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West Gippsland estuaries natural openings and closures shape vital ecosystems this autumn

West Gippsland's estuaries naturally open and close, supporting ecosystems. This Autumn, several estuaries are closed, benefiting wildlife. Artificial openings are managed with long-term efforts to support natural processes and reduce interventions.

By news@gippsland - 6th March 2025 - Back to News

Estuaries are dynamic and often in a state of transition. This Autumn is a great example of an environmental zone that is in flux. Across West Gippsland, estuaries are super important, working hard to soften the transition as rivers meet the sea. Many of the region's estuaries open and close to the sea as conditions change and this is a natural and important process.

Victoria's estuaries naturally close at times, supporting ecosystems. Artificial openings may be needed to reduce flooding risks. A fact sheet explains estuary functions during low flows

Natural estuary cycles

This Autumn, Bourne Creek, Merriman Creek, Kugerungmome/Powlett River and Wreck Creek Eastern Branch Estuaries are closed to the sea. These closures are part of a natural process. During times of low river flows and moderate-high tides and swells they can stop flowing to the ocean because a sand bar forms across the entrance.

These estuary closures are good for the river because they provide calm, stable waters for fish to feed and breed, help the native plants and increase areas for birds to feed. Under natural conditions, when an estuary is closed, water levels rise over time and eventually erode the sand bar. - this usually happens with high rainfall in winter and spring. These natural openings are important because they reset the estuary and floodplain by flushing out nutrients and salt.

Managing estuary openings

Estuary closures sometimes impact the environments and infrastructure we rely on like farmland, recreational assets, roads and bridges. So, to keep things safe for us, an artificial opening may be needed.

Artificial openings are when a channel through the sand to reconnect the estuary to the ocean is undertaken manually. This usually happens during times of lower flows and are not as effective as a natural opening at flushing out nutrients and salt from the estuary.

West Gippsland CMA's role is to manage the approvals if an artificial opening is needed. This task is complex, and something not done lightly. We do a thorough risk assessment to minimise possible impacts to the environmental, cultural, social and economic values of the estuary.
H2:Natural estuary flow
In the long-term, we are working with landholders, land managers and Traditional Owners towards a vision of reducing the need for artificial openings at sites along the Bunurong and Mullungdung coast (Kilcunda to Seaspray) and letting natural processes flow at sites like Kugerungmome/Powlett River that are loved and highly valued by the community.

At Kugerungmome/Powlett river estuary, we are working with partners to enable the mouth to open and close naturally which is the ultimate vision. If this vision can be achieved it will have many benefits, not just for the estuary and its floodplain but also for the socio-economic values such as tourism and recreational opportunities.

Pictures from West Gippsland Catchment Management Authority website.

Source: http://gippsland.com/

Published by: news@gippsland.com