The challenge
This project in the north of Blackpool was required to reduce the number of discharges into the sea outfall. United Utilities needed to improve the quality of the bathing waters which, at the time, did not meet the Environment Agency’s standards.
Anchorsholme Park lies on Lancashire’s Fylde Coast, four miles north of Blackpool Tower. For many years, locals and visitors have largely avoided bathing in the Irish Sea given its reputation for poor water quality. The objective of the project for client United Utilities, was therefore to ‘move towards three spills per bathing season’ and meet the National Environment Programme (NEP) driver.
A huge new underground stormwater storage tank, pumping station and 3.7km long sea outfall would deliver on these goals.
What we did
First, we designed and constructed a large underground stormwater storage tank (circa 30m deep and 30m wide) capable of holding approximately 12,000m3 of stormwater. We altered its design by adding a ‘cutting shoe,’ which allowed the structure to sink, as the earth was excavated and concrete was placed on top of the tank walls. This saved three weeks on the programme.
We then returned to Anchorsholme to design and construct the adjacent underground pumping station connections to the existing long sea outfall, including an underground pumping station, stormwater chamber, weir chamber and MEICA installations.
The component parts of the overall facility were concealed underground, above which we constructed tennis courts, an outdoor football area, netball and basketball courts, a café and an outdoor amphitheatre.
We carefully managed the interface with the long sea outfall contractor.
We streamlined our programme to deliver three phases to operational status, by the required Ofwat regulatory dates, with the pumping station operational a month early. We achieved these deadlines whilst working within challenging marine and underground environments and a very constrained site footprint.
Extensive value engineering realised TOTEX savings required to meet the regulatory dates and budgetary constraints. For example, we rationalised the pumping station footprint and identified innovative techniques to reduce cost and time. Our joint probability and risk-based approach to specifying mechanical equipment enabled adoption of a cast in situ caisson solution that saved £2m+.
Programming the above ground works within a constrained footprint presented a challenge with 80 people, from eight organisations, working within the footprint at peak. Once the building substructure was sufficiently completed, sections were released for the subcontractor M&E installation. This required close collaborative working with multiple installations running concurrently. We held weekly collaborative planning meetings to organise working around each other effectively, minimising programme impacts without compromising on health and safety.
Project successes
We have succeeded in creating facilities that will hold up to five Olympic-sized swimming pools of stormwater, preventing it from entering the local bathing waters untreated. The scheme has also allowed a welcome development to the landscape, which is now thoroughly enjoyed by both locals and visitors alike. This project won the ‘Lancashire Project of the Year’ award, at the Northwest Regional Construction awards.
We delivered this scheme in harmony with the surrounding community. Our full-time Customer Experience Manager engaged with 231 residents through door-to-door knocking. She returned to those most affected on a weekly basis. She encouraged the local community to visit our site-based customer drop-in centre and ensured any concerns were dealt with immediately by the site team. As a result, we received over 20 WOW customer service award nominations.
We also won ‘Utility Project of the Year 2020’ at the British Construction Industry Awards.