Hydrological modeling

Community Water Model

Name of presenter

Towards Innovative Solutions through

Integrative Water Futures Analysis

Peter Burek

EAC Workshop, Entebbe, 4 Dec 2017

Increasing Demands, Increasing Challenges

Domestic water

withdrawals in

Africa increase by

400%

Agricultural water

requirements in

Africa increase by

240% due to

irrigated land

expansion and

climate change

Industrial water

withdrawals in

Africa increase by

350%

Food Domestic Energy & Industry Ecology

Human needs Ecological Health

Lost of wetlands

and biodiversity

River do not reach

the sea

Concept of

environmental flow

By 2050, SSP2 – Middle of the Road scenario

Lake Victoria basin

From 46 Mio. people in 2010 to

87 – 120 Mio. people in 2050(depending on scenario SSP1-SSP3)

90% - 260% increase

Socio-economic change - Population

Socio-economic change - GDP

0

1000

2000

3000

4000

5000

6000

7000

8000

2010 2020 2030 2040 2050

GD

P p

er c

apit

a [U

S$/y

ear/

cap

]

Lake Victoria basin

GDP(PPP) - Middle of the Road

Lake Victoria basin

From 1275 US$/year/cap in 2010 to

6900 US$/year/cap in 2050

550% more GDP per cap. 2050

Middle of the Road scenario (SSP2)

Cultivate land will increase by 20-40% till 2050 for EAC

30000

34000

38000

42000

46000

50000

2010 2020 2030 2040 2050

Cu

ltiv

ated

lan

d [

10

00

ha]

Cultivated Land

EAC SSP1 EAC SSP2 EAC SSP3

Maps available:

www.gaez.iiasa.ac.at

Evolution of cultivated land - EAC

Irrigated land will increase by 60-200% till 2050 for EAC

Maps available:

www.gaez.iiasa.ac.at

Evolution of irrigated land - EAC

0

100

200

300

400

500

600

700

2010 2020 2030 2040 2050

Irri

gate

dl l

and

[1

00

0 h

a]

Irrigated land

EAC SSP1 EAC SSP2 EAC SSP3

Evolution of energy demand and supply

Numbers hydropower

National Water Resources Assessment,

Uganda

Modeling support

to test options and pathways

in order to reach “The Visions”

Modeling approach

Reducing risks of water stress

Water-stress wedge strategies:

efficiency; recycling; reservoir expansion, desalination, etc.

What strategy is best to implement where and when? How much will it cost?

How will this impact land and energy use?

To demonstrate the impact of strategic solution pathways towards more sustainable water use to policy makers.

Hydro-economic modeling framework

Key features represented in the

model:

Drivers: Demand growth;

Resource availability; Climate

change; etc.

Processes: Reservoir

management; Irrigation use;

Electricity generation; Water

pumping; End-use efficiency;

Wastewater treatment; etc.

Impacts: Prices; Demands;

Emissions; Water quality;

Environmental flow; Groundwater

depletion; Resource security; etc.

Decisions: Extract resources;

Operate infrastructure; Expand

infrastructure; Trade resources

Hydrological modelCWATM

Community Water Model

Feature Description

Community driven Open-source but lead by IIASA

Well documented Documentation(Wiki), automatic source code documentation

Easy handling Use of a setting file with all necessary information for the user

Multi-platform Windows, Mac, Linux, Unix - to be used on different platforms (PC,

clusters, super-computers)

Modular Processes in subprograms, easy to adapt to the requirements of options/

solutions

Open source on Github

https://github.com/CWatM

Community Model on the web

https://cwatm.github.io/

Community Water Model

Feature Description

Flexible different resolution, different processes for different needs, links to other

models, across sectors and across scales

Adjustable to be tailored to the needs at IIASA i.e. collaboration with other

programs/models, including solutions and option as part of the model

Multi-disciplinary including economics, environmental needs, social science perspectives etc.

Sensitive Sensitive to the option / solution

Fast Global to regional modeling – a mixture between conceptional and physical

modeling – as complex as necessary but not more

Comparable and

exchangeable

Planned to be part of the ISI-MIP community, part of capacity development

Community Water Model

Feature Description

Flexible different resolution, different processes for different needs, links to other

models, across sectors and across scales

Adjustable to be tailored to the needs at IIASA i.e. collaboration with other

programs/models, including solutions and option as part of the model

Multi-disciplinary including economics, environmental needs, social science perspectives etc.

Sensitive Sensitive to the option / solution

Fast Global to regional modeling – a mixture between conceptional and physical

modeling – as complex as necessary but not more

Comparable and

exchangeable

Planned to be part of the ISI-MIP community, part of capacity development

CWATM Lake Victoria

WDFEI

1211 mm

MSWEP

1213 mm

Chirps

1192 mm

GSWP3

1170 mm

PGFv2

1190 mm Different gridded

datasets using

observed rainfall

data

Period:

1981-2010

CWATM Lake Victoria

Calibration of discharge for LV - precipitation

Annual mean

precipitation

National Water

Resources Assessment,

Ministry of Water and

Environment,

Uganda, 2013

CWATM Lake Victoria

Calibration of discharge for LV Calibration Jinja Pier

Objective function used:

Kling-Gupta efficiency (KGE)

KGE = 0.93

Nash Sutcliff = 0.86

R2 = 0.94

Bias = 1.5%

Objective function used:

Kling-Gupta efficiency (KGE)

KGE = 0.36

Nash Sutcliff = -0.47

R2 = 0.37

Bias = -9.7%

CWATM Lake Victoria

Calibration of discharge for LV Calibration Laropi

CWATM Lake Victoria

Precipitation

RunoffDischarge

Groundwater

rechargeWater demand

Next steps

• Water quality becomes more and more

important. This is particularly true for the

Lake Victoria where deteriorating water

quality already shows significant impact on

fish stocks and increases treatment costs

for water for domestic purpose.

Next steps: Water Quality

25

Next steps: GroundwaterEnergy intensity of water supply options

Data sources: Fan et al. (2013); Wada et al. 2014; hydroBASINS (2015).

Preliminary results

Conclusion• Water is cross-cutting. Consistent solution portfolios will need to be

identified that work across economic sectors, borders, and scales of

management.

• Water policy and management must be made a development

priority

• Linking science with practitioners:

Modelling based on robust but ambitious scenarios

On day 2 and 3

• Think through possible development pathways and solutions

• Benefit from robust water scenarios to support your decision

making for SDG / Country visions water resources planning

Thank you