Introducing the Case Study Areas: Hydro-climatic and Governance Contexts - Climate Change and Water Governance: Adaptive Capacity in Chile and Switzerland - page 117

Table 6.3 Detail of impacts on separate categories of water goods and services per each extreme event
Case event:
geomorphological impacts Impacts on water goods & services

Production

Energy Environmental fl ows Transport & absorption

of ef fl uents

Domestic use: water
supply & sanitation

Heat waves/drought
Permafrost degradation &
reduction in the cohesion
of slope material,
acceleration of glacier
retreat, reduction in
snow pack

Heat stress, enhanced
evaporation, droughts,
soil-moisture depletion,
acceleration of glacier
retreat (could lead to
decreased or increased
run off depending on the
state of glacial retreat)

Changes in hydro-power
supply because
of seasonal shifts
in the filling of dams
in the Swiss case
and river flow in the
Chilean case

Damage to eco-systems
through excessive heat
& drought

Reduced fl ow increasing
concentration
of chemicals in water
ways

Despite reduced fl ows,
drinking water is
prioritised during
drought situations in
both areas (in Chile
only once an official
Presidential
Declaration of
drought)

Drying up of river beds,
streams and estuaries

Winter warm spell/drought
Enhanced avalanche risk

Decreased snow availability/
seasonal snow cover

Changes in hydro-power
supply because
of seasonal shifts
in the filling of dams
in Swiss area

Early start of the
vegetation cycle

Reduction of mid-winter
snow pack negatively
impacts water
reserves for the
recharging springs
with melt

Early run off into alpine
river basins

Without the buffering
effect of snow, a heavy
downpour can become a
catastrophic event,
low precipitation
Extreme precipitation Sediments deposited

in large quantities
on agricultural lands,
irrigation canals and
streams - reductions in
agricultural production

Erosion, discharge &
sedimentation
rates - damage
hydropower
infrastructure

Increased fl ows causing
over fl ow of waste
waters into
water ways

Excess debris can
negatively impact
water treatment
plants and canalisation
infrastructure

Slope instability events
in mountain regions,
increased frequency
and severity of floods

Source: Beniston ( 2005a, b ) , Beniston et al. ( 2007 ) , Kundzewicz et al. ( 2007 )