Towards a Baltic Sea Region Strategy in Critical ... - Helsinki.fi

CRITICAL INFRASTRUCTURE PROTECTION IN THE BALTIC SEA REGION
awareness of an importance to protect groundwater resources, hinder pollution and
remediate possibly contaminated aquifers.
The objective of the case study is to provide an overview of the potential
risks of the shallow groundwater resources and water supply from both human
activity and climate change, including risk management in one coast area aquifer.
The results obtained from the particular object of this case study can be applied to
other similar aquifers, as it outlines possible threats that would impact shallow
groundwater resources, considering the implications for the management of water
resources in different sectors. The specific risks and threats to a seashore aquifer
are changes in present sea water level, contamination of salt-water intrusion, and
future sea level rise and change in precipitation and evaporation caused by climate
change.
In the empirical part of the case study, groundwater level monitoring data in
two observation wells of 30 minutes intervals and the sea level monitoring data of
60 minutes intervals were produced in the Hanko case study area. Based on this
data, it was – for the first time in an empirical study in Finland – observed that the
sea level changes have a direct and very fast effect on the groundwater level. The
effect was worse in that part of the Hanko aquifer where the permeability of sand
and gravel layers was high. According to the climate change scenarios, the
significant rise of sea level in the Hanko coastal area could cause problems to the
water supply managements and infrastructure planning in the Hanko and in many
other coast aquifer areas.
On the basis of these notions, the case study proposes a conceptual model for
protection of shallow groundwater aquifer for the Hanko and other coastal areas
aquifer. In order to assess the new risks and threats, it is essential to establish a
new risk management scheme. The detailed plan for groundwater protection is the
most significant tool in the risk assessment and risk management. The plan should
be prepared accurately and all the special factors based of the vicinity of sea
should be considered.
Detailed studies of stratigraphy in aquifers and groundwater flow models,
groundwater recharge and discharge, in correspondence to either the present
climate situation or the different scenarios due to climate change, have to be done.
Also, the detailed mapping of all risks or potential risks may be constructed.
Groundwater level and groundwater quality monitoring in range of the
contaminant is significant. Monitoring includes also biological and
microbiological monitoring, especially during long hot dry summers. New
technologies in online measurements have progressed substantially in recent years,
so automatic monitoring is a good option.
Concrete short and long term strategies on potential economic and
environmental effects have to be taken into account. Long term investment and
management plans for the infrastructure of the water supply and management,
such as use of more durable material and long life span for the water supply
network, can ensure capacities for the unforeseen effects of the climate change in
the near future.
On a larger scale, groundwater issue is not solely local or national in the
cross-border aquifer areas, such as in eastern Finland, where the groundwater
aquifer from the First Salpausselkä formation extends to Russia. In this and similar
cases, cooperation on the groundwater management between countries is needed.
XXVIII NORDREGIO REPORT 2007:5