Workshop on climate risk and
water security in the Americas
Patricia Romero-Lankao
March 1, 2011
Water security at risk from multiple
stresses and…. 2. Example
The Hydro-polis of Mexico City
1. Overdrafting/pollution
of water bodies
–
Extraction from 23.5 (1990)
to 25.8 m3/s (2005)
2. Competition among users and
basins
1. Example: Basin of Mexico City, water balance
Annual
precipitation
213 m3/s
226.7 m3/s
(746mm)
Evapotranspiration
171 m3/s
163.2 – 179.1
m3/s
Source: Romero Lankao (2010)
Aquifers
recharge
23 m3/s
29 m3/s
Surface
runoff
19 m3/s
29.1
m3/s
Availability
40 m3/s
48.1 m3/s
Overexploitation
22.2 m3/s
19.1 m3/s
Path dependency/legacies from the past
4. Governance
(institutional frameworks)
3. Extremes
Mexico City: hydrometeorological events resulting in
disasters (1980-2006 )
• Water publicly own (State/
nation)
1%
Flood
5%
6%
8%
0%
Frost
Heat-w ave
6%
Storm
Rain
Hail-storm
3%
6%
65%
Wild-fire
• Private participation (service
contract)
• CNA defines national policies
• Fragmented administration and
participation
Drought
Cold-w ave
Source: Romero Lankao (2010 ) Own calculation based on data from La
Red (2008), Desinventar http://www.desinventar.org/
• Insufficient investment mostly
focused on new (visible) works
• Not addressed through water
reforms
Priority challenge “stationarity of risks is
dead”
• Up to 4°C increase in
mean temperatures
• Up to 20% decreases in
mean precipitation
• Stress on already limited
water resources
• Alternation of more
intense droughts intense
and excessive rain
• Yet, lots of uncertainty
Source: INE (2009)
How to address these challenges:
Risk Governance in a Non-Linear World
• New paradigms, e.g.,
conceptualization of risk
• Scientific endeavors
– Sensitive to context
– Integrate disciplinary
domains
– Framing (credible and
salient)
– Aware of cultures &
priorities
– Institutionally enhanced