Environmental water delivery references
Environmental water delivery: Namoi River collates the operational and administrative arrangements for the delivery of environmental water to the Namoi River. The document provides an overview of the environmental assets and potential environmental water use options. This work has been undertaken to support the efficient and effective use of environmental water and to engage communities on how this may best be achieved. This aims to encourage community discussion and feedback on the use of environmental water, to identify future opportunities and recognise operational risks and constraints. Comments on the document are encouraged and can be provided to: ewater@environment.gov.au.
Environmental watering in the catchment in previous years
2021–22
| Watering action | Amount of water delivered (ML) |
|---|---|
| Lower Namoi River | 0 |
| Peel River | 0 |
Environmental watering in the Namoi River in 2021-22
Status: Action not implemented
About the watering
Up to 10,000 ML of Commonwealth water for the environment was approved for use in the lower Namoi River in 2021–22. If required, this water was expected to support further post-drought recovery, increased connectivity, and to improve the condition of native fish populations.
Rainfall improved storage levels in Keepit Dam and increased tributary flows into the lower Namoi River, particularly during late spring and summer. This resulted in many environmental demands being met. Therefore, no Commonwealth water for the environment was delivered this year.
Environmental watering in the Peel River
Status: Action not implemented
About the watering
Up to 1,257 ML of Commonwealth water for the environment was approved for use in the Peel River in 2021–22. If required, this water was expected to be delivered in conjunction with the NSW environmental contingency allowance.
This water was expected to help support further recovery in the Peel River following extreme drought, helping to protect and build resilience for native fish and other animals such as platypus.
Rainfall resulted in Chaffey Dam spilling for much of the 2021–22 year, with good river flows meeting many environmental demands in the river downstream. Therefore, no Commonwealth water for the environment was delivered this year.
2020–21
| Watering action | Amount of water delivered (ML) |
|---|---|
| Lower Namoi River | 0 |
| Peel River | 395 |
Environmental watering in the Namoi River in 2020-21
Status: Action not implemented
About the watering
Up to 2,500 ML of Commonwealth water for the environment was approved for use in the lower Namoi River between December 2020 and June 2021. If required, this water was expected to provide very low flows that would support refuge pools, improve water quality, and support native fish.
Rainfall improved storage levels in Keepit Dam and increased flows into the Namoi River from tributaries. This resulted in pulses in December–January, March–April and again in June, which helped to refresh and reconnect refuges. Consequently, no Commonwealth water for the environment was delivered.
Environmental watering in the Peel River in 2020-21
Status: Completed
About the watering
395 ML of Commonwealth water for the environment was delivered in the Peel River in May and June 2021, in conjunction with 1,170 ML of the NSW environmental contingency allowance.
The delivery was designed to:
- Support the recovery and condition of native fish and platypus
- Increase the quality and quantity of available food and habitat
- Increase connectivity and movement opportunities for native fish
- Improve water quality and remove algal build-up.
Further information on the watering action can be found at: 2020–21 Peel River Update.
2019–20
No water for the environment was delivered in 2019–20 in either the Namoi or Peel river during the extreme drought conditions.
2018-19
| Watering action | Amount of water delivered (ML) |
|---|---|
| Lower Namoi River | 5,500 |
| Peel River | 0 |
Namoi River at Tarriaro. Photo: CEWO
Environmental watering in the Lower Namoi River in 2018-19
Status: Completed
About the watering
5,500 ML of Commonwealth environmental water was delivered in the Lower Namoi River downstream of Gunidgera Weir between November and December 2018 to:
- Refresh refuge pools, and maintain and provide access to refuge habitat
- Increase connectivity and improve water quality in pools
- Provide opportunities for the movement of native fish
- Increase the survival and condition of native fish.
Further detail on the watering action can be found at: 2018-19 Namoi catchment updates.
Environmental watering in the Peel River in 2018-19
Status: Action not implemented
About the watering
The purpose of the water delivery was to provide minimum flows in autumn to replenish refuge pools if conditions were extremely dry; or to augment a naturally triggered small fresh to improve connectivity and opportunities for the movement of native fish.
