UV lining team meets timeframe challenge to cure flooding

lanes-group-river-ness-lining-scottish-water

A sewer rehabilitation team from Lanes Group has met challenging working timeframes to complete a project that has reduced sewer flooding risks in a Scottish city.

The company was commissioned by Scottish Water to clean and line a combined sewer downstream of the Fisherman’s Car Park close to Inverness town centre, and alongside the River Ness.

The 300mm diameter clay pipe had been identified as being at high risk of contributing to localised flooding during heavy rainfall, inconveniencing locals and creating a pollution risk for the river.

A major challenge was to complete all work within tight daily timeframes to minimise their impact on nearby businesses and essential services. Lanes’ no-dig sewer rehabilitation expertise was key achieving this.

Ian Phillips, Project Manager for Scottish Water, said: “Specialist trenchless technology allowed the rehabilitation of this sewer to be completed quickly with minimal impact on the Ness Walk and Bishops Road areas.”

Jon Close, Senior Project Manager for Lanes Group’s Sewer Renovation Division, said: “The car park is close to the city centre and located near a hospital, a hospice and Inverness’s main theatre. It was important that these facilities, as well as commuters, were not inconvenienced, so the traffic management needed to allow us to work could only be in place between 6.30pm and 11.30pm.”

The main cause of the higher flood risk was tree roots infiltration into the sewer. Lanes’ drainage engineers used water jetting equipment to cut away the roots, guided by HD video footage recorded by a CCTV drainage survey team using a robotic camera.

CCTV survey footage was used by Scottish Water to assess the condition of the sewer and decide how much of its length needed to be lined to strengthen it and prevent further root ingress.

Over three more evenings, the Sewer Renovation Division team then installed three liners. Ultra violet (UV) cure in place pipe (CIPP) lining was selected because it suited the short working timeframe.

Jon Close said: “Once the UV liners were installed, they could be cured within one hour. We could then cut out lateral connections with the KA-TE cutter. This meant each pipe could be lined and reinstated within the five-hour window.”