THE CONSTRUCTION OF THE GRWYNE FAWR WATERWORKS (1913-1928): A RELIC AT CROSSKEYS by Graham Osborne During the latter half of the nineteenth century, the population of the western part of what was then Monmouthshire increased enormously. The development of iron and steel manufacture and of coal mining, transformed what had once been a peaceful rural area. With an increase in population, problems soon arose with water supplies. The supplies from wells and springs, adequate for the much smaller, earlier populations, now became quite inadequate. Moreover, pollution of these sources sometimes posed serious problems. Outbreaks of waterborne diseases such as typhoid were not uncommon. At the end of the century, the body responsible for the provision of water supplies in the Western Valleys was the Western Valleys Gas and Water Co. In the lower Western Valleys, following the development of 'colliery' villages at Wattsville and at Newtown, Crosskeys, this company constructed in 1894 a small reservoir in the Nant-y-draenog valley near Cwmfelinfach. This reservoir supplied the above places and the pipeline was continued to Risca. But by about 1900 the problem of water shortages in the Western Valleys was becoming acute. In those days, the Local Authority, i.e. Monmouthshire County Council was responsible for water supply. In 1906 it commissioned an engineer to look at these problems and to suggest a solution. Problems were worst in the western parts of the county. The additional complication here was that villages around, for instance, Abertillery (1000-feet above sea level), stood at quite high altitudes. Any impounding reservoir, to deliver water by gravity feed, would need to be situated on substantially higher ground. No such site was to be found in Monmouthshire. But there was such a site (above 1600- feet) at the head of the Grwyne Fawr valley, in the Black Mountains, in Breconshire. In that excellent little book, Stone and Stream in the Black Mountains, published in 1975, the late Rev. David Tipper tells the epic story of the struggle to build a reservoir in this remote spot. Completed in 1928, this reservoir still supplies the major water requirements of places in the Western Valleys. The story starts in 1908. In that year Monmouthshire County Council sponsored a Parliamentary Bill which would have enabled them to take water from the Grwyne Fawr valley. But, at that time, such a bill was quite without precedent. Predictably