Drop in water level of Loch remains a mystery
● Archaeologists investigate the effect of the loss of water on crannogs
Startling pictures that show the dramatic drop in water in a Highland loch have emerged as experts confirm it reached its lowest level in at least 750 years this year.
Loch Vaa, near Aviemore, Scottish Highlands, lost a sudden amount of water between September 2018 and May – dropping 1.4 metres in depth.
Archaeologists were asked to investigate the effect of the loss of water on the loch’s crannog, an elevated ancient settlement made of wood.
They found that some of the birch wood originally made to create the structure originated as far back as the 13th century.
Some of the timber below the waterline is so well preserved that there are still axe marks from when the wood was cut down centuries ago.
Dr Michael Stratigos, a research assistant at the Scottish Universities Environmental Research Centre (SUERC), said: “It was effectively an opportunity to check whether the low water levels were affecting archaeology.
“Crannogs typically contain well preserved timbers but they can rot if they dry out.
“That’s the fantastic nature of Scottish lochs. They’re cold, dark and there’s no oxygen below the sediment level, so there’s no organic decay taking place.
“The water level certainly hasn’t been any lower than when the timber was built into the crannog, based on data from carbon dating, which suggests around 1260.
“The water hadn’t dropped below that position in 750 years.”
Since May the water levels have returned to normal levels, but fishing on the loch was hugely impacted last autumn and this year.
Loch Vaa is a Site of Special Scientific Interest (SSSI), which means fishing by the banks is prohibited and boats must be used instead.
As a result of the drastically low water line, the fishing season this year was cancelled.
Brian O’donnell, 61, helps to manage fishing activity on the loch and said the loss of water is a “total mystery”.
He said: “It seemed to coincide with motorway drilling for the A9, but to lose 55 million gallons of water is unbelievable.
“There’s concerns but it came back up in the past few months. It’s a total mystery where the water went.”