Northern Gateway

Summary

In 2022, NHBC’s Land Quality Service (LQS) team was commissioned by Bellway Homes North West to secure a technical opinion on the acceptability of the proposals for the redevelopment of former farmland in Deeside, Wales into residential dwellings.

Bellway Homes were keen to avoid delays and expedite the warranty process using NHBC’s early engagement service. The LQS team were able to obtain valuable insight into the technical proposals for redevelopment, which included raising site levels by around 1.5m across the entire development for flood risk mitigation. 

The Challenge

The site is on former estuarine land that had been reclaimed over 200 years ago. Such sites often present geotechnical challenges due to the variable nature of the deposits which present potential settlement issues requiring careful technical considerations. In addition, former ponds also presented localised issues with organic deposits and potential contaminants of concern.

Solution

The benefits of NHBC Land Quality Certificate:

Land that has an NHBC Land Quality Certificate is reviewed geotechnically and geo-environmentally with compliance to NHBC Standards by the LQS Specialists. This process allowed the site to be assessed and de-risked as the LQS team will have thoroughly reviewed the desk study and ground investigation (Stage 1), earthwork and remediation strategies (Stage 2) and once completed the verification works (Stage 3)

This provides confidence in any site prior to registration with NHBC for our warranty and may add value and help support satisfying planning conditions.

Securing a Stage 1 to 3 Certificate of Land Quality:

LQS worked with Bellway Homes to issue the Stage 1 Certificate of Land Quality by reviewing available site information and data sets. This supported their subsequent development of a detailed Earthworks Strategy, addressing the need to raise site levels for flood protection and measures required to mitigate any potential for differential settlement.  

LQS during our review identified that there was a fundamental change in the strategy for the reuse of soils requiring a Materials Management Plan and Verification. This helped the development of a refined Remediation Strategy to support both the tendering stage and planning, this formed the Stage 2 Certificate of Land Quality. 

The LQS team have been commissioned to assist during the Stage 3 Verification process. This will include regular site visits and the production of further phased certificates for the development as it progresses.  LQS continued input will provide ongoing reassurance as Bellway Homes continue to build out the development from geotechnical or geo-environmental technical issues that could have caused delays during the construction process. 

Adrian Johnson, Technical Manager at Bellway Homes said

"The LQS team gave us the confidence to develop a technically complex site by providing unrivalled expertise. By guiding us through the process we were able to progress with the development successfully and potentially avoid any costly re-visits to works already undertaken."