Proposed Basin Plan consultation report

Chapter 10: Critical Human Water Needs

Chapter 10 of the proposed Basin Plan sets out matters relating to Critical Human Water Needs (CHWN), including the amount of water needed to meet CHWN; water quality and salinity trigger points; monitoring, assessment and risk management relating to CHWN; and water-sharing arrangements under the Murray-Darling Basin Agreement.

CHWN is the water required in times of drought for core human needs (drinking, food preparation and hygiene) for essential community services (including emergency services, hospitals and schools) and for commercial and industrial purposes that are vital for the ongoing functioning of the community or national security.

The proposed Basin Plan must specify a volume for meeting the CHWN of communities dependent on the River Murray System. It also sets a volume for conveyance water, that is the water required to ensure sufficient flow in the river system to physically deliver water for CHWN. It includes arrangements that ensure conveyance water can be provided in the driest of seasons. The proposed Basin Plan also includes triggers for determining when water quality is unsuitable for CHWN and a process for responding to any such events.

The Basin states are responsible for securing and providing the water for CHWN. This means that while the plan sets the requirements, they are to be met by the Basin states. Cooperation between the states and MDBA is important, and the provisions in the proposed Basin Plan are supported by requirements in the Murray-Darling Basin Agreement, especially schedule H Water Sharing in Tiers 2 and 3.

Chapter 10 provides for CHWN for communities dependent on the River Murray system. Outside the River Murray system, CHWN will be met through the provisions of part 13 in chapter 9.

70.Issue

Submissions queried how communities that did not depend on the River Murray System were considered in the proposed Basin Plan’s CHWN provisions.

RESPONSE

While the Act requires that the Basin Plan determine the CHWN of communities that depend on the River Murray System for water, MDBA is aware that these needs should be appropriately planned for across the whole of the Basin. The Basin states are responsible for meeting the CHWN of communities, both those dependent on the River Murray system and across the rest of the Basin.

Chapter 10 ensures these needs will be met for communities dependent on the River Murray system and in part 13 of chapter 9 of the proposed Basin Plan requires that all water resource plans include measures to meet CHWN in extreme events that threaten the quality or quantity of water for CHWN. The requirements of both chapters 9 and 10 will be considered in the monitoring and evaluation of CHWN outcomes.

The monitoring and evaluation of the Basin Plan will help to ensure that CHWN are prioritised across the whole Basin.

71.Issue

Submissions questioned how water trade would be used to supplement a town’s water entitlement and CHWN.

RESPONSE

MDBA agrees that the water market should be used where appropriate to supplement water entitlements for all uses, including town water supplies where appropriate. Water supply authorities are able to use water trading to help them meet demands for water. However, the use of traded water to meet CHWN will require careful consideration because water licences have different levels of security and water might not be available on the market when most needed to meet CHWN.

72.Issue

Submitters expressed the view that the salinity triggers for CHWN should consider water quality, not just quantity.

RESPONSE

MDBA agrees that the Basin Plan must ensure water for CHWN is of suitable quality and quantity. The proposed Basin Plan includes triggers for enacting an emergency response if water quality or salinity levels are not suitable to meet CHWN.

73.Issue

In submissions that did not support the proposed Basin Plan’s approach to CHWN, issues raised included that Basin water should not be a major source of water for CHWN for Adelaide and other areas outside the Basin, CHWN should not impact environmental water requirements, and that CHWN would impact reliability of other water users.

RESPONSE

The Basin’s water resources are used to support or supplement the water supplies of communities outside the Basin. The impact of this non-Basin use on the water volumes for CHWN overall will depend on the extent of dependence on the River Murray System of those communities. Adelaide is very dependent and is therefore included. Melbourne, on the other hand, has access to a range of alternative water sources and is not included in the CHWN volumes.

The Australian Government and Basin states have agreed that CHWN are the highest priority use for communities who are dependent on the Basin water resources. As such, they will be allocated before other consumptive uses. In the Millennium drought, actions to set aside enough water for critical human needs did have some environmental impacts. The provisions in chapter 10, and the new requirements in the Murray-Darling Basin Agreement will reduce the chance of this occurring and will ensure it is a last-resort measure.

