Diocletian, Bolton

Ojay/ViralEye...

Diocletian is essentially a set up of 2 x non-screened/double sided weir CSO's linked to an off-line detention tank, a spill culvert and a pumping station
At absolute capacity, spill flows are discharged to the River Croal, looking at the set up I imagine this would only occur a handful of times annually
The rest of the time, the unscreened spill flows are returned via the pumping station back to the nearby sewer

I originally got around to looking at this almost a year ago now having once looked at the grilled outfall and realising that unless I was able to fold myself like the latest Apple iPhone it wasn't happening!

concreteJungle eventually brought this epic monster to the surface; one of the biggest tanks I've seen to-date.

Even the mighty 'In My Sights' doesn't touch this and that was some ridiculous set up!

I pulled my finger out one night with ViralEye, having already worked out a more suitable way in

That said, we went for another look recently and UU have since taken care of access :(

The pumping station is already belled up and heavily fortified as it is.

Hopefully a few shonky pics might help you better visualise the place..

A 6m ladder dropped us into a 4m wide segmental drop shaft and into the spill culvert below

The 5'4" RCP to the left eventually outfalls to the Croal via a stagnant, semi submerged grilled outfall.

Following the spill culvert upstream ^ right is initially a 4ft stoopy affair, before a quick U-turn carries the intrepid explorer a good 180m through barely a 5ft segmental RCP.

Eventually a junction; A number of small surface water drains connect upstream of the CSO, you can see a steady trickle exit via this 3ft pipe.

The stepped entrance on the left, leading to one of the afore mentioned non-screened CSO's.

This smaller upstream CSO serves a 4ft sewer which in turn runs through the larger downstream CSO.

(See further below) where another trunk sewer connects.

Further downstream, A.N Other non-screened CSO is the last line of defence before the tank was installed.

A rather ludicrous manhole drops you into this one.

Try traversing a thigh deep mud bank with worms chomping on your nether regions for a look in a sewer which incoming is 4ft and outgoing less than 3ft for a laugh, not my idea of fun.

The insane pipe set-up (which is actually the overflow) draped in toilet peripherals, is just about recognisable in the above pic.. this leads to the shit tank.

A small penstock can be manually lowered from the compound above ground when required.

On this occasion I didn't bother to jump into the sewer, I was actually not keen on hanging about in this one so a quick shot and out.

I was more interested in the tank, back down the RCP and a short crawl through a relief valve exits into a 10,000 m³ shit tank.

Some serious arse broth this

Just below the top gantry, you can see the overflow from the above CSO; flow is carried down into the tank via a twin vortex.

Excess spill flows are conveyed over this giant concrete lip.

Here you can just about make out a solitary turd, just out of reach of the very same piece of toilet paper that accompanied it down here.

What I can really only describe as a stairway to shyte allows you to inspect the tank further.

It's massive and no matter how many lumen's you throw at it, it just swallows them up.

I stood on the precipice of shyte, getting as near to the soup as I possibly could, it was bubbling away nicely.

I'd be interested to see how much deeper this thing is once it's pumped, as looking at the staircase that disappears into the gloom it could be some distance.

It was good to finally see inside here and getting around to sorting through the pics finally..