The floods of 2022 loom large when considering the safety and security of the people of Lismore and its surrounds. Heavy rain in the Richmond Catchment in the Northern Rivers District of New South Wales resulted in a record peak flood height at Lismore of 14.4 metres, with the tragic loss of seven lives and extensive damage to property. So a study by the CSIRO that modelled the entire catchment and the effect of potential mitigation measures has been widely welcomed. The mitigation measures considered in the study were; a total of ten detention basins in the upstream areas, dams that temporarily capture water as it moves down the catchment; and management of the outflow of water in lower reaches as it passes through drains and swamps. Selection of sites for the detention dams were based on local recommendations and their effectiveness. The implementation of all 15 measures showed a significant reduction in flood height, in the order of two metres.
So after last weeks survey of a very extensive bush regeneration project I was astonished to hear that the preferred site for a dam on the Wilson River would flood the entire site we were surveying, including the very spot where the picture below was taken. Not only that, it appears that the detention basin would impact on the Booyong Nature Reserve, one of very few remnants of the massive Big Scrub sub-tropical rainforest that has been 99 percent destroyed by logging and farming over the past century. Surely a very elementary review of the options would have eliminated this location from consideration.
Building new dams will always affect current residents and farmers, and raise economic and environmental issues in their path. The need for balance between present and future needs is ever present in the planning of land use in the Northern Rivers. Approval for housing on land categorised as flood plain or of high environmental value is still happening. Shouldn’t alternative means of mitigation including relocation be considered? Let us hope that the eventual flood mitigation plan for the Richmond Catchment will not involve endangering a rare and valuable remnant of its original vegetation.
One of sixteen Rose-crowned Fruit-Doves counted in last weeks survey. The area this bird and bush occupy would be underwater as part of the mitigation to reduce flooding during times of high rainfall under the CSIRO plan.