The River Barrow forms a major part of Ireland's inland waterways network, providing an inland link between the port of Waterford and the Grand Canal, which in turn connects Dublin to the River Shannon. There are three sections to the navigation:
The tidal River Barrow, which together with the tidal reaches of its tributaries the River Suir and River Nore constitute 88km (55 miles) of tidal river navigation.
The non-tidal river navigation featuring 23 locks, continuing 66km (41 miles) inland from the tidal limit of the Barrow at St Mullin's to Athy.
The Barrow Line of the Grand Canal connects to the river at Athy and continues northwards a further 45km (28 miles) with 9 locks, connecting to the mainline of the Grand Canal at Lowtown.