Groundwater is a critical resource for most people who live in rural areas of the world. To put it in perspective, around three in every five rural households in sub-Saharan Africa rely on aquifers accessed by hand dug or drilled wells as their primary water source. We have previously written that the common ideal of rural water supply in developing countries is shifting away from point-source handpumps towards higher volumes of water provided in more convenient locations, namely with higher-capacity groundwater pumping systems and piped distribution networks. While Water Mission supports this ideal and is actively working with government and development partners to make it a reality, there is a potential complication to rapid expansion of rural water services.
We know surprisingly little about the sustainability of the Earth’s groundwater resources, particularly in developing countries. Global monitoring systems exist for hydrological phenomena such as precipitation, stream flow, and water quality – but not for groundwater. The British Geological Survey has devoted significant effort to cataloging what is known about availability of groundwater resources in sub-Saharan Africa through their Africa Groundwater Atlas initiative.
However, as was highlighted in this session at the 2017 Stockholm World Water Week, there is a general lack of data on groundwater withdrawal and recharge rates. This information gap is driving a growing concern that exploitation of groundwater resources paired with low or misunderstood aquifer recharge could lead to depletion of resources that have been relied on for centuries. The risk posed to rural populations because of uninformed groundwater development is often referred to as a “hidden” crisis because aquifers cannot be seen and the impacts are not understood.
Historically, there has not been a simple or cost-effective way to measure or monitor changes in aquifer volume at the global scale. Although pumping tests which are typically conducted to measure the sustainable yield of drilled wells are uncomplicated, they are labor intensive. Complex environmental and hydrogeological studies can give scientists perspective on aquifer recharge, but they are expensive and often inaccurate or inconclusive. These methods have limited scalability considering the global nature of the hidden groundwater crisis.
Furthermore, since current methods only provide insight into the status of groundwater resources at one point in time, they require significant ongoing investment to measure changes and predict long-term trends. There is a need for low-cost, scalable data collection systems which are capable of continuously monitoring withdrawal and recharge of groundwater aquifers for decades.
In collaboration with our partners at SonSet solutions and IBM jStart, Water Mission has developed a remote sensing system that enables effective and efficient monitoring of aquifer sustainability as well as rural water system functionality. The SatWater communicator can receive real-time data from any type of sensor such as flow rate, pressure, or oxidation-reduction potential (a proxy for chlorine residual) and transmit from anywhere in the world to a web-based data alerting and analysis dashboard called the MAP, or “Monitoring and Alerting Platform” (click here to read more about the development of the MAP and watch the following video demonstrating its functionalities).
The system brings acute technical issues and long-term performance trends to light, empowering managers to make actionable decisions and track responsiveness. Water Mission uses the system to monitor groundwater sustainability by mounting robust pressure sensors in drilled wells and measuring daily fluctuations in water level. The system triggers an alert if a significant decline in water level over time is registered.
Click here to view a diagram illustrating how sensors can be utilized to monitor functional and environmental sustainability of a rural water supply system.
Click here for more information and technical specifications on the SatWater communicator.
Water Mission’s remote monitoring system has strong potential to improve management of groundwater resources and enable expansion of rural water services because it addresses key scalability issues. Since the communicator utilizes satellite instead of a mobile network to transmit data, the platform is capable of rapid deployment without needing to negotiate multiple service agreements – SatWater communicators have been installed in ten countries to-date under a single global contract.
Furthermore, the total life-cycle cost of sensors and 10 years of data transmission is a few thousand dollars per water supply system – incremental when the far-reaching impacts of the data availability is considered. The challenge we face along with our field partners in realizing those impacts is to share and utilize the data, integrating remote monitoring data streams into established national and global monitoring systems and translating it into action.