1. Water Budget Modeling: WEAP Kaan Tuncok
Module 3: Environmental Objectives, Programme of Measures, Economic Analysis, Exemptions
Water Budget Modeling: WEAP Kaan Tuncok
Afyon, 2015

2. Outline What is WEAP? Brief overview of WEAP
Examples of issues that can be modeled
When will the new system be ready?
Exercise

3. Water Evaluation And Planning System
Integrated watershed hydrology and water planning
General purpose model building, data management and scenario analysis tools.
Integrated analysis across demand and supply.
Transparent, flexible and user-friendly with low initial data requirements.
Similar user interfaces and terminologies.
Widely used in Governments, Universities, Consulting Companies, Utilities and NGOs: 100s of users worldwide.
Available at no charge to non-profit, academic and governmental institutions based in developing countries.

4. Water Evaluation And Planning System
Integrated watershed hydrology and water planning model
GIS-based, graphical drag & drop interface
Physical simulation of water demands and supplies
Additional simulation modeling: user-created variables, modeling equations and links to spreadsheets, scripts & other models
Scenario management capabilities
Groundwater, water quality, reservoir, hydropower and financial modules

5. WEAP Network Schematic
Linking supply and demand
Return flows to surface or ground water or treatment plants
5 Main Views

6. Data for the demand sites is displayed numerically and graphically
Data View
Data for the demand sites is displayed numerically and graphically .

7. Read in timeseries data from text files or Access database
Reading from Files
Read in timeseries data from text files or Access database

8. Results can be displayed in a number of formats and scales
Results View
Results can be displayed in a number of formats and scales

9. Results Displayed on the Map

10. Favorite charts can be selected to give quick overviews
Scenario Explorer
Favorite charts can be selected to give quick overviews

11. Hydropower
Specify capacities, efficiencies, and other properties of power generation

12. Specify variable and fixed costs and revenues
Financial Analysis
Specify variable and fixed costs and revenues

13. Specify pollutant loadings
Water Quality
Specify pollutant loadings

14. Linking WEAP to MODFLOW

15. Linking WEAP to MODFLOW

16. Examples of WEAP Analyses
Sectoral demand analyses
Land use & climate change impacts on hydrology
Water conservation
Water rights and allocation priorities
Groundwater and streamflow simulations
Reservoir operations
Hydropower generation
Financial analysis
Pollution tracking
Ecosystem requirements

17. Linking WEAP to Other Software
Customized/Programmed links
Groundwater flow and particle tracking models
MODFLOW, MODPATH
Surface water quality model
Qual2K
Semi-automated calibration
PEST
Call WEAP using application programming interface (API)
Scenario analysis
CARS (RAND Corporation)
Model calibration
Sensitivity analysis, complex model building
Scripts: Visual Basic, Javascript, Python, Perl

18. WEAP Applications Water Systems Planning Transboundary Water Policy
Small Reservoirs Project, Ghana/Brazil
California Water Plan, California, USA
Guadiana River, Spain
Transboundary Water Policy
Okavango River, Angola/Namibia/Botswana
Lower Rio Grande, USA/Mexico
Mekong River, Thailand/Cambodia/Vietnam/Laos
Jordan River, Syria/Israel/Jordan
Climate Change Studies
Sacramento and San Joaquin River Basins, California, USA
Massachusetts Water Resources Authority, Massachusetts, USA
Yemen Second National Communication
Mali Second National Communication
Ecological Flows
Connecticut Department of Environmental Protection
Town of Scituate, Massachusetts, USA
Water Utility DSS Application
Case studies in Portland, Oregon; Austin, Texas; and Philadelphia, Pennsylvania.

