitat | Potential | Remediation Gain | Remediation Gain (%) |
|---|---|---|---|
| Salmon Network (km) | 20.2 | 10.1 | 50 |
| Salmon Lake Reservoir (ha) | 367.3 | 367.3 | 100 |
| Salmon Wetland (ha) | 9.7 | 0.0 | 0 |
| Steelhead Network (km) | 20.4 | 10.1 | 50 |
| Steelhead Lake Reservoir (ha) | 367.3 | 367.3 | 100 |
| Steelhead Wetland (ha) | 9.7 | 0.0 | 0 |
| CH Spawning (km) | 0.3 | 0.3 | 100 |
| CH Rearing (km) | 1.7 | 1.7 | 100 |
| CO Spawning (km) | 0.8 | 0.8 | 100 |
| CO Rearing (km) | 1.7 | 1.7 | 100 |
| CO Rearing (ha) | – | – | – |
| SK Spawning (km) | 0.8 | 0.8 | 100 |
| SK Rearing (km) | 10.6 | 10.6 | 100 |
| SK Rearing (ha) | 367.3 | – | – |
| ST Spawning (km) | 0.3 | 0.3 | 100 |
| ST Rearing (km) | 2.0 | 1.7 | 85 |
| All Spawning (km) | 0.8 | 0.8 | 100 |
| All Rearing (km) | 12.6 | 12.3 | 98 |
| All Spawning and Rearing (km) | 12.6 | 12.3 | 98 |
| * Model data is preliminary and subject to adjustments including incorporating area based estimates. | |||
| † Modelled rearing habitat estimates include linear lengths of centrelines within wetlands for coho and within lakes >100ha (multiplied by 1.5) for sockeye. | |||
| ‡ Remediation Gain is an estimate of the amount of habitat to be gained by providing access above the crossing. This assumes that all upstream habitat is currently unavailable and that all modelled unassessed crossings located upstream would prevent further passage. |
Figure 5.10: Typical habitat downstream of PSCIS crossing 123445.
Figure 5.11: Typical habitat downstream of PSCIS crossing 123445.
Figure 5.12: Habitat upstream of PSCIS crossing 123445.
Figure 5.13: Habitat upstream of PSCIS crossing 123445.
Figure 5.14: Habitat upstream of PSCIS crossing 123446.
Figure 5.15: Habitat upstream of PSCIS crossing 123446.