After months of dry weather across the UK, heavy rain can seem like exactly what homes and businesses need. However, sudden downpours do not resolve water shortages caused by prolonged periods of low rainfall.
Environment Agency data for the week ending 8th September 2026 showed reservoir storage across England at 56.9%, almost 20% below the long term average for the time of year. Twelve reservoirs or reservoir groups were less than half full, while 10 Environment Agency areas remained in drought status.
For the construction industry, this highlights the need to consider water resilience beyond managing heavy rainfall, surface runoff, and drainage. As climate patterns become less predictable, developments need to be designed to cope with both intense rainfall and periods of water scarcity.
Danny Locke, Operations Director at ByWater Services, said: “The mistake is treating water as something to deal with once a site is operational. By the time a development is built, some of the biggest opportunities to capture, reuse, store, and manage water have already been designed in, or designed out”
This means looking beyond reliance on mains supply or simply finding the quickest way to move excess water away from a site.
At design stage, developers can consider how much water a development will require, where non potable water could be used, whether rainfall can be captured and reused, and whether wash water or process water can be treated and recirculated.
They can also assess whether there is sufficient space for storage and treatment infrastructure, and how these systems will be accessed and maintained once the site is operational. Integrating these measures during design is significantly easier than adding them after a development has been built.
Water resilience should therefore sit alongside considerations such as energy efficiency, carbon reduction, and biodiversity. Developments are expected to operate for decades, so the way they consume, store, and discharge water requires the same long term thinking.
Locke added: “Water resilience does not necessarily mean adding more infrastructure. It starts with understanding how water will move through the site, where potable water is genuinely needed and where opportunities exist to capture or reuse water instead.”
Managing the whole water cycle
Historically, much of the focus on water in developments has been on moving excess rainfall away from buildings as efficiently as possible. That remains important, but resilience requires a broader approach.
Rather than treating rainfall or wastewater purely as something to remove, developments can consider where water can be captured, stored, treated, and safely reused. This can reduce demand for mains potable water while making better use of supplies already available on site.
Rainwater harvesting, on site storage, sustainable drainage, and water reclamation can all form part of this approach. ByWater designs bespoke rainwater harvesting systems to collect, filter, and store water for uses including irrigation, wash down, process applications, and other non potable requirements.
The value lies not simply in installing individual technologies, but in understanding how they work together as part of the site’s wider water cycle.
Lessons from Qatar
ByWater has already seen this approach work in practice. At a manufacturing facility in Qatar, the company designed a water reclamation system to reduce reliance on freshwater and improve the management of wastewater from equipment cleaning.
The system achieved 97% water recycling efficiency, demonstrating the potential benefits of considering treatment and reuse as part of wider site operations.
The context is different from the UK, but the principle is the same: water resilience works best when it is designed into a site from the start.
Planning for future water risks
Water resilience is not only an environmental issue. It can also affect operating costs, infrastructure requirements, and how easily a site can adapt in the future.
Reducing mains water demand, reusing water where appropriate, and planning storage or treatment infrastructure early can reduce pressure on a development later.
Not every development will need the same solution. The key is understanding a site’s water risks early enough for the design to respond.
There are three main priorities
- Consider water earlier. Make water management part of the design process rather than addressing it once the site is operational.
- Plan for both extremes. Developments need to cope with heavy rainfall as well as periods of water scarcity.
- Focus on the outcome. The aim should be to reduce unnecessary mains water use and make better use of water already available on site.
Heavy rain is a reminder, not a solution
Heavy rain does not mean longer term water pressures have disappeared.
For the construction industry, water increasingly needs to be treated in the same way as energy use or carbon reduction: something that is planned for from the beginning.
Locke concluded: “The most resilient developments will be the ones that understand their water needs from the start and design around them.”
Long term water resilience therefore needs to be built into developments from the outset, rather than addressed after construction is complete.