Event Based Surface Water Monitoring
CWD staff members conduct storm event sampling at primary stream monitoring stations, Fresh Pond Reservation, and at major pipes and other discharge locations. The goal of the storm event sampling is to collect samples of the first flush of runoff from storms producing 0.5 inches or more of rain after a period of at least 3 days of dry weather.
Stormwater samples are analyzed for color, bacteria, alkalinity, total suspended solids, and concentrations of major ions, nutrients, and selected metals. Stormwater sample results are compared to baseline levels from routine, dry-weather monitoring in order to assess the effects of storms on introducing sediment and associated constituent loads to the reservoir.