Issues and Prospects of Digitalizing Civil Engineering As-Built Management That Municipal Staff Should Know

In recent years, the digitalization of construction sites has rapidly advanced, and the use of ICT technologies represented by the Ministry of Land, Infrastructure, Transport and Tourism-led *i-Construction* is becoming commonplace even in civil engineering work. In particular, civil engineering as-built management (the construction management process that verifies whether completed structures conform to design shapes and dimensions) is a field where dramatic efficiency gains and sophistication can be expected through digital technologies. This article explains in plain terms for municipal staff (client-side engineers in cities, towns, and villages) the current status, challenges, and mid- to long-term prospects of digitalization in civil engineering as-built management. We organize the hurdles to field implementation and administrative-specific barriers, and propose future directions and concrete first steps.

What is civil engineering as-built management? Traditional methods and the trend toward digitalization

Civil engineering as-built management is the process of verifying and recording whether structures such as roads and bridges completed by construction are built according to the standards specified in the design documents. In public works the client (the administration) specifies as-built management standards, and the height, width, thickness, etc. of the completed structures are measured to demonstrate conformity. Traditionally, as-built verification was performed by manually measuring key points on the construction site with tools such as tape measures, leveling rods, and spirit levels, and compiling the measurement results on paper records or drawings. For example, in road works the width, thickness, and elevation of the completed roadbed were measured manually at multiple locations and compared against design values. This traditional method required a lot of manpower and time, and because the number of measurable points was limited, it was difficult to comprehensively grasp the entire structure. Manual measurement can only verify “points,” so there is a risk of overlooking portions that slightly differ from the drawings and being flagged in later inspections, and human errors such as forgetting to photograph buried items and leaving no record also tended to occur.

To solve these problems, digitalization of as-built management is currently attracting attention. Specifically, methods that use 3D point cloud data (high-density spatial measurement data composed of many measurement points) obtained from drone aerial photography or ground-based laser scanners to verify and record as-built conditions are being adopted. Using 3D scanners or photogrammetry techniques allows non-contact measurement of entire structures in a surface- and volume-based manner, rather than measuring limited points as before, enabling comprehensive capture of as-built conditions. In addition, the process from measurement to drawing can be completed on digital data, improving the efficiency of record creation and preventing human error. As part of the *i-Construction* policy promoted by the MLIT since around 2016, such 3D as-built management has been fully introduced in directly managed projects. For example, ICT earthworks involve a series of digital construction management processes from pre-construction 3D survey, to machine guidance during construction, to post-completion 3D as-built management. ICT utilization is becoming standard in nationally managed projects, and by fiscal 2023 ICT construction (including as-built management) had been implemented in about 87% of nationally managed civil engineering works. Furthermore, the MLIT has set a goal to “in principle apply BIM/CIM to all public works except small-scale ones by fiscal 2023,” and as-built management based on digital 3D models is expected to become an increasingly industry-standard practice.

Introduction status in municipalities and regional disparities

While digital as-built management is advancing under national leadership, the adoption status at the municipal (prefectures, cities, towns, and villages) level varies. Large cities and forward-looking municipalities have started to adopt ICT construction in step with national moves, but in many small local municipalities traditional methods still prevail. Currently, prefectures and government-designated cities are gradually increasing adoption of ICT earthworks, and some are taking steps toward introducing digital technologies, such as preparing trial guidelines and designating model projects. However, at the town and village level there is significant variation in response, creating a gap between municipalities that are proactive about digitalizing as-built management and those that are not.

One reason for this gap is institutional immaturity. Because the legal status of digital measurement data and electronic submission guidelines are not unified, each municipality has different standards for ICT-utilized projects. For example, in some municipalities 3D as-built management is mandatory for contractors, while in others manual methods remain the standard; there are cases with completely opposite approaches. The lack of unified standards causes inconsistent adoption conditions across municipalities, which in turn delays nationwide diffusion.

