The River Brosna () is a river within the

Shannon River Basin The Shannon River Basin consists of the area containing Ireland's longest river, the River Shannon, and all of its tributaries and lakes. The official Ordnance Survey Ireland length of the Shannon from its Shannon Pot source is made up of tidal ...

Ireland Ireland (, ; ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, in Northwestern Europe. Geopolitically, the island is divided between the Republic of Ireland (officially Names of the Irish state, named Irelan ...

, flowing through

County Westmeath County Westmeath (; or simply ) is a Counties of Ireland, county in Republic of Ireland, Ireland. It is in the Provinces of Ireland, province of Leinster and is part of the Eastern and Midland Region. It formed part of the historic Kingdom of ...

and

County Offaly County Offaly (; ) is a Counties of Ireland, county in Republic of Ireland, Ireland. It is part of the Eastern and Midland Region and the Provinces of Ireland, province of Leinster. It is named after the Ancient Ireland, ancient Kingdom of Uí ...

. The river rises in

Lough Owel Lough Owel () is a mesotrophic lough in the Midlands of Ireland, situated north of Mullingar, the county town of Westmeath. It has a maximum depth of . Water from Lough Owel feeds the Royal Canal, a canal crossing Ireland from Dublin to the ...

north of

Mullingar Mullingar ( ; ) is the county town of County Westmeath in Ireland. It is the third most populous town in the Midland Region, Ireland, Midland Region, with a population of 22,667 in the 2022 census of Ireland, 2022 census. The Counties of M ...

and is a tributary of the

River Shannon The River Shannon ( or archaic ') is the major river on the island of Ireland, and at in length, is the longest river in the British Isles. It drains the Shannon River Basin, which has an area of , – approximately one fifth of the area of I ...

. It meets the Shannon at

Shannon Harbour Shannon Harbour () is a small village situated on the banks of the Grand Canal (Ireland), Grand Canal in County Offaly, Ireland. The older or regional name of the village is ''Cluain Uaine Bheag'', meaning "Clononey Beg" or "little Clononey," na ...

. The River Brosna is 49.25 miles (79 km) in length.

Course

The Brosna begins as a small river, flowing from

in a south-south-westerly direction through

, into Lough Ennell. From Lough Ennell, the river Brosna flows into Kilbeggan, where it still powers the mill at Kilbeggan Distillery. The Brosna continues flowing southwest through Clara, Ballycumber and Pullough. East of Ferbane it is joined by the Silver River. From Ferbane it heads to

, north of

Banagher Banagher ( or ) is a town in Republic of Ireland, Ireland, located in the midlands, on the western edge of County Offaly in the province of Leinster, on the banks of the River Shannon. The town had a population of 3,000 at the height of its ...

, where it joins the Shannon

Fishing

The river Brosna is popular for fly fishing and has stocks of

brown trout The brown trout (''Salmo trutta'') is a species of salmonid ray-finned fish and the most widely distributed species of the genus ''Salmo'', endemic to most of Europe, West Asia and parts of North Africa, and has been widely introduced globally ...

as well as some

salmon Salmon (; : salmon) are any of several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the genera ''Salmo'' and ''Oncorhynchus'' of the family (biology), family Salmonidae, native ...

and

grilse Salmon (; : salmon) are any of several commercially important species of euryhaline ray-finned fish from the genera ''Salmo'' and ''Oncorhynchus'' of the family Salmonidae, native to tributaries of the North Atlantic (''Salmo'') and North Pa ...

. However it has, in recent years, suffered somewhat from pollution problems due to its poor assimilative capacity and the discharge of untreated sewage in the Mullingar area during storm conditions. There have also been discharges of pollutants, whether accidental or otherwise, such as one filmed at the bridge of Clonmore industrial estate in Mullingar.

Drainage

Works, to the cost of IR £750,000, were undertaken on the river in the late 1940s and early 1950s to improve drainage in the river’s catchment area. As part of the Arterial Drainage Scheme, designed to tackle poor drainage caused by Ireland’s relatively low-lying topography, the river was deepened and widened, leaving the river with the high banks distinctive of many of the rivers in the Irish midlands that received this treatment. More recently, in late 2008 the river was diverted from the N52 road beside Mullingar in order to accommodate a new roundabout and bridge.An investigation of the effects of an arterial drainage scheme on the rainfall-runoff transformation behaviour of the Brosna catchment in Ireland, Bhattarai, K. P., O'Connor, K. M., EGS - AGU - EUG Joint Assembly, Abstracts from the meeting held in Nice, France, 6–11 April 2003, abstract #12112.

References

{{DEFAULTSORT:Brosna, River Rivers of County Offaly Rivers of County Westmeath Tributaries of the River Shannon