CE QUAL W2 Model Applications to Examine the Effects of Operations on Fish Habitat in Lake Murray Meeting to Report on Preliminary Results Andy Sawyer and Jim Ruane, REMI May 22, 2007
Relicensing Issues Identified by the Water Quality Technical Working Committee The causes of striped bass fish kills reported in previous years, especially factors related to Saluda Hydro operations The effects of Unit 5 operations on entrainment of blue back herring Determination of operational changes that might increase habitat for striped bass and blue back herring Track any impacts that could occur to the tailwater cold water fishery due to potential operational changes
Factors Considered in Addressing Relicensing Issues Annual flow regimes Pool level management Unit 5 operations In lake and release water quality Habitat for striped bass and blue back herring Water quality, meteorological, and operations data over the period 1990 2005 Emphasis will be placed on section of reservoir from Blacks Bridge to Saluda Dam
Plan for Using CE QUAL W2 to Address the Water Quality TWC Relicensing Issues 1. Analyze water quality, meteorological, flow, and operations data for the period of study 2. Set up CE QUAL W2 for the years when major striped bass fish kills occurred as well as other years 3. Run models to identify the causes that apparently contributed to the fish kills 4. Use the models to explore ways to avoid such fish kills in the future, with emphasis on project operations
Preliminary Findings High flow, especially during March August, is the primary cause for fish kills Higher flows cause the bottom of the lake to warm which in turn increases the rate of DO depletion Meteorological conditions can affect striper habitat Model results indicate that the temperature and DO range of tolerable striper habitat in Lake Murray is approximately: T< 27 o C and DO> 2.5 mg/l Preferential use of Unit 5 helps preserve colder bottom water and was predicted to improve DO and increase striper habitat
Lake Murray Surface Elevation 1990 2005 Years with documented striped bass kills are red
Lake Murray Surface Elevation 1990 2005 Typical Years Only (no special drawdowns) Years with documented striped bass kills are red
Average Annual Flow Saluda River at Chappells
Excel Table with Monthly Average Flow Below Saluda
Flow Frequency Saluda River Below Lake Murray Flow Frequency Based on Daily Average Flow in Saluda Tailrace, March June Only Daily Average Flow (cfs) 20000 18000 16000 14000 12000 10000 8000 6000 4000 2000 0 0 10 20 30 40 50 60 70 80 90 100 % Exceedence 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2005
Cumulative Outflow March December Years with documented striped bass kills are red
Forebay Temperature Profiles
Forebay Temperature Profiles
Forebay Temperature Profiles
Forebay Temperature Profiles
Forebay DO Profiles
Forebay DO Profiles
Forebay DO Profiles
Forebay DO Profiles
Lake Murray Contour Plots June 2002 Temperature June 2005 Temperature 105 105 100 100 95 95 90 90 85 85 80 80 75 70 65 60 55 0 5 10 15 20 25 30 35 75 70 65 60 55 0 5 10 15 20 25 30 35 June 2002 DO June 2005 DO 105 100 95 90 85 80 75 70 65 60 55 0 5 10 15 20 25 30 35 105 100 95 90 85 80 75 70 65 60 55 0 5 10 15 20 25 30 35
Lake Murray Contour Plots July 2002 Temperature July 2005 Temperature 105 105 100 100 95 95 90 90 85 85 80 80 75 75 70 70 65 65 60 60 55 0 5 10 15 20 25 30 35 55 0 5 10 15 20 25 30 35 July 2002 DO July 2005 DO 105 105 100 100 95 95 90 90 85 85 80 80 75 70 65 60 55 0 5 10 15 20 25 30 35 75 70 65 60 55 0 5 10 15 20 25 30 35
