A Jacksonville Electric Authority work crew takes GPS readings on a water main as it is being installed. By gathering data immediately, as-builts are more accurate. Photos: Reynolds, Smith and Hills Inc.
Once accuracy is confirmed, the points are exported into an AutoCAD file format where they are layered on the original construction plans. The as-built GPS data are compared against the construction drawings. If there are discrepancies beyond accepted tolerance levels, the changes are verified and accepted by the inspector. If the pipe installation exceeds accepted tolerances, it is identified for reinstallation.
This new process allows for real-time quality assurance and quality control of the features installed while the contractor is still on the job. Quality control includes bi-monthly preparation of draft as-built plans for each project. The data collector, contractor, inspector, and the project manager meet to review drafts, and markups are then created.
When construction is done, the project's final as-built plan is submitted both in hard-copy form and in AutoCAD format. The project's GIS shapefiles are given to the records department to be included in the authority's enterprise utility geodatabase system. Previously, the records department would have to take each sheet of the as-built plans and digitize the utilities before adding it to the geodatabase, a process that could take anywhere from two hours to two days per page depending on the complexity of the plans. The delivery of plans in GIS shapefile format are easily added to the geodatabase, an unexpected, but valuable time- and money-saving benefit.
Contracts are being closed out sooner, which releases funds for other projects, which increases the customer service level of the Jacksonville Electric Authority.
Plus, collecting the data this way doesn't cost the authority more. Close-out periods are shortened so administrative costs are cut, data are imported directly into the GIS database, drawings are delivered in multiple formats for contractors and inspectors, and turnaround times for the as-built plans is quicker and more accurate.What does as-built really mean?
Contractors produce as-built drawings and compare them with the original design documents to identify any changes made during installation that could affect the facility's performance. Discrepancies between the original bid-set drawings and the installation are corrected before moving into the building. Problems can include an incorrectly marked pipe or a motor supplied with the wrong voltage. Ideally, the “as-built” verification is performed several times during construction, so that conflicts between design and installation are resolved with minimal effect on the project schedule.
— Capobianco is a GIS analyst for the Transportation and Infrastructure Programs of Reynolds, Smith and Hills Inc.