Having walked the length of most of the storm reliefs and lost rivers I thought I'd take a look at some of the bigger pipes that make up London's drainage system. Bazelgette is famous for designing and overseeing the construction of the Interceptors, which on both sides of the Thames flow from west to east to the pumping stations and sewage works, intercepting all the sewers that used to pollute the Thames. Generally you can't walk in them as during the 'waking' hours they're far too full and fast flowing but in the very early hours it gets a bit easier. There wasn't a great deal of walking involved as most of them are quite featureless for long distances. Usually, it was a case of going in and out of the same lid
Mid Level No.1 - Farringdon
Some of you may remember a report I wrote ages ago about an interesting part of the Mid Level, where it interacts with an odd by-pass pipe, the Fleet Storm Relief, the Fleet and the Metropolitan railway. I didn't know about the by-pass at the time and couldn't really see the Aqueduct because I'd gone too early and there was too much flow. The Fleet Storm Relief was built after the Mid Level was so I can only assume the bypass pipe was used (possibly in conjuction with the Ranelagh Relief on the mid level) to bypass the overflow/ drop shaft connection to the Fleet Relief while it was being built. It's not particularly exciting and has now been bricked up. Just upstream is where the Fleet Branch of the Mid Level joins. I must've seen it but not photographed it. Dunno why - maybe it was too slippery to bother setting up a tripod......
Overflow to Fleet Relief and dropshaft. Apparently TW or their subbies didn't check the weather or forgot their youngman board one evening. Somehow, I suspect this is supposed to be at the top of the shaft with the rest of their kit. I couldn't even see this shaft from above last time as the grill was so covered in rags. Perhaps it was reducing the effectiveness of the overflow and this is why they were doing the work.
Looking upstream towards the other end of the by-pass section.
The overflow to the Fleet CSO on the right just before the aqueduct over the Metropolitan Railwway
Behind the penstock on the right is a very confined chamber with all the penstocks workings and a steep, cast iron / brick slide which drops into the fleet sewer
Aqueduct on the left
This is looking upstream through the aqueduct. Arch on the left leads to another original overflow into a 4ft pipe. This follows the railway for a short distance and i suspect it leads to the Fleet. Arch on the right is just a local sewer IIRC and the square opening on the right is a concrete side entry
The Low Level No.1 at The Embankment
A surveying company had the privilege of surveying every part of Blackfriars Bridge (Fleet Storm Relief not shown
)
First up this is not a place to get caught out. Most of the lids downstream are heavy split lids. If it's rained in the passed few days, the tide's in, it's the weekend or 'not very late yet' don't even set foot foot in it - wait till tideway's done
In fact just don't set foot in it at all
This is a short distance upstream of the Fleet (so part of JBizzles Victoria Embankment) and I've no idea what it is. Does anyone else?
Tree roots penetrate the gully pipes in search of water. Every gully by the looks of it. Rags collect on the roots.
A familiar penstock to anyone that's walked the corridors at the end of the Fleet / Storm Relief. The two Fleet pipes which cross the Low Level are visible just a bit further down
This section interested me (as you might expect). The majority of JB's interceptor scheme was complete by the late 1860's, the only thing that wasn't complete was the Low Level No.1. This was because it was decided to built it alongside the Thames Embankment, itself a massive undertaking. The River Wall had to be built, the swampy Thames bank drained, ballast brought in, the District Line built, the utility tunnels, the roadway and the arches that it's built on, the public gardens, everything! It was started in 1865 and wasn't completed until 1870. I came across this site which give more detail on the construction of the Victoria Embankment https://wondersofworldengineering.com/embankment.html
Blackfriars Bridge (which replaced an old one built in the same location) opened in 1869. You kinda have to know the area around the Fleet outfall to fully understand but the first arch starts above the road (not the river) The rather lovely brick chamber at the end of the Fleet Sewer / Storm Relief is further inland than you would expect so it could discharge straight to the then adjacent Thames / old Fleet Estuary through the bridge abutment. The sewer was extended in the 1960's when the roadway and realigned river wall beneath the bridge were built. What surprised me is that all the brickwork in the Low Level is the same and they appeared to have built the whole lot in one go. No part of the Interceptor, at least, appears to have been rebuilt, cut into or added to in anyway.....So they knew the Fleet was going to need a storm relief before the Low Level Interceptor and the Embankmnet were complete.......Maybe that's why the bypass section on the Mid Level looks so neat as well because they'd already planned to build the Storm Relief.
