SMARTWATER: low-cost, open-source portable water autosampler for environmental monitoring

Water sampling is essential for assessing the quality of rural and urban water systems. As part of the NERC-NSFGEO SMARTWATER project we aim to diagnose pollution “hot spots” and “hot moments” within watersheds defined as locations and times of pollution transport. To understand and diagnose pollutant dynamics we are forming a smart monitoring network consisting of offline and online sensors, low-cost proxy sensor measurements, and event-based sample collection using autosamplers.

To address existing autosampler constraints, we have developed a smart online autosampler that can be triggered either by a float switch or remotely through a LoRa network. The system is optimised for low-power operation using 12V electronics, light and smaller lithium-based batteries, power optimised Arduino controller, LoRa shield, commercial solenoid values and relays. Laboratory testing has validated the system operation and effective flushing of water between sampling bottle fills. Field deployment along our urban observatory, the Birmingham Urban River Observatory, a UNESCO Intergovernmental Hydrological Programme site, demonstrated performance comparable to standard systems.

This open-source design enables scalable, cost-effective monitoring of river water quality, facilitating improved spatial and temporal assessment across multiple catchments. SMARTWATER: https://www.smart-water.org.uk/