Statement on localised flooding

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Statement on localised flooding - update

Our communities support the importance of connectivity flows in drought. We fully support flows to provide critical human needs.

Our own regions like many along our rivers, have had critical needs that have had to be met, and we are thankful of this rain which is addressing those local needs with towns and people receiving their stock and domestic flows.

The Department has been managing our systems for some time (the most recent order 30 January 2020) with all river flows being protected for these needs.  The Department decided to extend those restrictions onto floodplain harvesting via text message at 4pm on Friday (7 February 2020).

Following significant local rainfall in some areas, temporary restrictions were lifted progressively for some forms of water access (not all) in isolated areas of the Namoi and Gwydir catchments to assist those individuals in managing on-farm water.  Exemptions also progressively expire, return to temporary restrictions, in the coming days.

Those who live on the floodplain know that managing a flood in real time is challenging.  We know they can be both damaging and a life support.   It’s important we recognise that flood works are designed across these floodplains to protect infrastructure like roads, towns as well as farms.

However, the rainfall that has fallen locally has meant there has been a real risk to infrastructure which could not be reasonably managed.  At the peak of the event, many were blind given the failures in real-time and predictive tools to manage floodplain flows.

We have a small selection of the floodplain that is trying to manage these floods within the new rules, which have been changing over the weekend while other parts of our valley remain dry.  The estimated volume of take during a flood, like these, are often small compared with the total flows.  Measurement and review of the event will provide new data on these aspects.

We are as eagerly watching the progression of the river flow down our system, the first natural flow these sections have seen since 2016 in anticipation of understanding how far this water is going, if it reaches a stream or river and when critical needs for everyone have been met.  With the Gwydir, Namoi, Castlereagh and Marthaguy in the lower Macquarie, Condamine (QLD),  Weir River (QLD) all flowing to some degree.   Estimates and forecasts are available from WaterNSW via https://www.waternsw.com.au/supply/regional-nsw/operations-updates. 

Key Facts:

  • High rainfall in some areas of the region near Bellata, Mallowa, Bullarah and Collarenebri resulted in localised flooding with more than 200mm recorded on some farms.
  • The Department made decisions to progressively lift restrictions for short periods of time, from Saturday 8th February, in only four out of twenty-eight sub-catchments in the Gwydir, where the flooding was occurring.  https://www.industry.nsw.gov.au/water/allocations-availability/temporary-water-restrictions
  • Flows in the Barwon River upstream of the Gwydir, were evident prior to flooding and continue with 45,000ML measured at 12 February 2020 via WaterNSW https://www.waternsw.com.au/__data/assets/pdf_file/0003/153660/Barwon-Darling-flow-12-Februray-2020.pdf
  • Barwon River flows are now predicted to reach Lake Wetherell part of Menindee Lakes system by WaterNSW https://www.waternsw.com.au/__data/assets/pdf_file/0003/153660/Barwon-Darling-flow-12-Februray-2020.pdf
  • The Department provided an event summary fact sheet and rationale on 13th February 2020   https://www.industry.nsw.gov.au/__data/assets/pdf_file/0005/289994/northern-basin-rainfalls-flows-fact-sheet.pdf         
  • Issues with accessibility and quality of information on the real-time data gauging network meant farmers could not monitor stream levels accurately.
  • The localised nature of the flooding meant not all farms in the exempted areas had either unregulated or overland flow access triggered.
  • The small volume of allowed take was naturally restricted due to the fast-flowing nature of the flood at the headwaters of the floodplain, damage to farm infrastructure and the management of on-farm rainfall, which was always allowed.
  • Industry has request voluntary measurement data to help inform a review of the process and the future licencing program.


 

Making Every Drop Count

Securing a future for the Gwydir Valley through Irrigated Agriculture.