Fig. 3.

Ratio of log(cases per 100,000) over log(wastewater concentration) at sewersheds D1 (n = 262), D2 (n = 244), K (n = 172), L (n = 121), and M (n = 131), for three surges (separated by vertical gray lines). Smoothed lines were generated with lowess (alpha = 0.05), and the dashed line represents the median ratio across all 5 sewersheds (0.55). For each sewershed shown, case data masking was below 5 % of all data points. Two outliers were removed at sewershed M for visualization.