The GWB project “Hydrogeophysics for Community Monitoring of Groundwater in Degraded Dry Forest Quebradas of Peru”— deployed by EcoSwell, local nonprofit for-impact organization — is in the district of Lobitos, within the Talara province of Piura region in northern Peru. This region features a hyper-arid climate that gives rise to a unique ecosystem known as the ‘Bosque Seco’ (Equatorial Dry Forest). Unfortunately, human impact has resulted in widespread desertification and degradation of this landscape, with Lobitos and other surrounding communities suffering from ongoing water stress.
This project’s primary objective is to empower local communities by providing them with the knowledge and geophysical tools necessary for monitoring groundwater. The EcoSwell team is working with and training people not only in Lobitos but also representatives of three neighboring communities (Síchez, Piedritas and Fernández), as well as local and regional governments, and local watershed council and water authorities.
The local project team, led by Diego Almendrades (Project Manager), received valuable technical mentorship from expert partners in the UK: Prof. Andrew Binley from Lancaster University and Dr. Lai Bun Lok from University College London. With help from their students, the experts assembled three low-cost geophysical instruments – resistivity, seismic, and ground-penetrating radar, which were imported to Peru. The local team then hosted the experts in Lobitos, where they tested and got trained in the use of the equipment in the field, to ensure surveys were appropriate for collecting valid data. Afterward, the local team successfully translated, transferred, and delivered theoretical and field training on the low-cost resistivity meter to 17 local people, including representatives from all four rural communities and public officials.
During the field training sessions, data was gathered from a demonstrative “quebrada” site in Lobitos to draw a model. Quebradas (also known as “wadis”) are dry valleys in the desertified landscape, which the Dry Forest vegetation tends to follow and where any superficial water will run during rare intense rain events, often creating flashfloods that make their way to the ocean. Quebradas can extend for several kilometers, and they are the lowest point in the elevation profile, therefore any groundwater will be shallower there. Quebrada Monte in Lobitos was surveyed at eight targeted locations, covering more than 4 km (approx. 2.5 miles) inland from the coastline.
With these results the team was able to gather not only an estimation of the depth to the water table at each point (less than 10m), but also an estimation of the groundwater’s salinity at each point, due to resistivity (and hence conductivity) measurements obtained.
Creating a model for this quebrada served as an example while teaching people how to replicate this in their own communities and local quebradas. The project team and the people trained were able to identify a location, approximately 3.5 km (2 miles) from the sea, where the conductivity and estimated salinity dropped sharply. This inferred “salinity threshold” or frontier, together with the depth estimation, is valuable information to better inform future boreholes and wells’ locations. With this new knowledge and low-cost equipment, these marginalized communities can now save money which would otherwise be needed to pay companies for costly surveys. They can now be better informed in selecting a location before investing in drilling a well. Eventually, these pastoral communities can improve their quality of life with this new water source (after appropriate treatment) by using it responsibly in regenerative grazing to restore the ecosystem and reverse desertification.
During all the project activities, 15 other international and national students have been involved as volunteers, both remotely and in-person in Peru. They produced manuals, training materials, videos, and social media content to help spread and grow interest in applied geosciences.
In the final workshop of the project, the team achieved a significant milestone by producing a Letter of Intent (LoI) signed by local stakeholders and participants. In this LoI, the communities committed to engage local authorities for future projects and the authorities committed to create new public jobs for the trained community members as community groundwater monitors and to promote agreements with EcoSwell for new groundwater projects. This is the long-term legacy of the work done under this GWB project.
Article by Diego Almendrades- Project Director- EcoSwell (Project Lead)