This action was not implemented, as the conditions and triggers required to use Commonwealth environmental water were not met in 2018-19.
2017-18
| Watering action | Amount of water delivered (ML) |
|---|---|
| Lower Namoi River | 4,100 ML |
| Peel River | 1,257 ML |
Environmental watering in the Lower Namoi River in 2017-18
Status: Completed
About the watering
4,100 ML of Commonwealth environmental water was delivered in the Lower Namoi River between March and May 2018 to provide:
- flows to support the conservation stocking of silver perch fingerlings between Gunnedah and Narrabri, by maximising opportunities for fish survival and improved condition
- connectivity for fish movement, condition and dispersal
- baseflows to maintain connection between pools, and improve vegetation condition and water quality.
Environmental watering in the Peel River in 2017-18
Status: Completed
About the watering
1,257 ML of Commonwealth environmental water was delivered in the Peel River in June 2018, in conjunction with 2,635 ML of the NSW environmental contingency allowance. The delivery was designed to:
- increase connectivity and opportunities for the movement and dispersal of native fish, in particular silver perch
- improve instream productivity by wetting low-level benches
- build native fish condition and provide access to increased food resources and habitat.
2016-17
| Watering action | Amount of water delivered (ML) |
|---|---|
| Lower Namoi River | 7,852 ML |
| Peel River | 1,257 ML |
Environmental watering in the Lower Namoi River in 2016-17
Junction of the Namoi and Barwon rivers showing contribution of Commonwealth environmental water in the Namoi River. Photo: CEWO
Status: Completed
About the watering
7,852 ML of Commonwealth environmental water was delivered in the Lower Namoi River from March to May 2017 to provide:
- a recession to irrigation deliveries to provide movement cues for fish
- flows to support the conservation stocking of silver perch fingerlings between Gunnedah and Narrabri
- connectivity along the length of the Lower Namoi River for fish movement, improved vegetation health and refresh pools.
- flows into the Barwon River which supported the native fish that bred in the spring of 2016. This may have also supported fish movement between the Barwon and Namoi rivers.
Environmental watering in the Peel River in 2016-17
Peel River. Photo: CEWO
Status: Completed
About the watering
1,257 ML of Commonwealth environmental water was delivered in the Peel River in conjunction with the NSW Peel River environmental contingency allowance. The ecological objective of this flow was to:
- Return (mimic) the autumn/winter flows in this section that occurred prior to Chaffey Dam being built (restore flow variability)
- Increase the food supply for native fish by “flushing” nutrients off the low in-channel sediment bars
- Redress (in part) the inflow captured in Chaffey Dam last year as it reached its new full supply level
- Provide the opportunity for silver perch (and other native fish) to move upstream into the higher reaches of the Peel River and maintain flows to support juvenile native fish.
2013-16
| Watering action | Amount of water delivered (ML) |
|---|---|
| Lower Namoi River | 0 |
Environmental watering in the Namoi in 2013-16
From 2013 to 2016 Commonwealth environmental water was held in Keepit Dam and carried over to address a potentially much greater environmental demand the following year. A total of 6,227 ML was carried over to 2016-17.
2012-13
| Watering action | Amount of water delivered (ML) |
|---|---|
| Lower Namoi River | 7,727 |
Commonwealth environmental watering in the Lower Namoi River 2012-13
Status: Completed
About the watering
This watering action was the first time that Commonwealth environmental water was made available for use in the Namoi catchment. Commonwealth environmental water was used to enhance in-stream flows along the Namoi River to contribute to the health of in-stream habitat and support native fish by providing improved opportunities for them to feed, breed and shelter.
The use of Commonwealth environmental water in the Namoi catchment was managed by NSW State Water working together with scientists and staff from the NSW DPI (Fisheries), NSW Office of Water, Namoi CMA and Commonwealth Environmental Water Office.
No Commonwealth environmental watering occurred in the Namoi catchment prior to 2012-13.