270 likes | 399 Views
Aquifer committees and groundwater over-exploitation. Case Study: The State of Guanajuato Mexico. The state of Guanajuato. Area: 30,768 km 2 of which 83% belong to the Lerma Chapala Basin (44% of the area of the basin). Population: 4.7 million 3.1% GNP of the country 480,107 irrigated
E N D
Aquifer committees and groundwater over-exploitation Case Study: The State of Guanajuato Mexico
The state of Guanajuato • Area: 30,768 km2of which 83% belong to the Lerma Chapala Basin (44% of the area of the basin). • Population: 4.7 million • 3.1% GNP of the country • 480,107 irrigated ha (60% of it with groundwater) • Severe groundwater exploitation problems
Groundwater exploitation in theLerma Chapala Basin • Red areas are overexploited • Darker blue in balance • Light blue under used • Note the state of Guanajuato (Most red areas)
2,778 4,027 Groundwater RECHARGE TOTAL ABSTRACTION Deficit -1,249 Intense groundwater use • All aquifers are being mined and water extractions are still increasing (4000 MCM/year with a deficit of 1250 MCM/year) • High productivity and forward-linked export agriculture. • Growing urban and industrial water needs
Deep wells year Intense water use Number of wells is still increasing
Consequences of overexploitation • Average aquifer decline of 2.03 m/year (with extremes of 5 m/year) • Increasing pumping costs • Decline in groundwater quality • Subsidence (up to 3 cm/year) Subsidence
What has been done before to regulate groundwater? • Historical responses to regulate groundwater • Vedas bans on new wells • 1956 (Groundwater users are required to get permits/concessions) • Since the new water law (1992) regularization of groundwater concessions (REPDA)
What has been done before to regulate groundwater? • Current programs to register wells with an annual volumetric concession. BUT • Ineffective in controlling groundwater exploitation
improve institutional settings aquifer management programs import water implement adequate technology raise agricultural productivity efficiently satisfy growing public needs improve and sustain human capacities rescue water volumes implement water exchange schemes reform financial structures promote good- practices-enabling social values preserve sources and ecosystems reclaim wastewater What is being done
What are COTAS • MSP’s (Multi Stakeholder Platforms) at aquifer level aimed at organizing users in aquifer management councils to reach agreement on reductions in extractions
What are COTAS • All water users of an aquifer can become a member of COTAS, multi-sectoral • (1997-2000) 14 COTAS + 1 coordinating institution CEH (Consejo Estatal Hidraulico) Guanajuato
Structure of the COTAS TECHNICAL EXPERTISE SOCIETY (Organized Water Users) GOVERNMENTAL SUPPORT COTAS Water Technical Council General Assembly Directive Board Consultative Group Technical Group Technical Committee - Guanajuato State’s Trust for Social Participation in Water Management (FIPASMA) Manager Administrative Suppport Technical support
Outputs of COTAS • Technical support to users • Studies and mathematical models of all aquifers • Institutional development • Communication of a “water culture” • User-oriented services
Challenges and opportunities • Challenges • Low participation (2-3% of total users) • Lack of legal faculties (no enforcement faculties)= works on the good will of users • Has had little effect on groundwater extraction levels
Challenges and opportunities • Opportunities • Strong state government support (CEAG) • Increasing awareness of users • 15 formed and functioning institutions
Lessons learned • Participation is difficult when users don’t see direct benefits. • Is 1000 or more users for one COTAS too much? • The lack of legal power to enforce control and measures is an important constraint. COTAS could play a role in titling, eg, through responsibility and supervision of group concessions. • User awareness is slowly increasing; this creates a base for action.
Water use in agriculture • Rationale: higher irrigation efficiency will reduce groundwater use • Programs • Modernization of groundwater irrigation systems • Plot leveling
How does it work • Farmer applies for subsidies for improving his irrigation technology (requirements) - Legal groundwater use permit • Contribution of the farmer (10%-50% of total costs) • With the new project flow meters are installed on pumps
How does it work • State Secretary of Agriculture (SDA) reviews the application • The project gets approved and installed • Farmers are responsible for the proper installation of technology, if it is not well installed the state does not pay. • Subsides get liberated (paid by the federal and state governments when to work is approved and completed)
Results of the programs • Total investment 1,2 milliondollar • Benefited users 35,500 • Hectares 173,000 ha • Effects • More efficient groundwater use • Higher agricultural outputs • No significant groundwater use reductions
Lessons • Increasing irrigation efficiency raises agricultural production but does not necessarily decrease groundwater exploitation • Raising irrigation efficiency to reduce groundwater use is only effective if there is strict control over pumped groundwater volumes
Energy pricing • Concessioned wells receive energy subsidy up to concessioned volume - enforcement difficult. • All power connections for wells require proof of concession title. • Energy tariff fixed at Mex$ 0.30 (US$ 0.0316) per kWh up to annual energy consumption limit based on concessioned volume.
Energy pricing • Supply manipulation options unfeasible: • restrictions on new connections • caps on capacity or amperage, and • reductions in hours of power supply • Pricing options...
Conclusions • Groundwater management is a key challenge that requires regulatory and participatory approaches coupled with changes in demand behavior of pumpers. • Institutions have to work together with each other and with the users to reach agreements on how to reduce groundwater use.
Conclusions • The enabling legal and human resources to impose strict control are not always available so other options have to be devised. • The options are many… but which one(s) will work? • Can different strategies be combined to fit the specific needs established by a specific context?
Acknowledgement This case study is based on: Jaime D. Hoogesteger van Dijk ‘The Underground; Understanding the failure of intitutional responses to reduce groundwater exploitation in Guanajuato’ (Wageningen University, The Netherlands) Pictures made available by Jaime Hoogesteger van Dijk. With special thanks to: the CEAG (www.guanajuato.gob.mx/ceag/) and SDA for making the information available.