Water & Wastewater Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/1131895
www.wwtonline.co.uk | WWT | XXXX 20XX | 21 The area is also an archaeological hot- spot, having played host to invading Ro- mans, Vikings and Normans, so the team engaged University College London ASE (Archaeology South-East) at the outset. "It seems like everyone throughout history passed through the fields where we were working," Yates adds. "We were digging in a highly sensitive site with the potential for significant archaeological finds throughout the 800m replacement." In common with many other projects in the region, Southern Water also had to take into account the ecological sensitiv- ity of the area. Due to the risk of groundwater con- tamination, the Environment Agency had designated it as an SPZ2 outer protection zone, but the primary ecological issue was that the sinkhole itself was in an area of heavily built-up scrubland. "We found bank voles, lizards and all sorts of things that had to be moved prior to work," Yates says. To tackle the project, Southern Water adopted a new approach. "We became aware of the pipe failure on 17 January and kicked into gear imme- diately with our emergency response, but we decided to do it differently this time," Perkins says. "It was a scheme that might sit between departments – it was an ops reactive repair, but it was very large and wasn't in our capital programme of works. "So, for the first time, we decided to run it with a collective approach, bring- ing together Jon and the engineering construction side of the business with my ops speed-of-repair approach, and together we created the project team with our delivery partners, who were going to do most of the actual repair work." www.wwtonline.co.uk | WWT | JULY 2018 | 21 For Yates, the new approach meant a significant change of tack. "Normally in my world I have more time to consider the things that might af- fect a project, like the UXO, the topogra- phy and history of the ground," he says. "We get a project, we go to our enabling team, they internally look at the risks associated with the area and, if there's a UXO presence, we then request a formal desktop study, and that would kick off potentially a three-month period of work. On this project, to enable us to be off the airport for the end of March, we were carrying that out in three weeks." To meet their schedule without taking risks, the team had to not only increase speed but also reconfigure many of their working processes. For example, the UXO specialists be- gan with desktop studies as normal but, Le : The archaeological survey found evidence of pottery, an ancient ditch system and fire pits. Right: A er establishing that the ground was safe, the team was able to survey the sewer to determine what work would be required