Flash floods – can anything be done to mitigate their impact?

01 August 2019

Robert Frewen, Rural Surveyor with the CLA North team based near Richmond was directly impacted by the recent flash floods in Swaledale and Arkengarthdale. He lives on a hill between the two dales.

On Tuesday 30 July he was in the office near Richmond with the rest of the North team where it had been a mildly wet afternoon. Robert continues the story, “I left the office at five and went to a local supermarket to buy milk and something for supper as my wife was away in London. Then I set out for home – some fourteen miles from the office – only to find the road shut by the police who could tell me little other than that there was some flooding. As I know all the local back roads, I turned round and tried a narrow hill road that drops in to the village of Downholme, but where the road joins the main road below the village, it was shut again, this time being manned by a fire engine. So I returned to Richmond where there was good 4G and tried google to see if I could find out what was going on.

Limited luck there, other than ‘flash floods in Swaledale’ so I set out to come in from the A66 to the north over one of the high passes, the Stang. At over 1,700 feet, this is one of the highest tarmacked passes in the Pennines: the road was partially flooded but thanks to a big 4wd, I made it very slowly over the top and almost to the main road in Arkengarthdale only to find the bridge over the Arkle Beck under 8 feet of water. So another u-turn and the last throw of the dice before ringing a friend for a bed for the night. This meant driving further over the A66 into Cumbria to Brough and coming back on myself to the Tan Hill Inn and down Arkengarthdale from the north. Three and quarter hours later, I finally made it home, luckily to very little damage other some gravel lost from our drive.”

The same cannot be said for the villages of Reeth, Fremington and Grinton. Here the damage was massive: at least half a dozen cars had been written off in Fremington, the dry stone walls were all either in the road or in the fields, and large numbers of bales of silage had floated downstream. A bridge on the road between Grinton and Leyburn had been completely destroyed as had two sections of the main road to Richmond.

The clean-up and repair costs will run to millions. Much of this will be the responsibility of the local highways department, and another big loser will be flooded out householders, but they should be covered by insurance. A major local event “Ard Rock” has been cancelled: again they should have event cancellation insurance. The least likely to be covered by insurance are the farmers who face huge costs in moving soil and gravel from their fields as well as the stones from the walls all of which need to be rebuilt. The timing of this storm means that crop loss will not be severe

So can anything be done? In this case, it was a true flash flood, very localised and very quick. Between two pm and seven pm, 52mm of rain fell with a further 40mm by nine the next morning. So nearly four inches in less than 24 hours.

But Robert reckons that the reason his short drive survived at all is that he is disciplined about digging out two big offsets that take the water off the lane before it gets to his drive. Likewise the keepers on Reeth moor think that their annual maintenance prevented the extensive damage from being far worse. So while nothing can stop flash floods like this from causing problems, good annual maintenance certainly helps, and given that with global warming, dramatic weather might well become more frequent, it makes sense to start planning now.

It is interesting to note that the houses that flooded in Reeth have all been built since WWII – the older housing is higher up the hill, although some older houses in Fremington and Grinton did suffer including some houses “up the hill” but too close to Grinton Beck which burst its banks.

It is important that DEFRA reacts both with speed and sympathy to these situations. Project officers need to be out and about quickly seeing farmers with stewardship agreements to issue prompt derogations and DEFRA needs to keep a financial pot to provide grant aid to farmers faced with sudden costs.

Since this article was published, the CLA's Director North Dorothy Fairburn did write to Defra about measures to mitigate the situation for farmers and landowners affected by the flash flooding. Defra, did respond, and to read more, follow this link.