Groundwater Management or Mismanagement in Mexico?
Luis E. Marin
&
Oscar A. Escolero F.
Mexican National University
Arid and Semi-Arid Governance and Management Workshop
Cairo, Egypt April 3-8, 2005
Legal framework for water
Article 27 of the Mexican Constitution
All goods found in the subsurface belong to the nation
Interpreted as “Constitutional right to free water”
Limited Access to information
Comisión Nacional del Agua (CNA), and other federal, state, and local agencies
Government agencies used to control many professional organizations, thus, no
“independent opinions” were available
2004: “Freedom of Information Act”
Importance of Groundwater to Mexico
653 aquifers
200 have been thoroughly studied
104 (or ~150) severely over-exploited
Provides 70% of drinking water to cities
75 million inhabitants (73% urban and 27%
rural)
57% used for agriculture (one third of the total)
Spatial and temporal distribution of water in Mexico
Precipitación Media Anual DE 0 A 125mm DE 125 A 400mm DE 400 A 600mm DE 600 A 800mm DE 800 A 1,200mm DE 1,200 A 1,500mm DE 1,500 A 2,000mm DE 2,000 A 2,500mm DE 2,500 A 4,000mm MAS DE 4,000mm
hab/km2 0 - 20 20 - 50 50 - 100 100 - 500 500 - 1,000 1,000 - 5,000 más de 5,000
Distribution of rainfall Main population centers
Over-exploited aquifers
no sobre-explotado sobre-explotado
AGRICULTURA DE HUMEDAD AGRICULTURA DE RIEGO
AGRICULTURA DE RIEGO SUSPENDIDA AGRICULTURA DE TEMPORAL
AGRICULTURA NOMADA
no sobre-explotado sobre-explotado
Main Agricultural Regions and Overexploited Locations
Water Quality in Mexico
Groundwater availability for drinking water (based on water
quality)
Surface water quality
Arsenic and lead contamination
Six year old = four year old size result of: Under nutrition,
combined effect of metals Stunted Growth
Stunted Growth
Potential solutions to decrease aquifer over-exploitation
40 45 50 55 60 65 70 75 80
Electric consumption GWH/year Hundreds
0 0.1 0.2 0.3 0.4 0.5 0.6
Tariff $/kwh ($1980)
1982 1984 1986 1988 1990 1992 1994 1996 1998
Year
Consumption Tariff
Tariff deflacted by using the implicit price index of GDP
GW Governance in Mexico
1950-1970´s: Water was controlled by technicians (Basin Commissions)
1970´s-present: Policy-makers
The future: stake-holders
COTAS (Technical Committees for GW management)
Basin Councils
Science-based decision making
Perry, et al., 2002
Effects of aquifer over-exploitation
0 10 20 30 40 50 60 70 80 90
1910 1940 1950 1960 1970 1980 1990 1995 2000 2010 2020 m3/s
Mexico City Aquifer Lerma basin
Cutzamala basin Deficit
Springs of Mexico City
*
The present water supply is 62 m3/s.
Every year
population growth demands an
additional
0.72 m3/s above the current deficit of 7 m3/s.
The Mexico City Example
Water Network of the Mexican Academy of Sciences
Contribute to Mexico´s growth and to the well being of its citizens, through the sustainable and integral use of surface and ground water management through science
Science-based resources
Inter Academy Panel on International Issues (IAP)
TWAS: Academy of Sciences of the Developing World www.twas.org
Capacity building
Grants, Visiting professorships, etc
African Academy of Sciences (AAS)
Third World Network of Scientific Organizations (TWNSO)
Safe Drinking Water Network
Inter American Network of Academies of Science www.ianas.org
Science (Academies)
Using Science to help people
AMC-NAS Science- Based
Decisionmaking for sustainable GW management
Capacity building
0 5 10 15 20 25 30 35 40 45
MS PhD
Degrees
UNAM 2002 1992
Policy Makers Society
