Draft Blue Lagoon Management Plan 2023

Blue Lagoon is a place of great significance and importance to our local community.

Its ongoing protection and preservation is a priority for Council and will ensure future generations get to experience its rich biodiversity and value of community connection to this special place.

Why we need a Plan 

Blue Lagoon is a crucial freshwater ecosystem that supports local biodiversity and provides essential benefits to the surrounding community. Once a natural ocean flush with a salt marsh environment, it has evolved into a permanent dune and freshwater habitat due to the presence of Pine trees and Marram grasses.  

The 5 year Blue Lagoon Management Plan (BLMP) has been developed with the aim of conserving biodiversity, cultural heritage and social values – while addressing environmental challenges. It also seeks to promote the area in recognition of its recreational and well-being values as well as establishing an educational centre for local schools and communities.  It sets out a range of priorities and corresponding measures for:  

  • Protection from invasive weeds 
  • Maintaining continuous water in the lagoon 
  • Controlling outflow from weather variations, and 
  • Minimising impacts on private assets and natural biodiversity (e.g during times of heavy rainfall). 

The BLMP acknowledges the challenges of climate change and increased human pressure, and sets out to deliver a proactive and balanced management plan that benefits both the environment and the community. 

What is the focus for the next 5 years? 

The BLMP activities sought to be funded (subject to annual Council budget and funding resource review and allocation) include: 

  • Protecting the lagoon from invasive weeds 
  • Promote area as a mental health hub, and establishing it as an educational Centre  
  • Integrate education on the Red Handfish habitat and advocate for species protection at local, state, and federal levels 
  • Planning for the staged removal of Pine trees and Cumbungi  
  • Regular monitoring of septic systems to prevent lagoon contamination 
  • Continuous water quality monitoring at adjacent Red Ochre (Blue Lagoon) beach for public safety 
  • Community engagement in conservation and restoration activities for improved health and wellbeing 

What we’ve heard so far

The draft BLMP has been informed by extensive consultation and studies, and incorporates input from the community and local stakeholders to ensure a holistic approach to preserving and enhancing Blue Lagoon’s ecological and social value. Stakeholders engaged to develop this draft BLMP included meeting with the following community and professional/academic organisations:  
  • Sally and Chris Johns (authors of the Draft Action Plan for the Blue Lagoon Reserve from which this BLMP is based) 
  • Marine Solutions 
  • University of Tasmania  
  • Southern Beaches Landcare Coastcare Inc.   

 Key outcomes from this initial engagement included: 

  • The consensus within the community on the importance of the Red Handfish, a critically endangered species. The BLMP will integrate education and protection of the Red Handfish habitat into its strategy, ensuring all future activities are consistent with their conservation 
  • Acknowledgement of the ongoing efforts of local community groups in weed management and support for a staged approach over the next 5 years to remove Pine trees and Cumbungi to protect the habitat of various flora and fauna  
  • Addressing the potential contamination of the lagoon by proposing regular monitoring of septic systems within its catchment area, ensuring the protection of biodiversity 

Next steps  

Community consultation has now closed.

Our thanks to everyone who provided feedback and to those able to attend one of the community forums on 21 June 2023.

What we’ve heard so far

Sorell Council has listened to concerns raised and now taken steps to engage additional consultants to provide further independent review and assessment of the stormwater management solution identified in the Draft Blue Lagoon Management Plan (BLMP), as well as consideration of other alternative options that may take into account factors such as outfall, hydrology of the catchment and further environmental assessment and costings.

Will this change what is in the Draft Blue Lagoon Management Plan?  

It is not known at this stage if the work and subsequent report findings on stormwater management from new consultants will significantly change what is proposed in the current version of the Draft Blue Lagoon Management Plan (Draft BLMP).

To ensure there is full representation of all community and stakeholder feedback received during the consultation period to 30 June 2023, the current version will be updated to reflect what has been heard to date and include any additional findings from consultants once this work has concluded.

Council anticipates releasing Version 2 of the Draft Blue Lagoon Management Plan later in 2023 (October-December). More information will be made available on this webpage over the coming months.

Current resources

Draft Blue Lagoon Management Plan (Version 1)

Independent reports commissioned by Council referenced in the Draft BLMP available to view:


The Blue Lagoon area is of high ecological importance and socio-cultural value.  It is surrounded by residential use, a public park / playground, road and parking infrastructure and the popular Blue Lagoon beach.

The review and update of the original 2008 BLMP responds to the need to take a broad approach to managing the co-existence of the natural environment with multiple users, residents and stakeholders. The draft BLMP seeks to balance these different values and characteristics of all users, identifies risks and proposes recommendations for mitigation/adaptation measures to ensure there is sustainability for flora, fauna and communities.

