- River Rheidol
The River Rheidol is a river of
mid Wales . The Rheidol catchment has an area of 246 square kilometres and an average rainfall of 1760 mm of which 1272 translates into river flow. It has an average flow of 9.657 m³/s at Llanbadarn Fawr and a maximum recorded flow of 145.285 m³/s on17 December 1965 . Note that the flow is regulated by a hydroelectric power scheme atCwm Rheidol .Geography and geology
The Rheidol rises in the headwaters of the
Nant y Moch reservoir on the western flanks ofPlynlimon and then flows south through the village of Ponterwyd on the mainAberystwyth toRhayader road. Continuing south-westwards, largely through ancient Welsh Oak woodlands in an increasingly deep valley the Rheidol joins with theAfon Mynach and veers westwards, the direction in which it continues for most of the rest of its course. At its confluence with the Mynach, it descends one of the most spectacularwaterfall s in Wales at Pontarfynach (Devil's Bridge). Below these waterfalls, the river passes the abandoned workings of theCwm Rheidol lead mine. This mine, together with numerous other metal mines in the valley, has been a source of extreme metal pollution of the river right down to the sea. Even when the mine was closed, a major blowout of water contained in anadit in the late 1960s coloured the whole river anochre orange colour and greatly added to the concentrations of lead and zinc in the river. Management of the waters still draining from the mine is by the use ofconstructed wetland s. Previous management includes a limestone filter bed, installed in the 1960's, which is now redundant. The filter bed is still in place and can be seen from the road. The remainder of the meandering course of the river is through an ever-widening valley before discharging to the sea through AberystwythEnvironment
The catchment of the Rheidol is dominated by the western maritime exposure of this part of
Wales . Rainfall levels are high and ecosystems reflect both high rainfall and the acidic nature of the underlying rocks. Upland "Molinia " spp. grassland is common growing on deep deposits ofpeat . Within the valleys, dense and ancient oak forests with rich understoreys offern s,moss es andlichen s are common. In the valley bottom, glacial and alluvial deposits have been worked by man into a relatively low intensive agriculture.Economy and the human influence
Metal mining dominated the economy of the Rheidol valley for many centuries. Mining has now been replaced by
farm ing (beef , dairy andsheep ),forest ry andtourism .There are a number of tourist attractions in the Rheidol valley. These include the Devil's Bridge waterfalls where three bridges, each built over the previous, span the top of a most spectacular waterfall.
Between Devil's Bridge and Aberystwyth runs a narrow-gauge steam railway - the
Vale of Rheidol Railway . This was originally built to ship metal ore from the mines but now provides a very popular tourist route into the top end of the Rheidol valley.
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