Model
Trans-boundary Operating ProcessPRIMA ,TPTC etc
Trans-boundary Agreement
Operational CommitteeRepresentatives for water management institutions
(WUA, CMA etc)
Define integrated operating objectives
ModelDetermine operating rule
Current catchment conditions
Determine operations for next season(Restrictions)
LocalWater
Management Authority
Compliance checkPRIMA
OperationsTask Team/Data
Unit
System interactionsMIS
DSS Operator
Mike Basin
Water use
Dam Levels
Operating Rules
Super user-Access and change everything
Operator-Access limited through GUI
Viewer-Access limited cannot change system information
Operating Rules Process
Define operating objective-Per catchment resource-Integrated operating objective (international and ecological requirements)
Determine operating rule-Per catchment/dam-Integrated operating rule
Review operating rule-Determine critical period-Test medium term operations
- Stochastic runs- Dam trajectories- Check assurance of supply
Short term/Compliance-Compliance-Operating rule
-Dam levels-Releases-Restrictions
-Water use (Water balance)-Flows (Environmental requirement)
Example Developing and Operating Rule
Define the operating objectives
1. Use water from run of river first then if this is not sufficient release water from Kwena Dam
2. Normal: 1. Dam level should be back above 90% the next May. An increase in dam level of
more than 40% can be expected from November to May.2. Dam level should preferably not go down below 60% but be kept above 50% as far
as possible.3. Restrictions should normally be implemented from May to October/November.
Conservative approach in winter months4. Wet season turning about November/December dam fills. Generally keep dam
level to 60% at 15 December.
Example Developing and Operating Rule
Define the operating objectives
1. Drought:1. Dam level should at least be back at 70% if the previous year was a drought year.
Increase in dam level of 30% to 35% could be expected if it is a dry year again.2. Dam level should not go down below 35% but preferably be kept above 40% under
these conditions.3. If it is the third or fourth year of a drought and still a dry year ahead under these
conditions it is possible to go down to below 20% but not lower than 15% depending on the time of the year and the forecast.
4. In a drought we assume the turning point to be much later and we work on the end of January.
Example Developing and Operating Rule
Determine the operating rule
Normal condition•Choose representative hydrological sequence (50th percentile)•Choose a dam level and iteratively restrict users in so that we reach a level of 90% at May the next year•Change the dam level and repeat the process•Create a curve showing restriction level versus dam level for normal condition
Drought condition•Choose representative hydrological sequence (25th percentile)•Choose a dam level and iteratively restrict users in so that we reach a level of 70% at May the next year•Change the dam level and repeat the process•Create a curve showing restriction level versus dam level for normal condition
Two curves generated for drought and normal condition
Development of operating rules
Dam Level(%) Restriction Level Percentage of allocation90 24% 76%80 33% 67%70 46% 54%60 57% 43%50 66% 34%40 76% 24%30 95% 5%20 100% 0%10 100% 0%
System Overview
• Purpose: Give good general overview of system allowing manager to identify problems quickly
• Critical information presented on– Dams– Flows – Water Use– Missing information
Prima OperationsHomeDamsFlows
Water use
System Overview (Double click on elements for more information)
Flow: Meets IIMA Not compliant
Water use: 0-25% 25%-50% 50%-75% 75%-100% >100%
Dam Level:
Prima OperationsHomeDamsFlows
Water use
All Dams Pongolapoort DamVolume: 1 200 000 m3
Percentage full: 70%Storage capacity: 780 000 m3
Inflow: 120 m3s-1
Release: 90 m3s-1
Time series graphs
Curtailment levelsAssurance Level Restriction
H 0 NoneM 1 80%L 1 75%
Release comparisonRelease StatusForecasted Dam TrajectoriesComparative Dam Trajectories
Prima OperationsHomeDamsFlows
Water use
All Dams Pongolapoort DamVolume: 1 200 000 m3
Percentage full: 70%Storage capacity: 780 000 m3
Inflow: 120 m3s-1
Release: 90 m3s-1
Time series graphs
Curtailment levelsAssurance Level Restriction
H 0 NoneM 1 80%L 1 75%
Release comparisonRelease Status 1Forecasted Dam TrajectoriesComparative Dam Trajectories
Prima OperationsHomeDamsFlows
Water use
All Dams Pongolapoort DamVolume: 1 200 000 m3
Percentage full: 70%Storage capacity: 780 000 m3
Inflow: 120 m3s-1
Release: 90 m3s-1
Time series graphs
Curtailment levelsAssurance Level Restriction
H 0 NoneM 1 80%L 1 75%
Release comparisonRelease Status 2Forecasted Dam TrajectoriesComparative Dam Trajectories
3 monthaverage
1 monthaverage
Prima OperationsHomeDamsFlows
Water use
All Dams Pongolapoort DamVolume: 1 200 000 m3
Percentage full: 70%Storage capacity: 780 000 m3
Inflow: 120 m3s-1
Release: 90 m3s-1
Time series graphs
Curtailment levelsAssurance Level Restriction
H 0 NoneM 1 80%L 1 75%
Release comparisonRelease StatusForecasted Dam TrajectoriesComparative Dam Trajectories
Prima OperationsHomeDamsFlows
Water use
All Dams Pongolapoort DamVolume: 1 200 000 m3
Percentage full: 70%Storage capacity: 780 000 m3
Inflow: 120 m3s-1
Release: 90 m3s-1
Time series graphs
Curtailment levelsAssurance Level Restriction
H 0 NoneM 1 80%L 1 75%
Release comparisonRelease StatusForecasted Dam TrajectoriesComparative Dam Trajectories
Prima OperationsHomeDamsFlows
Water use
All Dams Pongolapoort DamVolume: 1 200 000 m3
Percentage full: 70%Storage capacity: 780 000 m3
Inflow: 120 m3s-1
Release: 90 m3s-1
Time series graphs
Curtailment levelsAssurance Level Restriction
H 0 NoneM 1 80%L 1 75%
Release comparisonRelease StatusForecasted Dam TrajectoriesComparative Dam Trajectories
Prima OperationsHomeDamsFlows
Water use
Komatipoort Weir
Flow rateYesterday Today 3 Day Average
1.8 3 2.5
Prima OperationsHomeDamsFlows
Water use
Water use information can be incorporated into the system
However
Existing water use data is not reliable and methodology for the collection of this information is not well established.
Many areas no water meters are available and assessments based on remote sensing information tend to be inaccurate.
Prima OperationsHomeDamsFlows
Water use
Idea for identification of water use
Run a water balance
Loss/Gain = Upstream gauge + Tributaries (n) – Downstream gauge – estimated evaporation – Estimated seepage
Loss/gain vs Allocation