South Africa PRIMA Operating Rules. Model Trans-boundary Operating Process PRIMA,TPTC etc Trans-boundary Agreement Operational Committee Representatives

South Africa PRIMA Operating Rules

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.


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.


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%


Determine the operating rule


Review operating rules


Review operating rules

Verifying and checking

Integration

Crocodile

Moz

ambi

que

Kaap

Wit

Compliance Checking

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:


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


Water use



Inflow: 120 m3s-1

Release: 90 m3s-1

Time series graphs


H 0 NoneM 1 80%L 1 75%

Release comparisonRelease Status 1Forecasted Dam TrajectoriesComparative Dam Trajectories


Water use



Inflow: 120 m3s-1

Release: 90 m3s-1

Time series graphs


H 0 NoneM 1 80%L 1 75%

Release comparisonRelease Status 2Forecasted Dam TrajectoriesComparative Dam Trajectories

3 monthaverage

1 monthaverage


Water use



Inflow: 120 m3s-1

Release: 90 m3s-1

Time series graphs


H 0 NoneM 1 80%L 1 75%



Water use



Inflow: 120 m3s-1

Release: 90 m3s-1

Time series graphs


H 0 NoneM 1 80%L 1 75%



Water use



Inflow: 120 m3s-1

Release: 90 m3s-1

Time series graphs


H 0 NoneM 1 80%L 1 75%



Water use

Komatipoort Weir

Flow rateYesterday Today 3 Day Average

1.8 3 2.5


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.


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

Thank you

Documents

South Africa PRIMA Operating Rules. Model Trans-boundary Operating Process PRIMA,TPTC etc Trans-boundary Agreement Operational Committee Representatives