Groundwater resources of the South East

South East groundwaterresource

South East groundwaterresource

South East groundwaterresource

Two main aquifers in the South East:

• Unconfined Tertiary limestone (upper) aquifer

• Confined Tertiary sand (lower) aquifer

• Separated by Tertiary clay layers (aquitard)

5 Year Trends in Groundwater

Levels

2003 - 2008

5 Year Trends in Groundwater

Levels

2005 - 2010

South East groundwaterresource

Red lines = water table contours (metres above sea level)

Black lines = groundwater flow direction in the unconfined aquifer

Direction of groundwater flow in the confined aquifer is similar to that of the unconfined aquifer

Unconfined Aquifer Salinity

Blue Lake Levels and Annual Extraction Rate

1970 - 2005

How is water used in the South East?

Area of irrigated activity by method, South East Catchment

region, 2003/04

Total area = 79,118 ha

Area of irrigated activity by crop, South East Catchment

region, 2003/04

Total area = 79,118 ha

(Econsearch,2006)Total Area = 79,118 ha

Pasture44.1%

Pasture/Seed7.0%

Potatoes3.1%

Vines19.2%

Cereals2.3%

Grain Legumes0.7%

Lucerne15.5%

Oilseeds2.4%

Other6.4%

Other0.0%

Recreation0.4%

Vegetables1.6%

Flowers/Shrubs0.2%

Fodder1.8%

Fruit and Nuts1.6%

Total Area = 79,118 ha

Centre Pivot/Lateral Move

37.5%

Fixed Sprinklers5.7%

Travelling Irrigator

6.5%

Drip18.8%

Flood29.8%

Other7.4%

Unknown1.0%

Portable Spraylines

0.4%

Microspray/Minisprinkler

0.3%

How is water used in the South East?

Estimated water pumped by crop, South East Catchment

region, 2003/04

Total volume pumped (95% from unconfined aquifer)=

459,007 ML

Gross value of production of irrigated activity, South East Catchment region, 2003/04

Total GVP = $324.6 million

(Econsearch,2006)

Total Pumped = 459,007 ML

Potatoes3.0%

Pasture/Seed5.2%

Vines4.9%

Fruit and Nuts1.2%

Vegetables0.9%

Oilseeds0.9%

Other0.0%

Recreation0.4%

Other4.6%

Cereals1.1%

Flowers/Shrubs0.1%

Fodder1.1%

Grain Legumes

1.0%

Pasture55.7%

Lucerne25.4%

Total GVP = $324.6 million

Vines58.1%

Vegetables4.0%

Potatoes11.8%

Pasture/Seed3.5%

Pasture12.3%

Fruit and Nuts1.4%

Lucerne6.1%

Other2.9%

Oilseeds0.8%

Other0.0%

Cereals0.5%

Flowers/Shrubs0.8%

Fodder0.6% Grain Legumes

0.2%

How has irrigation changed in the South East?

Irrigation Method

Area (ha) % of Total Area (ha) % of Total Area (ha) %

Flood 26,825 37% 23,542 30% -3,284 -12.2%

Drip 8,700 12% 14,907 19% 6,207 71.3%

Travelling Irrigator 8,700 12% 5,113 6% -3,587 -41.2%

Fixed Sprinklers 2,900 4% 4,518 6% 1,618 55.8%

Centre Pivot/Lateral Move 21,025 29% 29,711 38% 8,686 41.3%

Other or unknown 4,350 6% 1,326 2% -3,024 -69.5%

Total 72,501 100% 79,118 100% 6,617 9.1%

2003/04 Change since 1998/991998/99

Water Regulation Philosophy – NRM Act 2004

Principle of Ecologically Sustainable Development

» Recognises and protects the intrinsic values of natural resources

» Sustaining the potential of natural resources to meet the reasonably foreseeable needs of future generations

South East groundwaterresource

PAV. Permissible Annual Volume, defined as “the volume of water that can be sustainably used or assigned from the unconfined aquifer on an annual basis, in a particular management area.”

