CLBWORKS-36: Mid-Columbia River Long-term Erosion Monitoring Program, 2016
Author: Kerr Wood Leidal
The primary objective of this program is to monitor shoreline erosion along the Columbia River in the region of influence of Revelstoke Dam, including operation of the fifth unit. This is to ensure that any incremental flows due to the five-unit operations do not impact the river banks in the area of influence. Specifically, the study will: - Identify shoreline areas susceptible to erosion (areas of concern) within the area, - Assess whether there are changes in the spatial extent of these areas of concern over the monitoring period, and - Assess whether any observed change in spatial extent is attributable to the operating regime of the fifth unit of Revelstoke Dam.
We do not have causal certainty between the implementation of a fifth unit at Revelstoke Dam and an impact on bank erosion. We conclude that (a) bank erosion is occurring, and (b) there is no increasing trend in erosion over the period of the study.
H10 cannot be addressed by this study as there were an insufficient number of years of baseline data collected prior to the start of operation of the fifth unit at Revelstoke Dam. This was identified at the beginning of the project. However post-Rev5 bank erosion rates are comparable or lower to pre-Rev5 bank erosion rates documented in another study (Table 4-3).
H20: Although erosion is occurring, there has been no consistent increase in erosion over the duration of the project (2010 to 2016) (Figure 3-3, Figure 3-6, Figure 3-7, Figure 3-8): we therefore accept H20. This is based on:
Erosion pin data:
– Of the 14 active sites:
o 1 site showed statistically significant deposition,
o 9 sites showed statistically significant erosion, and o 4 sites showed no statistically significant change.
– Erosion rates (2010 to 2016) ranged from about 1.5 cm/year to about 8.5 cm/year (Table 3-2).
– Deposition rate (2010 to 2016) was about 0.4 cm/year (Table 3-2).
– Average rate of change over all sites (2010 to 2016) was 3.1 cm/year (erosion).
River cross-section data:
– Of the 14 actives sites:
oUpper elevation band: 7 sites out of 14 showed statistically significant erosion, and 1 showed deposition (Table 3-5).
o Middle elevation band: 6 sites out of 14 showed statistically significant erosion, and none showed deposition (Table 3-6). o Lower elevation band: 4 sites out of 14 showed statistically significant erosion and 2 showed deposition (Table 3-7).
– Erosion rates (2010 to 2016) ranged from about 0.1 m/year to about 1.6 m/year (Table 3-5, Table 3-6, Table 3-7).
– Deposition rates (2010 to 2016) ranged from about 0.03 m/year to about 0.1 m/year.
– Average rate of change over all sites (2010 to 2016) was -0.21 m/year (erosion).
We do not have causal certainty between the implementation of a fifth unit at Revelstoke Dam and an impact on bank erosion. We conclude that (a) bank erosion is occurring, and (b) there is no increasing trend in erosion over the period of the study.
H10 cannot be addressed by this study as there were an insufficient number of years of baseline data collected prior to the start of operation of the fifth unit at Revelstoke Dam. This was identified at the beginning of the project. However post-Rev5 bank erosion rates are comparable or lower to pre-Rev5 bank erosion rates documented in another study (Table 4-3).
H20: Although erosion is occurring, there has been no consistent increase in erosion over the duration of the project (2010 to 2016) (Figure 3-3, Figure 3-6, Figure 3-7, Figure 3-8): we therefore accept H20. This is based on:
Erosion pin data:
– Of the 14 active sites:
o 1 site showed statistically significant deposition,
o 9 sites showed statistically significant erosion, and o 4 sites showed no statistically significant change.
– Erosion rates (2010 to 2016) ranged from about 1.5 cm/year to about 8.5 cm/year (Table 3-2).
– Deposition rate (2010 to 2016) was about 0.4 cm/year (Table 3-2).
– Average rate of change over all sites (2010 to 2016) was 3.1 cm/year (erosion).
