Ica is located on the South Coast of Peru and counts on the most advanced agro-industrial development of the country. Agricultural production depends on groundwater availability, and since 2012 JUASVI and ANA have implemented more than 700 infiltration ponds for intermittent use. So, it has become one of the largest scale MAR systems in America, and it is providing lessons beyond those from pilot-size sites.
MAR is combined with different IWRM techniques, providing an example about MAR is a piece of a multi-component system, not able to solve water scarcity and drought situations by itself, but the technique becomes powerful when it is combined with additional water harvesting and management multipronged resources and mechanisms.
Water is taken from Ica River during the rainy season, stopped by specific constructions, retained in decantation ponds and later directed at infiltration ponds (pozas) interspersed along the aquifer.
Some specific lines of action to improve the system already applied are:
- Structures to retain water from Ica River minimizing the volume finishing in the Ocean
- Over-floods management with a certain predictive component
- Aquifer knowledge and its behavior improvements, so as to set new infiltration ponds in the most suitable sites
- Creation of an integrated and interconnected water management system
- Monitoring network in real time
- Clogging fight and high efficiency maintenance operations
- Search for alternative sources of water such as WWTP, transferences, irrigation return, etc.
- Coordination and communication improvement
Some alternative lines of action are based on the use of gravity dikes, underground dykes, river basin´s slopes treatment and SUDS.
It is also worth to mention the support of local authorities and difficulties to reach agreements between the different agents within the basin (from the mountain to the sea) which have different interests leading to eventual water conflicts. Apart from the technical and social barriers, the total dependence of rainfall is forcing to seek new sources of water and alternative mechanisms, from WWTP to SUDS implementation.
MAR is in the Peruvians idiosyncrasy (Incans recharged intentionally from at least the XII Century), so, by means of single surveys, it is possible to find out new susceptible areas to build new “pozas”. In seven years of operation it is worth to mention that clogging damage is not remarkable yet, infiltration rates have barely changed and cleaning and maintenance activity is inviting to new owners to provisionally loan their terrains for new infiltration ponds.