The Maroochy River meets the sea at Cotton Tree, and the estuary is one of the calmer waterways on the Sunshine Coast. The river is broad and tidal here, fringed with mangroves on the inland side and open water where it approaches the mouth. It is popular for kayaking, stand-up paddleboarding, and fishing — flathead, whiting, and bream are common catches near the mouth.
Kayaks and paddleboards can be hired locally and from operators in Maroochydore. The paddling is straightforward — no significant current to contend with in calm conditions — and the mangrove sections reward closer exploration. Dolphins regularly come into the estuary, especially in the early morning. The Cotton Tree Caravan Park sits right on the riverfront and gives this stretch of water an old-fashioned Australian holiday feel that has survived the development that transformed much of the Sunshine Coast.