Building a Culvert

[Barney12]

OK, so I've got this lovely leat that runs across my land which is fed from the open moor. Where it passes under the driveway there is a 300mm pipe which is a complete PITA as it blocks pretty much every winter and floods the driveway as all manor of foliage and leaves, branches etc head down the leat in wet/stormy weather. So I need some options. Unfortunately I've not got a lot of height to play with so installing say a 600mm pipe isn't possible. I could put two 300mm pipes side by side but every local I speak to says the same thing (thick Devon accent require) "them there pipes will jus blok up boy". 

 

So my mind is moving to building a square channel culvert.....

 

This is a big commercial version:

 

 

All the commercial options are HUGE and custom build is crazy money. 

 

So two options:

 

Try and build it insitu (not simple as the water would need diverting so concrete can dry) or create the concrete sections (shuttering, rebar etc) and lower into place (I've got an 8T machine onsite). 

 

But what about the top? Its going to need to take vehicle traffic. Re-enforced concrete with rebar again? 

 

The total width is about 3m and I could go as wide as say 1m.

 

Will this work? Better options? Am I mad? Am I overthinking? (the last two answers are yes and always!)

[Jeremy Harris]

We have lots of drive bridges over the village stream here.  All are built the same way, a couple of steel UBs covered over with railway sleepers.  I'll try and wander around and take some photos of them later.  None are more than about a foot above the stream normal water level at their lowest point.  At a guess I'd say the UBs might be around 8 inches deep, then there's the thickness of the sleepers on top.  I'll try and get some measurements when I'm out taking photos later.  Several of these bridges look as if they've been there a few decades, so they seem to last OK.

 

These bridges are also pretty strong.  My neighbour over the road has had a few dozen 18 wheel tipper trucks in and out over the last month or two, and his bridge doesn't seem to be any the worse for it.

[Barney12]

1 minute ago, JSHarris said:

We have lots of drive bridges over the village stream here.  All are built the same way, a couple of steel UBs covered over with railway sleepers.  I'll try and wander around and take some photos of them later.  None are more than about a foot above the stream normal water level at their lowest point.  At a guess I'd say the UBs might be around 8 inches deep, then there's the thickness of the sleepers on top.  I'll try and get some measurements when I'm out taking photos later.  Several of these bridges look as if they've been there a few decades, so they seem to last OK.

 

These bridges are also pretty strong.  My neighbour over the road has had a few dozen 18 wheel tipper trucks in and out over the last month or two, and his bridge doesn't seem to be any the worse for it.

 

This is why I LOVE this forum! 

[Ralph]

I'm in a similar position, although the water only appears once every couple of years during flooding. Everyone tells me that culverts are built to be blocked. One piece of advice is to dig it out so the water has somewhere to go and bridge it with long railway sleepers, not convinced at all by this.

I've been looking here https://www.drainage-channel.co.uk/category-6086/DCGT400.html

 

[Barney12]

7 minutes ago, Ralph said:

I'm in a similar position, although the water only appears once every couple of years during flooding. Everyone tells me that culverts are built to be blocked. One piece of advice is to dig it out so the water has somewhere to go and bridge it with long railway sleepers, not convinced at all by this.

I've been looking here https://www.drainage-channel.co.uk/category-6086/DCGT400.html

 

 

Thanks. Mine runs pretty much all year but can turn into a fast running river in very wet weather due the huge catchment area and huge fall. 

That one you've linked to isn't going to be big enough for me but looks viable for some.

I've also found these guys who are the only one I've found that make a smaller unit. Alas I'm still waiting for a quote and suspect they've little appetite for the self builder!

https://www.stanton-bonna.co.uk/drainage-systems/compact-culverts/ 

[Ralph]

Just now, Barney12 said:

That one you've linked to isn't going to be big enough for me but looks viable for some.

 

Yeah I just realised after posting that it would be useless for you, and me to be honest. @JSHarris solution with the steel UBs makes sense and probably more cost effective. It's either that or a ford for me.

[ProDave]

Not sure about the EA, but up here you need permission from SEPA to culvert a watercourse.

