Flooded rural roads and the impact flooding has on them.

[Andy W]

Over the last few months I've regularly cycled a 35 mile circular route in North Herts, on quiet rural lanes. Occasionally,  some roads are literally impassable by bike as the water is too deep, not that it's a problem, I simply reroute.  What puzzles me is the damage this flooding causes. Some potholes are so deep and appear almost overnight.  Nowadays my go to bike is a Genesis CDF shod with 40mm gravel tyres, full mudguards with obligatory oversized mudflaps. Speed is unimportant as I'm simply attempting to be cycling specific fit.
I digress.  These same roads I used to cycle down 35 years ago on 23c tyres  is but a dream now. I can see the attraction of gravel bikes if only to tackle uks crumbling road network. I gave my decent roadbike to my son 3 years ago as there's no way I can ride it unless I go on A and B roads. That's not going to happen. My audax speed will be compromised as I'll be riding a heavier fatter tyred bike. If I were in the market for n+1 I'd buy a lightweight 11.5kg MTB hardtail.

[mrcharly-YHT]

More and heavier traffic.

Damage to surface, water penetrates and weakens underlying structure, heavy traffic breaks it up in hours.

[LittleWheelsandBig]

Yup. Saturated road pavement materials usually have reduced shear strength, which isn’t good. This is why road trains can get bogged in lightly sealed roads in the Outback, if recently flooded roads haven’t dried out enough.

The rapid changes in hydraulic pressure caused as heavy wheel loads roll across fully saturated materials can effectively ‘blow’ them apart, which is even worse for causing potholes.

[Jaded]

Wider tyres, heavier vehicles and more traffic.

Frost makes a crack, it fills with water, a wide tyre gives no place for the water to escape, so there is big hydraulic pressure from the water in the crack. Potholes in hours.

[ElyDave]

Wider tyres, heavier vehicles and more traffic.

Frost makes a crack, it fills with water, a wide tyre gives no place for the water to escape, so there is big hydraulic pressure from the water in the crack. Potholes in hours.

Very much this in TEH FENZ, coupled with the roads being on elevated causeway, so they dry out and drop in the summer  opening up more cracks for the frost in the winter.  There are now roads i avoid by car as they are like a rollercoaster even in a 4x4.

[mrcharly-YHT]

Wider tyres, heavier vehicles and more traffic.

Frost makes a crack, it fills with water, a wide tyre gives no place for the water to escape, so there is big hydraulic pressure from the water in the crack. Potholes in hours.

Very much this in TEH FENZ, coupled with the roads being on elevated causeway, so they dry out and drop in the summer  opening up more cracks for the frost in the winter.  There are now roads i avoid by car as they are like a rollercoaster even in a 4x4.

I remember taking a back road to a little village; boy did I regret it. Impossible to go over 15mph for some distance. Rollercoaster doesn't describe it. It was like driving over speed pillows, spaced a metre or so apart, for miles.

[LittleWheelsandBig]

Most of that was probably movement within clay subgrade, rather than within road pavement layers. Cracking (from frost and/or subgrade movement) through the pavement layers would let water into/ out of the subgrade.

[Asterix, the former Gaul.]

Wider tyres, heavier vehicles and more traffic.

Frost makes a crack, it fills with water, a wide tyre gives no place for the water to escape, so there is big hydraulic pressure from the water in the crack. Potholes in hours.

Very much this in TEH FENZ, coupled with the roads being on elevated causeway, so they dry out and drop in the summer  opening up more cracks for the frost in the winter.  There are now roads i avoid by car as they are like a rollercoaster even in a 4x4.

I remember taking a back road to a little village; boy did I regret it. Impossible to go over 15mph for some distance. Rollercoaster doesn't describe it. It was like driving over speed pillows, spaced a metre or so apart, for miles.

It's caused by vehicle suspensions.  The road surface is repeatedly pounded at specific points by the momentum of the suspension.  Once degradation starts it can only get worse.  Most likely on farm tracks and rural back roads where a specific type of heavy vehicle frequently uses it.

[chrisbainbridge]

One word: Austerity. Decent investment in roads and drainage over the last 15 years would have left us in a much better position even with the current record breaking winter. I am thinking of sending this view to everybody in our village come the election as flooding has increased every year and so far this winter alone we have houses that have had to contend with flooding up to or over the doorstep 8 times.

[MikeFromLFE]

Perhaps not directly related to the road surface issue is the effect of building on green areas that previously allowed water to drain away now causing flooding in areas that have never seen these volumes of water before.

The major local example (Leicestershire) is the rapid development of a new 'town' on the western edge of Leicester - New Lubbesthorpe - on a green field site. The surrounding roads are now seeing flooding and standing surface water where this has never happened in the last 35 years.

Another very minor local example is our garden which has flooded this winter - again for the first time in 35 years - and we, and our same-suffering neighbours, are convinced it's only because of the recently constructed car park at the nearby school - again on what was previously grass.

In my premise there's a lot more water on roads that previously would have drained away slowly. That water is causing the surface damage instead of draining naturally.

[Jaded]

More rain.
Removal of run off alleviation mechanisms, such as trees.
More building.
Building hard infrastructure to deal with water, rather than soft such as slowing streams down.
Not enforcing SUDS instead of hard surfaces.

[drossall]

Over the last few months I've regularly cycled a 35 mile circular route in North Herts, on quiet rural lanes. Occasionally,  some roads are literally impassable by bike as the water is too deep, not that it's a problem, I simply reroute.  What puzzles me is the damage this flooding causes.

I'm also in North Herts. I've not been in the lanes much lately, but hadn't noticed too much of an issue. Certainly my club will be racing this spring and summer, on back roads just over the border in Mid Beds. We'll be on lightweight bikes and wheels for that without undue concern, I'd think.

