Why You Should Plan for UXO Risk Mitigation from the Start of a New Build Project
When planning a new housing development, it’s easy to focus on the visible: land acquisition, architectural design, planning permissions, and early groundwork. But beneath the surface there may be hidden risks that could have serious consequences for safety, costs, and project timelines.
Unexploded ordnance (UXO) is one such risk. While it may not be top of mind in the early stages of a new build, overlooking it can lead to costly delays, unforeseen safety concerns, and, in some cases, forced site closures.
At Brimstone UXO, we work with developers and construction professionals across the UK to help them assess and mitigate UXO risks, ideally before any shovels hit the ground.
Here’s why UXO mitigation should be part of your new build planning process from day one.
UXO Risks in the UK: More Common Than You Might Think
Due to extensive bombing during the Second World War, as well as decades of military activity, manufacturing, and munitions testing, large areas of the UK remain at risk from unexploded ordnance. This includes not only heavily bombed urban centres and strategic sites, but also rural areas that hosted airfields, training ranges, or storage facilities.
Although clearance operations were carried out after the war, efforts were limited by the technology of the time. These operations were also primarily focused on cities or former military grounds, meaning some ordnance was inevitably missed. Many of these items remain buried and undetected, only coming to light when ground is disturbed for construction.
In some instances, former high-risk areas have since been developed for housing or infrastructure. However, redevelopment doesn’t automatically eliminate the UXO risk, especially if risk mitigation was not properly addressed at the time. UXO can lie dormant for decades until construction activity uncovers it.
Early Mitigation Means Fewer Surprises (and Lower Costs)
Identifying and addressing UXO risks from the start allows you to make informed decisions about site planning and project timelines. If a site is found to have a low risk, this can be formally recorded and signed off, helping to reassure stakeholders and keep projects moving along.
If a moderate or high risk is identified, it gives you time to put the right mitigation strategies in place, such as intrusive surveys or watching briefs, without having to pause works or bring in emergency resources later on.
In contrast, reacting to UXO risks late in the new build process, or ignoring them altogether, often leads to unplanned stoppages and rushed mitigation, particularly when works are already underway. This reactive approach is typically more expensive and disruptive. Key consequences can include:
- Project delays: Work can be brought to a standstill when a suspicious object is uncovered. Investigations and any required mitigation measures may take days, or even weeks, creating significant delays and knock-on impacts across the wider build schedule.
- Increased costs: Expenses can quickly mount, from urgent assessments and removals to extended project timelines and potential evacuations. These unplanned costs can severely impact your budget.
- Safety hazards: Above all, UXO poses a serious threat to life. If disturbed, it can detonate, causing serious injury, fatalities, or damage to equipment and property. Ignoring UXO risks compromises the safety of your team and the surrounding community.
- Reputational risks: A UXO incident can attract national media coverage and damage your reputation. This may affect relationships with investors, partners, and future clients.
- Rushed mitigation: A last-minute effort to secure clearance may result in rushed procedures. While Brimstone UXO is always responsive and professional, we strongly believe UXO mitigation deserves thorough planning and careful execution. After all, these are explosive devices we’re dealing with!
Legal and Regulatory Requirements
While there isn’t any legislation in the UK defining the steps you must take to check for UXO before construction work begins, there are legal requirements to ensure the health and safety of your employees under the Health and Safety at Work Act 1974 and CDM2015.
There is also CIRIA C681 – the industry guide aimed at the construction industry outlining the steps you should take to manage the risks associated with UXO.
The guide was published in 2009 and was developed in response to a rise in UXO finds on UK construction sites. It offers practical advice for developers, contractors, and consultants on how to assess and manage UXO risk in a way that supports legal compliance.
Failing to comply with these regulations can lead to fines, legal action, and the shutdown of construction projects. Companies found to be in violation of health and safety laws due to UXO-related incidents can face legal repercussions, not only from regulators but also from injured workers or impacted communities.
UXO Risks and the New Build Agenda
With the UK government’s pledge to build 1.5 million new homes over the next five years, much of the focus is on maximising land availability, particularly in urban areas and on previously developed land.
While this is a positive move for housing supply, it also means more construction on sites with complex histories.
Former industrial estates, docklands, airfields, and even city centre plots can all have hidden UXO risks that aren’t obvious from a surface-level site visit. Without a proper assessment, developers risk sleepwalking into delays, cost overruns, or worse.
In an environment where tight timelines and margins are the norm, factoring in UXO risk mitigation early is not just best practice – it’s a necessity.
A Smarter Approach to Site Safety
Planning for UXO risks from the beginning doesn’t have to slow your project down. In fact, it can help keep it on track.
At Brimstone UXO, our risk mitigation process starts with a UXO Risk Assessment, tailored to your site’s location, history, and development plans. If further investigation is needed, we’ll advise on the most appropriate and cost-effective next steps, whether that’s a UXO survey or on-site support during groundworks.
This proactive approach allows you to factor UXO risks into your project plan from the start, avoiding the scramble to resolve issues when works are already underway.
The Bottom Line
For new build developers, the pressure to deliver is higher than ever. Margins are tight, deadlines are critical, and any disruption can have knock-on effects across the supply chain.
By planning for UXO risk mitigation early, you reduce uncertainty, manage risk more effectively, and create a safer environment for everyone involved, from groundworkers to future residents.
If you’re planning a new build development and want to ensure the UXO risk is properly managed, get in touch with Brimstone UXO – we’ll help you move forward with confidence, ensuring safety every step of the way.
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