Mumbles Head Drainage Tunnels used during WW2
Access Tunnels
Few people realise what lies behind the doors protecting the Tunnels at Mumbles Head
Entrance to the 'Fan Chamber,' near the Pier Road Cutting, May 2022
THE TUNNELS WERE USED DURING WORLD WAR TWO
At the outbreak of war in 1939, the tunnels took on another role when the Brangwyn Panels from the Guildhall, all the best porcelain and glass from The Glyn Vivian Art Gallery, as well as other precious items from Swansea Museum (formerly The Royal Institution of South Wales) were removed to a place of safety, using several of the sewage scheme access tunnels and other locations. Thomas Knibbs, the caretaker of the Glyn Vivian Art Gallery, said that he would check these tunnels every week and in all that time nothing was ever damaged.
Workmen at the tunnel entrance, 1935. Photo: M.A. Clare, OHA Archive
"It was very clean inside!"
After the official opening and before sewage use began the works were open to the general public for one week. Visitors to the 4 storage tanks inside Mumbles Hill walked into the tanks and saw some of the 10 million bricks used in the sewer construction. "I think the bricks were white and it was very clean," recalls one Mumbles resident from her visit as a child. The Evening Post described the tanks (each 1995 feet long, 16 feet wide and over 10 feet high and lined with bricks) as "stretching into infinity ... electric lights twinkling smaller and smaller into the distance ..." (OHA Archive 'Down The Drain' ).
Bracelet Bay
During routine maintenance, it was possible to have a glimpse into the access tunnel for the 'Penstock Chambers Control Room' situated on the eastern side of Bracelet Bay.
Sheila Davies comented on Facebook - 'The sewage works was through a large green door in the side of the the cliff, as a nurse tutor I had to take student nurses on a visit to see how the sewage was dealt with before being discharged some distance out at sea.'
The Mumbles Outfall, Bracelet Bay, March 2022
When completed the doors were wooden and smart, but now the entrance is looking a little battered.
The Attendant's House
Earlier
Later
This Mumbles bungalow, pictured soon after being built in the mid 1930s, had a secret in the cellar. Built into the cliff face, it housed the village's sewage pumping station, which used to contain the holding tanks, used for the collection of all the sewage for Swansea. When the tide was ebbing, the sewage was pumped out so that the tide could wash it down the channel.
over the screening chamber
By J.R.Heath. M.Inst.M. &.Cy.E. Chief Engineer.
Swansea Main Drainage Scheme, March 1936
Screening Chamber, under the bungalow
"Tunnels stretching into infinity":
The tunnels in Mumbles Hill were blasted out of dense limestone, so that at their deepest point they lay over 200 feet below the surface of the hill. A central ventilation shaft was dug first and then each section of the 4 tunnels was worked upon so that 8 stretches of tunnel were constructed simultaneously. Approximately 75,000 cubic yards of rock were excavated from the tunnels. The work was arduous and not without dangers. Two workmen were killed in 1932 and buildings in Southend were damaged by falling blasted rocks. (OHA Archive 'Down The Drain' ).
Storage Tanks
A general view of Mumbles Hill, under which the storage tanks are being constructed
View of inlet end of one Storage Tank
Disruption at Bracelet Bay and Mumbles Head:
A series of photographs taken in 1935 by M.A. Clare illustrate just how Bracelet Bay had become unrecognisable. The Evening Post described it as "one huge silver grey spoil bank of excavated limestone, down which shutes run and over which electric lights glitter. ... It is possible to see 50 yards or so down one of the tunnels, and, when it is aglow with electric lamps, it is [like] Aladdin's Cave, from whose inky depths comes the pulsating of a hidden engine."
(OHA Archive 'Down The Drain' )
Bracelet Bay Before and After
After
By 1936, large quantities of stone had been mined to creat the various tunnels for the scheme. Most was used to create the popular Bracelet Bay car park (seen below) and some stone infilled the old Iron Mine cutting on the Hill, from above Knab Rock.
Before
This pre 1920s photo shows Bracelet Common, which stretched from the beach, over Mumbles Hill, is seen before the 'Drainage' scheme created the car-park.
Work in progress
The twin sea outfall pipes at Mumbles Head, 1936
Sea Outfall under construction at Mumbles Head, c.1935 (and below) -
Sea Outfall under construction, Mumbles Head, c.1935
Mumbles Lighthouse - Later
Mumbles Lighthouse, taken from out to sea at low tide, which reveals the top of the sewer pipe, as well as the pillars on which run the railway lines for the crane memtioned earlier. Photo: Ronald Studden.
Swansea Main Dranage Scheme Key Plan
All the plans are reproduced in a larger format - Larger photos & plans file >
The full details are revealed -: The Opening of Swansea Main Drainage Scheme >
From Clydach to Brynmill - Contract No. 9
From Brynmill to Mumbles Head - Contract No. 8
Key Plan
Sea Outfall - One
Sea Outfall
Sea Outfall - Two
Access Gallery
Sea Outfall - Three
Elevation of Attendant's House
Plan - One
Sea Outfall
Plan- Two
Plan- Three
Acknowledgments
The research and assistance is greatly appreciated from:
Main Drainage Works, a booklet, published by the County Borough of Swansea upon the opening of the scheme, on Thursday 30th July 1936.
Oystermouth Historical Association Archive, Leaflet 7, 'Down The Drain'.
South Wales Evening Post, 1930-36; SWANSEA - Dŵr Cymru Welsh Water. Swansea Reference Library; Kate Jones 2003 and 2007; William Welham; The Family of M.A. Clare; R.H. Clare; Carol Powell; David Spooner; Betty Sivertsen and Stuart Bishop.