Lortas Road, Basford

About the project

Danaher & Walsh was appointed to construct roads and sewers infrastructure for family-owned housebuilder Langridge Homes' development site on Lortas Road, in Basford, Nottingham.

Key details

Client
Langridge Homes
Project manager
BSP Consulting
Project value
£425k
Date
August - October 2017

Key aims and challenges

The site was previously home to Westbury Special School, which vacated the site after the building was severely damaged by fire. Langridge subsequently acquired the site from Nottingham City Council for a residential development.

Around 120m of adoptable highway was constructed, along with associated foul and storm drainage and manholes. 

This scheme, however, also features a unique flood alleviation system. Two huge banks of 3.4m wide x 2.5m high box section culverts, totalling 52m in length, were installed to act as a storm water attenuation reservoir. In total, they will provide approximately 450,000 litres of water storage.

Sheet piles were installed along the perimeter of the culvert pit, before the earth was excavated and set aside for re-use. The culverts were lifted into place using a large capacity mobile crane, for which a temporary crane bad had to be constructed. A custom pulley system was used to manoeuvre the precast units flush with one another.

This attenuation system is controlled via a 3m diameter manhole that was constructed, containing a flap valve inlet. The outlet is via a hydrobrake, which regulates the rate of outfall to the existing main sewer. The system is designed so that the culverts begin to fill in sequence after the manhole chamber meets capacity.