Dungarvan Harbour is a coastal bay and estuary located at the head of Dungarvan Bay in County Waterford, Ireland. The harbour is formed by The Quay fronting the town of Dungarvan on its western side and is situated at the mouth of the Colligan River, which divides the town from Abbeyside to the east. The bay itself is approximately two and a half miles wide, with its western limit defined by a one and a half mile sandbar called The Cunnigar. The harbour is an east-facing, extensive bay, offering a mix of open water and sheltered estuary conditions. The area is a designated Ramsar Wetland Site, indicating significant ecological value.

For paddlers, the primary public launch point is the harbour slip in Dungarvan, directly accessible from the town quay area. The tidal range is significant and critical for trip planning. The harbour's appearance changes drastically between high and low tide, transforming from a deep harbour to expansive mud flats. This substantial tidal exchange affects water depth, particularly in the approach channel. Navigation buoys mark the channel, but charted depths can be as little as 0.2 metres at Lowest Astronomical Tide near the town quay, meaning paddlers must plan their start and return times around high tide to ensure sufficient water for accessing the slip. The bay is exposed to southwesterly gales, which can send a heavy swell into the area, creating potentially hazardous conditions. The fetch across the open bay means wind can quickly build choppy water. The harbour is a working area with a sailing club pontoon and visiting boats, so paddlers should expect other vessel traffic and maintain awareness, particularly in the main channel.

The surrounding area offers scenic views of the town, Dungarvan Castle, and the distant Helvick Head. The Waterford Greenway crosses a bridge over the harbour, providing a notable landmark. Wildlife is present in the intertidal zone, especially when the tide is out. Water quality has been historically impacted but major wastewater infrastructure improvements have been made, with the area now noted for its clean waterways. The Dungarvan Harbour Sailing Club is active in the harbour and manages the pontoon facilities. The overall character is that of a historic, working harbour within a large, scenic bay, where careful attention to tide and weather is essential for a safe and enjoyable paddle.