The interceptor is wider here to make up for the reduced height. The Fleet Storm Relief is the one closest to me. It was constructed between 1872 and 1875, much earlier than most of London's Storm Reliefs.
Where the flow from the Fleet sewer goes. This was a lot smaller than I expected. Most of the connections to the Low Level are this size whether they come from a big lost river or a 4ft local sewer.
I went back to the penstock and climbed up to take another look at the Fleet. Flow goes down to the right and into the Low Level just the other side of the short weir wall. The area with the yellow brick is directly above the Low Level Interceptor. I'd not noticed the concrete patch and the red bricks on the left on previous visits. The storm relief is just the other side of that wall
The Fleet was practically empty and what was flowing in it was very clear
Some of these are old pics, taken on a visit with @Conrad showing the outfall chamber where storm flows from the sewer and storm relief combine.
One of two brick pipes leading to the Thames - the 60's extension?
From the other pipe but looking back up towards the enormous flaps and tumbling bay. The white sticker on the Steel plates reads "PROPERTY OF LONDON UNDERGROUND IF FOUND PLEASE CONTACT OUR NETWORK OPERATIONS CENTRE ON........".
Low Level No.1&2 Balancer Chamber
After checking a few other drains I went to see if I could find the first balancer chambers between the two Low Level Interceptors near Mansion House. There's another one further downstream and two similar set ups between the 1st and 2nd Low Level Interceptors South of the Thames. My understanding is that they can balance each other out if one is substantially higher than the other. Penstocks are provided in all three directions so the downstream flow from one Interceptor at a time can be completely shut off. Being quite confined the counter balance weights, chains and pulleys are arranged in quite a photogenic way. It sounds obvious but before the Low Level No.2 was built there was just the original Low Level No.1 here. The Low Level No.1 is built of yellow Gault bricks. The blue and the red engineering bricks were laid by the LCC in the first decade of the 1900's when both of these chambers were built.
Mid Level No.1 - Farringdon
Some of you may remember a report I wrote ages ago about an interesting part of the Mid Level, where it interacts with an odd by-pass pipe, the Fleet Storm Relief, the Fleet and the Metropolitan railway. I didn't know about the by-pass at the time and couldn't really see the Aqueduct because I'd gone too early and there was too much flow. The Fleet Storm Relief was built after the Mid Level was so I can only assume the bypass pipe was used (possibly in conjuction with the Ranelagh Relief on the mid level) to bypass the overflow/ drop shaft connection to the Fleet Relief while it was being built. It's not particularly exciting and has now been bricked up. Just upstream is where the Fleet Branch of the Mid Level joins. I must've seen it but not photographed it. Dunno why - maybe it was too slippery to bother setting up a tripod......
Overflow to Fleet Relief and dropshaft. Apparently TW or their subbies didn't check the weather or forgot their youngman board one evening. Somehow, I suspect this is supposed to be at the top of the shaft with the rest of their kit. I couldn't even see this shaft from above last time as the grill was so covered in rags. Perhaps it was reducing the effectiveness of the overflow and this is why they were doing the work.
Looking upstream towards the other end of the by-pass section.
The overflow to the Fleet CSO on the right just before the aqueduct over the Metropolitan Railwway
Behind the penstock on the right is a very confined chamber with all the penstocks workings and a steep, cast iron / brick slide which drops into the fleet sewer
Aqueduct on the left
This is looking upstream through the aqueduct. Arch on the left leads to another original overflow into a 4ft pipe. This follows the railway for a short distance and i suspect it leads to the Fleet. Arch on the right is just a local sewer IIRC and the square opening on the right is a concrete side entry
The Low Level No.1 at The Embankment
A surveying company had the privilege of surveying every part of Blackfriars Bridge (Fleet Storm Relief not shown
)
First up this is not a place to get caught out. Most of the lids downstream are heavy split lids. If it's rained in the passed few days, the tide's in, it's the weekend or 'not very late yet' don't even set foot foot in it - wait till tideway's done
In fact just don't set foot in it at allThis is a short distance upstream of the Fleet (so part of JBizzles Victoria Embankment) and I've no idea what it is. Does anyone else?