River cross-section data:
– Of the 14 actives sites:
oUpper elevation band: 7 sites out of 14 showed statistically significant erosion, and 1 showed deposition (Table 3-5).
o Middle elevation band: 6 sites out of 14 showed statistically significant erosion, and none showed deposition (Table 3-6). o Lower elevation band: 4 sites out of 14 showed statistically significant erosion and 2 showed deposition (Table 3-7).
– Erosion rates (2010 to 2016) ranged from about 0.1 m/year to about 1.6 m/year (Table 3-5, Table 3-6, Table 3-7).
– Deposition rates (2010 to 2016) ranged from about 0.03 m/year to about 0.1 m/year.
– Average rate of change over all sites (2010 to 2016) was -0.21 m/year (erosion).
Resources Data:
Name: CLBWORKS-36-YR5-2017-05-01
Format: PDF
URL: https://www.bchydro.com/content/dam/BCHydro/customer-portal/documents/corporate/environment-sustainability/water-use-planning/southern-interior/clbworks-36-yr5-2017-05-01.pdf
Additional Info
Study Years: 2016, 2015, 2014, 2013, 2012, 2011, 2010, 2009
Published: 2017
Topics
Tags: Arrow Lakes Reservoir, CLBWORKS36, Deposition, Erosion, Erosion Monitoring, Middle Columbia RiverCLBWORKS-36: Mid-Columbia River Long-term Erosion Monitoring Program, 2016
Author: Kerr Wood Leidal
Tags: Arrow Lakes Reservoir, CLBWORKS36, Deposition, Erosion, Erosion Monitoring, Middle Columbia River
The primary objective of this program is to monitor shoreline erosion along the Columbia River in the region of influence of Revelstoke Dam, including operation of the fifth unit. This is to ensure that any incremental flows due to the five-unit operations do not impact the river banks in the area of influence.
Specifically, the study will:
- Identify shoreline areas susceptible to erosion (areas of concern) within the area,
- Assess whether there are changes in the spatial extent of these areas of concern over the monitoring period, and
- Assess whether any observed change in spatial extent is attributable to the operating regime of the fifth unit of Revelstoke Dam.
Summary
We do not have causal certainty between the implementation of a fifth unit at Revelstoke Dam and an impact on bank erosion. We conclude that (a) bank erosion is occurring, and (b) there is no increasing trend in erosion over the period of the study.
H10 cannot be addressed by this study as there were an insufficient number of years of baseline data collected prior to the start of operation of the fifth unit at Revelstoke Dam. This was identified at the beginning of the project. However post-Rev5 bank erosion rates are comparable or lower to pre-Rev5 bank erosion rates documented in another study (Table 4-3).
H20: Although erosion is occurring, there has been no consistent increase in erosion over the duration of the project (2010 to 2016) (Figure 3-3, Figure 3-6, Figure 3-7, Figure 3-8): we therefore accept H20. This is based on:
Erosion pin data:
– Of the 14 active sites:
o 1 site showed statistically significant deposition,
o 9 sites showed statistically significant erosion, and o 4 sites showed no statistically significant change.
– Erosion rates (2010 to 2016) ranged from about 1.5 cm/year to about 8.5 cm/year (Table 3-2).
– Deposition rate (2010 to 2016) was about 0.4 cm/year (Table 3-2).
– Average rate of change over all sites (2010 to 2016) was 3.1 cm/year (erosion).
River cross-section data:
– Of the 14 actives sites:
oUpper elevation band: 7 sites out of 14 showed statistically significant erosion, and 1 showed deposition (Table 3-5).
o Middle elevation band: 6 sites out of 14 showed statistically significant erosion, and none showed deposition (Table 3-6). o Lower elevation band: 4 sites out of 14 showed statistically significant erosion and 2 showed deposition (Table 3-7).
– Erosion rates (2010 to 2016) ranged from about 0.1 m/year to about 1.6 m/year (Table 3-5, Table 3-6, Table 3-7).
– Deposition rates (2010 to 2016) ranged from about 0.03 m/year to about 0.1 m/year.
– Average rate of change over all sites (2010 to 2016) was -0.21 m/year (erosion).