Jump to content
eggsarascal

Whaley Bridge Evacuated

Recommended Posts

Oh and to top it off, turns out the hydro power scheme won't actually generate any electricity!! It is pumped storage, with the headpond above ground level, and nothing feeding in to it :vollkommenauf:

Share this post


Link to post
Share on other sites
23 hours ago, eggsarascal said:

From a bloke that used to run a business on the cut in that area.

 

The Macc is fed by Toddbrook, not the river Goyt.
 

Okay so the Todbrook after it leaves the dam is largely enclosed as it follows the route I suggested, the slipway and spillway take excess to the Goyt.

Share this post


Link to post
Share on other sites

An annotated map would be wile useful in these meanderings debates about wot water flows where an why.

Edited by difflock
  • Like 1

Share this post


Link to post
Share on other sites
9 hours ago, difflock said:

An annotated map would be wile useful in these meanderings debates about wot water flows where an why.

Here's a quick sketch of my take on this from looking at the map.

 

The Combs  and Toddbrook reservoirs (dark green) feeders (yellow) fill the High Peak Canal (canals use a lot of water when boats go through the locks, about 30 tonnes in our local canal as the locks hold two 70ft narrow boats).

 

Because the canals follow the contour and the Goyt is lower than the canal after Whalley bridge it has to be filled from Toddbrook and Combs reservoirs. Eggs has said it is also filled via the Macclesfield canal and the Bosley reservoir which is 25km from the junction with the high peak canal which starts in Whalley bridge  about 9km south of the junction.

 

The Fernlee and Errwood reservoirs do not seem to feed the canal but presumably also have the function of controlling flow on the Goyt. The trouble is the maps only show open water so I do not know what any of the reservoirs also serve by underground pipes.

 

So the only ways out of the Toddbrook reservoir are via the feeder to the High Peak canal, the weir at the northern tip  and then the overflow that runs  curving clockwise   in front of the dam and thence into the Goyt and the spillway over the top of the dam which meets the above overflow.

 

Any excess that ends up in the High peak canal ( shown red) flows over a weir and into the Goyt (shown light green) near the start of the canal at Whalley bridge.

 

As the Toddbrook reservoir was full, and following very heavy rain, all the excess ended up in the Goyt, which seems to have coped with it, as I said in an earlier post there was the possibility of holding back water at the Fernlee and Errwood reservoirs plus the Combs reservoir if the Goyt could not handle the excess from the Toddbrook system.

 

So it looks like everything worked as planned except the spillway  was damaged when it was over-topped with an unprecedented flow.  I can see the spillway was poorly constructed or maintained for the flow that came over it, Eggs asserts this was predictable and attempt should have been made earlier to lower the level of the Toddbrook reservoir via the overflow into the Goyt if I infer his post correctly.

 

whalleybridge.thumb.jpg.a6dbb099bd59535820ba809994788afe.jpg

 

My personal guess is that there wasn't much of a void below the spillway slabs prior to it being over-topped and the damage was all done during the surge because the joints between the slabs had  deteriorated.

  • Like 1

Share this post


Link to post
Share on other sites
48 minutes ago, openspaceman said:

Here's a quick sketch of my take on this from looking at the map.

 

The Combs  and Toddbrook reservoirs (dark green) feeders (yellow) fill the High Peak Canal (canals use a lot of water when boats go through the locks, about 30 tonnes in our local canal as the locks hold two 70ft narrow boats).

 

Because the canals follow the contour and the Goyt is lower than the canal after Whalley bridge it has to be filled from Toddbrook and Combs reservoirs. Eggs has said it is also filled via the Macclesfield canal and the Bosley reservoir which is 25km from the junction with the high peak canal which starts in Whalley bridge  about 9km south of the junction.

 

The Fernlee and Errwood reservoirs do not seem to feed the canal but presumably also have the function of controlling flow on the Goyt. The trouble is the maps only show open water so I do not know what any of the reservoirs also serve by underground pipes.

