River Ogmore

The River Ogmore (Afon Ogwr in Welsh) is a river in South Wales popular with anglers. It runs generally from north to south from the Ogmore Vale and Gilfach Goch, past Bridgend and Ogmore. The River Ogmore rises at Craig Ogwr (527m) in the Ogmore Valley as the Ogwr Fawr before linking with the Ogwr Fach at Blackmill. The River Llynfi, the River Garw and finally the River Ewenny in its estuary are all tributaries of the Ogmore which flows into the sea between Ogmore-by-Sea and the Merthyr Mawr sand-dunes.
The Ogmore has two major branches in its headwaters: the Ogwr Fawr which flows south through Nantymoel, Ogmore Vale and Lewistown; and joining it from the east the Ogwr Fach which flows through Gilfach Goch. After the confluence with the Nant Iechyd, they join to form the Afon Ogwr at Blackmill.
Most of the headwaters flow over carboniferous coal measures overlain by glacial drift and fluvial gravels. The valleys are reasonably broad for a small river, and many of the tributaries meandered through their valleys in the past. The considerable urbanisation, especially in the 19th century, confined most rivers to rather narrow artificial channels, bordered in places such as Bridgend with concrete flood protection walls.
The industrialization of the valley of the Ogmore by mining and heavy industry severely damaged much of the natural environment of the river. However, there has been an improvement in recent years and it supports a healthy population of aquatic invertebrates. The river does still have some problems though, including its proximity to major industrial plants, insensitive development and invasive weeds.