The effects of mainstem flow, water velocity and spill on salmon and steelhead populations of the Columbia River Columbia River Inter Tribal Fish Commission October 12, 2006 Jerry McCann and Margaret Filardo Fish Passage Center 2006 files/141.ppt
A Hydrographic Perspective
Historic and Present Flow 500 Discharge at Bonneville Dam (kcfs) 450 400 350 300 250 200 150 100 50 Post Development (kcfs) Pre-Development (kcfs) 0 Aug Sep Oct Nov Dec Jan Feb Mar Apr May June July Month
Historic and Present Water Travel Times (Volume/Flow) 45.0 40.0 Water Travel Time (days) 35.0 30.0 25.0 20.0 15.0 10.0 5.0 Snake Lew to BVL Methow R to BVL Snake/Col Biop Flow s Mid Col/Col Biop Flow s 0.0 1929 1939 1949 1959 1969 1979 1989 1999
Likelihood of Meeting Biological Opinion Flow Objectives Under Current Operations 100% 90% Percentage of 50 Year 80% 70% 60% 50% 40% 30% 20% 10% 0% April 1-15 April 16-30 May June July August Time Period Lower Granite Priest Rapids McNary
Estimated Travel Time for wild Chinook from the Salmon River to the Mouth of the Columbia River (derived from Raymond 1979) Travel Time (Days) 60 50 40 30 20 10 0 Low Flow Moderate Flow pre-dam post-dam
Smolt migration: Why focus on flow and spill? Mechanisms: Flow affects: Time to estuary; Temperature exposure; Energy reserves and stress; Timing of salt-water entry; Estuary plume. Spill affects: Spill reduces project mortality by avoiding turbine passage; Spill reduces passage delay; Predator avoidance; Spill allows juvenile migrants to avoid adverse conditions such as high water temperatures; Spill results in reduced cumulative passage effects leads to reduced delayed mortality.
Measurements: Travel Time; Direct survival (estimated by inriver or reach survival); Delayed mortality (related to fish condition, not observed directly).
Juvenile Salmon Analyses Travel Time and Survival
S/S Lower Granite Smoltsperspawner Freshwater Harvest & Adult dam passage Little Goose Monumental Ice Harbor McNary John Day The Dalles Bonneville Direct survival through dams Direct survival transported fish R/S Estuary SAR Ocean
Influence of Water Travel Time and Ocean Effect on Spring/Summer Chinook SAR (predicted) predicted SAR 6% 4% 2% 0% BiOp flow targets Good ocean Average ocean Poor ocean 0 10 20 30 40 Water travel time (days) Snake R. spring/summer chinook
Methods for Travel Time Smolt travel time is defined as the amount of time needed for juvenile migrants to transit the river system between any two points. All estimates made using of PIT tag technology.
Median travel time estimates were calculated for each temporal release block for the Lower Granite to McNary Dam Reach, Rock Island to McNary Dam Reach and McNary to Bonneville Dam Reach.
Methods for Reach Survival Estimates Survival estimated using Cormack- Jolly-Seber tag-recapture methodology. Time series limited by installation of PIT tag facilities (John Day 1998). Longest time series available for Snake River migrants (also has the greatest changes in variables of interest)
Environmental Variables Water Transit Time Flow variable quantified as the summation of water transit times for each reservoir incorporated in a reach. Spill Proportion Daily Spill/Total discharge averaged over a seven day median passage window for each species and project. Water Temperature averages of river temperature developed for 7 day blocks around the median dates of passage.
Yearling Chinook and Steelhead Travel Time versus WTT LGR to McN 1998 to 2005 30 25 20 y = 1.065x + 0.9364 R 2 = 0.5113 15 10 5 0 y = 1.2501x - 1.8495 R 2 = 0.8287 0 5 10 15 20 Water Transit Time CH1_H&W ST_HW Linear (CH1_H&W) Linear (ST_HW)
Yearling Chinook and Steelhead Survival versus WTT LGR to McN 1.0 0.9 y = -0.0236x + 0.9663 R 2 = 0.4196 0.8 0.7 0.6 0.5 0.4 0.3 y = -0.0439x + 1.0065 R 2 = 0.4851 0.2 0 5 10 15 20 Water Transit Time CH1_H&W ST_HW Linear (CH1_H&W) Linear (ST_HW)
Yearling Chinook and Steelhead Survival versus Avg Proportion Spill LGR to McN 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 y = 0.0054x + 0.5368 R 2 = 0.4598 y = 0.0118x + 0.1644 R 2 = 0.6584 0 10 20 30 40 50 60 Avg Spill Proportion (LGS, LMN,IHR,MCN) CH1_H&W ST_HW Linear (CH1_H&W) Linear (ST_HW)
Yearling Chinook and Steelhead Travel Time versus WTT McN to BVL 14 12 10 y = 0.6043x + 3.6429 R 2 = 0.4685 8 6 4 2 0 y = 0.9544x + 1.4913 R 2 = 0.9219 0 5 10 15 Water Transit Time CH1_H&W Linear (CH1_H&W) ST_H&W Linear (ST_H&W)
Subyearling Chinook Travel Time versus WTT Lower Granite Dam to McNary Dam Travel Time (d) LGR to MC 45 40 35 30 25 20 15 10 5 0 0 5 10 15 20 25 30 35 Avg WTT (d) LGR to MCN y=8.77911 + 0.67736X adj R 2 = 0.30, p= 0.00037 Weighted Regression AHW
Subyearling Chinook Survival versus WTT Lower Granite to McNary Dam Survival LGR to MCN 1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 5 10 15 20 25 30 35 Avg WTT (d) LGR to MCN y=0.80298-0.01647x adj R 2 = 0.64, p= 0.00000 Weighted Regression AHW
Subyearling Chinook Survival versus Avg Spill Lower Granite to McNary Dam 1998 to 2006 1 0.9 0.8 y=0.32751 + 0.92651 adj R 2 = 0.58, p = 0.00000 Survival LGR to MCN 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 Avg Spill (Percent) LGS, LMN, IHR, MCN Weighted Regression AHW
1 0.9 Subyearling Chinook Survival versus Avg Temp Lower Granite to McNary Dam y=1.21499-0.03703x adj R 2 = 0.45, p=0.00007 Survival LGR to MCN 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 12 14 16 18 20 22 24 Avg Temp (degree C) LGS, LMN, IHR, MCN Weighted Regression AHW
Juvenile Summary All data collected and analyzed to-date shows flow and spill as the important factors affecting the overall survival of juvenile migrants transiting the hydroelectric power system. Flow and spill affect the migration timing and ocean entry of juvenile salmonids. Small incremental changes in flow volumes are difficult to quantify for fish survival. However, all data collected suggests that decreasing flows increases the risk to the already high risk populations. Given BIOP flow targets stocks are still at risk (average-poor climate/ocean conditions). Any degradation in flows will place stocks at higher risk.
Flow vs Water Transit Time 14 Lower Granite Tailwater to Ice Harbor Dam Water Transit Time (d) 12 10 8 6 4 2 0 BiOp Flow 85-100 Kcfs WTT 7.7-6.6 Days 0 50 100 150 200 250 Average Flow LGS, LMN and IHR (kcfs) McNary to Bonneville Dam 14 Water Transit Time (d) 12 10 8 6 4 2 0 0 50 100 150 200 250 300 350 400 Average Flow BON, TDA, JDA (kcfs) BiOp Flow 220-260 Kcfs WTT 7.6-6.4 Days