FOLLOWING THE DODDER RIVER FROM MILLTOWN TO CLONSKEAGH
The Dodder lay well beyond the original city of Dublin but began to have an important impact in the 13th century, when water from its course was diverted to boost the small Poddle River, which in turn did supply fresh water to parts of Dublin.
Over centuries, the Dodder and its tributaries drove many mills, crucial to Dublin's industrial base, but all are now disused. In many cases, all traces have been erased but there are some indications, such as of millraces.
The de Meones family, who gave their name to the nearby suburb of Rathmines, owned a mill in that area as early as the mid-fourteenth century.In the sixteenth century much of the surrounding lands belonged to the Talbot family, ancestors of the Talbots of Mount Talbot. In the seventeenth and eighteenth centuries the Domvile family, who owned much of Templeogue, effectively controlled access to much of the river, which passed through their estates. At that time the Dodder was the main source of Dublin's drinking water, and whether fairly or unfairly, the Domviles were accused of using their control of the Dublin water supply to further their own selfish ends, by threatening to divert its course if their wishes were not met. In fact the legal right to control the course of the river was vested in the Mayor and Corporation of Dublin; this was confirmed by a legal ruling as early as 1527.
The Dodder rises on the northern slopes of Kippure in the Wicklow Mountains and is formed from several streams. The headwaters flow from Kippure Ridge, and include, and are often mapped solely as, Tromanallison (Allison's Brook), which is then joined by Mareen's Brook, including the Cataract of the Brown Rowan, and then the combined flow meeting the Cot and Slade Brooks.
In the river's valley at Glenasmole are the two Bohernabreena Reservoirs, a major part of the Dublin water supply system.
The Dodder is 26 kilometres (16 mi) long. It passes the Dublin suburbs of Tallaght and then Firhouse, travels by Templeogue, passes Rathfarnham, Rathgar, Milltown, Clonskeagh, and Donnybrook, and goes through Ballsbridge and past Sandymount, before entering the Liffey near Ringsend, along with the Grand Canal, at Grand Canal Dock.
There is a weir just above the bridge at Ballsbridge and the river becomes tidal roughly where the bridge at Lansdowne Road crosses it. The Dodder and the River Tolka are Dublin's second-largest rivers, after the Liffey.