Water Engineering

Burchills are currently engaged by the City of Gold Coast to provide specialist engineering services to support a footbridge upgrade Planning and Options Assessment. Burchills have undertaken site investigations, hydraulic study, civil and structural assessment, options analysis, construction costing, with the final deliverable being a Planning Report for the replacement of Coplick pedestrian bridge.

The bridge traverses the Tallebudgera Creek as Scotty Logan Lane, Tallebudgera Valley, and in 2017 the City determined that the structure had reached the end of its serviceable life and replacement was required.

Burchills undertook a detailed hydraulic impact assessment of 6 possible design options for the bridge, including possible refurbishment of the existing structure. 1D/2D coupled hydraulic modelling (TUFLOW) was used to test the impacts of the various design options, with 1D HEC-RAS modelling also undertaken to verify the study and gain an initial understanding of the hydraulic behavior of the bridges.

The hydraulic study was then packaged within a planning investigation that included a whole of life cycle costing analysis as well as a cost benefit investigation. The study was used by the City to inform their bridge replacement program, and is envisaged to form part of a Design and Construct tender package in 2019. Our scope also covered bridge engineering services to support a footbridge upgrade option assessment.  Burchills undertook investigations, structural design concepts, options analysis, design costings, and a structural planning report for the replacement of Coplick pedestrian bridge.

Burchills were engaged by Reece Milburn to complete a regional flood study of the Proserpine River catchment. The purpose of the study was to determine a defined 1% AEP flood level for a proposed development near the town of Proserpine. The project consisted of developing detailed hydrological and hydraulic modelling in URBS and TUFLOW.

Burchills were engaged by Toowoomba Regional Council to complete a drainage mitigation, forward planning study for the Kingsthorpe township.

The study was to build upon a collection of Urban Stormwater Master Planning (USMP) projects completed across the TRC LGA since 2015, which established strategic planning goals for stormwater capital works upgrades, hydraulic master planning, and some regional stormwater management and flood mitigation strategies.

The project consisted of detailed 1D/2D hydraulic TUFLOW modelling and 12D design to ensure the flood mitigation measures proposed within the original USMP are constructible, cost effective and practical, yet still uphold the hydraulic intent of the original modelling. The Burchills team has a strong understanding of not only hydraulic modelling, but detailed civil design and construction and is therefore uniquely suited to ensuring that conceptual hydraulic optioneering processes are able to be carried through to the detailed design and construction phase of a capital works delivery program. Following the Forward Planning phase of the Kingsthorpe Urban Stormwater Master Plan project, Burchills were also engaged to complete the detailed design and construction documentation for the various flood mitigation modules in the township of Kingsthorpe. The works included five (5) detailed design packages, detailed estimates and quantities, and detailed hydraulic assessment of the final designs. The Burchills team has a strong understanding of hydraulic modelling, as well as detailed civil design and construction documentation, which makes us uniquely specialized in the delivery of drainage mitigation works, from planning through to construction.

Burchills were recently engaged by City of Gold Coast to support the implementation of the stormwater drainage network capital works program within the Broadbeach catchment. Burchills was responsible for the Forward Planning phase of the program, where design options assessment and cost benefit analysis were completed for a number of problem areas within the catchment.

A number of design solutions were tabled for each problem area and investigated using 1D/2D TUFLOW modelling. The improvement to habitable floor flooding from each design was established to determine cost benefit. Constructability of the proposed infrastructure works was a key parameter to be considered in the proposed upgrade options, as well as rationalisation of the network, removal of infrastructure that traverses private property, and improved overland flow conveyance where possible. The work also required concept design and detail, to ensure that the proposed upgrade options were clear of other service/infrastructure clashes. After completion of the Forward Planning phase, the designs proposed with the highest cost benefit ratio moved into the Detailed Design and Construction phase.

In 2020 Burchills Engineering Solutions were engaged by the City of Gold Coast Council to undertake the conceptual design, modelling and mapping of the stormwater quantity components of the Local Government Infrastructure Plan (LGIP) for four catchments (Gin House Creek, Lower Coomera River, Currumbin Creek & Pimpama River).

The purpose of the project was to gain an understanding of where existing trunk stormwater infrastructure is unable to support future growth, and what additional infrastructure is required to service future development.

The performance of existing detention facilities, potential detention facilities (on-line and off-line) and the required trunk infrastructure sizing (pipes and channels) within the study areas were assessed for the current development scenario (2016) and in five-year increments from 2021 to 2041 as the ultimate development scenario. URBS hydrology models were built and calibrated to real events for the flows used for the hydraulics calculations. XPSWMM was used to complete the hydraulic analysis and to inform the concept design and sizing of future infrastructure.

The Breakwater development is located in Robina on the Gold Coast QLD. The masterplan envisages a lakeside community with over 2000 dwellings that includes the construction of large lakes that are well integrated into the natural landscape and responsive to the extensive constraints.

The project has adopted an innovative approach to designing a new residential community on the Gold Coast, presenting a consolidated and clear vision for the future Breakwater Robina community that capitalises on its position alongside the City of Gold Coast’s Principal Activity Centre of Robina.
The site sits on the largest floodplain in the Gold Coast Local Government Area, influenced by the Nerang River as well as multiple creek systems.

The site has multiple constraints including but not limited to extensive flooding, major earthworks including mass hauls, poor soils (marine clays), groundwater, localised overland flow, protected vegetation, acid sulphate soils, existing services that are at capacity, as well as sensitive neighbouring communities (school, hospital, residences, etc,).

Due to the number of constraints, and due to our extensive experience in dealing with multi-discipline projects, Burchills was appointed Lead Engineer for the project. We have successfully worked through solutions for the management of each constraint with various approval agencies, and multiple stakeholders, to form an overall development strategy that is cognisant to how each issue affects the other.

The management of these issues have also flowed through to construction. Earthworks for the site comprised over 2,000,000m3 of material across 100 hectares. Burchills was able to lead the development design process to overcome the ultimate design challenges, and also solve constructability issues associated with interdependent constraints during design and planning phases.