Patterns and Drivers of Conductivity and pH in an Urban Stream

How do impervious cover and the Vassar Lake impoundment affect specific conductance and pH in the Fonteynkill?

Winter specific conductance increased upon the introduction of de-icing salt. Peaks in salinity are higher at the TH Path sonde site, upstream of Vassar Lake. Downstream of Vassar Lake, SpCond increases are of lesser magnitude but longer duration. Outside of the winter salting season, rain events lower SpCond–briefly at the TH site, and for a longer period of time at the sites below Vassar Lake.

Vassar Lake also affects temperature: the RC and SG sites below the impoundment experienced more extreme temperatures–colder in winter and warmer in summer–due to the retention of water in the pond (residence time is about 1-2 days). The impoundment also elevates pH due to biotic activity.

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