The heat is on: Predicting urban stream temperature responses to summer storms

Kelleher, Christa A.; Knapp, J. L. A.

The heat is on: Predicting urban stream temperature responses to summer storms

Abstract

Short-term increases in stream temperature in response to storm events have frequently been observed in urban areas, highlighting the need for improved understanding of the factors influencing urban stream temperature. Urban land cover complexity and infrastructure designed for rapid water routing to the sewer system create a direct link between storm events and water release processes, influencing urban stream temperature responses. This study aims to identify predictors of diverse stream temperature response patterns to summer storms. We analysed 403 storm events from six urban and semi-urban catchments along the US East Coast using dynamic time warping to identify archetype patterns of stream temperature responses. We further disentangled observed stream temperature increase patterns to reveal the drivers associated with ‘heat pulses’, which are characterized by a rapid but high-magnitude temperature
increase followed by a sharp temperature drop at the start of the hydrograph increase. Our results show that stream temperature patterns were event-specific and linked to pre-event conditions and rainfall–runoff characteristics, with the shape of the hydrograph and rainfall–runoff response identified as the most important determinators of the observed temperature response patterns. Ponded surface waters and storm drains, as well as cooler water from the shallow subsurface, were identified as potential sources contributing to temperature patterns. These findings have important implications for understanding urban hydrology and the contributions of different source zones in urban catchments. Specifically, our results suggest that stream temperature may serve as a cost-effective tracer providing information about urban water sources and pathways, thus aiding in the understanding of complex urban hydrology.

Title	The heat is on: Predicting urban stream temperature responses to summer storms
Creator	Kelleher, Christa A.
Creator	Knapp, J. L. A.
Publisher	Hydrological Processes
Academic Department	Civil & Environmental Engineering
Division	Engineering
Organization	Lafayette College
Date Issued	November 2023
Date Available	2023-12-08
Type	Article
Language	English
Keyword	heat pulse
	urban hydrology
	tracer
	rainfall–runoff characteristics
	storm events
	stream temperature
Bibliographic Citation	Knapp, J. L. A. and C. A Kelleher (2023 Nov) "The heat is on: Predicting urban stream temperature responses to summer storms." Hydrological Processes 37 (11): e15033.
Standard Identifier	Handle 10385/h989r477f
Standard Identifier	DOI 10.1002/hyp.15033
Permalink	http://hdl.handle.net/10385/h989r477f
Rights Statement	Creative Commons - Attribution, Non-Commercial
Rights Holders	Kelleher, Christa A.
Rights Holders	Knapp, J. L. A.