Dallas Flood Alleviation Scheme, April - June 2017
Dallas – Summary
The Dallas Flood Alleviation Scheme was completed on 16th August 2017. This now provides a level of flood defence to the village of Dallas to approximately a 1 in 1000 year event.
1. Dallas Flood Alleviation Scheme - Complete
The project was successful in causing minimal disruption to the local residents and environment. There were some delays to the project due to bad weather and construction issues, however the main delay resulted from a flood event that occurred on 7th June 2017. At the time of the flood the embankment was in its final stages of construction, which included the laying of the clay bentonite membrane and the final topsoil layer. The majority of embankment sections that were exposed to the worst of the flood waters had already been completed so only suffered minor surface damage.
2. June 2017 flood damage
Only a 10 metre section of the clay liner, which was in the process of being laid had to be replaced due to damage. The flood acted as an excellent test to the integrity of the embankment, which remained intact throughout. The flood event in June also allowed us to record how the water reacted with the embankment. The issue of water flowing around the East end of the embankment and ponding on its dry-side was noticed. This was caused by debris and mud building up on the field boundary fences and stopping water from flowing out.
3. Additional bund - East side
To prevent water building up on the dry-side of the embankment an additional bund was constructed at the north east end between the boundary fence and the embankment (see above photo).
The scheme will be maintained by Moray Council, with grass cutting throughout the season to keep the area tidy and neat. The area will also be regularly inspected to ensure the scheme is fully operational and to repair any damage. The scheme will also be checked by an Engineer after any flood events in order to repair any damage that may have occurred.
4. School visit
As part of our Dallas community engagement, representatives from Moray Council’s Engineering Consultancy gave pupils from Dallas primary School a tour of the scheme in September 2017 explaining the principles behind how the embankment works and how the flooding occurs. The visit seemed to be a success with the pupils who took a great interest in what was going on in their village.