Impacts of flooding on the South and East Alligator Rivers and the coastal margin between 30th and 31st of January 1998, March 1998

1998

Internal Report 277
Saynor MJ & Hall R
Supervising Scientist Division
Department of the Environment

About the report

The top half of the Northern Territory received substantial rain during the last two weeks of January as a result of a rain depression travelling from east to west across the Top End. The rain depression (ex Tropical Cyclone Les) had circled around most of the Top End before becoming stationary and dumping large amounts of rain in the upper catchments of the Katherine and South Alligator River. This rain resulted in extensive 'record' flooding in the township of Katherine on the 1998 Australia Day weekend and substantial flooding down the South Alligator River over the course of the next week. In Kakadu National Park (KNP) flooding of the Arnhem and Kakadu Highways resulted in their closure for various periods of time.

The flight was instigated by a request from Mike Saynor (Mouse) (Wetlands) to record (photograph and video) the wetlands and coastal margins (salt water intrusions etc) of KNP during the Wet season, in particular during a period of flooding. Dr Arthur Johnston agreed with the request and suggested that it was a good idea to record the impacts of the flooding for the entire length of the South Alligator River catchment, starting from the head waters and flying down the length of the river to where it enters van Diemen Gulf.