Lake Murray Contour Plots August 2002 Temperature August 2005 Temperature 105 105 100 100 95 95 90 90 85 85 80 80 75 75 70 70 65 65 60 60 55 0 5 10 15 20 25 30 35 August 2002 DO 55 0 5 10 15 20 25 30 35 August 2005 DO 105 105 100 100 95 95 90 90 85 85 80 80 75 75 70 70 65 65 60 60 55 0 5 10 15 20 25 30 35 55 0 5 10 15 20 25 30 35
Lake Murray Contour Plots September 2002 Temperature September 2005 Temperature 105 105 100 100 95 95 90 90 85 85 80 80 75 75 70 70 65 65 60 60 55 0 5 10 15 20 25 30 35 September 2002 DO 55 0 5 10 15 20 25 30 35 September 2005 DO 105 105 100 100 95 95 90 90 85 85 80 80 75 75 70 70 65 65 60 60 55 0 5 10 15 20 25 30 35 55 0 5 10 15 20 25 30 35
Model Calibration Model was originally calibrated to 3 years: 1992, 1996 and 1997 Model SOD was adjusted in each of the 3 years to improve DO calibration
1996 Lake Murray Temperature Profiles Forebay Model vs. Data
1996 Lake Murray Temperature Profiles 19 Kilometers Upstream of Dam Model vs. Data
1996 Lake Murray DO Profiles Forebay Model vs. Data
1996 Lake Murray DO Profiles 19 Kilometers Upstream of Dam Model vs. Data
Release Temperature Model vs. Data 1996 Model Prediction vs Observed Discharge Temperature 25 23 21 Model Hourly Observed Temperature C o 19 17 15 13 11 9 7 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/1 1996 Date
Release DO Model vs. Data Dissolved Oxygen (mg/l) 14 13 12 11 10 9 8 7 6 5 4 3 2 1 1996 Model Prediction and Observed Discharge DO 0 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/1 1996 Date Model Hourly Observed
Temperature in Front of Unit 5 Model vs. Data 1996 Model Prediction vs Observed Temperature in front of Unit 5 25 Temperature C o 23 21 19 17 15 13 Model Observed with Profile 11 9 7 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/1 1996 Date
DO in Front of Unit 5 Model vs. Data 1996 Model Prediction vs Observed Temperature in front of Unit 5 Temperature C o 12 11 10 9 8 7 6 5 4 3 2 1 Model Observed with Profile 0 1/1 2/1 3/1 4/1 5/1 6/1 7/1 8/1 9/1 10/1 11/1 12/1 1996 Date
Striped Bass Habitat in Lake Murray Zone Volume, T<27 and DO>2.5 2000 1800 1600 Volume Mm3 1400 1200 1000 800 600 400 200 1991 1992 1996 1997 1998 2005 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3
DO Animation with Striped Bass Habitat Highlighted
Sensitivity to Operations Original outflow assumption for all modeled years: Units 1, 2 and 4 Q < 9,600 cfs Unit 5 9,600 < Q < 15,600 cfs Unit 3 Q > 15,600 cfs When Unit 5 is operated first (Q < 6,000 cfs), cooler bottom water is conserved and availability of striper habitat improves
Evaluation of Raised Pool Levels Scenarios Considered: 354(Jan1) to 358(May1 Sept1) to 354(Dec 31) 350(Jan1) to 358(May1 Sept1) to 350(Dec 31) Assumptions: Assumed 500 cfs for minimum release Assumed reserve generation averaged 3hr every two weeks at 18,000 cfs Balance of releases were assumed to be used to supplement system demand Approach: The above scenarios were developed by KA using daily average flows using HEC ResSim CE QUAL W2 was run using daily average flows and release flows were adjusted so that target pool levels were attained Using the daily average flows that were adjusted using the CE QUAL W2 model the hourly flows for each day were developed using the assumptions above
Comparison of Original Flow Assumption and Alternative Unit 5 Operation Scenarios Volume Mm3 1991 Zone Volume, T<27 and DO>2.5 2000 1800 Original Q Assumption 1600 Orig Q Assumption Unit 5 on first 1400 Orig Q Assumption Unit 5 on last 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3 Volume Mm3 1996 Zone Volume, T<27 and DO>2.5 2000 1800 Original Q Assumption 1600 Orig Q Assumption Unit 5 on first 1400 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3 Volume Mm3 1998 Zone Volume, T<27 and DO>2.5 2000 1800 Original Q Assumption 1600 Orig Q Assumption Unit 5 on first 1400 Orig Q Assumption Unit 5 on last 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3 Volume Mm3 2005 Zone Volume, T<27 and DO>2.5 2000 1800 1600 Original Q Assumption 1400 Orig Q Assumption Unit 5 on first 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3