It sets out an overarching framework for sustainable management in partnership with local communities and stakeholders, with the aim to ensure the Lagoon is managed in a way that protects its biodiversity and meets the needs of the community, now and into the future.

Naturally, the Lagoon has endured periods of dry and wet seasons. Over recent years, increased water levels in the Lagoon mean there has been a flourishing of biodiversity which is highly valued (both ecologically and aesthetically) by many in the community.

It is also known that during dry seasons, Blue Lagoon has been subject to fire, arson and vandalism, and has been used as a dumping ground.

During significant wet periods, private properties, Boat Park and Kannah Street have been impacted by floodwater and this poses significant risk.

The frequency of extreme weather events has resulted in Council having to react to mitigate impacts to surrounding recreation, beach and residential areas.

Implementing the BLMP will facilitate more sustainable actions to cope with future weather events, while seeking to improve measuring and monitoring of key environmental health indicators.

The BLMP nominates an operating budget allocation for staged removal of Cumbungi commencing 2023/2024. The BLMP envisions cumbungi will be removed and managed to prevent future infestation.

The BLMP references a review in 3 years, however, it is intended to be a living document that is flexible and adaptable to enable the activities and actions implemented under the BLMP to be assessed, re-evaluated and amended or new actions proposed at key milestones.

This includes Council taking into consideration stakeholders and local community feedback based on their ongoing investment in the care and maintenance of the Blue Lagoon Reserve and surrounding coastline.

As a wetland, Blue Lagoon has (and continues to be) a natural capture for water runoff and a filtration system.

The BLMP includes details on what has been investigated by Council as stormwater options to manage the risk of inundation and impacts to the receiving water. Stormwater has (and will) continue to find its way to the Lagoon given the topography and geomorphology. The Lagoon acts as a filter for sediments, Total Suspended Solids (TSS) and to decrease the nutrient concentration. Elsewhere in Australia other councils have invested heavily to create man-made lagoons to filter (biologically) water before entering waterways.

We are currently seeking an independent review of stormwater management options.  The recommendations from this review will be incorporated into the BLMP and redistributed for community consultation.

The Development Application (DA 5.2022.99.1) referenced within the BLMP is on hold pending the outcomes of the review and the separate Federal EPBC (Environmental Protection and Biodiversity Conservation) assessment process.

The DA is referenced in the BLMP for context only and to identify what studies have been used to develop the stormwater management proposal to date.

Stormwater management is one of a range of elements set out under the BLMP that contribute to ensuring the future protection of the wetland’s biodiversity.

The statutory process for the DA falls under the assessment requirements of the Planning Scheme. This is separate to the BLMP, however, the management plan can provide guidance to the planning authority. Updates on the DA status will be provided on the Council’s website, including when further statutory notification is to occur.

During the time of a peak flood, as per the Entura Stormwater System Management Plan (SSMP) modelling, the proposed DN600 outfall is capable of discharging about 300 L/s for 12 hours duration. The modelling only considered peak flow and not event volume. Significant additional investigation would be required of the catchment hydrodynamics to calculate the exact volume of water during a Q100 rainfall event (i.e. 1 in 100 year).

The proposed permanent stormwater outfall option will be considered as part of the independent review.

This is unlikely as their removal will be staged over time to enable plantation of suitable alternative native species. This will occur simultaneously.

Pine trees have established themselves over decades and provide important habitat for some of the fauna in the lagoon. Removing them completely in a short period of time is not considered best practice.

The BLMP considers the recommendations and actions identified in the Strategy to ensure alignment is achieved where possible.  In particular, with regard to access locations #42, #44, #45 and #46. The BLMP acknowledges the underlying principles of the Strategy including Principles 1 – 6.

The BLMP acknowledges maintenance and management is key to sustainable use of the foreshore. Council will continue to work with the State government to ensure suitable access to the Crown coastal reserve is provided.  Defined Blue Lagoon walking trails with regular inspections and monitoring will reduce, and ideally eliminate unauthorised access of the foreshore.

It has not been fully considered as a management practice due to the potential to cause major ecological impacts. This would require further expert investigation.

In the last few years, there has been confirmation of Red Handfish being located in the Sorell Municipality with greater community awareness around the conservation of the species.

As a critically endangered species, Council is working directly with major stakeholders including IMAS to facilitate protection, education and understanding of this species. Council and the community can play an important part in supporting the protection of the species. Further, the potential impact on the receiving waters from the proposed Blue Lagoon intermittent overflows is currently being assessed as part of the EPBC process.