With rain forecast for Scotland this weekend, parts of the country could see the unusual situation of surface water flooding while being in an area of significant water scarcity.
The current water scarcity situation has been built up over a long period of time. Over the last six months we have ‘missed out’ around a months’ worth of rainfall compared to a normal average year. This missing rainfall would have topped up reservoirs, raised groundwater levels and provided moisture in the soils.
A short period of heavy rainfall is not sufficient to make up this shortfall of rainfall and much of it may quickly run off the dry soils without soaking in. This is why it is possible to have heavy rain and even the possibility of some surface water flooding at the same time as we are warning about water scarcity.
Where will be affected by flooding?
Martin Marsden, SEPA Head of Environmental Quality, said:
“The current period of warm, dry weather over Scotland will take a break this weekend, with thunderstorms expected to affect north eastern parts of Scotland late Friday night, and showers and thundery downpours continuing until Saturday afternoon. This brings a risk of surface water flooding on Saturday, with the greatest risk in Angus, Aberdeenshire, Moray, Caithness and Sutherland. However downpours may occur along much of eastern Scotland from Scottish Borders northwards to the Orkney Islands.
“Further rainfall is also forecast over wider areas, from Southern uplands to the Highlands on Sunday, with the potential for localised flooding.
“The unpredictable nature of the weather front makes it difficult to predict where the heaviest showers will fall, therefore it’s important to be mindful of conditions if travelling over the weekend.”
Water scarcity and fish
“The prolonged period of dry weather that has led to water scarcity across the country has put a lot of pressure on rivers, which are running exceptionally low and experiencing high water temperatures. We have seen impacts on wildlife across the country over the last few weeks, including dead fish in the River Stinchar in Ayrshire and the River Ericht in Perthshire and deaths of the rare freshwater pearl mussels. This week we have also started receiving reports of dead fish in the River Clyde by the tidal weir, which we are investigating.
“Heavy rain showers, such as those forecast this weekend, following the prolonged period of dry weather will wash pollutants that have been accumulating on roads and pavements and in drains into watercourses. This first flush of pollutants, particularly into rivers that are still low, could lead to further fish kills.”
SEPA's 24 hour Pollution Hotline can be contacted by telephone on 0800 80 70 60 or you can use the online reporting form at www.sepa.org.uk/report
The lastest flood updates are always available on SEPA's website.