That said, pioneering cases in rural areas are gradually increasing. For example, Yamanashi Prefecture equipped all civil engineering offices with 3D point cloud processing systems in 2022 and began full-scale deployment of point cloud data utilization in prefecture-commissioned works. In mountainous Yamanashi, where terrain is steep and small-scale projects are common, the prefecture has focused on the spread of flexible ICT construction using compact equipment and is promoting extensive point cloud utilization according to field needs. In a government-designated city example, Chiba City has provided employee training that lets staff experience as-built measurement with 3D scanners and trial electronic submission using point cloud viewer software, advancing preparations on the client side (administration) to accept digital deliverables. As clients such as municipalities begin to set up such environments, contractors feel more secure adopting new technologies, creating a virtuous cycle that promotes ICT use across the region.

On the other hand, many towns and villages say they “lack the sense of urgency compared to the national government or large municipalities” or “feel uneasy because there are no nearby examples.” The next section delves into concrete challenges encountered when municipalities attempt to introduce digital as-built management.

Challenges in introducing digital as-built management (field-level issues)

When a municipality attempts to step into digitalizing civil engineering as-built management, there are various field-level challenges and barriers, as outlined below.

• Introduction costs and budget constraints: Purchasing or renting ICT equipment such as 3D scanners, high-precision GPS, and drones entails substantial costs. For small municipalities, budgeting hurdles are high, and the burden of initial investment is a major deterrent to adoption. In addition, introducing new technologies requires training costs and ongoing operational expenses, so there are cases where concerns about long-term cost-effectiveness arise.

• Lack of ICT personnel and skills: Operating digital as-built management requires specialized skills such as 3D surveying, point cloud processing, and CAD software operation. However, few local government employees are well versed in these ICT technologies. In municipalities with few young engineers and advancing aging, training personnel who can handle new IT tools lags behind, raising concerns that systems will become “unused treasures” because “there is no one who can operate them.” Lack of training opportunities for existing staff and difficulty hiring immediately effective specialized personnel are also issues.

• Contractor capability: Many local construction companies handling public works are small and medium-sized enterprises that may not have the capacity to equip expensive ICT devices or assign specialized operators. Even if the client requires digital as-built management, the contractor side may lack the necessary systems (equipment and personnel), creating a barrier. Contractors may also avoid digital measures due to concerns that “digitalization will only increase workload” or “unfamiliar tasks will disrupt the site.” There are also real problems where both client and contractor field personnel are unfamiliar with electronic submission standards and CAD drafting rules and cannot cope.

• Lack of understanding within the municipal office and siloed departments: Promoting digitalization requires organizational consensus and support, but entrenched views like “there is no precedent” or “paper is more reassuring” remain. Budget requests may not pass without understanding from management or related departments, and information policy departments may impose security constraints. Furthermore, since traditional inspection flows and document management rules are premised on paper, there is no unified internal policy on how to handle digital data, and delays in developing cross-sectional rules can become a bottleneck on the ground.

• Restrictions on cloud usage: While cloud storage and online viewing systems are convenient for handling point clouds and electronic drawings, some municipalities cannot freely use cloud services due to information security or network constraints (e.g., LGWAN). Strict restrictions on office PC internet access or prohibitions on storing data on external clouds make it difficult to share and store digital data smoothly. Even if an on-premises server is prepared, the costs and management burden are substantial, often resulting in USB memory sticks or CDs being used and paper being kept in parallel—an ironic outcome.

As shown above, unless issues across equipment, personnel, organizational structure, and IT infrastructure are addressed, it is difficult to smoothly introduce digital as-built management on construction sites. But what specific barriers exist around “deliverable transfers” and “data storage”?

Hurdles in electronic submission of deliverables and drawing data storage

An often overlooked aspect when introducing digital technologies is the electronic submission of deliverables (final documentation) and the data storage mechanism. Even if 3D data are collected on site, if the deliverables cannot be properly submitted and stored, it cannot be called a true DX (digital transformation). However, municipalities face particular hurdles in electronic submission and electronic preservation.

