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In dryland settings, most floodplain wetlands form in low gradient, low energy environments that are characterised by strong interactions between flow, sediment and biota. Some floodplain wetlands are only partly channelled or largely unchannelled, and represent major discontinuities in drainage networks, fundamentally influencing downvalley water and sediment transfer. In the > 15 km² Blood River floodplain wetlands, located in subhumid to semiarid eastern South Africa, field investigations, aerial photographs, and optically stimulated luminescence (OSL) ages provide evidence for development of a major discontinuity during the very late Holocene. Between ~ 800 and 100 years ago, the wetlands were characterised by a through-going, meandering channel set within a floodplain up to 2.5 km wide. A sinuous channel remains in the lower part of the wetlands but during the last ~ 100 years major morphological …