Delivering certainty through Modern Methods of Construction: leveraging our delivery model to provide capacity at speed for the Ministry of Justice

Located adjacent the existing Category B men’s prison at HMP Garth and existing Category C HMP Wymott, this new prison will provide 1,650 new places and a new workshop as part of the Alliance for New Prisons (A4NP). This programme of work forms the backbone to the MoJ’s 20k places programme, delivering nearly 6,500 new places.

Using in-house delivery to support efficient, safe delivery

The A4NP employs a platform-DfMA strategy for houseblock design across the programme. Lessons learnt from other prisons in the programme will be integrated into the HMP Garth design during the PCSA phase, while site-specific design is informed by survey data. The houseblock design incorporates precast columns, slabs, walls, facade panels and riser modules, all of which can be manufactured, delivered and installed by our specialist internal businesses.

Unlocking the site through careful planning and collaborative working

In order to release the main construction works, a complex sequence of activities must first be carried out to secure vacant possession of the site. These include S278 works and demolition of existing facilities currently located on the footprint of the new build. There are also significant ecological constraints, including a large maternity bat roost, relocation of barn owls, Great Crested Newt licencing and the presence of Himalayan Balsam. We re-employed the MoJ’s existing ecology consultant to retain their knowledge and speed the process, supporting them with our dedicated environmental manager.

We have engaged extensively with key stakeholders when considering the sequencing and methodology for these works. Our team regularly attends 420 meetings with the prison establishment team to review plans and provide forward visibility of activities.

De-risking below ground conditions through innovative thinking

The enabling works scope contains multiple service diversions, removals and new supplies. Our designated utilities manager has developed a master tracker for all utilities; this is supplemented by extensive survey work and digital modelling of the existing and new below ground services, allowing us to create a comprehensive picture of the local environment. It is vitally important that prison operations in the adjacent estate are not disrupted by these works. We have put in place safe methods of working and control systems to ensure continuity of service in the existing estate. For instance, we will be carrying out 1km of deep drainage utilising directional drilling techniques to avoid an open cut which would be more disruptive to prison and construction operations.