Growing a Healthy Future for the Lower Lakes
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Growing a healthy future for the Lower Lakes Lower Lakes Bioremediation and Revegetation Project | December 2009 Department for Environment and Heritage www.environment.sa.gov.au The Lower Lakes Bioremediation and Revegetation Project is about getting the local community and government working together to help rehabilitate this wetland of international importance. A project is underway in the Lower Lakes and Coorong region to tackle some of the urgent environmental problems, such as acidification and soil erosion, due to low river flows and unprecedented low lake water levels. The current situation The Murray-Darling Basin is experiencing the worst drought since records began in 1891. Record low inflows to the River Murray through drought and over-allocation are having a significant social, cultural, economic and environmental impact on the Lower Lakes and Coorong region – a South Australian treasure of international significance. Water levels are dropping, salinity levels are increasing and soils on the drying lakebeds and wetlands are acidifying. This situation is unprecedented. Future predictions indicate that South Australia’s climate will be more variable. As a result, we must find ways to adapt to a future of reduced water availability – and work towards a future of less reliance on the River Murray, particularly for domestic water supply. The South Australian Government is working with local communities and scientists, technical experts and engineers to: • address immediate drought response issues • plan for worst-case scenarios • develop long-term sustainable solutions. The risks Based on water levels at March 2009, over 20,000 hectares of acid sulfate soils were exposed in Lake Alexandrina and Lake Albert resulting in acidic soils forming over much of the dried out lakebeds. This situation is unprecedented. When potential acid sulfate soils are exposed, a series of chemical reactions occur that generate large quantities of sulfuric acid. In extreme cases, this acidification can cause ecological collapse, killing plants and animals and rendering the water unsuitable for any purpose. Salinity levels are also increasing throughout the region, and in some areas the salinity levels are now too high for the water to be used for drinking, livestock or even irrigation. If salinity levels continue to rise, freshwater fish and other aquatic animals and plants will struggle to survive. Photo: Property at Poltalloch, Lake Alexandrina where aerial seeding was carried out in autumn 2009 The project at a glance The Lower Lakes Bioremediation and Revegetation Project is about getting the local community and government working together to address some of the serious environmental issues this internationally recognised wetland is facing, such as acidification and soil erosion. Revegetation techniques, like planting shallow-rooted cover crops, can help address the impacts of soil erosion and assist natural bioremediation to remove acid in sediments and water. The 2-year project has been made possible thanks to $10 million funding from the Australian Government, and support from the South Australian Department for Environment and Heritage. This funding is in addition to the $200 million that the Australian Government will provide to South Australia to address environmental problems facing the region as part of the South Australian Government’s $610 million Murray Futures program. The program includes developing a long-term plan to secure a healthy, sustainable future for the region. The Department for Environment and Heritage is leading the project, in partnership with: • Milang Progress Association • Goolwa to Wellington Local Action Planning Group • Coorong District Local Action Planning Committee • Ngarrindjeri Regional Authority • Ngarrindjeri Ruwe Contracting • Murray Darling Basin Natural Resources Management Board • Rural Solutions SA. Photo: Results of aerial seeding undertaken on a previously exposed lakebed on Lake Alexandrina Why is this project important? The combined impact of low flows and reduced water quality is affecting the range of plants and animals that can live in the Coorong and Lower Lakes region. As water levels continue to drop, exposing more soils in the region, soil erosion is also a significant problem. It can expose new acid sulfate soils and remove nutrients from the soil, which are needed by plants. Planting vegetation over wide areas of exposed soil will help minimise the effects of wind erosion, and could also reduce the risk of acid sulfate soils in the area. The Bioremediation and Revegetation project aims to address some of these problems by: • providing ecosystem stability and resilience • stabilising sand, dust and soil movement • helping manage acid sulfate soils through bioremediation • improving biodiversity. Bioremediation and Revegetation Project Strathalbyn Rodwell Creek