Stream temperature impacts of culverts and impervious areas

Water temperature in small, headwater streams may reveal much about stream health. Yet, our understanding of stream temperature and its driving factors is limited compared to other water quality parameters. In addition to natural factors, research suggests that watershed urbanization may impact a stream\u27s thermal regime. This research quantified culverts and impervious area\u27s stream temperature impacts across coastal NH streams using experimental data and a deterministic temperature model. Impervious areas were found to increase streams\u27 daily average temperatures, possibly accentuate storm temperature surges, but not diurnal temperature ranges. Road crossings were found to increase the variability of diurnal temperature ranges, daily average temperatures, and increase storm temperature surges. Culverts and parking lots\u27 thermal stormwater runoff impacts were observed during summer rainfall through high resolution temperature sensors. Modeling results showed that while solar radiation is the largest energy influx for most streams, it was not in reaches with dense canopy