Integrated water resources management on a local scale: a challenge for the user community—a case study in Southern Spain

Abstract

Associated with the vision of balanced, sustainable resource management, the end of the 20th century witnessed the paradigm of Integrated Water Resources Management (IWRM), whose application was based on considering the river basin as an operating unit. The last decade has seen a preference for a scaled abstraction of this focus in which the administrative and physical limits of the resource that is provided can be considered as water management subunits, albeit ever dependent on and under the supervision of the river basin authority to which it belongs. This article shows the advantages of applying specific IWRM-based measures that can be implemented on a local scale. In the case under study (a municipality in southeastern Spain) and based on the possibilities it offered, consideration has been given to joint management of the available water resources as feasible from the technical, economic, social and environmental points of view. The project compares two 20-year scenarios to reflect the consequences of incorporating the overexploited aquifer into the local water resources management scheme. Scenario 1 represents the existing non-joint water management, while Scenario 2 considers conjoint water management of surface and groundwater resources, examining variables related to climatic change and economic cycles. The simulations performed demonstrate that local scale management appears to be a feasible solution for semiarid towns and villages: it increases supply compared to current management and guarantees that demand is met for all the irrigation communities and indicates an almost immediate widespread recovery of the water table, even under scenarios with increased demand and a moderate fall in water resources.

Cost-Benefit Analysis of the Managed Aquifer Recharge System for Irrigation under Climate Change Conditions in Southern Spain

“…This work complements the studies carried out by Senent et al [17], Pérez-Sánchez and Senent-Aparicio [18], and Rupérez-Moreno et al [19] in the Boquerón aquifer. The scenarios found in these studies have been updated and include the effects of climate change.…”

“…These factors are crucial to agricultural development in the region, which has grown due to the recent economic crisis in Spain. In fact, more than 20% of the workforce is currently employed in the agricultural sector [18]. This has led to an increase in the water demand in this municipality.…”

“…However, due to the seasonal nature of demand throughout the years, the surpluses in the Hellín canal between the wettest months from October to April (3.67 hm 3 /year average) are not used or stored by the municipal water system, and it loses the power to regulate the resources awarded by the river basin authority to which it belongs. Similarly, in summer (June-September), there is a high deficit in the irrigation activities (8.66 hm 3 /year average) associated with the canal, and they are compensated by water from different aquifers, especially the overexploited Boquerón aquifer [18]. From a hydrogeological point of view, the Boquerón aquifer is an important water storage method because it consists of dolomitic fractured bedrock coming from the Chorro age with an average thickness of 300 m, porosity between 3% and 8% and permeability around 1.15 m/h according to IGME [20].…”

“…It is capable of simulating the joint management of water resources, as it enables the incorporation of aquifers into the surface water subsystem as another regulation 'deposit'. Two different management water scenarios have been designed: (scenario 1) current management with no interrelation between surface and underground water (business as usual); and (scenario 2) joint management that includes the aquifer of Boquerón as a 'large underground regulation deposit' through recharges using the Hellín canal surplus, as produced in the system [18]. This will make it possible to compare each of the proposed scenarios.…”

“…The demands are introduced as average monthly values. Once the elements of the system and the relationships between them have been configured [18], the model is defined as an optimization problem that can be expressed across a target function and a set of limitations [27] and is solved using the Out-of-Kilter algorithm [28]. Aquifer recharge was obtained with Visual Balan [29] for both emission scenarios.…”