19. Linking Water Decision Processes
Groundwater depletion
Water quality
Unmet ecological flows
Costs
Limited sectoral water, increased energy requirements for pumping.
Increased energy requirements for desalination.
Insufficient water for sectors, even with increased groundwater pumping.
Still insufficient water--further enhance supply with desalination.
Water demand in each sector
Efficiency and Sustainability
Water
Demand
DSS
Water Supply
Storage
Sectoral policies
Less water-intensive processes and technologies
Water requirements for sectors
Water conservation
Water requirements
Reduced water demands

20. Exercise

21. How much river water can a user use?
River flow ≠ Water available to a user
Also reach gains/losses, reservoir storage, consumptive use, return flows, groundwater, soil moisture,
Delivery targets and water allocation priorities
Appropriation doctrine (first in time, first in right)
By purpose (e.g.: urban demands before environmental)
By location (e.g.: upstream, then downstream, or reverse)
Prior withdrawals and deliveries
Changes from month to month and year to year

22. Draw a System Schematic
Identify major system components and linkages
Water sources (surface and groundwater)
Demand sites (agricultural, urban, etc..)
Source connections to demand sites
Outflows from demand sites after use
Example 1: A river can supply water to an upstream city and downstream agricultural district. 40% of the city’s withdrawals are collected, treated, returned to the river, and available for downstream use by the agricultural district.

23. Calculate Allocations
Step 1: Draw the schematic
Step 2: Determine delivery targets for demand sites (demands)
Step 3: Assign priorities to demand sites (delivery preferences)
Step 4: Determine water availability
Sources
Return flows
Step 5: Allocate remaining available water to meet delivery target of highest priority demand site
Repeat Steps 4 and 5 for next highest priority site.

24. Calculate Allocations (cont.)
Example 2: A river can supply an upstream city and downstream agricultural district. 40% of the city’s withdrawals are collected, treated, discharged, and available for downstream use by the agricultural district.
70 hm3 is available in the river this year. The table shows demand site priorities and delivery targets.
What water volume is allocated to each demand site?
Demand Site
Priority [rank]
Delivery Target [hm3/yr]
City
2 (lower) 30
Agricultural
1 (high) 60

25. Calculate Allocations (cont.)
Always use mass balance to determine water available to a user (or at model node)
Data requirements and allocation calculations get more complex as add demand sites and return flows
Hydroinformatics and computer modeling can help!

26. WEAP Allocation Math
In each time step, WEAP solves a small linear program
Maximize Demand Satisfaction
Meet supply priorities
Obey demand site preferences
Mass balance
Other constraints
Embed the LP in a time-series simulation (psuedo code)
Such that:

27. Using WEAP
Major Modules
Schematic
Data
Results
Scenario Explorer

28. WEAP Schematic Drag and drop system node components Demand sites
Reservoirs, etc.
Drag, click, and drop system link components
Rivers
Transmission links
Return flows
Add GIS layers to help place components
Must include all infrastructure you plan to test in Scenario Explorer

29. Weaping River Example Schematic

30. WEAP Data Module Enter data for each schematic component
Rivers: Headflows for each month of the simulation
Reaches: Reach gains for each month of the simulation
Diversions: Minimum flow requirements as reach losses
Demand sites: activity levels, use rates, losses, consumption, demand priority (1=highest; 99=lowest)
Transmission links: Max flows, supply preference
Return flows: routing (percent returned)
Reservoirs: storage capacity, initial storage, volume-elevation curve, evaporation, pool definitions, buffer coefficients, priority
Enter data or read from input file

31. Alternatively, right-click any schematic component to also get to the Data module

32. Tree view, Buttons, and Tabs to navigate to desired data

33. WEAP Results Module
Click the Results icon and recalculate (all scenarios)
Choose results from schematic or dropdown lists
Numerous options to view, tabulate, and export

34. Water demands by Demand Site

35. WEAP Scenario Explorer
Define and manage scenarios from Data module
Enter input data here too

36. WEAP Scenario Explorer (cont.)
Use Scenario Explorer icon to open scenario dashboard

37. Conclusions WEAP can simulate priority-based water allocations
Drag and drop interface to draw system schematic
Entered head flow data for one river
View results in numerous formats