1998 Animation Comparison of Original Flow Assumption and Unit 5 on First Scenario
Tailrace Temperature Comparison of Original Flow Assumption and Unit 5 on First Scenario Temperature o C 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 1991 Release Temperature Current Unit 5 on First 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27 Temperature o C 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 Current Unit 5 on First 1996 Release Temperature 1/1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Temperature o C 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 1998 Release Temperature Current Unit 5 on First 1/1 2/1 3/5 4/5 5/7 6/7 7/9 8/9 9/10 10/11 11/12 12/13 Temperature o C 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 2005 Release Temperature Current Unit 5 on First 1/1 2/1 3/5 4/5 5/7 6/7 7/9 8/9 9/10 10/11 11/12 12/13
Tailrace DO Comparison of Original Flow Assumption and Unit 5 on First Scenario Dissolved Oxygen (mg/l) 1991 Release DO 12 11 10 9 8 7 6 5 Current 4 Unit 5 on First 3 2 1 0 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27 Dissolved Oxygen (mg/l) 1996 Release DO 12 11 10 9 8 7 6 5 Current 4 3 Unit 5 on First 2 1 0 1/1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Dissolved Oxygen (mg/l) 1998 Release DO 12 11 10 9 8 7 6 5 4 Current 3 2 Unit 5 on First 1 0 1/1 2/1 3/5 4/5 5/7 6/7 7/9 8/9 9/10 10/11 11/12 12/13 Dissolved Oxygen (mg/l) 2005 Release DO 12 11 10 9 8 7 6 5 4 Current 3 2 Unit 5 on First 1 0 1/1 2/1 3/5 4/5 5/7 6/7 7/9 8/9 9/10 10/11 11/12 12/13
Forebay Temperature Profiles Comparison of Original Flow Assumption and Unit 5 on First Scenario
Temperature at the Intake to Unit 5 Comparison of Original Flow Assumption and Unit 5 on First Scenario Temperature o C 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 1991 Temperature in front of Unit 5 Current Unit 5 on First 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27 Temperature o C 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 Current 1996 Temperature in front of Unit 5 Unit 5 on First 1/1 1/31 3/1 3/31 4/30 5/30 6/29 7/29 8/28 9/27 10/27 11/26 12/26 Temperature o C 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 1998 Temperature in front of Unit 5 Current Unit 5 on First 1/1 1/31 3/3 4/2 5/3 6/2 7/3 8/2 9/2 10/2 11/2 12/2 Temperature o C 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 2005 Temperature in front of Unit 5 Current Unit 5 on First 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27
DO at the Intake to Unit 5 Comparison of Original Flow Assumption and Unit 5 on First Scenario Dissolved Oxygen (mg/l) 1991 DO in front of Unit 5 12 11 10 9 8 7 6 5 4 Current 3 Unit 5 on First 2 1 0 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27 Dissolved Oxygen (mg/l) 1996 DO in front of Unit 5 12 11 10 9 8 7 6 5 Current 4 3 Unit 5 on First 2 1 0 1/1 1/31 3/1 3/31 4/30 5/30 6/29 7/29 8/28 9/27 10/27 11/26 12/26 Dissolved Oxygen (mg/l) 1998 DO in front of Unit 5 12 11 10 9 8 7 6 5 4 3 Current 2 Unit 5 on First 1 0 1/1 1/31 3/3 4/2 5/3 6/2 7/3 8/2 9/2 10/2 11/2 12/2 Dissolved Oxygen (mg/l) 2005 DO in front of Unit 5 12 11 10 9 8 7 6 5 4 3 Current 2 Unit 5 on First 1 0 1/1 1/31 3/2 4/1 5/1 5/31 6/30 7/30 8/29 9/28 10/28 11/27 12/27
1991 Pool Level Management Elevation (ft) 1991 Surface Elevation 360 359 358 357 356 355 354 353 Actual 352 Elevation 354 Scenario 351 350 Elevation 350 Scenario 349 348 1/1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Date 1991 Zone Volume, T<27 and DO>2.5 Volume Mm3 2000 1800 Original Q Assumption 1600 Elev 354 Scenario 1400 Elev 350 Scenario 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3
