Green Water Credits Report: Flying Sensors for Monitoring

Year of publication
Hunink J, Droogers P, van Til J, van Lynden GWJ
Green Water Credits (GWC) is an investment mechanism that supports upstream land and water users to improve water resources management for the benefit of all water users in a catchment. The funds for these payments are coming from the extra benefits of the downstream water users. A pilot project is currently conducted by ISRIC, FutureWater and partners to demonstrate and evaluate the possibilities of implementing Green Water Credits in the Oued de la Mina, which is a catchment of the Cheliff Basin in Northern Algeria.
Monitoring the impact of GWC practices on erosion control and vegetation is key to the success of any GWC project. Traditionally, monitoring is done at looking at streamflows and sediments loads, before and after implementation. However, with the advance in Flying Sensors techniques (sometimes referred to as drones or UAVs), detailed information on the stage of erosion can be obtained.
Overall, Flying Sensors can support the design and implementation of Green Water Credits, by:
1. Spatial inventories of GWC practices:
o Where certain practices take place?
o How do they change over time?
o Where adoption takes place, where not?
o Where are the “early adopters”?
o Diffusion of practices
2. Assess implementation properties of GWC practices
o Slope degree,
o Strip width, terrace intervals
o Tillage and contours
3. Monitoring effectiveness of GWC practices
o Soil moisture, soil organic matter
o Where do rills occur, does their appearance reduce/increase?
o Gullies – how do they evolve over time? Are they active, and which parts are most active?
o Monitoring landscape fragmentation and monitoring of habitats degradation.
o Monitoring of downstream water use, water consumption, water quality
GWC is currently explored and tested in various countries. For the case in Algeria specific interest exists in using Flying Sensors. Because of some practical constraints the methodology was tested and demonstrated in an area with similar environmental settings as the Cheliff Basin. For the Segura Basin in Southern Spain has been used.