The largest flood on record on Australia’s Murchison River was expected to peak at the river’s mouth on March 16, 2006, reported the Australian Broadcasting Corporation. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite captured the top image on the afternoon of March 16. On the right side of the image, the upper reaches of the Murchison River are clearly flooded with a wide blue band expanding out from the river’s normal banks. As it enters Kalbarri National Park, the river winds through deep gorges that prevented it from spreading out. Only when it reaches the coast is the river wide again. A bright blue fan of sediment pours from the mouth of the river where mud-laden flood water is draining into the Indian Ocean. The river overflowed after Cyclone Emma inundated the basin with heavy rain on March 1. The excess water took 15 days to drain to the ocean.
The floods near the shore threatened the city of Kalbarri, which sits just south of the river. The floods may also have caused damage to Kalbarri National Park, which is centered around the river and the 80 kilometers of gorges it has cut in the red rock. Even without superimposed borders, the park’s southern boundary is clearly evident in this image. To the south of the river, a stark line separates the green park from the tan and pink land outside the park. The park’s western border is the Indian Ocean. The park’s northern and eastern borders are not visible.
The MODIS Rapid Response System provides daily images of Western Australia.
NASA images courtesy the MODIS Rapid Response Team at NASA GSFC.