1. Availability of water resources under climate change in SE Europe
Climate Change and Impacts on Water Supply
supported by ERDF and IPA
Availability of water resources under climate change
in SE Europe
Zoltán Simonffy
Department of Sanitary and Environmental Engineering
Budapest University of Technology and Economics

2. Climate Change and Impacts on Water Supply
Countries:
Austria
Bulgaria
Croatia
Greece
Hungary
Italy
Romania
Serbia
Slovenia
15 partners

3. Climate Change and Impacts on Water Supply
General objective of the EU water policy:
Safe, healthy drinking water supply
for long-term!

4. Climate Change and Impacts on Water Supply Objectives of the project:
to assess the impact of CC (and CC induced land use
changes) on water resources used for drinking water supply
and on water demand;
to evaluate availability and safety of public drinking water
supply for several future decades (risk assessment);
to delineate critical areas where measures are needed;
to propose management options (decision support for
suppliers and authorities);
to propose methodolgy for such assessment

5. Climate Change and Impacts on Water Supply
Structure and methodology:
Climate change (WP3)
WP4
Meteorological and hydrological chracteristics
Quantity and quality of water resources
Ecological and environmental criteria
Water demand
Economic assessment
WP6
Water Supply Management (WP7)
Proposals and tools
Land use & water quality (WP5)

6. Climate Change and Impacts on Water Supply
WP4
Availability
of water resources

7. Assessment is based on 19 test areas
Climate Change and Impacts on Water Supply
Assessment is based on 19 test areas

8. Climate Change and Impacts on Water Supply
Modular structure
Precipitation
Water balance
model
Surface runoff,
flow in the river
Recharge
Sprigs
Baseflow
transpiration
Evapo-
Groundwater
flow model
Lateral flow to
neighboring grwbody
abstractions
Surface runoff
MODELLING MODULES
available
discharge
spring flow available for capture
available grw.
for abstractions
Evaluation
of available
groundwater
resources
EVALUATION MODULE
+ IMPACT
OF CLIMATE CHANGE AND LANDUSE
ecological
criteria
ECOLOGICAL MODULE

9. Stucture of models (example)
Climate Change and Impacts on Water Supply
Stucture of models (example)
Precipitation
Groundwater level
Topography (slope)
Landuse, Soil type
Discharge in river
(separation of surface runoff)
Hydrogeological data
Water courses
Water abstraction
Shallow and deep ground water level
Baseflow
input
calibration
input
calibration
Flux at gw level and baseflow
harmony
Water balance model
of the unsaturated zone
Hydrodynamic model (3D)
(MODFLOW)
Surface runoff, flux at gw. level (evapotranspiration, recharge)
Gw. level, glux at gw. level, baseflow,
exchange with neighbouring aquifers

10. Ecological criteria Climate Change and Impacts on Water Supply
Groundwater dependent ecosystems:
Swamp
Swamp-meadow
High water demanding marsh
Marsh-meadow
Wet salt-marsh
Dry salt-marsh
Riverside forest
Gw demanding forest
ETA needed from grw.
Critical depth
acc. to required fluctuation
Surplus of evapotranspiration from groundwater at the wetland
and in the surrounding area (too)

11. Changes in meteorological conditions
Climate Change and Impacts on Water Supply
Changes in meteorological conditions
Blue: Westren part: Austria, Slovenia
Green: Middle part: Hungary, Romania
Southern part: Croatia and Serbia
Summer
Winter

12. Changes in meteorological conditions
Climate Change and Impacts on Water Supply
Changes in meteorological conditions
Blue: Westren part: Austria, Slovenia
Green: Middle part: Hungary, Romania
Southern part: Croatia and Serbia
Annual

13. Changes in water resources
Climate Change and Impacts on Water Supply
Changes in water resources
Blue: Westren part: Austria, Slovenia
Green: Middle part: Hungary, Romania
Southern part: Croatia and Serbia
Precipitation – pot. ET [mm]

14. Climate Change and Impacts on Water Supply
Conclusions
by regions
HU, karstic springs:
No channge, but
ecological water demand is already problematic
HU, porous aquifers:
Considerable decrease,
Shortage is likely, ecology already
AT, karstic springs:
Large system: no problem of quantity
Small springs: possible shortage (low flow)
 new resources (available)
SI, porous aquifers:
Slight decrease,
No problem of quantity
RO, porous aquifers:
Slight decrease
No problem of quantity
RS, alluvial aquifer:
Considerable decrease,
Possible shortage.
RS: small karstic springs:
Slight decrease,
Possible shortage at low flow
CR, karstic lake, fields:
Considerable decrease,
Seawater intrusion already,
shortage is likely,

15. Climate Change and Impacts on Water Supply
General conclusions
Different sensitivity indexes related to CC and drought
(i.e. How does CC modify them?):
recharge and available water resources
GWDE (ecological water demand / recharge)
extremities (droughts and „flash floods”)
global exploitation, frequence of shortage
Clear presentation and possible decrease of uncertainties.
Revision (understanding) of ecological water demand (source of conflict)! Research based on case studies.
Evapotranspiration is a key factor in the estimation of the recharge and the water demand of ecosystems. Research is necessary!!

16. Competition or adaptation? Thank you for your attention