Little Brosna River


The Little Brosna River rises near Dunkerrin, County Offaly, Ireland. It flows for 36 miles before joining the River Shannon.

Course

The river rises near Dunkerrin, and enters the River Shannon near Victoria Lock, Clonahenoge. It flows over an area of limestone then passes through an area of Callow before merging with the Shannon. It forms part of the boundary between County Offaly and County Tipperary.

Bridges

Sharavogue Bridge built in the early 1850s carries the R492 road over the river which here forms the boundary between the townlands of Sharavogue and Ballincor Demesne. The bridge is listed as being of architectural and technical interest.
Railway Bridge at Glasderry More is a latticed metal bridge carrying the railway line over the Little Brosna.
Riverstown Bridge with five arches carries the N52 across the Little Brosna. This is a narrow bridge at 5.15m between parapets; traffic negotiating this bridge often has to give way to other vehicles.
Croghan Bridge a stone bridge of three arches from the mid-18th century, it carries the Croghan Road, Birr across the Little Brosna.
Ivy Bridge crosses the river within the demesne of Birr Castle, just downstream of the confluence of the rivers Camcor and Little Brosna.
Derrinsallow Bridge, built about 1850, has three arches of dressed limestone and rubble. It crosses from County Tipperary to County Offlay.
New Bridge built about 1820 is the last crossing before joining the Shannon. It has five rounded arches of limestone. The bridge takes the R438 road between County Tipperary and County Offaly.

Angling

The Little Brosna is a popular angling river, particularly known for its brown trout. An electric fishing survey of the river at Riverstown was conducted in September 2012 by Inland Fisheries Ireland. Species noted here were brown trout, lamprey, salmon and stone loach.

Drainage

The Little Brosna Water Management Unit Action Plan covers 681km2 in County Offaly, North Tipperary and County Laois.
Sharavogue Bog is a raised bog situated on the flood plain of the Little Brosna at Sharavogue in County Offaly. It is an example of a type of habitat that is becoming increasingly rare in Ireland and Europe and is on the list of Special Areas of Conservation, as listed by the National Parks and Wildlife Service.
Redwood raised bog has developed on the southern margin of the Little Brosna flood plain at its confluence with the Shannon. It forms part of the Little Brosna Callows Area of Scientific Interest, which is of international importance as a wildfowl habitat and as a classical example of a flood plain ecosystem. The reserve includes the last relatively intact bog dome on the flood plain margin as well as a dried out portion of another dome and an area of fen. The intact dome has a typical raised bog flora and in the centre it retains quaking areas and numerous bog pools. Established in 1991 it is in state ownership.