Tree roots penetrate the gully pipes in search of water. Every gully by the looks of it. Rags collect on the roots.
A familiar penstock to anyone that's walked the corridors at the end of the Fleet / Storm Relief. The two Fleet pipes which cross the Low Level are visible just a bit further down
This section interested me (as you might expect). The majority of JB's interceptor scheme was complete by the late 1860's, the only thing that wasn't complete was the Low Level No.1. This was because it was decided to built it alongside the Thames Embankment, itself a massive undertaking. The River Wall had to be built, the swampy Thames bank drained, ballast brought in, the District Line built, the utility tunnels, the roadway and the arches that it's built on, the public gardens, everything! It was started in 1865 and wasn't completed until 1870. I came across this site which give more detail on the construction of the Victoria Embankment https://wondersofworldengineering.com/embankment.html
Blackfriars Bridge (which replaced an old one built in the same location) opened in 1869. You kinda have to know the area around the Fleet outfall to fully understand but the first arch starts above the road (not the river) The rather lovely brick chamber at the end of the Fleet Sewer / Storm Relief is further inland than you would expect so it could discharge straight to the then adjacent Thames / old Fleet Estuary through the bridge abutment. The sewer was extended in the 1960's when the roadway and realigned river wall beneath the bridge were built. What surprised me is that all the brickwork in the Low Level is the same and they appeared to have built the whole lot in one go. No part of the Interceptor, at least, appears to have been rebuilt, cut into or added to in anyway.....So they knew the Fleet was going to need a storm relief before the Low Level Interceptor and the Embankmnet were complete.......Maybe that's why the bypass section on the Mid Level looks so neat as well because they'd already planned to build the Storm Relief.
The interceptor is wider here to make up for the reduced height. The Fleet Storm Relief is the one closest to me. It was constructed between 1872 and 1875, much earlier than most of London's Storm Reliefs.
Where the flow from the Fleet sewer goes. This was a lot smaller than I expected. Most of the connections to the Low Level are this size whether they come from a big lost river or a 4ft local sewer.
I went back to the penstock and climbed up to take another look at the Fleet. Flow goes down to the right and into the Low Level just the other side of the short weir wall. The area with the yellow brick is directly above the Low Level Interceptor. I'd not noticed the concrete patch and the red bricks on the left on previous visits. The storm relief is just the other side of that wall
The Fleet was practically empty and what was flowing in it was very clear
Some of these are old pics, taken on a visit with @Conrad showing the outfall chamber where storm flows from the sewer and storm relief combine.
One of two brick pipes leading to the Thames - the 60's extension?
From the other pipe but looking back up towards the enormous flaps and tumbling bay. The white sticker on the Steel plates reads "PROPERTY OF LONDON UNDERGROUND IF FOUND PLEASE CONTACT OUR NETWORK OPERATIONS CENTRE ON........".
Low Level No.1&2 Balancer Chamber
After checking a few other drains I went to see if I could find the first balancer chambers between the two Low Level Interceptors near Mansion House. There's another one further downstream and two similar set ups between the 1st and 2nd Low Level Interceptors South of the Thames. My understanding is that they can balance each other out if one is substantially higher than the other. Penstocks are provided in all three directions so the downstream flow from one Interceptor at a time can be completely shut off. Being quite confined the counter balance weights, chains and pulleys are arranged in quite a photogenic way. It sounds obvious but before the Low Level No.2 was built there was just the original Low Level No.1 here. The Low Level No.1 is built of yellow Gault bricks. The blue and the red engineering bricks were laid by the LCC in the first decade of the 1900's when both of these chambers were built.
Well fed up of lockdown and short days too. Bring on spring
