This workshop provides participants with background on off-the-shelf components that can serve as effective alternatives to expensive industry-standard water sensors, and benefit from the experience of the OPEnS Lab in building, calibrating, and fact-checking hand-made data loggers. This group contains workshop materials. This workshop was held virtually September 20th, 21st and 22nd, 2021. The group for the 2020 hosting of this workshop can be found here: https://www.hydroshare.org/group/163