Bidwell West Urban Extension

Civil Engineering and Road Construction

Client:
Bidwell Land Ownership Group
Engineer:
Hydrock, Matrix & WSP
Location:
Bidwell, Dunstable, Bedfordshire
Sector:
Infrastructure
Project Value:
£14 Million

Services:

Highways and Infrastructure Bulk Excavations

Project Scope

19,000m2 of new distributor roads
3km of onsite storm drainage
Four attenuation basins – 26,000m3
3km of onsite foul drainage
Foul pumping station and rising main
2km of a strategic offsite storm and foul
200m of 3mx3m RC Box Culverts
112,000 m3 of bulk earthworks
Two new offsite roundabouts
15km of new service mains
5,000 m2 of off-site Section 278 carriageway upgrade
Three substations including all superstructure works

Project Overview

In mid-2018 we was contracted by Bidwell Land Ownership Group, a consortium of local landowners, to deliver the strategic Infrastructure and section 278 works necessary to develop the 166 hectare site which will eventually accommodate nearly 2000 new homes.

The strategic Infrastructure and section 278 works commenced in the summer of 2018 with over 100,000m3 of bulk earthworks which proceed the installation of Phase 1, 2, 3 & 4 of the onsite works. These phases included over 6km of strategic storm and foul along with 19,000m2 of new carriageway. To facilitate the disposal of the foul sewage, a 7m deep in-situ pumping station was constructed, with an oversized wet-well and 300m of foul rising main connecting into the existing Houghton Regis trunk main.

The sustainably designed SUDS systems made best use of the existing watercourses that traversed the site. To tie-in the new drainage and road network, over 1,200 tonnes of pre-cast box culvert was installed along with 21 in-situ headwalls.

The Section 278 work was split into six phases, all of which involved removal and upgrade of the existing Thorn Road, whilst maintaining access for residents and developers. The installation of 2km of off-site drainage was carefully undertaken alongside a live HV cable – this work was meticulously planned to avoid incident.

Project Challenges

Just prior to commencing on site, a 3rd party developer and their incumbent contractor installed a new HV cable down the middle of Thorn Road for a new commercial development. Whilst the permanent design did not consider the new HV cable, we safely managed to plan and execute the Section 278 works without incident. Whilst completing the Section 278 highway works, full time access was maintained for existing residents and commercial vehicles along Thorn Road. Regular stakeholder meetings were necessary to ensure everyone was kept abreast of programming matters. A diversion of 3000m of overhead power cabling was co-ordinated to enable planned installation of the box culvert units.

Project Outcome

Meticulous planning, flexibility and innovative thinking were crucial to tackle this complex, evolving project. All services to be installed are on schedule and include; gas, electric, fibre, water and LV connections for the entire development, along with three substations – including all superstructure works. Temporary supplies of gas and LV were delivered where needed and the immediate availability of our specialist equipment prevented delays to the occupation dates of the first developer. The successful delivery on time and on schedule, and the ability to accommodate the challenging size and fluidity of the project resulted in us being awarded large contract extensions to assist with development of additional phases.