The Elan Valley dams
James Mansergh, dambuilder
James Mansergh's detailed report on the area upon which the huge project was based included an impressive scale relief model of the watershed of the rivers Elan and Claerwen which he had built with the help of his son.
Relief model of
the Elan and Claerwen
watershed made
in 1891
(right)
James Mansergh FRS,
former President
of the Institute
of Civil Engineers
(far right)
kind permission of
Radnorshire Museum,
Llandrindod Wells
The model is of particular interest in that it included the
three dams originally proposed for the Claerwen Valley, seen
extending to the left. Of these, only the base of the dam at
Dol-y-Mynach (bottom right of
the model above) was destined to be built. The valley of
the River Elan runs vertically on the right of the model, and
the reservoirs shown were all created by the scheme.
See the sketch map of the dams and reservoirs
today for comparison with the original scheme.
Another view of the Elan Valley taken from an early
souvenir postcard is shown (right), with the picture captioned
"Before Waterworks Scheme".
Roads like this one which followed the course of the river along
the floor of the valley were later replaced by new roads and
railway tracks cut into the valley sides above the top water
level of the reservoirs, and access roads were also built along
the top of two of the new dams.