Road damage does happen in winter from freezing and general bad weather. I am being unduly complacent? Or should I get out more?!

[Andy W]

Hey Drossall, ex Hitchin Nomad here. Roads impassable are at, Shilley Green Farm, near Easthall/Langley. Luffenhall/ Cromer, river Beane overflows and between Moor Green and Great Munden. Admittedly these are very narrow rural roads, lightly used and ideal for MTB/ gravel bike use or at least 40mm tyres.
As im familiar Briercliffe 10 course, id agree its unlikely to be flooded to the extent time trialling will be cancelled. I might even have a go. Feel free to time me with a diary

[drossall]

Yes, those are great roads to ride, at least when passable.

There's a calendar on the home page here. I set it up a few weeks ago (but I'm not the main Webmaster). Click through for details and courses. This year, we're sharing with the Beds Roads, so about half of events are organised by them, on roads in or near to Cardington.

[Kim]

To be fair, it's not like urban roads are much better.

(This post sponsored by the state of my trousers after misjudging the flying leap required to push a wheelchair through the perpetual puddle by the dropped kerb at the Southgate earlier this afternoon.  It's almost directly above a culvert.  Shirley a 5 minute job for someone with a gully sucker and/or a set of rods.)

[Lightning Phil]

A number of the floods in Herts would be avoided if the original drainage ditches hadn’t been left to basically silt up. Though as the Met Office published, rainfall is 30% above the historical averages of 1990 to 2010 for Herts. Plus being mostly clay other than the chalk escarpments and thus doesn’t drain well.

[rafletcher]

Yesterday I collected a new-to-me car. That involved a 40 mile drive from Tring to Oxford, and I opted for the route via Thame. Never have I experienced such broken and potholed surfaces, allied to a significant amount of surface water. I was glad I was driving (small) SUV’s with reasonably high side walled tyres. I’d hate to cycle the majority of those roads now.

[rogerzilla]

More rain.
Removal of run off alleviation mechanisms, such as trees.
More building.
Building hard infrastructure to deal with water, rather than soft such as slowing streams down.
Not enforcing SUDS instead of hard surfaces.

SUDS is ignored by most driveway contractors, judging from those installed around here.  Digging a soakaway is expensive and there may not be space for one, so onto the road it goes with no intercepting channel.  No permission is required unless you want a dropped kerb, so the council, or whoever cares about drainage, wouldn't even know.

[Jaded]

Collapsing infrastructure too...





Here's two images from a CCTV survey, done after extensive floods. Crushed and blocked pipes, surveys abandoned because of blockages, other pipes and conduits driven through drainage pipes.

[Frank9755]

It is true that many roads are in a poor state of repair.  However I find urban roads far more of a problem than in the country and believe the roads in Ealing, which I ride most, to be worse than they have ever been.

But - and excuse my being controversial - I believe that the roads in the area of the Chilterns where I ride most to be in a better state than they were 10 years ago.  I've organised a reliability ride for the last 10 years and, each year, I ride the route and note any hazards including areas of poor surface.  What I've found is that these roads were at their worst about 8 years ago and are now in a better state overall than at any time during the period I've been systematically checking them.

I realise this is not representative of anywhere else or any other council areas and doesn't compare with pre-austerity era.

[markcjagar]

It is true that many roads are in a poor state of repair.  However I find urban roads far more of a problem than in the country and believe the roads in Ealing, which I ride most, to be worse than they have ever been.

But - and excuse my being controversial - I believe that the roads in the area of the Chilterns where I ride most to be in a better state than they were 10 years ago.  I've organised a reliability ride for the last 10 years and, each year, I ride the route and note any hazards including areas of poor surface.  What I've found is that these roads were at their worst about 8 years ago and are now in a better state overall than at any time during the period I've been systematically checking them.

I realise this is not representative of anywhere else or any other council areas and doesn't compare with pre-austerity era.

City councils probably have to spread their budgets more thinly than more rural councils. Also, stop/start traffic is worse for roads than steady rolling traffic.

that and the Labour councils of cities are being underfunded compared to Conservative councils in rural areas

Why roads are the responsibility of local councils and not the DfT is something I'd like to enquire

[ElyDave]

To be fair, the farmers and drainage boards around here do a great job maintaining all of the ditches,  it's just that there is too much water around at the moment, 2 x 50km in different directions over the weekend and flooded fields on all sides. Roads being set up on causeways are dry but need you to weave between the unbroken bits

[Lightning Phil]

There was a weather thing on Countryfile tonight. It showed the rainfall for Cardiff this February is 7 times the norm. If my recollection is correct.

[Lightning Phil]

Plus there’s this, which shows even in 2020, uk February rainfall was 237% the average February rainfall of 1981 to 2020. 

https://www.metoffice.gov.uk/about-us/press-office/news/weather-and-climate/2020/2020-winter-february-stats

[Bledlow]

Mrs B had a rant recently about British roads. As she rightly said, they're much better maintained in Japan.

Japan has lots of rainfall, & is densely populated, so apart from the southern areas that don't freeze, one would expect the same problems we have here, but they seem to be much, much less. I don't think one can even put it all down to less spending (though some of it, yes). I think the quality of work here is lower, in general, & local authorities who are the customers accept that low quality. For example, our street was resurfaced not long ago. Patches of the surface started breaking up immediately: instant potholes. It's not the only street I've seen that happen to, & I've not seen the contractors brought back to fix it, despite complaints from residents.

The standard of road repairs after assorted owners of buried infrastructure dig holes is also poor. We have a hollow in our street because several years ago Thames Water didn't restore the road surface to where it was after a burst pipe washed out enough soil to cause subsidence around a hole. They filled in the hole level with the lowered edges. Again, they weren't brought back to put it right.