Shallow groundwater wells, are the main source of drinking water in many rural and peri-urban communities.
The quantity and variety of shallow wells located in such communities make them more readily accessible than private or government operated deep boreholes, but shallow wells are more susceptible to faecal contamination, which is often due to leaching pit latrines.
For this reason, online monitoring of water quality in shallow wells, in terms of faecal pollution, could dramatically improve understanding of acute health risks in unplanned peri-urban settlements.
More broadly, inexpensive online faecal pollution risk monitoring is also highly relevant in the context of managed aquifer recharge via the infiltration of either stormwater or treated wastewater into the subsurface for aquifer storage and recovery.
To tackle this challenge, IN-GROUND – an UPGro Catalyst Project – trialled four different types of Microbial Fuel Cell (MFC) water quality biosensor in the lab (Newcastle University, UK) and in the field (Dar Es Salaam, Tanzania).
While further work is needed, the results provided proof-of-concept that these biosensors can provide continuous groundwater quality monitoring at low cost and without need for additional chemicals or external power input.
Dr Sharon Velasquez Orta (Newcastle University) has been recognised by the MIT Technology Review as one the leading “Innovators under 35” for 2015 for her work on developing a low-cost biosensor of measuring groundwater quality. In the UPGro Catalyst project (INGROUND), she and colleagues from Newcastle University and Ardhi University have been developing the sensor in the lab and trialling it in Tanzania:
“Her biosensor detects fecal contamination in water reserves destined for human consumption”
“In low resource areas, like sub-saharan Africa, the absence of water quality data poses a serious risk. For this reason, Sharon Velasquez has harnessed the degradation process undertaken by some organic bacteria to generate electricity which allows her biosensor to detect fecal contamination within the water source.
“The microbial fuel cells (MFC) that Velasquez uses work like batteries, the difference being that with MFCs the current flow is generated by the electrically charged components that batteries produce upon charging.
“In this way it is possible to create sensors that detect the organic material present in the medium as the bacteria begins to metabolize the organic material.
“Velasquez´s biosensor is characteristic due to its cylindrical shape which allows the resulting chemical reaction to happen directly in the environment.
“This technology aims to address the issue of fecal contamination of water supplies, given that this cannot be continuously controlled via existing systems because the detection process is lengthier and requires greater human resources.”
The INGROUND project is due for completion later this year.
The meeting brought together the UN agencies working in water and invited stakeholders from governments, business, civil society, academia and the media to talk about water scarcity and water quality, risk and risk management and WASH in terms of lessons learnt from the Waterforlife Decade and the Millennium Development Goals (MDGs) and to take them forward to the Sustainable Development Goals (SDGs).