Experts are cautioning about the dangers of introducing invasive and non-native species when transferring large amounts of untreated water from lakes, reservoirs, and rivers.
Experts are cautioning about the dangers of introducing invasive and non-native species when transferring large amounts of untreated water from lakes, reservoirs, and rivers.
The growth of cities and agricultural needs have led to the frequent transportation of untreated water from lakes, reservoirs, and rivers over vast distances, reaching hundreds of miles through pipelines, tunnels, and canals. These raw water transfer projects are crucial for human use but pose a risk of transporting not only water but also wildlife, potentially spreading invasive and non-native species like zander fish and zebra mussels.
In a series of recent publications, researchers from Newcastle University and the University of Stirling emphasize that these invasive species can be transferred between often disconnected water bodies through intentional water movement and urge for immediate action.
In their findings published in the journal Management of Biological Invasions, the researchers stress the necessity of incorporating raw water transfers (RWTs) into cohesive monitoring and management strategies to align with national and international goals aimed at addressing invasive and non-native species. They suggest enhancing access to RWT information and fostering collaboration among stakeholders within the invasive non-native species management community.
The experts also advocate for greater awareness regarding the dangers associated with RWTs and the dissemination of invasive and non-native species, asserting these measures could significantly bolster efforts to preserve freshwater biodiversity in a rapidly evolving environment.
The approach to managing RWTs varies by country, often being overseen by private water companies or local and central governments. In England, most RWTs are operated by water companies, while the Environment Agency (EA) oversees several of these transfers.
The research team cites data indicating there are 110 surface water transfers in England and Wales that can move between 45 to 150 million liters each day, with approximately 43 of these crossing one or more catchment boundaries (39%).
Primary threat to biodiversity
Ava Waine, the lead author and a Ph.D. researcher at Newcastle University’s School of Natural and Environmental Sciences, stated: “Invasive species rank as one of the leading threats to biodiversity and the global economy. Raw water transfers facilitate the movement of these species across different ecosystems, yet researchers specializing in invasion ecology are only beginning to recognize the extent of their impact, while industries and regulators are not fully aware of the invasion risks or effective management strategies.”
“Recently, England, followed later by Scotland, became the first nations globally to mandate that raw water transfers be managed to prevent the spread of invasive species.”
“I have collaborated with Northumbrian Water to tackle these challenges. Our findings reveal that raw water transfers represent a largely unrecognized pathway for species to spread, indicating a need for modifications in national and international biodiversity policies to enhance global awareness of this issue and improve our chance of resolution.”
Dr. Zarah Pattison, co-author and Senior Lecturer in Plant Sciences at the University of Stirling, added: “This is an urgent call to action. We must take the threat of invasive and non-native species movement through raw water transfers seriously and allocate resources to study the extent of this risk across various species groups.”
This research builds upon a previously published study by the same team, which outlines how RWTs contribute to the spread of freshwater invasive non-native species globally. The researchers propose amendments to the corridor category in the Convention on Biological Diversity’s pathway classification framework to recognize RWTs as a distinct sub-category. They argue that this reclassification would enhance the understanding of RWTs, improve risk management, and inform policy development for effectively addressing the spread of invasive and non-native species.
