The Old Roundhouse - Yr Hen Garchar

Municipal History of Llanidloes by E. Horsfall Turner p 240 and p 211

1902 Llanidloes Town Water Supply

Nant y Geifr reservoir providing the water supply to Llanidloes, built by John Jones Meredith in 1902.

View towards Llanidloes from earth dam of reservoir

In 1902 John Jones Meredith created a town water supply with a reservoir at Nant y Geifr (about 2 miles away) and the piped supply was brought into the town at Highgate Street, with the rented Roundhouse becoming the Filter House. The middle cell wall was removed and the ceiling above, and in the space a large iron filter tank was built on two supporting brick pillars (now under the kitchen/dining floors). The top of the tank could be raised for filter cleaning by a block and tackle equipment hanging from old railway lines resting on the large wooden beams and embedded in the stone walls of the bedrooms. When digging down into the floor of the cell area, Alison found the cast iron pipe coming in from the reservoir and the smashed end of the pipe going into the town, which is now mainly hidden under the kitchen floor.

When digging out the cell area, the first foot of depth was obviously river gravel but after that the material was very lightweight. Microscopic examination showed that this was the filtrate - a mixture of sand, charcoal and heather, the usual filtrate in 1900 - allowed to fill the ground after the tank was demolished.

(The railway lines are now outside in the parking area. The lower, lighter sections almost certainly came from the Llanidloes-Newtown railway of 1859. The upper rails are heavier and came from the Dowlais steelworks in South Wales in 1904. The stamp on the rail also includes RSBR, indicating that they were from the Rhondda and Swansea Bay Railway.)