Dropbox (CSO), Bradford
Continuing rapid development resulted in Bradford's sewer system becoming inadequate to deal with the rising population
A total of 94 CSO's were constructed in Bradford to prevent sewage flooding due to the lack of capacity of the system from 1870 onwards
The majority of these overflows discharge into the Bradford Beck and its tributaries
Apparently they have been reduced to 15 since 2004, however I have photographic evidence to suggest otherwise
The majority of the CSO's comprise low level single side weirs and operate more than 200 times per year
It is estimated that more than 6 million cubic metres of untreated sewage overflow into the Bradford Beck for over 400 hours every year
In fact the annual volume of CSO spills is nearly 50% of Bradford's total annual rainfall and that 80-90% of the peak originates from the sewer system during a two year return period rainfall event
In total there is over 30,000m³ of storage capacity within the catchment area of the Bradford Beck
One thing I will say about Bradford, it keeps giving (and there is more to come as soon as I can sift through 3 years of pics )
Massive shouts to Squirrell 911 for some of the funniest on-top shit we have encountered on this one and the rest..
This CSO/Detention system serves the Western interceptor sewer and is quite possibly one of the biggest combined sewer overflows I have seen to date
The traversable section of sewer here is over 400m end to end with a couple of chambers including a remote controlled Penstock
A good 70% of the space serves as an in-line storm tank including a non screened CSO to relieve the sewer upstream of the Wwtw
We originally decided to leave this one until last, having already scoured the rough area for 'safe' lids there appeared to be none anywhere you would expect them to be, despite 2 or 3 frustrating recces
We always knew there was access in the streets, and hence the main reason we stuck it on a back burner
One bright day in the middle of the night, we were out to continue another piece we have been working on when we decided to chance a lid, no sooner had Squiz0r unfolded the barriers I was down
Once inside we reverse engineered a safe lid for follow up visits, good job as the first round of pics were a bit hit and miss due to tripod fail... (STFU Squiz with regards to that one, before you start!) :
Since the early 90's much of the City's sewers have had a major revamp due to flood alleviation and a rapid increase in population resulting in extra capacity
Much of the older principal brick sewers (still visible here and there) have been replaced during rehabilitation works by more sizeable swagged out concrete structures which need to be seen to be appreciated!
In 1994 lock stock the fucking lot gained the accolade of "Institute of Civil Engineering Yorkshire Association Award" for excellence in the concept, design and execution of Civil Engineering Works
And it's fair to say having spent the last 5 years mooching about below ground here on and off I can certainly vouch for that one ^
Sure the brick stuff in Manc & Lon is spectacular in it's own right, but the modern day trunks here are quite something else
^ read into that lot what you will, either way it's a lot of shit
I'll continue with a bunch of snaps from a couple of visits to this hooj and by far the largest of the final CSO's which serves the Western interceptor before it hits the final outfall to Esholt Wwtw...
Man in Hole
Western Interceptor
First we headed downstream; along the way a smaller trunk run-off joins
..the d/s section is eventually truncated by a Penstock, located beyond the CSO
We managed to locate a suitable lid on a follow up visit for a closer look at the Penstock Chamber
..The larger of which is hidden behind the gantry
Beyond which the outgoing sewer exits via a non traversable 6ft RCP
Here the u/s limit sees the incoming sewer enter via a 8ft RBP and drop into a 4ft channel
Eventually it widens ahead of the main storm overflow
Somewhere inbetween the u/s .. d/s limit is the detention/overflow weir which serves the sewer at capacity
Beyond the weir a split overflow which eventually outfalls into the Bradford Beck via 2 5ft RCP's
Around 200m both pipes outfall into the beck; it's full on insanitry here so expect nothing less..
And lastly the twin outfall into the Beck
A West is East swr special
[video=youtube_share;v3irTrv2BRY]http://youtu.be/v3irTrv2BRY[/video]