The Sustainable Groundwater Development theme has the longest history in RWSN, building on:
Handpump Technology Network (HTN) - launched in 1992
Cost-Effective Boreholes flagship of RWSN - commenced in 2004
UNICEF’s initiative to professionalise manual drilling from 2009
The United Kingdom's Unlocking the Potential of Groundwater for the Poor (UPGro) since 2013