Active-distributed temperature sensing dataset beneath a braided river

Alice J Sai Louie; Leanne K Morgan; Eddie W Banks; David Dempsey; Scott Wilson

doi:10.1016/j.dib.2023.109756

Active-distributed temperature sensing dataset beneath a braided river

Data Brief. 2023 Nov 4:51:109756. doi: 10.1016/j.dib.2023.109756. eCollection 2023 Dec.

Authors

Alice J Sai Louie¹, Leanne K Morgan¹, Eddie W Banks², David Dempsey³, Scott Wilson⁴

Affiliations

¹ Waterways Centre for Freshwater Management, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
² National Centre for Groundwater Research and Training and College of Science and Engineering, Flinders University, GPO Box 2100, Adelaide, SA 5001, Australia.
³ Department of Civil and Natural Resources Engineering, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
⁴ Lincoln Agritech Limited, PO Box 69 133, Lincoln, Christchurch 7640, New Zealand.

Abstract

Braided rivers play a significant role in replenishing groundwater, but our understanding of how these recharge rates fluctuate over time remains limited. Traditional techniques for gauging groundwater recharge are ineffective for studying complex braided river systems due to their insufficient spatiotemporal resolution. To address this gap, active-distributed temperature sensing (A-DTS) was used. This method combines fiber optic temperature measurements with an active heat source, enabling quantification of groundwater fluxes. In this study, twelve consecutive A-DTS surveys were conducted on a 100 m long hybrid fiber optic cable to a depth of 5 m beneath the Waikirikiri Selwyn River. This experiment was conducted during a period of relatively stable river stage and flow, highlighting the effectiveness of using A-DTS to measure temporal changes in groundwater recharge.

Keywords: Alluvial aquifer; Fiber optics; Groundwater recharge; Heat as a tracer; River.