Climate change and drinking water from Scottish peatlands: Where increasing DOC is an issue?

Area of Science:

• Environmental Science
• Climate Change Impacts
• Water Resource Management

Background:

• Rising dissolved organic carbon (DOC) levels in Northern Hemisphere water bodies are a growing concern, potentially exacerbated by climate change.
• Drinking water reservoirs in peatland catchments face increased challenges due to high existing DOC levels.
• Scotland's climate projections indicate warmer temperatures and altered rainfall, threatening peatland stability.

Purpose of the Study:

• To estimate the risk to Scotland's drinking water provision from climate change-induced peatland loss and subsequent DOC increase.
• To identify catchments most vulnerable to elevated DOC concentrations in public drinking water reservoirs.
• To inform targeted water treatment strategies and peatland restoration efforts.

Main Methods:

• Utilized two bioclimatic envelope models (Blanket bog Tree model, Lindsay Modified model) to project blanket bog distribution in Scotland by the 2050s.
• Quantified the at-risk peatland area and estimated potential annual carbon loss to DOC in affected catchments.
• Calculated potential increases in DOC concentration ([DOC]) within drinking water reservoirs.

Main Results:

• Significant variability in climate change impacts on DOC levels across different catchments was observed.
• Some catchments are projected to experience substantial seasonal increases in [DOC] due to peatland degradation.
• A few catchments were identified as being largely unaffected by the projected changes.

Conclusions:

• Frequent monitoring of DOC levels is crucial for reservoirs in vulnerable catchments.
• Peatland restoration is indicated as a potentially effective strategy to mitigate DOC increases and ensure safe drinking water.
• Proactive measures are necessary to address the risks posed by climate change to water quality.