River Rheidol
Encyclopedia
The River Rheidol is a river
of mid Wales
. The Rheidol catchment has an area of 100 square miles (259 km²) and an average rainfall of 40 inches (1,016 mm).
reservoir on the western flanks of Plynlimon
and then flows south through the village of Ponterwyd on the main Aberystwyth
to Rhayader
road. Continuing south-westwards, largely through Welsh Oak ancient woodland
s in an increasingly deep valley the Rheidol joins with the Afon 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 spectacular waterfall
s in Wales at Pontarfynach (Devil's Bridge). Below these waterfalls, the river passes the abandoned workings of the Cwm 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 an adit
in the late 1960s coloured the whole river an ochre
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 of constructed wetland
s. Previous management includes a limestone filter bed, installed in the 1960s, which is now redundant. The filter bed is still in place and can be seen from the road. The remainder of the meander
ing course of the river is through an ever-widening valley before discharging to the sea through Aberystwyth
.
. Rainfall levels are high and ecosystem
s reflect both high rainfall and the acidic nature of the underlying rocks. Combined with the acid mine drainage
from abandoned silver/ lead mines that sit within the catchment (the area around Aberystwyth contains 38 of the 50 worst polluting metal mines in Wales), the river regularly broke EEC
pollution limits (as of 1991) for heavy-metal contamination such as zinc
.
Upland Molinia
spp. grassland is common growing on deep deposits of peat
. Within the valleys, dense and ancient oak forests with rich understoreys of fern
s, moss
es and lichen
s are common. In the valley bottom, glacial and alluvial deposits have been worked by man into a relatively low intensive agriculture.
ing (beef
, dairy
and sheep), forest
ry and tourism
.
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.
River
A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...
of mid Wales
Mid Wales
Mid Wales is the name given to the central region of Wales. The Mid Wales Regional Committee of the National Assembly for Wales covered the counties of Ceredigion and Powys and the area of Gwynedd that had previously been the district of Meirionydd. A similar definition is used by the BBC...
. The Rheidol catchment has an area of 100 square miles (259 km²) and an average rainfall of 40 inches (1,016 mm).
Geography and geology
The Rheidol rises in the headwaters of the Nant y MochNant y Moch
Nant-y-moch Reservoir is situated in the Cambrian Mountains in northern Ceredigion, Wales. The reservoir which flooded a part of the valley of the River Rheidol and its headwaters derives its name from a stream, the Nant-y-moch , which formerly flowed into the River Rheidol at this spot. The dam...
reservoir on the western flanks of Plynlimon
Plynlimon
Plynlimon is the highest point of the Cambrian Mountains in Wales, and the highest point in Mid Wales. It is a massif that dominates the countryside of northern Ceredigion....
and then flows south through the village of Ponterwyd on the main Aberystwyth
Aberystwyth
Aberystwyth is a historic market town, administrative centre and holiday resort within Ceredigion, Wales. Often colloquially known as Aber, it is located at the confluence of the rivers Ystwyth and Rheidol....
to Rhayader
Rhayader
Rhayader is a market town and community in Powys, Mid Wales. It has a population of 2,075, and is the first town on the banks of the River Wye, from its source on the Plynlimon range of the Cambrian Mountains....
road. Continuing south-westwards, largely through Welsh Oak ancient woodland
Ancient woodland
Ancient woodland is a term used in the United Kingdom to refer specifically to woodland that has existed continuously since 1600 or before in England and Wales . Before those dates, planting of new woodland was uncommon, so a wood present in 1600 was likely to have developed naturally...
s in an increasingly deep valley the Rheidol joins with the Afon Mynach
Afon Mynach
The Afon Mynach is a small river in Ceredigion, Wales.Its source is at the meeting of two smaller rivers, the Nant Rhuddnant and the Afon Merin...
and veers westwards, the direction in which it continues for most of the rest of its course. At its confluence
Confluence
Confluence, in geography, describes the meeting of two or more bodies of water.Confluence may also refer to:* Confluence , a property of term rewriting systems...
with the Mynach, it descends one of the most spectacular waterfall
Waterfall
A waterfall is a place where flowing water rapidly drops in elevation as it flows over a steep region or a cliff.-Formation:Waterfalls are commonly formed when a river is young. At these times the channel is often narrow and deep. When the river courses over resistant bedrock, erosion happens...
s in Wales at Pontarfynach (Devil's Bridge). Below these waterfalls, the river passes the abandoned workings of the Cwm Rheidol lead
Lead
Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...
mine. This mine, together with numerous other metal mines
Mining in Wales
Mining in Wales provided a significant source of income to the economy of Wales throughout the nineteenth century and early twentieth century....