Existing PAV (Report DWLBC 2006/02) = 814,537 ML

Total taking allocations (unconfined) at 30/06/07 =

533,512 ML

Total volume pumped in the South East NRM region (2006/07) =

310,954 ML (unconfined)

18,366 ML (confined)

Prescribed Wells Areas

Terminology

• Prescription

• WAP

• Aquifer

• Triggers

• Precautionary principle

• Volumetric conversion

• GDE

• NRM

• A legal document setting out the rules for allocation, use and transfer of water from a prescribed water resource

• Prepared by the NRM Board in each region

• Adopted by the Minister for Environment and Conservation

• Administered by Department for Water (DfW)

What is a Water Allocation Plan (WAP)?

Principles for WAPs

• Best available science and information

• Active involvement of community and stakeholders

• Understanding of demands on water resource

• Appreciating needs of different sectors

• Community ownership of policy

• Regard for state and national policy directions

Concept Statement

 

Board and DfW develop options to address issues in the Concept Statement. Papers for Community Comment.

Community consultation on the preparation of the Draft Water Allocation Plan (A1)

Community consultation on the contents of the Draft Water Allocation Plan (A2)

Board develops draft Water Allocation Plans in collaboration with special interest groups, the Lower

Limestone Coast Reference Group and DfW

How is a Water Allocation Plan developed?

DfW review of plan under preparation

B consultation on the Plan as drafted

Revision for minor amendments and Plan approval by Minister

How is a Water Allocation Plan developed?

Development cont.

Board continues to develop draft Water Allocation Plans taking into consideration submissions and

feedback from A2 Consultation

At least every 5 years and considers:

• Trends in Water Resources

• New Science

• New Policy

• New Law

• Changes in societal views and values

Who’s who in water planning and management?

Board Sub-Committees

Department for Water

South Eastern Water Conservation and Drainage

Board

South East Natural Resources Management Board

Border Groundwater Agreement Review

Committee

Minister for Environment & Conservation

Upper South East Dryland Salinity and Flood

Management Board

Who does a Water Allocation Plan relate to?

Licensed Water Users

• Irrigators and forest

industry

• Industrial

• Public Water Supply

• Recreational

Water Affecting Activities

•Well Drilling

•Dams

•Forestry

Environmental Water Needs

Stock and Domestic

Why develop a water allocation plan?

• To protect the natural assets dependent on groundwater resources.

• To ensure the long term viability of industry and stock and domestic use.

• To provide for equity in rights and consumption of the water resource.

• To ensure resource sustainability for the long term future of our region.

How Can You be Involved in Water Planning?

• Public consultation

• Written submissions

• Information sessions

• One on one

• Request presentations

• Check www.senrm.sa.gov.au

• Use nrmSpace

The really important message…..

A WAP sets out policy to manage a resource that science tells us will become increasingly scarce, in a

way that allows for continued regional growth, protection of our water and does not come at the expense of our other natural assets. All for the benefit of our children's

children.

Volumetric allocations

• Area-based (HaIE) allocations to be converted to Volume-based (Megalitre) allocations

• Conversion factor used to alter allocations

• A number of areas in the South East have, in the past, been over-allocated

• As a result, irrigators in some areas will have their allocations reduced

Annual Water Use Return Forms

• All licensed water use MUST be metered. Failure to do so may incur penalties in accordance with the NRM Act 2004.

• Administered by Department for Water

AWUR forms require:

• Provision of water use figures for the preceding financial year (calculated from meter readings)

• Provision of salinity readings if carried out by landholder

Irrigation BenchmarkingDfW’s Irrigation Benchmarking project is looking at 13 trial sites throughout the South East. Investigations include:

• Monthly sampling for soil water and drainage water

• Piezometer readings for aquifer depth, salinity etc.

• Bi-monthly Sonde readings to look at aquifer salinity stratigraphy

• Soil sampling and analysis pre-Irrigation season

• Post-Irrigation season soil sampling and analysis

• A number of centre pivot catch can tests

Irrigation BenchmarkingRequirement to:

• present and discuss results of investigations, including:

water and salt balances for the trial sites

nitrate leaching under irrigation and its impact on the groundwater resources.

• have community input into development of the best practice management guidelines which are to address/minimise impacts to groundwater resources and increase efficiency of irrigation enterprises.

Automatic Weather Stations (AWS)

• Regional AWS network established

• Recorded data useful when determining irrigation scheduling

• AWS located at Tintinara airstrip, as part of an Innovation Grants project

AcknowledgementsThe South East Natural Resources Management Board gratefully acknowledges the following information providers:

• Rural Solutions SA – Irrigated Crop Management Service

• Department for Environment, Water and Natural Resources