Located near Bury this CSO provides an overflow for one of the town's main sewers before it travels under the Irwell on its way to the treatment works.

This little culvert, found near Droylsden, is around 350m long and built of stone and brick. I went in from the outfall, after a stoopy 4f beginning it opened up slightly and allowed a more comfortable walk.

Drainers from all over the world converged in London for this year's International Drain Meet, it was a quality evening packing more people in a drain than I've ever seen before. It was a pleasure to both see old faces and meet the rest of the community, big shouts to everyone who went!

When first stepping foot in Crypt one could be forgiven to thinking it is an anomaly in the system. Seemingly the purpose of this chamber is to act merely as confluence between two egg shaped sewers, the largest being the Putney Extension.

This culvert is found on the upper reaches of the River Irk. Unlike the massive downstream culverts like Optimus Prime, the river here demands only a small conduit.

A metal walkway forms an L shape around a chamber, a large 20ft trunk sewer flows beneath. Two sets of well maintained machinery allow massive penstocks to be closed to send the flow down another route.

Optimus Prime is a large culvert that takes the River Irk underground for it's final stretch before the outfall into the Irwell. I met up with Nckt and Jim Gillette to have a look.