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 an adit
Adit
An adit is an entrance to an underground mine which is horizontal or nearly horizontal, by which the mine can be entered, drained of water, and ventilated.-Construction:...
in the late 1960s coloured the whole river an ochre
Ochre
Ochre is the term for both a golden-yellow or light yellow brown color and for a form of earth pigment which produces the color. The pigment can also be used to create a reddish tint known as "red ochre". The more rarely used terms "purple ochre" and "brown ochre" also exist for variant hues...
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 of constructed wetland
Constructed wetland
A constructed wetland or wetpark is an artificial wetland, marsh or swamp created as a new or restored habitat for native and migratory wildlife, for anthropogenic discharge such as wastewater, stormwater runoff, or sewage treatment, for land reclamation after mining, refineries, or other...
s. Previous management includes a limestone filter bed, installed in the 1960s, which is now redundant. The filter bed is still in place and can be seen from the road. The remainder of the meander
Meander
A meander in general is a bend in a sinuous watercourse. A meander is formed when the moving water in a stream erodes the outer banks and widens its valley. A stream of any volume may assume a meandering course, alternately eroding sediments from the outside of a bend and depositing them on the...
ing course of the river is through an ever-widening valley before discharging to the sea through Aberystwyth
Aberystwyth
Aberystwyth is a historic market town, administrative centre and holiday resort within Ceredigion, Wales. Often colloquially known as Aber, it is located at the confluence of the rivers Ystwyth and Rheidol....
.
Environment
The catchment of the Rheidol is dominated by the western maritime exposure of this part of WalesWales
Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...
. Rainfall levels are high and ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
s reflect both high rainfall and the acidic nature of the underlying rocks. Combined with the acid mine drainage
Acid mine drainage
Acid mine drainage , or acid rock drainage , refers to the outflow of acidic water from metal mines or coal mines. However, other areas where the earth has been disturbed may also contribute acid rock drainage to the environment...
from abandoned silver/ lead mines that sit within the catchment (the area around Aberystwyth contains 38 of the 50 worst polluting metal mines in Wales), the river regularly broke EEC
European Economic Community
The European Economic Community The European Economic Community (EEC) The European Economic Community (EEC) (also known as the Common Market in the English-speaking world, renamed the European Community (EC) in 1993The information in this article primarily covers the EEC's time as an independent...
pollution limits (as of 1991) for heavy-metal contamination such as zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
.
Upland Molinia
Molinia
Molinia is a genus of two species of grasses. The genus is named after Juan Ignacio Molina, a 19th century naturalist and scientist from Chile.Species*Molinia caerulea . Northern Europe and Asia....
spp. grassland is common growing on deep deposits of peat
Peat
Peat is an accumulation of partially decayed vegetation matter or histosol. Peat forms in wetland bogs, moors, muskegs, pocosins, mires, and peat swamp forests. Peat is harvested as an important source of fuel in certain parts of the world...
. Within the valleys, dense and ancient oak forests with rich understoreys of fern
Fern
A fern is any one of a group of about 12,000 species of plants belonging to the botanical group known as Pteridophyta. Unlike mosses, they have xylem and phloem . They have stems, leaves, and roots like other vascular plants...
s, moss
Moss
Mosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...
es and lichen
Lichen
Lichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...
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 farmFarm
A farm is an area of land, or, for aquaculture, lake, river or sea, including various structures, devoted primarily to the practice of producing and managing food , fibres and, increasingly, fuel. It is the basic production facility in food production. Farms may be owned and operated by a single...
ing (beef
Beef
Beef is the culinary name for meat from bovines, especially domestic cattle. Beef can be harvested from cows, bulls, heifers or steers. It is one of the principal meats used in the cuisine of the Middle East , Australia, Argentina, Brazil, Europe and the United States, and is also important in...
, dairy
Dairy cattle
Dairy cattle are cattle cows bred for the ability to produce large quantities of milk, from which dairy products are made. Dairy cows generally are of the species Bos taurus....
and sheep), forest
Forest
A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...
ry and tourism
Tourism
Tourism is travel for recreational, leisure or business purposes. The World Tourism Organization defines tourists as people "traveling to and staying in places outside their usual environment for not more than one consecutive year for leisure, business and other purposes".Tourism has become a...
.
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
Vale of Rheidol Railway
The Vale of Rheidol Railway is a narrow-gauge gauge heritage railway that runs for between Aberystwyth and Devil's Bridge in the county of Ceredigion, Wales...
. 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.