Connectivity Wet low and point bars Pulsed baseflow (~500 ML/day) from Chaffey Dam days in July 2012 over past three years. High Connectivity Water quality Fish spawning, recruitment, movement and condition Fresh flow (1 000–4 000 ML/day) to provide connectivity and wet medium-level benches, point bars and riparian zone 2–3 years Average return interval Flows greater than 1 000 ML/day over 3 days in July 2012 Not met Not met HIGH Demand has not been fully met in recent years. Maintain / Improve Insufficient water under a very low water availability scenario to contribute to this demand. High Low Critical See references at Table 2a Carryover potential Low to moderate proportion of allocations carried into 2016–17. NOTE: No carryover provisions in the Peel Valley. Low to moderate proportion of allocations may be carried over to 2017–18, but will depend upon resource availability and demands. Level of carryover will depend on environmental demands and resource availability. Trade potential Moderate to high need to augment available allocations given recent dry conditions. Therefore should market conditions improve there is likely to be a desire to purchase allocation or supplementary flow access to assist in meeting high demands. Sale of allocations unlikely considering moderate and high demands. Moderate to high need to augment available allocations given recent dry conditions. Therefore should market conditions improve there is likely to be a desire to purchase allocation or supplementary flow access to assist in meeting high demands. Sale of allocations unlikely considering moderate and high demands. Potential to will depend on environmental demands and resource availability. Table 2c: Environmental demands, potential watering in 2015–16 and outlook for coming years in the Namoi River Valley –HIGH WATER RESOURCE AVAILABILITY IN 2015–16 Environmental assets Physical and process assets Indicative demand (for all sources of water in the system) Required frequency (maximum dry interval) Watering history (from all sources of water) 4 2015–16 Implications for future demands Met in 2016–17 2012–13 2013–14 2014–15 benches
Connectivity Wet low and point bars Pulsed baseflow (~500 ML/day) from Chaffey Dam days in July 2012 over past three years. Connectivity quality Fish spawning, recruitment, movement and condition Fresh flow (1 000–4 000 ML/day) to provide connectivity and wet medium-level benches, point bars and riparian zone 2–3 Average return interval Flows greater than 1 000 ML/day over 3 days in July 2012 Not met Not met HIGH Demand has not been fully met in recent years. Improve Environmental could contribute to providing a fresh flow if allocations become available and there are other adequate flows in the system. Moderate to high Low High See references at Table 2a Carryover potential Due to small holdings, low to moderate proportion of allocations carried into 2016–17. NOTE: No carryover provisions in the Peel Valley. Low to moderate proportion of allocations may be carried over to 2017–18, but will depend upon resource availability and demands. Level of carryover will depend on environmental demands and resource availability. Trade potential Moderate to high need to augment supply, recent dry conditions. Therefore should market conditions improve there is likely to be the desire to purchase allocation or supplementary flow access to assist in meeting high demands. Sale of allocations unlikely considering moderate and high demands. Moderate need to augment available allocations. Sale of allocations may be considered, although there is expected to still be some moderate to high demands requiring water. Potential to trade will depend on environmental demands and resource availability.
Wetlands / Anabranches Commence to fill wetlands preferably in late spring/summer and late winter over 45 days (min. 7 consecutive days): 4 000–4 500 ML/day at Bugilbone Greater than4 600 ML/day at Boggabri (for Barbers Lagoon) Greater than 3 300 ML/day at Duncan’s gauge 5. Connectivity with anabranches: contribute flows to supplement natural unregulated freshes to connect the river with low commence to flow anabranches, provide off channel habitat, support riparian vegetation, and support fish movement, spawning, recruitment and condition. Peel River channel Baseflows: Minimum variable low baseflow (greater than 3 ML/day) from Chaffey Dam Pulsed baseflow (~500 ML/day) from Chaffey Dam 6. Variable baseflows: Contribute to a variable baseflow, likely during or after a period of low flows, to provide refuge habitat, maintain resilience, provide hydrological connectivity, and maintain water quality, as well as fish movement and population resilience. Fresh flow (1 000–4 000 ML/day) 7. In-channel freshes: Contribute to freshes in conjunction with other flows to provide habitat, support ecological processes, maintain riparian vegetation, and support fish movement, spawning, recruitment and condition Note: Under certain resource availabilities, options may not be pursued for a variety of reasons including that environmental demand may be met by unregulated flows and that constraints and/or risks may limit the ability the deliver environmental water.
From planning to decision making It is important to distinguish between planning and operational decision making. As shown in Figure 7, planning allows the Office to manage the environmental water portfolio in a holistic manner and is an exercise in developing a broad approach or intention, based on the key drivers (demand and supply). Decision making throughout each year builds on the intention by considering in more detail the specific prevailing factors and additional factors such as costs, risks, constraints to water delivery and market conditions. Figure 4: Planning and decision-making for Commonwealth environmental water use Further information For further information on how the Office plans for water use, carryover and trade, please visit our web site use: Carryover: Trade: Discussion Paper – Trade of Commonwealth Environmental Water and Commonwealth Environmental Water Trading Framework: Attachment A – Expected outcomes from the Basin-wide environmental watering strategy Expected outcomes from the Environmental Watering Strategy (MDBA 2014) that are relevant to the Namoi are described below. FLOWS AND CONNECTIVITY Baseflows are at least 60 per cent of the natural level. Contributing to a 10 per cent overall increase in in the Barwon-Darling. A 10–20 per cent increase in the frequency of freshes and bankfull. VEGETATION Maintain the current extent of forest and woodland vegetation and non woody vegetation. No decline in the condition of black box, river red gum and coolibah. Improved recruitment of trees within black box and river red gum communities Vegetation extent Area of river red gum (ha) Area of box (ha) Area of coolibah (ha) Shrublands Non–woody water dependent vegetation 6 100 800 4 200 Closely fringing or occurring within the River