There was an ongoing flooding issue on Balmore Road between St Kentigerns and Lambhill Cemeteries in Glasgow. Insufficient drainage within the large catchment area of the cemetery grounds was leading to flooding at the east entrances that, in extreme weather, causing runoff and flooding risks to the adjacent road.
Existing gullies within the section of road also drained to the nearby Possil Loch. However due to a rise in the water table, the outfalls had become submerged beneath the water level, limiting their effectiveness. The existing drainage system did not have enough capacity for the efficient and required drainage of the area.
We carried out investigations into the existing drainage system and it was apparent that several areas of the cemetery were draining toward the single outfall, which became overwhelmed during high rainfall.
Following our in-depth survey, we came up with a design for a new, large attenuation pond within the cemetery, which would capture the various systems that were leading to the outfall under Balmore Road.
The outfall channel on the opposite side of Balmore Road led to Possil Marsh, a site of Special Scientific Interest (SSI) of both flora and fauna within the city of Glasgow. We found that the existing channel had become choked over years by a build-up of bulrushes, preventing it from operating at full capacity. Prior to the works, temporary silt prevention measures were established close to the outfall into the marsh. The channel was then cleared and re-profiled to both increase capacity and make future maintenance easier.
Once the main drainage works were completed, the site was tidied and existing paths were reinstated in the cemetery.
Paths were also provided to the outfall channel to assist with future maintenance. A maintenance schedule was prepared and passed to the Client for implementation.
As a result of the work undertaken by Covanburn at the Lambhill Cemetery site, the area has improved drainage and increased capacity, making the area safer and decreasing the risk of flooding on the adjacent road. As well as fulfilling the brief, we also considered ease of future maintenance as part of the project, so any issues can be flagged up and dealt with as early as possible.