* For information on the in-situ conservation costs (or repair costs) see page 11 and Appendices F and G in the Feasibility Study (Revision F) prepared by Paul Latham of The Regeneration Practice. The more expensive and less conservative method of off-site conservation for the so-called ‘retention’ of the gasholders would, according to St William, cost “in the region of £10m per gasholder” (LBTH response to Main Matter 10 August 2018).
Actual costs for the development at Bethnal Green have still to be worked out and much depends on Craddy Pitchers Ltd report on the condition of the two guide frames. They are consulting engineers (previously involved in the off-site conservation of gasholder guide frames at King’s Cross and currently at Kennington), and EEWG fears that their forthcoming report for Bethnal Green will serve as a justification for the unnecessary and expensive off-site conservation of the No.5 guide frame and the demolition of the No.2 guide frame.
The relatively low costs for in-situ conservation and related works for a ‘gasholder park’ inside the No.2 guide frame (together with the higher costs for in-situ conservation of the No.5 guide frame and related works for blocks of flats inside the No.5 guide frame) should be covered by market sales of flats in the blocks built inside the No.5 guide frame.
The cross-sectional drawing shows the three main parts of a traditional gasholder (in-ground tank, bell and guide frame, which are mentioned in the petition and the reasons); and indicates the up and down movements of the bell as it filled with gas and emptied as the gas was forced and drawn into the gas mains.
There were two adjacent vertical pipes (between the in-ground tank wall and the lowered bell) with open ends above the level of the water in the in-ground tank. Gas was pumped via the inlet pipe into the domed part of the bell’s inner telescopic lift, causing the lift to rise; and the stored gas passed into the gas mains via the outlet pipe.
The up and down movements of the bell were guided and supported by the guide frame with its guide rails on the insides of the columns (or the standards in a lattice girder guide frame, like the No. 5 at Bethnal Green). The rim of the domed part of the bell’s inner telescopic lift had roller carriages with double-flanged rollers which ran up and down the guide rails; and there were flanged rollers on the sides of the lifts below the carriage rollers.
Tom Ridge
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