First, electronic submission guidelines and CAD data formats differ between municipalities, imposing a heavy compliance burden on contractors. While a unified electronic submission system based on CALS/EC has been developed for national projects since the 2000s, at the municipal level there are cases of unique operational rules or parallel requirements for paper and electronic submissions. There are also complaints that “even if we submit electronic data, the office just prints it and stores it on paper,” leading contractors to feel that it “only increases workload without benefits.” Municipal staff themselves may be unaccustomed to handling CAD drawings or point cloud data and may be perplexed by “being able to visually check paper but finding it hard to inspect data” or “files are too large to open.” As a result, a hollowing-out occurs where “3D measurement is done on site but the final deliverable is submitted as 2D drawings.”

Furthermore, a mechanism to preserve and utilize submitted electronic deliverables over the long term is also a challenge. Paper drawings can be bound and stored in archives for near-permanent access, but digital data face many risks such as format obsolescence, physical media degradation, and data migration during system upgrades. Municipalities without sufficient IT budgets or personnel tend to “burn CDs for storage” as a stopgap, raising concerns that valuable electronic data will not be effectively used in the future. In practice, there are cases where electronic deliverables become buried because they are not handed over with coordination to maintenance departments.

Overcoming these hurdles requires municipality-wide rule-making on electronic submission and staff training, as well as consideration of national support measures and standardized tools. For example, actively using an electronic submission checking system provided by an MLIT-affiliated public interest corporation or CALS/electronic submission support services deployed by prefectures can be effective. It is also important to adopt a perspective that the received data should be used for future maintenance and asset management, creating mechanisms to “leverage the data next time” rather than merely storing them. This point is discussed further in the next section on prospects.

Mid- to long-term prospects opened by digitalization

Despite many challenges, advancing digitalization of civil engineering as-built management will undoubtedly bring significant benefits to administrative work and social infrastructure management. From a mid- to long-term perspective, the following expansions of use are expected.

• Remote site attendance (remote inspection and witnessing): Remote attendance, currently being trialed by the national government and some municipalities, enables construction inspections and witnessing to be done from the office in real time without visiting the site. If high-resolution images and 3D-scanned as-built data can be checked over the Internet, travel time for staff will be reduced and sites in depopulated or remote areas can be handled efficiently. This is promising as a countermeasure against labor shortages, and once necessary institutional arrangements are made, practices such as checking and approving as-built conditions online may become commonplace.

• Rapid disaster recovery response: In the event of a large-scale disaster, surveying damaged areas and designing restoration works is a race against time. Digital as-built measurement using drones and mobile devices is attracting attention as a method to grasp damage quickly without sending people into dangerous sites. For example, aerial photography immediately after a disaster can be used to create 3D models for rapid calculation of collapse volumes and planning temporary recovery. In practice, Fukui City early introduced a surveying system that combines smartphones and GNSS for disaster recovery sites, enabling a single staff member to safely measure dangerous slopes and thereby speed up initiation of restoration works compared to conventional methods. Such use of digital technologies can significantly streamline disaster response from initial action through recovery and reconstruction planning.

• Easier explanations to residents: 3D data and completed models obtained from as-built management can also be used as explanatory materials for local residents. Construction content that was difficult to convey with conventional 2D drawings or photos can be intuitively understood by showing completed images in 3D. For example, in bridge replacement projects, presenting a 3D comparison of old and new structures or visualizing a completed road in a VR-like format at public briefings can greatly enhance residents’ sense of reassurance and acceptance. Digital as-built data can thus become a tool that connects the administration and local residents as an asset.