1996 Pool Level Management Elevation (ft) 1996 Surface Elevation 360 359 358 357 356 355 354 353 Actual 352 Elevation 354 Scenario 351 350 349 1/1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Date 1996 Zone Volume, T<27 and DO>2.5 2000 1800 Original Q Assumption Volume Mm3 1600 Elev 354 Scenario 1400 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3
1998 Pool Level Management Elevation (ft) 1998 Surface Elevation 360 359 358 357 356 355 354 Actual 353 352 Elevation 354 Scenario 351 Elevation 350 Scenario 350 349 1/1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Date 1998 Zone Volume, T<27 and DO>2.5 Volume Mm3 2000 1800 Original Q Assumption 1600 Elev 354 Scenario 1400 Elev 350 Scenario 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3
2005 Pool Level Management Elevation (ft) 2005 Surface Elevation 360 359 358 357 356 355 354 353 Actual 352 Elevation 354 Scenario 351 Elevation 350 Scenario 350 349 1/1 2/1 3/4 4/4 5/6 6/6 7/8 8/8 9/9 10/10 11/11 12/12 Date 2005 Zone Volume, T<27 and DO>2.5 2000 1800 1600 Original Q Assumption Elev 354 Scenario Volume Mm3 1400 Elev 350 Scenario 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3
Excel Plots
Temperature and DO at the Intake to Unit 5 with Pool Level Management Temperature o C 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 Current 1996 Temperature in front of Unit 5 Elevation 354 Scenario 1/1 1/31 3/1 3/31 4/30 5/30 6/29 7/29 8/28 9/27 10/27 11/26 12/26 Temperature o C 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 1998 Temperature in front of Unit 5 Current Elevation 354 Scenario 1/1 1/31 3/3 4/2 5/3 6/2 7/3 8/2 9/2 10/2 11/2 12/2 Dissolved Oxygen (mg/l) 1996 DO in front of Unit 5 12 11 10 9 8 7 6 5 Current 4 3 Elevation 354 Scenario 2 1 0 1/1 1/31 3/1 3/31 4/30 5/30 6/29 7/29 8/28 9/27 10/27 11/26 12/26 Dissolved Oxygen (mg/l) 1998 DO in front of Unit 5 12 11 10 9 8 7 6 5 4 Current 3 2 Elevation 354 Scenario 1 0 1/1 1/31 3/3 4/2 5/3 6/2 7/3 8/2 9/2 10/2 11/2 12/2
Comparison of Current Phosphorus Load and Reduced Phosphorus Scenario 1998 Zone Volume, T<27 and DO>2.5 Volume Mm3 2000 1800 Current Phosphorus Load 1600 1400 Reduced TP and SOD 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3 2005 Zone Volume, T<27 and DO>2.5 Volume Mm3 2000 1800 Current Phosphorus Load 1600 Reduced TP and SOD 1400 1200 1000 800 600 400 200 0 5/1 6/1 7/2 8/2 9/2 10/3 11/3
Preliminary Conclusions Nutrients are the single dominant factor that can enhance striped bass habitat Flow is a dominant factor, but cannot be controlled to avoid fish kills Met conditions can be a periodic factor that alleviates otherwise dominant factors like flow Striped bass habitat conditions can be improved in some years by maintaining high summer pool levels (~ elev. 358 ft) Unit 5 preferential operations can improve striped bass habitat in some years
Next Steps 1. For selected years, finalize assessment (i.e., assess changes in releases) of operating guide for U5 preference for first on, last off operation using the hourly releases 2. For selected years, finalize assessment of maintaining summer pool levels at 358 3. For selected years, finalize assessment of the combination of maintaining summer pool levels at 358 with U5 preference for first on, last off operation using the hourly releases 4. Analyze additional years, especially a low flow year 5. Assess effects of minimum winter pool level, including effects on Little Saluda embayment, increased SOD, internal nutrient cycling, aquatic plants, sedimentation in coves,