Chapter 10 ensures a small volume of water is set aside to guarantee water for CHWN. All Basin states have recognised this as the first priority use under the SDL and as such will be allocated before water for other uses.

74.Issue

Submitters disagreed with excluding the needs of stock, permanent plantings and key industries from the CHWN component of the plan.

RESPONSE

Section 86A(2) of the Act defines CHWN as: ‘the needs for a minimum amount of water, that can only reasonable be provided from Basin water resources, required to meet core human consumption requirements in urban and rural areas and non-human consumption needs which, if unmet, would cause prohibitively high social, economic or national security costs.

CWHN is the water required in times of extreme drought for core human needs (drinking, food preparation and hygiene), for essential community services (e.g. emergency services, hospitals and schools) and for commercial and industrial activities that are vital to a community’s ongoing functioning.  

Supplying water for stock, permanent plantings and many other industries is not considered vital to the ongoing functioning of a community (that is, to have prohibitively high social, economic or national security costs). Commercial and industrial activities that could be considered as CHWN may include a large employer or a significant contributor to the national economy. The CHWN provisions have been set up as a bulk volume for each State. This will allow the State governments to work with local water supply authorities to determine the best use of the available water in their area. 

75.Issue

It was submitted that the Basin Plan should also include water for all the needs of towns and rural communities.

RESPONSE

Part 2A of the Act requires the Basin Plan to consider water for critical human needs. Chapter 10 fulfils this requirement for communities dependent on the River Murray system and part 13 of chapter 9 for communities not dependent on the River Murray system. The states remain responsible for meeting the general water requirements for towns and rural communities.

The water use of towns that is not a 'critical human water need' will be managed through the water resource plans. Allowances for population growth will be covered in these plans in accordance with state water laws while remaining within the SDL for the water resources of the area. The setting aside of CHWN volumes enable towns to get through extreme events, the volumes stated do not reflect the water required by communities most of the time.

76.Issue

Submissions did not support the volumes proposed for CHWN. More specifically, submissions questioned Adelaide’s reliance on the Murray as a domestic water supply. Some suggested Adelaide should rely on desalination, captured storm water and water recycling to provide its water needs.

RESPONSE

The Act requires the Basin Plan to set volumes for CHWN for communities dependent on the River Murray system (including Adelaide). This is a small proportion of urban and rural water use but ensures basic needs can be met in extreme conditions. Water for urban areas and stock and domestic use will continue to be managed through state water laws. Chapter 10 will help ensure that in the very dry conditions water for critical human needs can be provided without impacting environmental entitlements.

The South Australian government’s water security plan, Water for Good, seeks, among other things, to reduce Adelaide’s reliance on the River Murray system. However, the River Murray continues to play an important role in supplying water during drought, and because of this, Adelaide’s needs are included in South Australia’s CHWN volume.

This volume will be reviewed in the future and could be reduced if water provided from other water sources reduces the volume of water required from the River Murray system to meet Adelaide’s CHWN.

77.Issue

Submissions discussed the apparent discrepancy between salinity and water quality triggers for CHWN in chapter 10 of the proposed Basin Plan and the WQSMP in chapter 8.

RESPONSE

Under the proposed Basin Plan, a salinity trigger of 840 mg/L total dissolved solids or greater, extracted from any site upstream of Wellington, South Australia, defines when water quality in the River Murray system becomes unsuitable for CHWN.

In chapter 10 of the proposed Basin Plan the salinity trigger that defines when water is unsuitable for CHWN is much higher than the salinity objectives set out in chapter 8 of the plan — 840 mg/L total dissolved solids compared to a target value of 500 mg/L.

This is because the objectives outlined in chapter 8 apply to normal river conditions; they represent the water quality desired for most circumstances. The water quality and salinity triggers in chapter 10 are about extreme conditions, usually when there is very little water in the river; they do not represent the level expected in normal conditions.