 

Ours is culverted in several places by big steel "tubes" that I am sure had some previous industrial use. They are about 1 metre square with flanges on the end, so several sections could bolt together and what is now the "top" has ladder rungs welded to it, which makes me think in it's previous life these were mounted vertically.

 

My neighbour (with permission from SEPA) just cast concrete strip foundations along the top of each bank, and then bridged the span with pre cast (probably pre stressed) flat concrete panels that were lifted into place.  But I think he has built in a time bomb, because he now has several metres of the original bank that no longer gets daylight, so nothing will grow.  And with no vegetation I fear in spate the soil is going to get washed away over time from under his strip foundations.

[Ferdinand]

Try talking to Stanton Bonna, and also Buildbase Civils.

 

BC have a branch 2 miles away and they have some quite big stuff that I see when I get big slabs.

 

Once talked to SB about a section of concrete tunnel to use as a round wine cellar; whackos do phone them up.

Edited August 20, 2019 by Ferdinand

[Russell griffiths]

We dug out an old pipe a few years back as it was blocking constantly 

we then cut the ends off of 3 45 gallon drums and chucked them in the stream so the water flowed through them, cover the top in two layers of reinforcement mesh and 150mm of concrete, as the drums rust away it leaves a perfect shuttered round pipe. 

[Ferdinand]

1 hour ago, JSHarris said:

We have lots of drive bridges over the village stream here.  All are built the same way, a couple of steel UBs covered over with railway sleepers.  I'll try and wander around and take some photos of them later.  None are more than about a foot above the stream normal water level at their lowest point.  At a guess I'd say the UBs might be around 8 inches deep, then there's the thickness of the sleepers on top.  I'll try and get some measurements when I'm out taking photos later.  Several of these bridges look as if they've been there a few decades, so they seem to last OK.

 

These bridges are also pretty strong.  My neighbour over the road has had a few dozen 18 wheel tipper trucks in and out over the last month or two, and his bridge doesn't seem to be any the worse for it.

 

Google street view should do that well enough.

 

Also look at the A6011 in Linby, Notts. The river Lean goes under a number of drives over a Good distance.

 

Edited August 20, 2019 by Ferdinand

[mafaldina]

Have you tried any of the agricultural concrete manufacturers, if you are in Devon someone like Croom Concrete is not very far (Sedgemoor), They make slurry channels etc.

 

[Jeremy Harris]

24 minutes ago, Ferdinand said:

 

Google street view should do that well enough.

 

 

Good idea!  Here goes:

 

 

 

 

 

 

[Pete]

2 hours ago, Barney12 said:

OK, so I've got this lovely leat that runs across my land which is fed from the open moor. Where it passes under the driveway there is a 300mm pipe which is a complete PITA as it blocks pretty much every winter and floods the driveway as all manor of foliage and leaves, branches etc head down the leat in wet/stormy weather. So I need some options. Unfortunately I've not got a lot of height to play with so installing say a 600mm pipe isn't possible. I could put two 300mm pipes side by side but every local I speak to says the same thing (thick Devon accent require) "them there pipes will jus blok up boy". 

 

So my mind is moving to building a square channel culvert.....

 

This is a big commercial version:

 

 

All the commercial options are HUGE and custom build is crazy money. 

 

So two options:

 

Try and build it insitu (not simple as the water would need diverting so concrete can dry) or create the concrete sections (shuttering, rebar etc) and lower into place (I've got an 8T machine onsite). 

 

But what about the top? Its going to need to take vehicle traffic. Re-enforced concrete with rebar again? 

 

The total width is about 3m and I could go as wide as say 1m.

 

Will this work? Better options? Am I mad? Am I overthinking? (the last two answers are yes and always!)

Sounds like it was written by @Onoff? This could give his bathroom a run for its money!! (Hope you get the answers you are looking for)

[PeterW]

I’d build a diversion channel for the leat and then build a proper concrete culvert with a decent base and sides (and front apron) and then close your diversion channel when it’s set. 

 

You can do this in as little as 72 hours, and also allows you to then cap it with concrete using shuttering and rebar. At 1200mm wide, it will only need to be 180mm thick with rebar to hold a car.  