BIOREMEDIATION AND Natural Resource Centre Catchment Group Mt Barker REVEGETATION PROJECT Wellington B A r n e g m a s e R r Revegetation Program 2009-2010 i v R e i v r e F r in n Finniss Tolderol is s R iv e Community planting (277 ha) r Finniss Catchment Group Milang Environmental Nursery Centre Contract crop management Milang and sedge planting (15,730 ha) Lakes Aerial seeding, sedge planting Hub and crop management (4,157 ha) Autumn 2009 Cu Aerial seeding - autumn 2010 rre nc Lake Alexandrina (15,000 ha) yC reek Natural regeneration (1,590 ha) Fertiliser treatment and Clayton Bay natural regeneration (658 ha) Alexandrina Community Foreshore Committee Nursery Goolwa Crop seeding (25 ha) Clayton Bay Weed control (887 ha) Hindmarsh Island Point Sturt Poltalloch Landcare Group Raukkan H i n d m a r s h I s l a n d Narrung Lakes Hub (Milang) S i Goolwa Barrage r R R Mrongovius i c h a Nursery Lakes Hub Outreach r d P Mundoo Barrage (Meningie and Raukkan) e n i n s u l a Community nurseries Boundary Creek Barrage Murray Mouth Revegetation and subsurface Ewe Island Barrage barrier trial sites Y Community acid sulfate soils o u n monitoring sites g Tauwitchere Barrage h u Towns s b a n d Barrages P e n i n Major Roads s u l a Major Tributaries T h e C o Adelaide o Lake Albert r o n 0 20 g Kms Meningie Wellington Melaleuca Centre (Orana) Meningie School Southern Ocean Strathalbyn Rodwell Creek BIOREMEDIATION AND Natural Resource Centre Catchment Group Mt Barker REVEGETATION PROJECT Wellington B A r n e Bioremediation and Revegetation Projectg m a s e R r Revegetation Program 2009-2010 i v R e i v Strathalbyn r e Revegetation Program 2009-2010 F r i Rodwell Creek BIOREMEDIATION AND n Finniss Tolderol n Natural Resource Centre Catchment Group Mt Barker is s R REVEGETATION PROJECT iv e Community planting (277 ha) r Finniss Catchment Group Milang Environmental Nursery Centre Wellington B Contract crop management A r Milang n e g m and sedge planting (15,730 ha) a s e R r Revegetation Program 2009-2010 i Lakes v R Aerial seeding, sedge planting e i v Hub r e and crop management (4,157 ha) F r in n Finniss Tolderol Autumn 2009 is s R C iv Aerial seeding - autumn 2010 urr e Community planting (277 ha) en r Finniss Catchment Group Milang Environmental cy Lake Alexandrina (15,000 ha) Cre Nursery Centre ek Contract crop management Milang Natural regeneration and sedge planting (15,730 ha) (1,590 ha) Lakes Aerial seeding, sedge planting Fertiliser treatment and Clayton Bay Hub and crop management (4,157 ha) natural regeneration (658 ha) Alexandrina Community Foreshore Committee Autumn 2009 Nursery CGuoolwa AeCriraol pse sedeidngin g- a (u2t5u hman) 2010 rre nc Clayton Bay Lake Alexandrina (15,000 ha) yC reek Weed control (887 ha) Hindmarsh Island Point Sturt Poltalloch Natural regeneration Landcare Group Raukkan (1,590 ha) Narrung Lakes Hub (Milang) H i n d m a r s h I s l a n d Fertiliser treatment and S i Goolwa Barrage Clayton Bay Alexarn dRrina Community R Mrongovius natural regeneration (658 ha) i c Foreshore Committee h Nursery Lakes Hub Outreach Nursery a r Goolwad Crop seeding (25 ha) P e Mundoo BaCrrlaagyeton Bay (Meningie and Raukkan) n i n s u WeCeodm cmounntriotyl (n8u87rs eharie) s Hindmarshl Iasland Point Sturt Poltalloch Boundary Creek Barrage Landcare Group Raukkan Murray Mouth Revegetation and subsurface Lakes Hub (Milang) H i n d m a r s h I s l a n d Ewe Island Barrage Narrung barrier trial sites S i r Goolwa Barrage R Mrongovius R i c Y Community acid sulfate soils h a o Nursery Lakes Hub Outreach r d u n (Mmenoinigtoieri nagn dsi tReasukkan) P e Mundoog Barrage Tauwitchere Barrage n h i n u s u s Towns l a b Community nurseries a Bonundary Creek Barrage d Barrages Murray Mouth P Revegetation and subsurface eEwe Island Barrage n barrier trial sites i n Major Roads s Y u Community acid sulfate soils o l a u Major Tributaries n monitoring sites g Tauwitchere Barrage h u T Towns s b h a n e d Barrages P e n C i n Major Roads s u o l Adelaide a o Lake Albert Major Tributaries r T o h n 0 20 e g Kms C o Meningie Adelaide o Lake Albert Wellington r o Melaleuca Centre (Orana) n 0 20 g Meningie School Southern Ocean Kms Meningie Wellington Melaleuca Centre (Orana) Meningie School Southern Ocean What does the project involve? Through the project, a combination of on-ground works are being undertaken to Revegetation Program 2009-2010 improve the region’s environment, including: • mapping and research to select the best locations, techniques and plants to use for revegetation works • on-ground revegetation works, including collecting and propagating native seed for local revegetation, planting, crop and weed management • fencing to protect the lakebed vegetation from stock • ecological monitoring and reporting • developing local action plans, best-practice manuals for bioremediation and revegetation and training materials • holding workshops, information forums and training courses for the local community.