DesignFlow

Urban Lake Management
Townsville Constructed Lakes Policy and Design Guideline, QLD
Client: Townsville City Council
DesignFlow developed a Constructed Lakes Policy for Townsville to define the design requirements and regulate construction of lakes in the Townsville area. Lakes built in the dry tropics region of Townsville operate under a range of challenging climatic conditions and maintaining a healthy water body can be difficult to achieve. To support the Constructed Lakes Policy DesignFlow developed a Constructed Lakes Design Guideline, which provides background information on lake health considerations and a step by step design procedure to meet Council requirements to support a Development Application involving a lake. The guideline can be downloaded from:
http://www.townsville.qld.gov.au/resident/planning/Pages/forms.aspx
 
Townsville Constructed Lakes  

 
Review of Shallow Lake Ecology and Detention Time Criteria
Client: Water by Design
A scientific review of shallow lake ecology was undertaken to access the potential effectiveness of manipulating lake retention times to reduce the risk of cyanobacterial growth in constructed lakes. The review included:
The review concluded that the manipulation of urban lake detention times using the current probabilistic method represents a precautionary approach at best, and that no strategy will guarantee full protection against cyanobacterial blooms. The control of cyanobacterial biomass via lake retention time design criteria will be most likely facilitated by constant flushing of cyanobacterial biomass from the lake system, whereas control of cyanobacterial biomass via episodic washout (stormwater runoff) is unlikely to provide acceptable management of cyanobacterial blooms.
 
Townsville Constructed Lakes  

 
Moreton Bay Lakes Prioritisation, QLD
Client: Moreton Bay Regional Council
Constructed and natural lakes within the Moreton Bay Regional Council area are under considerable pressure due to increasing urban development and historical land uses. As a result, many are in a degraded condition, or are at risk deteriorating in the future. Historically, with the absence of design, construction and management guidelines, many lakes were poorly designed and / or not adequately maintained. This has often led to a rapid deterioration of water quality and aesthetic values, failure of hydraulic structures and infestations of noxious weeds. In recognition of its commitment to gain an increased understanding of urban lakes located on land under its control Council commissioned Limnologic and DesignFlow to identify, characterise and prioritise lakes situated on Council owned land and to develop a Management and Rectification Framework for very high priority lakes. The investigations involved: Of the 213 Council owned lakes, 22 were identified as very high priority requiring management and/or rectification.
 

 
Gold Coast Regional Botanical Gardens, QLD
Client: Gold Coast City Council
In collaboration with DBI Landscape and KN Group Consulting Engineers, DesignFlow has developed a detailed design for the Gold Coast Regional Botanic Gardens that delivers a science-based and adaptive solution for a highly degraded urban lake in the public realm. The design provides a safer and more enjoyable system with great opportunity for interpretation and education through the botanic and water features offered though the design.
 
botanical_gardens  

 
Quiet Lakes Water Quality Management Plan, VIC
Client: Melbourne Water
A water quality management plan to manage the growth of cyanobacteria and improve the health of the Quiet Lake system was developed. The water quality management strategy reflects contemporary scientific understanding of shallow lake ecology and considered a range of issues including aquatic macrophytes, salinity management, lake residence times, nutrient management and the management of exotic fish species. The recommended water quality management strategies considered stakeholder input and were selected on the basis of expected outcomes, efficiency, long term sustainability, cost and ease of implementation.
 
 
Quiet Lakes  

 
St Peters Billabong, SA
Client: Adelaide & Mt Lofty Ranges Natural Resource Management Board
DesignFlow reviewed the current operation of the St Peters Billabong with a view to develop options for improved performance and health. Field investigations included water quality testing, sediment analysis and lake bathymetry. The review identified poor lake health as a result of high organic inputs. Further investigation quantified groundwater quality and inputs to the Billabong via the use of a salt water balance. Proposed remediation actions included de-silting, decommissioning of the GPT, reducing drainage inflows, improving the inlet sediment capture zone and conversion of the Billabong to a groundwater dominated system.
 
DesignFlow chaired a steering group comprising AMLRNRM, City of Norwood, Payneham and St Peters and the Friends of the Billabong.
 
St Peters Billabong  

 
Pine Rivers Park, QLD
Client: Moreton Bay Regional Council
In collaboration with Council, DesignFlow developed a conceptual design to retrofit a section of the Pine Rivers Park Lake with a stormwater treatment wetland to improve lake water quality and the quality of stormwater discharged to the Pine River.
 
The wetlands will be integrated with recreational open spaces, parkland and neighbourhood pedestrian /cycle networks to create an integrated open space system that provides significant social, environmental, & recreational benefits to the wider community.
 
Interpretive & educational tools will be placed around the wetland and lake systems to enhance and foster an interactive learning experience.
 
The conceptual wetland design was preceded by an extensive site audit including: water quality sampling and analysis, sediment sampling and analysis, site characterisation (site character, site use, natural features, management issues), detailed hydraulic and catchment modelling.
 
pine_river5  

 
Bundaberg Botanical Gardens, QLD
Client: City of Bundaberg
The lake system at the Bundaberg Botanical Gardens regularly experience algal blooms and other water quality problems as a result of urbanization in the catchment and from organic matter deposited by birds. DesignFlow conducted a detailed site review and developed strategies to improve the environmental health the lake system at the Bundaberg Botanic Gardens.

Recommendations to improve the health of the lake system included:  
bundaberg3  

 
Spavin Lake Water Quality Improvement Plan, VIC
Client: Hume City Council
DesignFlow developed a water quality management plan to lower the risk of cyanobacterial growth within Spavin Lake. A detailed site analysis identified several lake attributes - lack of macrophytes, long hydraulic residence times, high turbidity and inflows with high nutrient concentrations - as the likely factors contributing to the nuisance growth of cyanobacteria within the lake. Management options to improve water quality within the lake included modifying the lake bathymetry and volume, retrofitting the lake with a stormwater treatment wetland system that can also be used to recirculate lake water during high risk periods for cyanobacterial growth and re-establishing macrophytes throughout the lake.

The management plan also addressed other lake management issues such as:  
 
Spavin Lake 1  

 
Lake Inspection and Audits
Client: Local Government and Private Consultation
Given our technical understanding of lake design and management, DesignFlow has undertaken numerous lake design and management audits for local authorities and private developers including:
 
Vintage Lake
Client: Tweed Shire Council
Vintage Lakes and the associated Banora Point western drainage scheme, has a long history of waterbody and water quality related issues. DesignFlow were asked by Council to cast a fresh set over eyes over the lake and drainage system to define management options which reduced nitrogen levels into the Tweed River system and reduce the asset management cost for the internal lakes. The work provided a range of short, medium and long term management actions which Council are implementing.
 
Vintage Lake 1  

 
Lake Hugh Munz
Client: Gold Coast Shire Council
Lake Hugh Muntz is a freshwater lake on the Gold Coast which has been used for a number of recreation purposes by the local community including swimming. The lake is a lense into the local groundwater with very little catchment. The water quality of the lake has been gradually decreasing through nutrient accumulation and increases in salinity. As part of their review of Lake Hugh Muntz, Gold Coast City Council asked DesignFlow to provide specific lake management advice.