By Colin Wiles, housing consultant.

It’s official. According to the Met Office, February was the wettest ever recorded in England, Wales and Northern Ireland, with around 260% of rain falling above the 30-year trend. We averaged over 20cm of rain across the UK and some places had three to four times the average rainfall, with thousands being flooded in their homes. What a horrible experience that must be. We also had wind gusts of 93mph.

Yet just eight years ago we had one of the driest Februaries ever recorded, with around 62% of expected rainfall and predictions of drought. I wrote a blog about this at the time, calling for more storage of water during winter months.

This shows the reality of climate change. It’s either drought or deluge, with little in between. The weather is becoming more extreme. In terms of flooding, it seems to me that we need a major rethink about where and how we build our homes and how we retrofit them.

Recent reports suggest that one in 10 of all new homes in England since 2013 have been built on flood plains and that one in six homes are vulnerable to flooding. However, I don’t think there is anything intrinsically wrong in building on a flood plain. By their nature, flood plains only fulfil their purpose for relatively short periods of time, perhaps a couple of weeks each year.

Would it not be wasteful to allow such land to stand idle for most of the time when it can also contain a variety of other uses – leisure, wildlife reserves, car parking and even, dare I say it, home?

After all, if we limit our choices of land it’ll make it much harder to build the 300,000 homes a year that we need. But any homes that are built on flood plains will have to be adapted to cope with periodic floods and to allow the flood plain to do its natural work. That means homes where the living areas are raised above the most extreme flood level, perhaps on stilts or with multi-use basements that can cope with floods and where only inexpensive items are stored; or even floating homes that can rise and fall with the rising water.

Surfaces will need to be porous and sustainable drainage systems will need to be in place. This guide from the Mayor of London is a useful toolkit. Perhaps in future, roads could become waterways and cars that can also be converted into boats could be designed!

The BRE has been working on a flood resilient house, where electrics are raised and perishable materials like wood, plasterboard and chipboard are excluded from lower parts of the property. Apparently, this can withstand floods of two feet.

I think they need to be more ambitious and aim for a couple of meters. When Joseph Bazalgette designed the London sewers he worked out their capacity based on current forecasts and then doubled the dimensions. As a result, his sewers remained fit for purpose for over 150 years. We need to accelerate the amount of research and development in this area.

More importantly, we need to be much better at water management. The Dutch can teach us a thing or two as they are world experts at managing water. The Duke of Bedford brought in Sir Cornelius Vermuyden in 1630 to drain the Fens by building two great dykes that by-passed the Great Ouse and pushed water out to sea more quickly. His scheme is still going strong.

A flood plain is like a shallow bath that has water coming in at one end and out at the other. You can do two things to prevent it overflowing: stop or slow the water coming in, or speed up the water going out. Some people blame the floods on lack of dredging but I think it’d be
more effective to focus on the other end and slow the ingress of water from upland areas. To begin with, that means more balancing reservoirs and water storage tanks, allowing water to be released more slowly in times of drought. This would also help to preserve chalk streams and rivers like the Cam that are suffering from over-extraction by farmers.

But there also needs to be a bigger focus on the way upland areas are managed. I’m with George Monbiot on this. Grouse moors and sheep grazing appear to be key culprits. On grouse moors, drainage channels are scraped out and heather is burned to provide fresh plants for the birds. This means the moors don’t soak up water but shed it to the valleys more quickly. Returning these areas to traditional peat bogs would hold water back. Similarly, sheep trample all over turf-like upland areas and water races off more quickly.

Perhaps Brexit will provide an opportunity to rethink our agricultural policy and rewild some of these upland areas, planting trees to replace sheep grazing, for example. There’s also evidence that beavers can slow down water flows and improve wildlife populations.

Our weather in the future will be more extreme – hotter, wetter and windier, and this will have a dramatic impact upon the way properties are built and managed. This is why housing providers need to take it seriously, and why HQN has been labouring the issue.

Our climate change best practice group is a good starting point if you want to know how to respond. As a sector, we need to up our game and start thinking in a different way. The old methods are redundant.