Abstract
Purpose: The Virtual Design Construction (VDC) approach transforms infrastructure projects, especially those involving collection systems, showcasing its worth throughout every stage of execution, starting from planning and design through to construction. Benefit: This presentation serves as a primer for utilities, consultants, and contractors, offering insights into the VDC tools that can significantly enhance the execution of a collection system project. It also showcases case studies and highlights instances where these tools and processes have been successfully applied in DeKalb County's capital improvement collection system projects. DeKalb County and River To Tap (R2T) excel in utilizing integrated VDC techniques across the entire span of a collection system project. This allows for precise monitoring of progress against anticipated goals. The digital assets generated in the planning, design, and construction stages smoothly transition into operations, guaranteeing the peak performance of the infrastructure assets. Integrated VDC techniques utilized throughout multiple phases of recent collection system projects: - Drones to collect aerial photogrammetry for routing analysis and optimization (Planning, Design) - Laser scanners to develop point clouds of existing facilities and structures (Design) - 3D models transitioned into REVIT and Civil 3D environments to generate contract documents (Design, Construction) Reverse Gwinnett Flow Project: The Reverse Flow Project was initiated to establish a regional conveyance solution along the boundary between DeKalb and Gwinnett Counties, redirecting current sewer flows from Gwinnett County back to DeKalb County. The project encompassed the design of several lift stations (1250gpm, 450gpm & 450gpm), 31,000 LF of 8'-12' force main, 6,000 LF of 18' gravity sewer, and the decommissioning of several lift stations. Drones played a pivotal role in this phase by identifying optimal lift station sites along the county border and refining conveyance routing through elevation high point determinations, all while minimizing impacts on property and roadways. The collected aerial photogrammetry provided crucial data, result in the development of a conceptual flow path, ultimately increasing pumping and pipeline independence. Identifying three lift station sites, three force main routes, and a common high point discharge location presented a significant search area. Early aerial photogrammetry using drones proved invaluable in this process. As the project progressed from planning to design, laser scanners were deployed to create point clouds of existing lift stations earmarked for upsizing, as well as those to be decommissioned. This data was integrated into the Civil 3D design environment to facilitate decommissioning plans and harmonize proposed lift station design and sequencing. Approximately 7 miles of pipeline were designed in three dimensions as part of a comprehensive pipe network in Civil 3D. To minimize property impact and reduce required easements, the pipeline was routed along less frequented roadways, which introduced potential utility conflicts. Consequently, modeling the pipeline and utility crossings in the live three-dimensional environment of Civil 3D was pivotal. The pipe model, instrumental in creating contract documents, could be maintained throughout construction and ultimately transferred as an asset to the GIS, Operations, and Maintenance teams. This project has reached 100% design stage. The Design Build Gravity Sewer Rehabilitation (DB3): The DB3 project entailed the enlargement of approximately 29,000 LF of sanitary sewer lines (ranging from 8' to 36'). VDC played a pivotal role in streamlining the survey process by employing drones to swiftly capture existing surface data along the sewer route. During the construction phase, VDC once again proved its effectiveness when unexpected challenges emerged behind an old, abandoned gas station. The enlargement of the existing pipe revealed unforeseen soil conditions, compounded by an eroding bank supporting the disused gas station parking lot. In response to this urgent situation, laser scanning was deployed to devise solutions, including the implementation of a gabion wall to reinforce the eroding bank. Ultimately, a realignment across the creek, away from the abandoned gas station site, was chosen as the optimal resolution. The design phase of this project is complete, while the construction phase has progressed to 90% completion. Shoal Creek Trunk Sewer Project: The Shoal Creek Trunk Sewer Project aimed to enhance the capacity of approximately 13.3 miles of gravity sewer. With nearly five decades of service, the existing pipeline faced challenges with infiltration and inflow due to its aging state and the population surge since its initial installation. This pipeline plays a pivotal role in DeKalb County Department of Watershed Management (DWM)'s comprehensive wastewater collection and transmission system. Shoal Creek has expanded, exposing the aging gravity sewer along its banks. Residences, structures, and park amenities have been constructed atop the pipeline, making maintenance and replacement efforts challenging or even impractical. Additionally, most of the creek crossings for the aging pipeline were aerial, as the pipe was installed at shallow depths along the corridor. This presented an opportunity during the design phase to increase the capacity and reliability of the pipeline by exploring options to go beneath the creek. The process of evaluating existing factors along the pipeline and determining an optimal route for an upsized line, while considering present conditions, was successfully executed within the 3D environment of InfraWorks. This platform provided a comprehensive view of existing conditions, the current pipeline, and the proposed pipeline. The visualization of site, building, and pipeline data facilitated innovative discussions during the preliminary design stages, enabling walkthroughs and renderings of the project. This resulted in detailed inquiries, suggestions, and discussions that wouldn't have been possible with a traditional 2D drawing review. Moreover, it allowed the team to focus on specific areas along the pipeline presenting design challenges and facilitated real-time analysis of potential solutions. These solutions were then integrated into the 3D pipe model and utilized in the development of the contract documents. This project has reached 90% design stage. Conclusion: Virtual Design and Construction (VDC) technologies and methodologies have firmly established themselves as valuable tools for collaboration within the Architecture, Engineering, and Construction (AEC) sector. The partnership between the R2T team and DWM has identified various strategies for leveraging VDC in the execution of collection system projects. Whether in the stages of planning, designing, or constructing, VDC has proven its ability to provide Utilities with crucial resources, enabling them to proactively navigate the intricate landscape of cost and schedule management amid challenging market and regulatory conditions.
This paper was presented at the WEF Collection Systems and Stormwater Conference, April 9-12, 2024.
Author(s)A. Johnson1, A. Torres2, S. Criminski3, H. Barnes2
Author affiliation(s)DeKalb County 1; R2T 2; AtkinsRealis 3
SourceProceedings of the Water Environment Federation
Document typeConference Paper
Print publication date Apr 2024
DOI10.2175/193864718825159407
Volume / Issue
Content sourceCollection Systems and Stormwater Conference
Copyright2024
Word count17