 

So the only ways out of the Toddbrook reservoir are via the feeder to the High Peak canal, the weir at the northern tip  and then the overflow that runs  curving clockwise   in front of the dam and thence into the Goyt and the spillway over the top of the dam which meets the above overflow.

 

Any excess that ends up in the High peak canal ( shown red) flows over a weir and into the Goyt (shown light green) near the start of the canal at Whalley bridge.

 

As the Toddbrook reservoir was full, and following very heavy rain, all the excess ended up in the Goyt, which seems to have coped with it, as I said in an earlier post there was the possibility of holding back water at the Fernlee and Errwood reservoirs plus the Combs reservoir if the Goyt could not handle the excess from the Toddbrook system.

 

So it looks like everything worked as planned except the spillway  was damaged when it was over-topped with an unprecedented flow.  I can see the spillway was poorly constructed or maintained for the flow that came over it, Eggs asserts this was predictable and attempt should have been made earlier to lower the level of the Toddbrook reservoir via the overflow into the Goyt if I infer his post correctly.

 

whalleybridge.thumb.jpg.a6dbb099bd59535820ba809994788afe.jpg

 

My personal guess is that there wasn't much of a void below the spillway slabs prior to it being over-topped and the damage was all done during the surge because the joints between the slabs had  deteriorated.

What you infer is correct, CaRT could, and should have started draining earlier. Do they have a telemetry system on their reservoirs to notify them that they are overtopping at an alarming rate?, either way the slipway failed due to lack of maintenance. Some years back some Herbert decided lowering the levels on the network was a good idea due to most of the water being lost was from the top six inches?, what he forgot was those six inches dry out and become incapable of retaining water when the capacity is needed. We still haven't worked out why the Goyt wasn't utilised when it had only just gone into flood. I might be a conspiracy theorist but I'd have a tenner with anyone that the reason is CaRT we're afraid of running out of water later in the year.

Share this post


Link to post
Share on other sites
15 minutes ago, eggsarascal said:

 either way the slipway failed due to lack of maintenance.

I think you mean spillway?

 

The reason is there was ambiguity early on with the  word slipway. It was used to refer to a point at the North of the reservoir where there seems to be a boating club and its slipway (I marked it on my sketch as "SLIP"). At this point there is also a weir where water leaves the reservoir and falls into the normal outflow, it seems to fall into the part of the Toddbrook  that has skirted the northern edge of the reservoir and then enters the curved outflow channel that runs in front of the dam and on into the Goyt.

 

There are weirs also at the upstream entry to the Toddbook  reservoir and halfway to the dam on the northern edge which allow water to divert into this part of the diverted Toddbrook and go directly to the outflow, although trying to interpret the map is not easy.

Share this post


Link to post
Share on other sites
1 minute ago, openspaceman said:

I think you mean spillway?

 

The reason is there was ambiguity early on with the  word slipway. It was used to refer to a point at the North of the reservoir where there seems to be a boating club and its slipway (I marked it on my sketch as "SLIP"). At this point there is also a weir where water leaves the reservoir and falls into the normal outflow, it seems to fall into the part of the Toddbrook  that has skirted the northern edge of the reservoir and then enters the curved outflow channel that runs in front of the dam and on into the Goyt.

 

There are weirs also at the upstream entry to the Toddbook  reservoir and halfway to the dam on the northern edge which allow water to divert into this part of the diverted Toddbrook and go directly to the outflow, although trying to interpret the map is not easy.

Yes, spillway. How many times have I got that wrong in this thread...?

Share this post


Link to post
Share on other sites
1 hour ago, openspaceman said:

Here's a quick sketch of my take on this from looking at the map.

 

The Combs  and Toddbrook reservoirs (dark green) feeders (yellow) fill the High Peak Canal (canals use a lot of water when boats go through the locks, about 30 tonnes in our local canal as the locks hold two 70ft narrow boats).

 

Because the canals follow the contour and the Goyt is lower than the canal after Whalley bridge it has to be filled from Toddbrook and Combs reservoirs. Eggs has said it is also filled via the Macclesfield canal and the Bosley reservoir which is 25km from the junction with the high peak canal which starts in Whalley bridge  about 9km south of the junction.

