Fig. 3: River validation of the WaterScope system.
From: Expanding access to water quality monitoring with the open-source WaterScope testing platform
Tests were performed biweekly throughout 2022 on the River Cam (52°10′17“N, 0°5′55“E) with 2 to 5 samples each for WaterScope (WS - red), CCA (blue, ISO 9308-1) and Colilert-18 (orange, ISO 9308-2) approaches. a Variation in mean EC counts throughout the year, with semi-transparent fills showing standard deviation. b Scatterplots of WS counts vs reference method counts, with linear trendlines fitted. c Correlation matrix showing Spearman rank for different methods. d Mean-difference plots comparing WS and reference methods, right-panel shows mean value (circle) and 95% confidence interval (error bars) with kernel density approximation (violin plot) for each reference. Note that the Most Probable Number (MPN) approach was used with Colilert-18.
