The River Rhondda (Welsh: Afon Rhondda) is a river in south-east Wales which has two major tributaries; the Rhondda Fawr (English: Large Rhondda) and the Rhondda Fach (English: Little Rhondda). Welsh redirects here, and this article describes the Welsh language. ... This article is about the country. ... The English language is a West Germanic language that originates in England. ... The River Rhondda (Welsh: ) is a river in south-east Wales which has two major tributaries; the Rhondda Fawr (English: ) and the Rhondda Fach (English: ). Despite their names, both tributaries are about the same length. ... The English language is a West Germanic language that originates in England. ...

Despite their names, both tributaries are about the same length. Both valleys are typical U shaped glaciated valleys in carboniferous sandstones and coal measures. The whole form of the river and its surrounding urbanisation has been dominated by coal and the mining communities that grew up to exploit the rich coal seams. Much of the valley has suffered severe subsidence because of the removal of coal from underneath the valley floor. The houses and streets have subsided with the result that river levels are, in parts , higher than the surrounding houses. In order to contain the river and prevent flooding, walls have been built, sometimes across the ends of streets - these are known as The Rhondda walls The Carboniferous is a major division of the geologic timescale that extends from the end of the Devonian period, about 359. ... Red sandstone interior of Lower Antelope Canyon, Arizona, worn smooth due to erosion by flash flooding over millions of years Sandstone is a sedimentary rock composed mainly of sand-size mineral or rock grains. ... Coal Coal (IPA: ) is a fossil fuel extracted from the ground by coal mining, either underground mining or open-pit mining (surface mining). ... A road destroyed by subsidence and shear. ...

The Rhondda Fawr rises near Llyn Fawr - and runs down the Rhondda Valley, (Welsh: Cwm Rhondda) to its confluence with the River Taff at Pontypridd. Rhondda Cynon Taff (Welsh: Rhondda Cynon Tâf) is a county borough in Glamorgan, South Wales. ... Welsh redirects here, and this article describes the Welsh language. ... The River Taff is a large river in South Wales. ... Pontypridd is a town in Glamorgan, Wales, in the county borough of Rhondda Cynon Taff. ...

The river runs through Blaenrhondda where it is joined by the Nant y Gwair via a classical example of a hanging valley. The river then passes through a string of mining towns and villages including Treherbert, Treorchy, Pentre, Ton Pentre, Ystrad Rhondda, Llwynypia, Tonypandy, Dinas, Porth and Trehafod before finally joining the River Taff in Pontypridd. Bridal Veil Falls in Yosemite National Park flowing from a hanging valley. ... Treherbert is a village situated at the head of the Rhondda Fawr valley in south-east Wales, UK. As you enter the area from the direction of Treorchy you view the mountain of Pen Pych. ... Treorchy (Welsh: Treorci) is a village, although it used to be and still has characteristics of a town, in the county borough of Rhondda Cynon Taff, traditional county of Glamorgan, South Wales, lying in the Rhondda Fawr Valley. ... Ton Pentre is a village near Treorchy in Rhondda Cynon Taff, south Wales. ... Llwynypia (also spelled Llwyn-y-pia or Llwyn y pia), is a town in Rhondda Cynon Taff, Wales, lying in the Rhondda Fawr Valley. ... Tonypandy is a town in the county borough of Rhondda Cynon Taff, traditional county of Glamorgan, south Wales, lying in the Rhondda Fawr Valley. ... For other uses, see Porth (disambiguation). ... Trehafod is a village between Porth and Pontypridd in Rhondda Cynon Taff, south Wales. ... The River Taff is a large river in South Wales. ...

The Rhondda Fach has its source very close to the Rhondda Fawr on the hills above Blaenrhondda. The fledgling river is first contained in the Lluestwen reservoir before flowing down into Maerdy and then on through Ferndale, Tylorstown, and Ynyshir before joing its sister tributary at Porth. Maerdy is a town in the county borough of Rhondda Cynon Taff, traditional county of Glamorgan, south Wales, lying at the head of the Rhondda Fach Valley. ... Ferndale (Welsh: Glynrhedynog) is a small town located in the Rhondda Fach valley of the South Wales Valleys. ... Tylorstown is a village located in South Wales in the Rhondda Cynon Taff (Rhonnda Fach) It is neighboured by the village of Ferndale. ... Town in the Rhondda Valley in Wales,UK. The carbonated drink Lurvills Delight,a mixture of Stingy Nettles and Dock leaves,infused with Juniper Berry extract was invented by the Lewis Twins Harold and Iolo,who hailed from the village,in 1895. ...

The mining industry had a catastrophic impact on the quality of the river with all the mine waters being pumped straight into the river with no treatment. For very long periods, probably more than a century, the river was continuously black with coal solids and little if anything could live in the river. This was compounded by the very basic sewage disposal arrangements which saw all the sewage discharged into the same river. Not until the 1970s was there real investment made in improving the sewage treatment arrangements. Sewage is the liquid water produced by human society which typically contains washing water, laundry waste, faeces, urine and other liquid or semi-liquid wastes. ... Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants from sewage. ...

Since the early 1970s the river has been steadily improving in quality largely due to the closure of all the coal mines and through the investment in sewerage and sewage treatment.