 

The Fernlee and Errwood reservoirs do not seem to feed the canal but presumably also have the function of controlling flow on the Goyt. The trouble is the maps only show open water so I do not know what any of the reservoirs also serve by underground pipes.

 

So the only ways out of the Toddbrook reservoir are via the feeder to the High Peak canal, the weir at the northern tip  and then the overflow that runs  curving clockwise   in front of the dam and thence into the Goyt and the spillway over the top of the dam which meets the above overflow.

 

Any excess that ends up in the High peak canal ( shown red) flows over a weir and into the Goyt (shown light green) near the start of the canal at Whalley bridge.

 

As the Toddbrook reservoir was full, and following very heavy rain, all the excess ended up in the Goyt, which seems to have coped with it, as I said in an earlier post there was the possibility of holding back water at the Fernlee and Errwood reservoirs plus the Combs reservoir if the Goyt could not handle the excess from the Toddbrook system.

 

So it looks like everything worked as planned except the spillway  was damaged when it was over-topped with an unprecedented flow.  I can see the spillway was poorly constructed or maintained for the flow that came over it, Eggs asserts this was predictable and attempt should have been made earlier to lower the level of the Toddbrook reservoir via the overflow into the Goyt if I infer his post correctly.

 

whalleybridge.thumb.jpg.a6dbb099bd59535820ba809994788afe.jpg

 

My personal guess is that there wasn't much of a void below the spillway slabs prior to it being over-topped and the damage was all done during the surge because the joints between the slabs had  deteriorated.

70'10" goes into all the looks on the K@A, sling the boat in on her own and 72' will go in. The difference with the K@A to most other cuts is the back pumps at Foxhangers, so the same storage isn't needed. Is it something like 5 million gallons pump back up on a busy day?

Share this post


Link to post
Share on other sites
34 minutes ago, eggsarascal said:

Yes, spillway. How many times have I got that wrong in this thread...?

I only noticed it then.

 

Incidentally googlearth shows it empty in 1945 (and no sign of water in the canal but it is B&W so hard to tell)and no spillway visible, all the later photos show it at well below capacity  with most of the boat slipway showing.

16 minutes ago, eggsarascal said:

70'10" goes into all the looks on the K@A, sling the boat in on her own and 72' will go in. The difference with the K@A to most other cuts is the back pumps at Foxhangers, so the same storage isn't needed. Is it something like 5 million gallons pump back up on a busy day?

Yes they back pump for the Caen Hill flight because there is no water at the top of the flight to make up and I think they had to do this from the beginning with steam pumps. Even with limited pumping the one by me tends to be shut for navigation from June till the Autumn, it was only re opened in 1991 after being closed for 50 years.

Share this post


Link to post
Share on other sites
41 minutes ago, openspaceman said:

I only noticed it then.

 

Incidentally googlearth shows it empty in 1945 (and no sign of water in the canal but it is B&W so hard to tell)and no spillway visible, all the later photos show it at well below capacity  with most of the boat slipway showing.

Yes they back pump for the Caen Hill flight because there is no water at the top of the flight to make up and I think they had to do this from the beginning with steam pumps. Even with limited pumping the one by me tends to be shut for navigation from June till the Autumn, it was only re opened in 1991 after being closed for 50 years.

I was going to get above myself and say Foxton used to be back pumped, the more I think about it the boiler house was there to power the inclined plane, probably the prettiest place 

 on the cut IMO.

Edited by eggsarascal

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Featured Adverts

About

Arbtalk.co.uk is a hub for the arboriculture industry in the UK.  
If you're just starting out and you need business, equipment, tech or training support you're in the right place.  If you've done it, made it, got a van load of oily t-shirts and have decided to give something back by sharing your knowledge or wisdom,  then you're welcome too.
If you would like to contribute to making this industry more effective and safe then welcome.
Just like a living tree, it'll always be a work in progress.
Please have a look around, sign up, share and contribute the best you have.

See you inside.

The Arbtalk Team

Follow us

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.