• Linkage to maintenance management and asset registers: Digitized as-built information is useful for post-construction maintenance and public asset registry management. For example, importing precise 3D survey data obtained from as-built management into road and bridge maintenance management systems enables its use for post-completion inspections and repair planning, or directly reflecting as-built data in fixed asset registers to refine asset information. Currently, data are often siloed between construction and maintenance departments, but in the future, integration with BIM/CIM models and GIS will enable infrastructure management across the life cycle. Seamlessly linking electronic deliverable data with local public accounting (fixed asset registers) and effectively using the data after project completion will lead to genuine DX.

Thus, digitalizing civil engineering as-built management is expected to produce wide-ranging effects beyond mere measurement efficiency, improving administrative service quality and contributing to future smart city initiatives. In the mid to long term, combined with advances in digital technology (such as AI-based automated inspection and real-time data sharing via 5G communications), more advanced, safer, and more efficient infrastructure development and management will become possible. Toward that future, what should municipal staff start doing now? We conclude with some practical steps.

Steps toward introduction and good examples from other municipalities — start with simple measurements

Even if the benefits of digital as-built management are understood, you may wonder “where exactly do we start?” Below are steps for municipalities to gradually introduce digital practices and some illustrative examples from other local governments.

1\. Small-scale pilot implementation: There is no need to introduce full ICT construction across all sites at once. Start by trying digital technologies in just surveying and as-built management on a trial basis. For example, target small-scale road improvement or retaining wall works and try as-built measurement by drone photogrammetry or use electronic small blackboards (photo management) on tablets. Initially, accuracy verification and comparison with conventional methods are necessary, but “trying it first” accumulates on-site knowledge. Once you have track records, it becomes easier to gain internal support for the next step.

2\. Share knowledge through staff training and information exchange: Organizational learning is as important as training individual staff when introducing new technologies. Actively investigate other municipalities’ best practices and, where possible, conduct site visits or exchanges among responsible personnel. Examples such as Yamanashi Prefecture, Chiba City, and Fukui City mentioned earlier are instructive. Sending staff to seminars hosted by national research institutes and construction industry groups to learn the latest ICT utilization cases and know-how is also effective. Holding internal study sessions to inform not only field staff but also decision-makers and related departments about the significance and effects of digital as-built management helps create cross-organizational support.

3\. Select and use tools appropriate for introduction: On-site ICT tools are not all expensive, large-scale equipment. Recently, easy-to-introduce simple measurement solutions have appeared. For example, using the technology called “LRTK,” which combines a smartphone with a compact GNSS receiver, allows centimeter-class high-precision positioning and point cloud measurement (cm level accuracy (half-inch accuracy)) with just a smartphone instead of dedicated surveying instruments. Since you can scan shapes simply by walking the site, tasks that previously took half a day for surveying can be completed in a short time, greatly reducing personnel. In Fukui City, smartphone surveying technology (LRTK Phone) was used at disaster sites, achieving a dramatic improvement in speed of situational understanding compared to conventional methods. Such low-cost solutions compared to dedicated equipment provide a practical first step for municipalities trying digital as-built management for the first time.

4\. Accumulate small successes and expand: Based on the effects and lessons from initial trials, gradually expand target projects and usage scope. For example, in the first year introduce ICT only for as-built management, and if successful, plan a roadmap to expand to ICT-equipped machinery for automated construction or BIM/CIM utilization in subsequent years. The key is to start small, verify results, and run PDCA cycles to connect to the next step. Accumulate decision-making data such as “this area is effective” or “this isn’t cost-effective,” and explore a digitalization approach tailored to your municipality’s circumstances.

Finally, to municipal staff who are also civil engineers: digitalization is not a threat but a powerful tool that can reduce field workload and help ensure quality. With national support, even small, steady adoption of new technologies can lead to workstyle reforms for staff and revitalization of the regional construction industry. Why not begin a small-scale digitalization from something close at hand? Going to the site with a smartphone and a compact GNSS in hand—that first step could lay the foundation for evolving municipal civil engineering administration to the next stage.