The Waiuku River flows through the historic town of Waiuku and empties into the Manukau Harbour, forming a tidal estuary that serves as the starting point for at least two organised kayak routes in the Auckland/Franklin region. The estuary is tide-dependent, so paddlers need to plan trips around tidal cycles, though the waters are described as mainly sheltered with easy access to numerous safe landings throughout.

The launch point for both routes is Tamakai Reserve in Waiuku. From there, the WEKA (Waiuku Estuary Kayak Adventure) route follows the tidal estuary upstream approximately 2.5km to Waitangi Falls, making it a short out-and-back suitable as a day trip. The return leg can be varied by paddling via the Waiuku Sandspit beach. The Wai-manu Trail is a longer route of 43km that continues beyond the estuary toward the Manukau Harbour and can be completed one way over two to three days at a casual pace. Most landing points along the Wai-manu Trail have council-maintained toilet facilities.

The estuary setting has historical and cultural associations with the town of Waiuku, which is noted as a historic settlement. The Waitangi Falls, at the upstream end of the WEKA route, is a local recreational spot.