RO H2O

Tim Bazeley has very kindly provided me with an article on the creation of the reverse osmosis water supply at Toddington, but before we get to that, there are a couple of important bits of news to pass on.  Firstly the second of our guest gala locomotives has turned up.  BR standard 4MT, 80072 arrived two days earlier than anticipated on Wednesday.  I shall hopefully have a moment or two to inspect her and take a few photos tomorrow, expect more of her in the next blog article.  Secondly Cheltenham went to Cheltenham for the first time ever yesterday to meet the staff and pupils of Cheltenham College.  This was 79 years late!   The crew for the occasion, Andy Beale and Paul Richardson have both been given detentions for their tardiness.  Rumour has it that the headmaster was overheard saying that he very much regretted the fact that it wasn't acceptable to use corporal punishment any more however both Andy & Paul are believed to have resorted to the time honoured technique of stuffing exercise books down the backs of their trousers just in case.  A fuller (and probably rather more accurate) description of the event can be found on the main GWSR website, on the Cheltenham News website as well as the Gloucestershire Echo:

Speaking of Paul Richardson & Cheltenham, volunteers (who hold work permits) are still required to help man the crossing during the gala.If you can possibly spare any time, then please contact Paul via email at pl.richardson1@googlemail.com

Finally, many thanks indeed to Tim Bazeley for providing the following article on the construction of the reverse osmosis water treatment plant at Toddington:

Toddington's Water Supply

Toddington’s locomotive water supply system has been reinstated and locos are once again able to take on water from cranes on both platforms, fed by the original cast iron supply pipes from a refurbished 12,000 gallon tank.

The system is supplied from the main in the centre of the Stow Road via a modern high-pressure plastic pipe running through an existing access pit in the garden of No 1, Station Cottages (which contains shut off valves and a water meter) to a new access pit under the 12,000 gallon tank and a fire hydrant connection. From this pit a new pipe laid in a trench behind platform two feeds a fresh-water carriage washing point, a supply point for the adjoining field (for campers) and a new water treatment plant located in the old acetylene hut just beyond the 4,000 gallon parachute tank.

The work that has been done inside the old acetylene hut deserves a story in itself. It now contains an ultra-modern water treatment plant that softens and de-ionises the incoming mains water and then pumps it back (via the same trench as the incoming water) to the parachute and the main tanks.

The level of the water in the main tank is monitored by an electronic float switch that activates the water treatment plant as and when required. The treated water flows through two gigantic ball float valves, mounted on the original cast iron water supply pipe, that serve as an emergency back-up in the unlikely event of any form of water treatment plant failure.

In tandem with laying the new pipes to and from the treatment hut, a third pipe was installed, tee'd-off near to the existing parachute tank, to supply a source of treated water (for filling boilers after washouts and annual inspections) which temporarily terminates just past the treatment hut. In the autumn, this trench and piping will be continued down behind the signal box and then the pipe will cross under the track through an existing conduit to supply the re-located parachute tank, which will be positioned in front of the locomotive sheds in order to top up incoming and outgoing locos. The parachute tank will be fitted with a simple float valve so that it is automatically filled with treated water from the main tank. (In its present position, the parachute tank is temporarily filled by manual switching from the treatment hut, as and when required).

To render the whole system fully automatic and self-contained, an armoured electrical mains cable was laid in the trench between the treatment hut and the waiting room on platform two, together with a flexible conduit between the treatment hut and the base of the main tank, teed-off into the waiting room. The hut is thus fed with mains electricity; the vertical main feed and supply water pipes into the tank are kept frost-free by heavy insulation (and trace heating from the waiting room); and the water level in the tank is remotely controlled from the treatment hut by an electronic level switch mounted inside the main tank. The original electrical and water supplies to the treatment hut have been disconnected and are now part of ancient history!

So what was involved? A lot of hard work by dedicated volunteers, backed up by a steam railway company that is doing its damnedest to ensure that this line will be second to none; both in the quality of its operation and its customers enjoyment.

To start with, we were fortunate in that most of the underground supply and drainage pipework was still in situ and capable of being reused. The water cranes themselves, and all of their control gear and pipework were long gone and had to be found elsewhere and restored before being refitted into their original pits.

The 12,000 gallon tank had been removed many years ago and a replacement had to be found elsewhere and refurbished, along with all of its heavy steel supports and cross braces. Under the tank, the original cast iron supply pipes feeding the two cranes were still in situ but the main shut-off valves were broken and had to be replaced and the inlet flange for the main water pipe from the tank had to be relocated.

Needless to say, the modern shut-off valves were not interchangeable with the originals; however some ingenious machining by one of our many skilled volunteers provided us with adapter plates that enabled the existing pipe work to be reinstalled in its original position.

A fire hydrant connection and three brick pits giving access to all of the control valves have been installed and the whole area underneath the tank has been leveled and graveled. The main vertical input and delivery pipes have been boxed in (as were the originals) and are heavily insulated and fitted with trace heating to protect against freezing. It is hoped sometime in the near future to replace the wire fence next to the field with authentic spear fencing to match the rest of the station surrounds.

To summarise what’s been done, we now have fully treated water for our locos available in quantity from water cranes in their original positions on both platforms, fed from a large tank that is indistinguishable from its predecessor. We have two ultra-modern water softening and de-ionising plants that allow us to fill the 12,000 and 4,000 gallon tanks 24 hours a day, 7 days a week, alternating weekly between plants and using both together in periods of peak demand!