There has been a lot of rain in central Queensland over the last month. Water has been flowing over the Fairbairn dam spillway and the Nogoa River has flooded the town of Emerald with over 2,000 residents seeking emergency accommodation. The Nogoa River flows into the MacKenzie River which flows into the Fitzroy River which flows into the Great Barrier Reef.
According to environmental researcher Alison Jones floodwaters flowing down the Fitzroy River to the Great Barrier Reef will kill off masses of coral around the Keppel Islands.
So, according to Jones, floodwaters are bad for the reef.
The Dawson River, also flows into the Fitzroy River, and was to have a massive dam built in its headwaters. But development of the Nathan Dam was blocked through a court action brought by the Queensland Conservation Council (QCC) and World Wide Fund for Nature (WWF).
If the Nathan dam had been built on the Dawson River would there now be less flooding of the Great Barrier Reef, or would there be not enough flooding? Is there such a things as just the right amount of flooding?
Jennifer Marohasy BSc PhD has worked in industry and government. She is currently researching a novel technique for long-range weather forecasting funded by the B. Macfie Family Foundation.
Just filing this link here about flooding:
http://www.farmonline.com.au/news_daily.asp?ag_id=48260
Maybe not
http://www.dartmouth.edu/~floods/2008007.html
Jennifer,
Floods are not necessarily a bad thing for reefs. Sure, some corals won’t survive being bathed in freshwater however prevailing winds and tides often save this from happening for too long. In fact, floodwaters can be beneficial for both reef corals and fish and may be a necessary boom that injects food in the form of chlorophyll for corals to regenerate faster than on less high latitude reefs.
A dam would prevent this natural cycle and upset the cycle of boom and bust that has made Keppel reefs some of the highest cover of the entire GBR.
However, freshwater is not all that flooding from the Fitzroy Basin brings to the reef. There are also very high sediment, nutrient and pesticide loads that can be harmful to the corals. The sainlity of the water is not necessarily the problem with the floods to the reef.
Cheers,
Annie