Beneath the streets of Sheffield city centre lies a huge space known to many as ‘Megatron’, it is one section of a long string of underground tunnels that carry the unwanted waterways of the city out of sight and out of mind.
Since before the thirteenth century, the river Sheaf was a source of power that drove the industries of Sheffield. It’s power was exploited to drive mills that produced anything from paper to cutlery and during it’s ‘working life’ the river was cultivated and diverted to suit the needs of the local industries, at the cost of the natural wildlife. The river and it’s tributaries eventually became heavily polluted with the industrial revolution and remained that way for many decades.
With the construction of Sheffield Midland station in the 1860’s the Midland Railway company purchased the rights to the river so they could build the railway station over it’s course. The river was then enclosed in a culvert right up to it’s confluence with the river Don, roughly 1.25 Km away beside the Blonk Street Bridge.
A great variety of construction techniques used in the culvert demonstrate Sheffield’s dynamic history. As the town expanded, the need for extra land for building space meant the river became almost completely covered from view as it passed through the heart of the city. The variety is certainly interesting to today’s explorers and the site is visited regularly. One section is known as ‘Cathedral Chamber’, or ‘Megatron’; the names hinting at it’s grand scale. As you reach the river there is little to suggest it is much more than a wide, but gentle stream most of the time, but when in flood, huge quantities of water can pass through it’s channel and the railway station above can be prone to flooding.
Entering the river it was nice to see it has been cleaned up over the years and is now supporting quite a few trout, and rare native crayfish. There are many routes to choose from, as other culverted tributaries like the Porter Brook join the waterway. Upon reaching the area of the station, the channel is split into three as the river pours over a small, stepped weir. This triple arched construction varies, with areas made of cleanly cut stone, brick, and rough stone, all oozing Victorian engineering styles.
For the next 250m the river only really flows along one arched channel at a time leaving the two others almost dry, but rags and other debris snagged high up in the stonework show this is not a place to be in wet weather. Large amounts of brick and stone rubble are strewn across the river bed which is difficult to walk upon.The culvert opens out into fresh air just once before it reaches the River Don, with the street lights of the city pouring down into the cutting. A mere 20 metres on and you are faced with a slightly taller version of the same triple arched construction which leads down to our goal, the infamous ‘Megatron’.
For me, there’s something special about the sounds inside a culvert. The gentle trickles and plops in the water that echo from the walls, the squeak of bats as they fly past your head, and the occasional noise of a rat as it scurries across the floor. The aroma of sewage inside the main chamber also reveals that you have to watch out for the odd bit of poop, but still there are plenty of trout, the occasional white clawed crayfish and thousands of Bullheads/Miller’s Thumb; the presence of which shows that the water quality has improved greatly over the years.