[Cpd]

Have you got loads of stone, time to waste and want it to look great ! Here’s one I built in Australia, must have put about 10 of these in this road each one custom built to fit into its surroundings, if the ground slopes away at the end then consider some sort of retailer / spillway to prevent erosion. 

[mafaldina]

Jeremy, I'm trying to remember where that is, I 'm sure it's somewhere around Ebbersbourne Wake/Alverdiston. Remember it from when I used to live at Donhead.

 

[Jeremy Harris]

1 hour ago, mafaldina said:

Jeremy, I'm trying to remember where that is, I 'm sure it's somewhere around Ebbersbourne Wake/Alverdiston. Remember it from when I used to live at Donhead.

 

 

Fovant, about 3 miles North of Ebbesbourne Wake, maybe 6 miles North East of Donhead.  Our place is a couple of hundred metres downstream from those bridges (the brook runs along the front of our place, on the opposite side of the lane).

[Andrew]

6 hours ago, ProDave said:

Not sure about the EA, but up here you need permission from SEPA to culvert a watercourse.

 

You may well need a land drainage consent - https://www.devon.gov.uk/floodriskmanagement/land-drainage-consent/

 

We were forced to apply for one for installing a head wall into the bank of a tiny stream (ordinary watercourse) as part of discharging our drainage planning condition. 

[Barney12]

2 minutes ago, Andrew said:

 

You may well need a land drainage consent - https://www.devon.gov.uk/floodriskmanagement/land-drainage-consent/

 

We were forced to apply for one for installing a head wall into the bank of a tiny stream (ordinary watercourse) as part of discharging our drainage planning condition. 

 

As I’m replacing an existing culvert ( if you can call a 300mm such) I don’t need any permissions. 

In fact DCC were completely disinterested when I called them and said “speak to the national park” who in turn said “speak to DCC”. Both said if it’s replacing an existing crossing then nothing to inform them of. 

 

[Barney12]

3 hours ago, Cpd said:

Have you got loads of stone, time to waste and want it to look great ! Here’s one I built in Australia, must have put about 10 of these in this road each one custom built to fit into its surroundings, if the ground slopes away at the end then consider some sort of retailer / spillway to prevent erosion. 

 

Crikey that looks lovely! 

[PeterW]

Just now, Barney12 said:

 

As I’m replacing an existing culvert ( if you can call a 300mm such) I don’t need any permissions. 

In fact DCC were completely disinterested when I called them and said “speak to the national park” who in turn said “speak to DCC”. Both said if it’s replacing an existing crossing then nothing to inform them of. 

 

 

I would build a miniature version  of the Tamar bridge and then see what they have to say ..!! 

[Barney12]

5 hours ago, PeterW said:

I’d build a diversion channel for the leat and then build a proper concrete culvert with a decent base and sides (and front apron) and then close your diversion channel when it’s set. 

 

You can do this in as little as 72 hours, and also allows you to then cap it with concrete using shuttering and rebar. At 1200mm wide, it will only need to be 180mm thick with rebar to hold a car.  

 

Chatting to my stone mason on site today this was his advice. 

[Barney12]

Just now, PeterW said:

 

I would build a miniature version  of the Tamar bridge and then see what they have to say ..!! 

 

What I REALLY want is a moat and drawbridge. Oh and a couple of gun turrets ?

[Barney12]

5 hours ago, mafaldina said:

Have you tried any of the agricultural concrete manufacturers, if you are in Devon someone like Croom Concrete is not very far (Sedgemoor), They make slurry channels etc.

 

 

Thanks for the tip. I’ll research that too.

[mafaldina]

4 hours ago, JSHarris said:

 

Fovant, about 3 miles North of Ebbesbourne Wake, maybe 6 miles North West of Donhead.  Our place is a couple of hundred metres downstream from those bridges (the brook runs along the front of our place, on the opposite side of the lane).

Thank you Jeremy. I'm sure there is also a road like that on the 'top' somewhere. A long row and the curates house near the end. Is the Compasses still going, used to have good beer.