Page 252 - VEWH Seasonal Watering Plan 2020-21
P. 252

 5.4 Goulburn system
Social, recreational and economic values and uses
In planning the potential watering actions in Table 5.4.1, Goulburn Broken CMA considered how environmental flows could support values and uses such as:
• water-based recreation (such as boating and fishing)
• riverside recreation and amenity (such as walking, camping and other outdoor activities)
• socio-economic benefits (such as irrigation diverters and water supply for settlements on the Goulburn River).
The Goulburn River provides numerous recreational and economic benefits. Using water for the environment to provide fish passage and habitat and delivering freshes
to encourage fish migration and spawning enhances
native fish populations for recreational benefit. Following community feedback, the timing of a targeted environmental flow in November/December is planned to reduce impacts on river access, benefiting anglers and local businesses. This flow will be identified in Table 5.4.1 with an icon.
The delivery of the spring/summer fresh provides a cue
for golden perch to spawn, and it is timed to minimise impacts on regional communities and businesses during the annual Murray cod opening weekend — the first weekend in December — while still ensuring the environmental objectives of the fresh can be achieved.
Recent conditions
Conditions in the Goulburn catchment in 2019–20 were very similar to those in 2018–19, with below-average rainfall in winter/spring. Temperatures throughout most of the year were above the long-term average, particularly in summer, leading to high evaporation rates from storages. Heavy rainfall in autumn helped replenish storages and resulted
in a series of natural flows being passed at Goulburn
Weir. Despite below-average inflows to Goulburn system storages in 2019–20, sufficient water was available for the environment through carryover and new allocation to meet high-priority flow requirements throughout the year.
Little natural flow occurred below Goulburn Weir in winter, and water for the environment was used to deliver a winter fresh in July 2019. This was followed by variable low flow that aimed to pass mid-Goulburn tributary inflows to the lower Goulburn River below Goulburn Weir. Conditions remained dry in spring, with a spring fresh delivered from September to October 2019 to support native fish and to trigger the germination of bank vegetation. IVTs started after the spring fresh, and no environmental water was delivered between mid-November 2019 and mid-March 2020. IVTs were delivered as a series of pulses (to reduce the effect
on bank vegetation), but flows were consistently above
the recommended environmental limit in summer/autumn. Although high IVT flows likely compromised some of the lower bank vegetation outcomes that were achieved by the spring fresh, wetting of the middle-to-upper bank during the spring fresh facilitated the growth and seed development
of existing vegetation, provided carbon and nutrient
cycling benefits and maintained habitat for waterbug communities. Higher rainfall in autumn delivered several natural flow events in the lower Goulburn River. Water for the environment was used to slow operational recessions after spills at Goulburn Weir, to minimise the risk of erosion and bank slumping.
Water for the environment delivered in the Goulburn River
is reused at downstream sites along the Murray River, after a deduction for losses. In 2019–20, environmental flows that passed through the Goulburn River were subsequently used to support native fish objectives in Gunbower Creek, wet wetlands in the Gunbower and Guttrum forests and the Hattah Lakes system, and support ecological objectives
in SA. Water for the environment that is delivered from
the Goulburn system makes a significant contribution to environmental objectives further downstream, which helps to achieve environmental outcomes at the Murray-Darling Basin scale.
Scope of environmental watering
Table 5.4.1 describes the potential environmental watering actions in 2020–21, their functional watering objectives (that is, the intended physical or biological effect of the watering action) and the longer-term environmental objective(s) they support. Each environmental objective relies on one or more potential environmental watering actions and their associated physical or biological functions.
  Watering planned to support angling activities
   250 | Victorian Environmental Water Holder | Seasonal Watering Plan 2020–21

   250   251   252   253   254