You can bring your own canoe (licence or BCU membership needed). There are special requirements for passing through the Ashford Tunnel by canoe and there are locks at Brynich and Llangynidr, which must be portaged.
For the more adventurous, the river Usk offers excellent white-water canoeing during the closed fishing season, and at other times when the river is in spate. Canoeing the River Usk is regulated by an access agreement negotiated by the Welsh Canoeing Association (WCA). It is essential to check the details of the agreement before paddling.
Details of canoeing access agreements in Wales may be found in ‘Canoe Access Guide Cymru’ which is available from the WCA.
You can also hire a canoe on the canal at Brecon with Beacon Park Day Boats
Or you can hire also canoes on the nearby River Wye at Glasbury: