Investigation of Complex River SystemOperational Policy –

Modeling Obstacles and Solutions

James VanShaarRiverside Technology, inc.

(TVA Flood Control Operations EIS Model)

Purpose To determine if changes in reservoir system operating

policies could create greater overall public value

RESERVOIR OPERATIONS STUDYBackground

RESERVOIR OPERATIONS STUDYBackground

Purpose To determine if changes in reservoir system operating

policies could create greater overall public value

System Integrated system provides multiple benefits Trade-offs create competing demands for use of water Stakeholders have different views on priorities

RESERVOIR OPERATIONS STUDYBackground

NO HoldsBarred!

Purpose To determine if changes in reservoir system operating

policies could create greater overall public value

System Integrated system provides multiple benefits Trade-offs create competing demands for use of water Stakeholders have different views on priorities

Plan Two-year Reservoir Operations Study initiated Any and all uses of the water that flows through the

reservoir system and all aspects of the current operating policies

RESERVOIR OPERATIONS STUDYBackground

Issues Flood risk Water quality Economic Environmental Cultural Navigation Water supply Recreation (reservoir and downstream) Hydropower and non-hydropower generation Public values on the use of water Support of other federal agencies

Base Case Simulation 99 years at 6 hour timestep: ~144k timesteps

RESERVOIR OPERATIONS STUDYBackground

Base Case Simulation 99 years at 6 hour timestep: ~144k timesteps

RESERVOIR OPERATIONS STUDYBackground

Base Case Simulation 99 years at 6 hour timestep: ~144k timesteps 36 dams and 14 damage centers

RESERVOIR OPERATIONS STUDYBackground

Base Case Simulation 99 years at 6 hour timestep: ~144k timesteps 36 dams and 14 damage centers 69 historic storms scaled 1.5x, 2.0x and 2.5x

RESERVOIR OPERATIONS STUDYBackground

Lather. Rinse. . .

Base Case Simulation 99 years at 6 hour timestep: ~144k timesteps 36 dams and 14 damage centers 69 historic storms scaled 1.5x, 2.0x and 2.5x

RESERVOIR OPERATIONS STUDYBackground

Base Case Simulation 99 years at 6 hour timestep: ~144k timesteps 36 dams and 14 damage centers 69 historic storms scaled 1.5x, 2.0x and 2.5x

Alternative Scenarios Modify for alternative operational policy Repeat for 5+ alternative operational policies.

RESERVOIR OPERATIONS STUDYBackground

Base Case Simulation 99 years at 6 hour timestep: ~144k timesteps 36 dams and 14 damage centers 69 historic storms scaled 1.5x, 2.0x and 2.5x

Alternative Scenarios Modify for alternative operational policy Repeat for 5+ alternative operational policies.

RESERVOIR OPERATIONS STUDYBackground

Base Case Simulation 99 years at 6 hour timestep: ~144k timesteps 36 dams and 14 damage centers 69 historic storms scaled 1.5x, 2.0x and 2.5x

Alternative Scenarios Modify for alternative operational policy Repeat for 5+ alternative operational policies.

Analysis Extract seasonal and annual peak flow / pool / stage Compare Alternatives against Base Case If necessary, combine / revise alternatives. Repeat.

RESERVOIR OPERATIONS STUDYBackground

Model DesignMajor Concerns

Run-time

Model size

Accuracy of policy representation

Decision tracking: debugging, calibration, reproduction

Extensibility to alternatives

Model DesignPower production rule set

Generic Tributary Algorithms

Applied to virtually all non-sloped power reservoirs

Foundation of all operation policy

Quarantined deviation code for non-conformist projects

Model DesignPower production rule set

Mainstem Fixed Rule (sloped-power reservoir)

Acceptable discharge vs. pool elevation operational points

Watts Bar Fixed Rule

735

737

739

741

743

745

747

0 50 100 150 200 250 300

Watts Bar Discharge (1000 cfs)

Hea

dw

ater

Ele

vati

on

(ft

)

Spillway capacity at elevation 747 is 617,000 cfs

Scaling Range

Surcharge Region

Max LookAhead Elevation

Floating Range

Model DesignPower production rule set

Mainstem Fixed Rule (sloped-power reservoir)

Acceptable discharge vs. pool elevation operational points

Recovery mode

Fixed rule curve abandonment

Model DesignPower production rule set

Model DesignPower production rule set

Results of rule set design

Carefully tested, compact, reused code base

Eliminated re-firing of rules

Decision variables stored

Limited re-solution of objects

Individual policy relegated to parameters, not logic

Model Application System Segmentation

Space

Non-Power Tributary

Model Application System Segmentation

Upper Tributary

Upper Mainstem

Lower Mainstem

Model Application System Segmentation

Space

– Four Models

– Reuse of power rule set

Time

Model ApplicationControl and Data Management

Model ApplicationControl and Data Management

Model ApplicationControl and Data Management

Model ApplicationControl and Data Management

Control Algorithm: For each successive run period--

Modify TSTool and RiverWare batch control files

Run TSTool initialization commands– Access archived data– Locate RiverWare input in expected directory

Run RiverWare using its control file– Import data– Simulation– Export data– Save model with new name

Run TSTool archival commands

– Store results in archive time series files

Model ApplicationControl and Data Management

Design Storms

Apply revised control algorithm for each storm

Revision includes consideration for– Appropriate initial data– Storage location of new archival data

Model ApplicationResults of Approach

Flexibility

– Debugging

– Event isolation

Run-time

Consistency throughout alternatives

Built-in archival of runs / models / decisions

Elimination of model size concerns

Percent Exceedance

Alternative X

Regulated

Alternative Scenarios Alternative Operational Scenario Flood Frequency and Damage Curves

Dollars of Damage

Conclusion

Thank you for your time and attention.

Any Questions?

Fall Creek Falls, TN

Thank you.