The effect of varied dam release mechanisms and storage volume on downstream river thermal regimes

Laura E. Michie, James N. Hitchcock, Jason D. Thiem, Craig A. Boys, Simon M. Mitrovic

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

Temperature plays an essential role in the ecology and biology of aquatic ecosystems. The use of dams to store and subsequently re-regulate river flows can have a negative impact on the natural thermal regime of rivers, causing thermal pollution of downstream river ecosystems. Autonomous thermal loggers were used to measure temperature changes downstream of a large dam on the Macquarie River, in Australia's Murray-Darling Basin to quantify the effect of release mechanisms and dam storage volume on the downstream thermal regime. The magnitude of thermal pollution in the downstream river was affected by different release mechanisms, including bottom-level outlet releases, a thermal curtain (which draws water from above the hypolimnion), and spill-way release. Dam storage volume was linked to the magnitude of thermal pollution downstream; high storage volumes were related to severe thermal suppressions, with an approximate 10 °C difference occurring when water originated from high and low storage volumes. Downstream temperatures were 8 ̶ 10 °C higher when surface releases were used via a thermal curtain and the spillway to mitigate cold water pollution that frequently occurs in the river. Demonstrating the effectiveness of engineering and operational strategies used to mitigate cold water pollution highlight their potential contribution to fish conservation, threatened species recovery and environmental remediation of aquatic ecosystems.

Original languageEnglish
Article number125760
Pages (from-to)1-7
Number of pages7
JournalLimnologica
Volume81
DOIs
Publication statusPublished - Mar 2020
Externally publishedYes

Fingerprint Dive into the research topics of 'The effect of varied dam release mechanisms and storage volume on downstream river thermal regimes'. Together they form a unique fingerprint.

Cite this