Environment Matters Spring/Summer 2022

Nature’s response to flood Major floods, like the events of early 2022, can have significant impacts to the natural environment, especially riparian corridors and waterways. Flooding is a natural part of a river’s cycle and contributes to the overall long- term form and function of waterways. Positive environmental benefits include creating changes to aquatic habitat such as a diversity of shallow riffle vegetation through physical damage to plants, destabilising riverbanks and submerging plants for longer than they can tolerate. Floods can also spread environmental weeds through seed or plant fragments. Water quality can be significantly impacted through high turbidity and increased bacteria and nutrient loads. These impacts combine to degrade aquatic habitat, creating sub-optimal conditions for fish and aquatic wildlife. The most important environmental actions after a flood include identifying and managing new weed infestations and restoring degraded riparian vegetation. It is also important to monitor water quality or any potential risks to the community. Increasing the density of plants along waterways is the best way we can increase the resilience of waterways to flood impacts. More riparian vegetation can help slow the erosive force of floodwater and lessen impacts to riverbanks and nearby infrastructure. This vegetation is especially important, and has the greatest flood-mitigating potential, in the upper and middle reaches of our waterways. zones, deep pools and snags. However floods can also cause widespread damage to native

Photo courtesy of Healthy Land and Water

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