Transcript Dealing with the blind, the hidden and the unconscious as sources

Groundwater quantitative
status in Denmark
Hans Jørgen Henriksen
Climate change and adaptive water management in EU and beyond. Vingsted March 9, 2009
Session 1 – EU Water Framework and Groundwater Directives in a changing climate
List of content
•
WFD and groundwater directive
•
Policy recommendations for groundwater exploitation:
groundwater levels, water quality and aquatic habitats
•
Translating qualitative policy recommendations into quantitative
criteria in the Danish NOVA 2003 assessment
•
Results of 2003 assessment
•
Discussion – adaptive and integrated water management?
•
Conclusion
WFD and Groundwater Directive
•
Objectives:
– Good status of surface waters (ecological and chemical) and
groundwaters (chemical and quantitative)
– All aquatic bodies are concerned: rivers and streams, lakes,
groundwaters, coastal zone, wetlands…
– The good status of 2015 has to be reached – going in the right
direction isn’t sufficient
– If not possible to reach goals in 2015 =>
• Delays to 2021 or 2027
• Reframing to less strict objectives
(in both cases justified technical and economical)
Winter precipitation and groundwater level
Groundwater
level (m)
Winter precipitation
mm
Winter precip.
3-year
average value
South Jutland:
Zealand:
Groundwater quality and groundwater
abstraction
Requirements for groundwater
discharge to aquatic environment
Max reduction of low flows
Depending on ecological
Objectives of river reach:
A : max 5 %
B1: max 10 %
B2: max 15 %
B3: max 25 %
CE: max 50 %
Four quantitative sustainable yield
indicators (NOVA 2003 assessment)
Ensemble approach (Jakeman and
Letcher, 2003, Henriksen et al. 2008):
Assessment of sustainable yield and scale
Precautionary principle: Indicator 1 : 35%
Nickel
> 10 μg/l
> 20 μg/l
Others:
Chlorite,
sulphate
hardness
Sub area
Area
Exploitation
rate
River reaches and environmental flow
Selected indicators and climate
Climate variation and indicator 1-3
Results for different areas
Result of assessment for Denmark (2003)
Sustainable yield
Current abstraction
Subareas
Exploitation rate (%)
More information: Henriksen et al., 2008:
Discussion
Scientific recommendations:
Validate the quantitative criteria,
based on monitoring data!
Ex post validation of quantitative
criteria
(max. reduction of min. flow incl. waste water
discharge)
< 10 km2
10 – 50 km2
> 50 km2
Max. 5 %
Max. 10 %
Max. 15 %
60.17 Rødlersbæk:
60.12 Herredsbæk:
-90,6 %
?
51.06 Svinninge å:
51.10 Elverdams å:
60.04 Mern å:
48.04 Højbro å:
56.02 Harrested å:
60.13 Lille å :
59.05 Krogbæk:
52.07 Græse å:
60.05 Vivede m.å:
51.08 Kalvemode å:
-30,3 %
-5,6 %
4,3 %
4,4 %
6,3 %
6,5 %
9,0 %
10,2 %
14,2 %
17,6 %
55.06 Åmose å:
57.37 Flads å:
56.09 Seerdrup å:
56.15 Tude å:
59.01 Tryggev.å:
52.08 Havelse å:
56.10 Bjerge å:
-11,8 %
- 2,1 %
3,5 %
3,6 %
10,1 %
14,6 %
14,8 %
Ensemble resource indicators and
modelling can be used as tools for
adaptive water management
Policy recommendations:
Adaptive water management: use
higher learning levels
Doing things better
(reducing water consumption:
Improving irrigation efficiency)
How to do better things
(adjusting land use & crops;
Improving water quality and
Aquatic habitat conditions)
Adaptive management can be defined as a
systematic process for improving
management policies and practices by
learning from the outcomes of implemented
management strategies
(www.newater.info)
Social learning
Water users and farmers starting
to see things differently. Improved
spatial perception and understanding
of the aquifer, and the importance
of groundwater, as part of the whole
system (supplying wetlands etc.)
What is required if water resources
should be managed by adaptive water
management (in learning processes)?
NeWater
Guidebook:
Lessons
Learned from
7 case
studies
Conclusions
•
Total available water resource is in balance with abstraction on the national level, but
the nationwide resource and exploitation is unevenly distributed, and is fluctuating in
time =>
– Over-exploitation around Copenhagen, Århus and Odense and for intensive
irrigated areas in western Jutland due to regional variations in available resource &
water uses
– Extreme droughts and climate variation is important for exploitable resource, and
for the state of the groundwater dependent ecosystems. Minimum flow reduction
most critical barrier for groundwater exploitation
•
The four ensemble indicators should be further validated based on monitoring data.
Linked to the scale they have been applied. Approved more generic indicators could be
scaled for < 10 km2, 10-50 km2 and > 50 km2 (max. 5, 10 and 15 % reduction), where
15 stations on Sjælland documents good ecological status with abstraction in these
ranges. Further development, tests, validation and documentation is needed
•
Adaptive management is recommended as a way to allow higher order learning
(double & triple loop) from groundwater systems, and in order to increase
buffering capacity and adaptive capacity of the whole system. This is also
an advantage in order to plan for adaptation for climate change
What we don’t want from the future:
A duck stuck in a boat on a river…
Foto: HarmoniRiB, CEH (UK)