Welsh Water was up against a pressing deadline in July 1997 when Coslett was dropped in to lead the £45M project.
While the Urban Wastewater Directive required effective sewage treatment to ensure Blue Flag bathing water quality at three beaches in Llandudno and Colwyn Bay by December 2000, the Environment Agency wanted the scheme running by May 1999.
This meant Coslett had to manage design and construction of the project in only 18 months, allowing four months to test and commission before the bathing season began.
Existing outfalls had to be intercepted to pump sewage back to a new centralised treatment works. Treated effluent could then be transferred to a new 1.8km long sea outfall at Penrhyn Bay. In all there were 14 new and extended pumping stations, 20km of rising mains, six tunnelled road and rail crossings and 10,000m3 of storm overflow storage tanks.
'It was clear to me from the outset that to meet the programme it was necessary to adopt a strategy which allowed for the mobilisation of civil contractors at outline design stage and for the development of detailed design to take place in parallel with construction,' says Coslett.
Contracting expertise was also harnessed in the partnered approach to the 10 separate civils contracts and 20 M&E contractors and suppliers.