Tumbledown Terrace - Ferniehill, Gilmerton

In early November 2000, a resident living in Ferniehill Terrace noticed a crack had appeared in her ceiling. By the next day, more hairline cracks had appeared. Council workers were notified and started to monitor the situation. By the following week, as property movement continued to be detected in the street, it was decided that residents needed to be moved out for their safety. Later in the month, there was a significant ground movement which affected more homes.

It was known that the houses had been built on the site of former limestone mines. When the mines had been excavated decades earlier, the miners dug out horizontally creating caverns, leaving pillars of unmined limestone at intervals supporting the mine workings. The mines had been worked into the 1940s and records showed that there had been a cast limestone quarry near the houses to depths of between 15m and 20m. The 3m deep galleries spanned 9 to 10 metres between pillars.

The Council worked with engineer partners, ARUP Scotland to investigate the cause and scale of the problem. ARUP drilled test holes to assess the size of underground spaces, enabling predictions of where any other buildings may collapse. They also used an underwater cavity sonar device to find out how much of the ground had been removed during mining and the size of the pillars that remained.

The investigations undertaken by ARUP led them to conclude that the buildings in Ferniehill collapsed because of an underground pillar eroding. This put stress on surrounding pillars and they in turn, collapsed too. Erosion of the limestone pillars was caused by the cavities becoming with flooded with groundwater over time.

During November and December 2000, 33 houses had to be demolished at Ferniehill. Other areas built on top of limestone mines were identified as being at similar risk of subsidence. Homes and flats at nearby Moredun Park, Hyvots and Gilmerton Dykes Road were also affected. The collapse of houses at Ferniehill was the first instance of its kind in Scotland.

In 2022, Robert Carroll at Gilmerton Library undertook a local history project to record residents’ memories of the incident and how it affected local people. We’re grateful to Ann Sinclair for sharing photos and her recollections of the time in a recorded interview. This exhibition brings together those photos, Council documents distributed to residents and her audio recording to give a personal account of the news which shocked her neighbourhood.

Sources:
Various Edinburgh Evening News articles from Edinburgh and Scottish Collection press cuttings collection
Living on Air from NewCivilEngineer.com.