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Emerald Lifeline Implementation – Water Infrastructure Design Development Through 3D Modelling
The town of Emerald is supplied by two existing water treatment plants (WTP’s); the Opal Street WTP and East Nogoa WTP. The Opal Street WTP requires significant maintenance and upgrade works to ensure the ongoing reliability and compliance of the plant. Recent planning services identified the need for augmentation of existing pipework to allow the plant to be taken offline to enable these much-needed upgrade works. Further, the upgrade to the existing media filter outlet and chlorine dosing pipework was identified by CHRC as priority works for the site.
AECOM utilised 3D digital survey and modelling technologies to undertake the detailed design of these works. Due to the nature of the brownfield site, AECOM used a combination of point cloud survey of the area around the existing filters and a topographical feature survey for the remaining site to complete the design services. A 3D model was developed, to ensure conflicts with surrounding pipework and structures were avoided during the design stage.
From the point cloud survey, a 3D model of the proposed network upgrades was created utilising AutoCAD Civil 3D. The model was created with pipes and fittings based on manufacturer’s dimensions and where possible, the manufacturer-supplied individual 3D fitting models. This maximised the accuracy of the design by representing all pipework and fittings in the model as they would be constructed on site.
Use of these tools enabled the ability to visualise and detail complex fitting arrangements, avoid clashes, and optimise constructability prior to construction. Due to the accuracy of the models, greater confidence was achieved in the design. As a result, construction cost and program risks were reduced.
Our continued collaborative effort with CHRC may introduce further opportunities for 3D modelling, namely our commitment to the sustainable legacy we have in relation to asset management through extended design life of infrastructure and paperless drawing production. As the water industry matures in its use of 3D modelling, this project represents a practical and scalable approach for water utilities that can be applied on a wide range of projects.
Opal Street Water Treatment Plant – Flanged Pipework
Central Highlands Regional Council (CHRC) is a local government located in Central Queensland, Australia. The region encompasses an area of around 60,000 square kilometres and is home to approximately 30,000 people. CHRC is committed to continuous improvement, a sustainable future and efficient investment in its communities. CHRC provides a range of vital services for its residents and businesses and is committed to further developing its economic, sustainable, and social infrastructure to meet community needs and maximise and enhance community wellbeing.
The town of Emerald, located within the CHRC region, is supplied by two existing water treatment plants (WTPs); the Opal Street WTP (installed in the early 1970’s) and the East Nogoa WTP (installed in 2015). Currently, the Opal Street WTP supplies west Emerald and East Nogoa WTP supplies east Emerald with no ability to feed both west and east Emerald from one plant.
The Opal Street WTP requires significant maintenance and upgrade works to ensure the ongoing reliability and compliance of the plant. Recent planning services completed by AECOM for CHRC, identified the need for augmentation of existing pipework at the Opal Street WTP to allow the plant to be taken offline to undertake much-needed upgrade works. Further, the upgrade to the existing media filter outlet and chlorine dosing pipework was identified by CHRC as priority works for the site. These augmentation and upgrade works need to be undertaken whilst continuing to provide potable water to the community of Emerald.
To allow for the reconfiguration works, AECOM in collaboration with CHRC, utilised 3D digital survey and modelling technologies to undertake the detailed design section of this work.
Challenges of the existing site
Having completed the concept and preliminary design prior to the engagement for detailed design services, the team were aware of several challenges and complexities within the site, including: • Space constraints around existing buildings, filters, clarifiers, and pipework. • The majority of the connections into the existing network were above-ground with little to no flexibility due to flanged joints and availability of space between existing infrastructure (refer Figure 1). • Limited available shutdown times (maximum 8 hours) and limited operational flexibility within the plant due to water demand.
To further reduce potential conflicts and risk during construction, the team considered an alternative 3D approach. These complexities involved in completing the design at the Opal Street site, prompted the 3D approach.
The concept and preliminary designs were based on topographical feature survey and buried services location (potholing). However, throughout the design development, it was found that the survey data within and around the filters (pipework and appurtenances), particularly the above-ground network, was not sufficient for the design to be progressed.
Data collection and interpretation
Due to the nature of the brownfield site, AECOM and CHRC opted to use a combination of point cloud survey of the area around the existing filters and the existing topographical feature survey for the remaining site to complete the detailed design services. The point cloud survey ensured maximum locational accuracy of the existing filters, above-ground network and most importantly the existing flanges for the proposed connections.
A local surveyor was engaged to complete the 3D scan in and around the filters. Following the physical site scan, the automatically georeferenced
3D Model Development
Filter Manifold Pipeline 1
point cloud data was made available to the AECOM engineering team. With approximately 25 million points per scan, over 50 scans were provided (i.e., 40 GB of raw data). Increased computational power was required to process the raw point cloud due to the extremely large data set associated with the point cloud data.
The proximity of the thousands of individual points within the point cloud allowed the visualisation of a 3D surface. Although there were no attributes assigned to each point, the scan was completed with red-green-blue (RGB) colours to match the colours of existing infrastructure on site which enabled the visual identification of each infrastructure component.
3D model development
The 3D point cloud file was imported into AutoCAD Civil 3D as the base file. From the point cloud, a 3D model was created of the existing and proposed network upgrades. The model was created with pipework and appurtenances based on manufacturer’s dimensions and where available, the manufacturer-supplied individual 3D fitting models. This maximised the accuracy of the existing and proposed design by representing all pipework and appurtenances in the model as they exist and will be constructed on site (refer Figure 2). At the time of the initial model build it was found that the manufacturer’s database for fittings was limited, this has significantly developed since. Manufacturers were more than willing to assist in providing models of their fittings for the model development allowing the designers to further build the internal database and provide additional efficiencies for future projects.
Following the development of the existing site infrastructure within the model, calibration of the model to onsite points was undertaken. The 3D point cloud survey has a theoretical accuracy of +/- 1 mm however the accuracy of the scan was influenced by the following: • Constraints at the site (i.e., space between filters, buildings, pipework, etc. for the flight path).
Acknowledgements
The author would like to acknowledge the following for their contributions this project to date:
Marvin Pacheco, Acting Manager Water Utilities, Central Highlands Regional Council
Andrew Sheales, Coordinator Engineering Water Utilities, Central Highlands Regional Council
Abby Carolan, Team Lead - Water, Rockhampton, Technical Practice Lead – Civil, ANZ, AECOM Australia Pty Ltd
Tim McMaster, Senior Technical Officer, AECOM Australia Pty Ltd
Lindsay is a Civil Engineer with over four years’ industry experience in the local government and private sectors. Lindsay has been involved in various projects across transport, hydrology and hydraulics, water infrastructure, construction administration and civil infrastructure. Eager to experience a wide range of projects, Lindsay worked with Gladstone Regional Council as an undergraduate where she completed her final year engineering project in the water and wastewater sector. Beginning with AECOM as a graduate in the Water Resources team in 2018, Lindsay has since transferred to the Water Infrastructure team to further broaden her experience.
Fun Facts: • I love sport (after hours you’ll find me on a field of some sort) • Once upon a time, I wanted to be a mathematician • I have two younger sisters, one of which is in the Navy, the other who works for the local Council.
