Wildfires can cause damage to forested catchments in national parks with varying severity. The Warrumbungle National Park, located west of Coonabarabran NSW, experienced a major wildfire in January, followed by a large rainfall event in February 2013. This wildfire created large areas of open canopy forest with bare or severely reduced groundcover, particularly on the steeper slopes. Waterways and water bodies are also likely to be affected by wildfire, since the removal of vegetation that provides shading and riparian habitat will influence water quality, sediment dynamics and aquatic biodiversity. As part of the post-fire soil and water impact assessment, we conducted a preliminary biogeomorphological survey of Dunphy Lake, the only wetland in the park. The lake was largely dry, with a small isolated pool (pH: 7.64; conductivity: 435 µS/cm; turbidity: 358 NTU on 12 March 2014). Diverse aquatic invertebrates (> 25 taxa) were present in the pool, including taxa that are known to be first colonizers in temporary water bodies of inland NSW. We observed the presence of cattle near the lake, which entered the reserve following the fire, when boundary fences were damaged. Core samples for sedimentological and geochronological analyses will be obtained in the near future in order to understand current and past biogeomorphological aspects associated with wildfire, such as changes to runoff, sediment transport and depositional environments in the lake. This research will help guide post-fire recovery and remedial actions in the Warrumbungle National Park and in NSW national parks more generally.