- 23rd July 2020
- Posted by: Miranda Pont
- Category: Blog
We work at the forefront of flood risk management and delivering Flood Risk Assessments to a range of industries. This week David Bassett, Director, looks at our water resource and flood risk assessment work for the distilling industry in Scotland.
One of Scotland’s specialty industries is the production of finest malt whisky and the market has been growing around the world for this luxury item. Exports are close to £5 billion and support a thriving and growing industry. Many of the existing distilleries are in established locations close to the water that they need for the whisky and cooling process.
Following heavy snowfall in 2010 there were a number of old bonding warehouses that needed repair, and also required expansion to meet demand. These sites were close to rivers and often required flood risk assessments. We were involved with a number of these projects, and we were subsequently asked to assist with licensing of water abstractions and the sustainable harvest of water.
How have we been involved?
Since then we have worked with the largest malt whisky distillery, as well as a number of new distilleries to find and secure water. Many of the distilleries are located on the banks of some of our best rivers, where tourism and salmon are both hugely important to the economy. These rivers are often dynamic gravel bed rivers with plenty of clean water. They are also home to salmon and often to the fresh-water pearl mussel and the rare but slightly less glamorous lamprey.
We have worked to determine where water can be safely abstracted and returned to the environment, undertaking hydrological studies to check catchment capacity and reviewing the most appropriate abstraction technique.
Traditionally weirs have been used to divert water into lades or pipes to deliver water to distilleries. However these place barriers to fish passage, and the associated screens can be harmful to wildlife, high maintenance and difficult to maintain during high flows.
Like most industries, distillers are looking for low maintenance and reliable solutions. We have looked at using below bed abstractions to minimise the long-term intrusion, and abstract without causing risk to the fish, fry or eggs. Water is filtered through the natural bed and then piped by gravity through a wedge wire pipe before being pumped up to the distillery. The abstractions can have automated air flush and do not require screen cleaning like many of the abstraction from the river side.
To reduce the impact of abstractions we have returned discharges upstream or close to the discharge point. Where appropriate we have also reviewed and sourced water from boreholes or ground water, particularly for process water, which is for use in the bottle.
At some sites we have helped harvest water from particular springs to help sustain the story of the distillery. We have also assisted by monitoring flows to allow sustainable abstractions, and designed storage to help distilleries through the drier, usually summer months. Other abstractions have come from existing reservoirs and even a canal.
We have been lucky enough to work on sites across Speyside, Alness, Islay, Skye, Fife, Falkirk and the Borders.
We are now working with companies to help assess the impact of discharges on rivers as the water is taken at around 8 centigrade and returned much warmer. A recent survey on the river Fiddich found that some of the early stage salmon were larger than in control sites and this is probably associated with warmer water. More work on a larger scale is required to understand the impact on adult forms and future recruitment. We have worked with Trex Ecology and The Spey Fisheries board to undertake electro-fishing as part of the project.
What does the future hold?
This summer has been quite dry and it is likely that some water abstractions will be getting close to their license.
We have recently been asked to develop proposals for 3D modelling of discharges to understand how discharges mix and whether this could be used to assess any thermal barriers. More information on our CFD modelling can be found here.
Going forward we are looking at the impact of climate change on particular sites and hope to be working on how we can improve water recycling, top up aquifers or use rain water harvesting to supplement supplies during seasonally dry periods.
Want to know more?
More information about a range of the distilling sites we have worked on can be found here.