8 Items to Check Before Handling Road Ledger Attached Maps in CAD

The maps attached to the road ledger are important documents that organize, as drawings, the information necessary for road management—such as road areas, road widths, boundaries, road facilities, items occupying the roadway, and roadside conditions. Paper drawings and PDFs of these road ledger maps, when made usable in CAD, make it easier to edit, search, overlay, manage update histories, and share with stakeholders. On the other hand, because these maps are not merely drawings but serve as authoritative materials for road management, if you do not confirm certain points before CAD conversion or CAD editing, issues such as positional shifts, scale discrepancies, layer confusion, insufficient attributes, and missed updates are likely to occur.

In practice, common issues include existing drawings being old, a mix of data consisting only of scanned paper drawings, unclear coordinate information, drawings that do not match actual conditions, and different management methods by department. Before handling road ledger attached maps in CAD, rather than immediately starting drafting or revisions, it is important to confirm the whole workflow: the purpose of the drawings, original source materials, coordinates, scale, layers, on-site verification, update rules, and operational procedures.

In this article, we organize eight items that practitioners should review before handling road ledger attached maps in CAD, presenting them from a perspective that is practical for road management in the field.

Table of Contents

• Clarify the purpose of handling road ledger attachment maps in CAD

• Confirm the condition of the original drawings and the source documents

• Confirm the scale, map frame, and display extent

• Confirm the coordinate system and alignment conditions

• Organize the layer structure and line-type rules

• Confirm how to handle road widths and boundary information

• Check for inconsistencies with current conditions

• Decide the operational rules for updating and sharing

• Summary

Clarify the purpose of handling road ledger attached maps in CAD

Before working with the maps attached to the road ledger in CAD, the first thing to confirm is the purpose: why you are converting them to CAD. There is not just one reason to handle road ledger maps in CAD. Depending on the purpose, such as making paper drawings easier to store, making it easier to check road widths and boundaries, using them as materials for occupancy consultations or road construction, streamlining updates to the road ledger, or overlaying them with other map data or survey results, the required accuracy and scope of work will differ.

For example, if the purpose is to improve readability, simply scanning existing paper drawings and placing them on CAD within the necessary area so they can be referenced can still be effective to some extent. However, if you are editing road areas or boundary lines as management records, merely placing images is insufficient. You need to organize line segments, text, dimensions, symbols, and attributes so the data will be understandable to anyone who looks at it later. Furthermore, when comparing with on-site survey results or as-built road construction drawings, managing coordinate consistency and positional accuracy becomes important.

If CAD work is started without a clear purpose, the decision criteria will shift during the process. Decisions such as how far to trace lines, whether to correct discrepancies in existing drawings, how to treat parts that differ from current conditions, and how much annotation to enter on the drawings will vary from person to person. As a result, although the appearance may be neat, the data can lack the reliability required of maps attached to the road register.

When clarifying the purpose for handling CAD, it is important to distinguish whether it is for viewing, editing, updating, or for linking with a management ledger. If it is for viewing, readability and searchability are prioritized. If it is for editing, standardization of layers and line types is important. If it is for updating, linking change histories and supporting documentation is indispensable. When linking with a management ledger, a major point is how to map shapes to attribute information.

Also, the work of handling road ledger attached maps in CAD is not something that ends once it is created. Roads continuously change due to widening, improvements, pavement repairs, occupancy works, zoning changes, boundary confirmations, and so on. Therefore, it is necessary to design not only for the initial CAD conversion but also with future update work in mind. If you prioritize only short-term work efficiency, you may create a data structure that is difficult to modify later, which can result in increased effort for maintenance and updates.

Before working with maps attached to the road ledger in CAD, it is also important to confirm with relevant departments and contractors what the final deliverable should be. Work planning will vary depending on whether only CAD data will be delivered, whether review PDFs will also be produced, whether management will be organized by drawing number or by route name, or whether the data will be linked to the road ledger’s records and related materials. Deciding the purpose in advance reduces unnecessary work and makes it easier to ensure the required level of accuracy and information.

Confirm the condition of the original drawings and primary source materials

Before handling road ledger attached drawings in CAD, you must always check the condition of the original drawings. Road ledger attached drawings involve various source materials, such as paper drawings, scanned images, PDFs, previously created CAD data, as-built drawings, survey results, and boundary confirmation documents. If you proceed without deciding which material should be treated as authoritative, information from multiple materials can become mixed, and you may later be unable to determine which lines are correct.

When working from paper drawings, first check the condition of the drawing itself. Creases, tears, stretching, smudging, fading, handwritten notes, or distortion from copying can cause misalignment or reading errors when converted to CAD. In particular, on older road ledger maps, parts of the drawing may be missing or the text may be difficult to read. If you simply trace drawings in this state, you may end up digitizing incorrect lines or annotations.

Care is also needed when working from scanned images or PDFs. Just because something appears as an image does not mean it has the correct scale or position. Tilt or skew during scanning, insufficient resolution, per-page scaling differences, differing margins, and line degradation due to image compression can make it difficult to handle accurately in CAD. When importing scan data into CAD, you need to verify whether you can correct the image’s skew and scale using drawing border lines, reference points, known distances, road centerlines, and so on.

Even if CAD data already exists, that data is not necessarily up-to-date or correct. There can be issues such as only parts having been modified in past work, layer names differing between persons in charge, unnecessary lines remaining, coordinates left in provisional positions, or external references and garbled text occurring. While CAD data is easy to edit, information that has been changed by mistake can be difficult to notice from appearance alone. Therefore, when using past data it is important to verify the creation date, update date, creator, justification for updates, and the relationship to the original source materials.

When examining original source materials, you should check not only the road ledger attached maps but also related road ledger records, area determination documents, boundary confirmation documents, land acquisition maps, survey results, as-built drawings, and occupation-related materials. The road ledger attached map shows the shape of the road as a drawing, but behind it there are documents that serve as the administrative basis. Even if boundary lines are drawn on the drawing, how they are treated varies depending on whether their basis is found in boundary confirmation documents or is an estimate from past ledger maintenance.

Before handling documents in CAD, organize the level of confidence for each source document to make practical work proceed more smoothly. By clarifying whether to prioritize the latest survey results, official road-area documents, or historical ledger-attached maps, it becomes easier to make judgments when discrepancies arise between sources. Because road ledger attached maps involve many stakeholders, it is important not to make corrections based solely on the judgment of the person in charge, but to update them while clearly indicating the supporting evidence.

Carefully checking the condition of the original drawings and the source materials can greatly reduce rework after CAD conversion. In particular, if errors are discovered later in the maps attached to the road ledger, this can lead not only to revisions of the drawings but also to reviews of the ledger information and related documents. Organizing the materials' source, recency, accuracy, and any omissions at the initial stage provides the foundation for creating reliable CAD data.

Confirm the Scale, Map Sheet Boundary, and Display Extent

When handling maps attached to the road ledger in CAD, confirming the scale, map frame, and display extent is extremely important. Maps attached to the road ledger are often created at a fixed scale, and elements such as road width, boundaries, topographic features, and annotations are represented based on that scale. Because CAD allows arbitrary zooming, scale errors can be hard to notice from appearance alone. If you do not confirm the scale reference before starting work, distance and area measurement results may be inaccurate.

When scanning paper drawings and importing them into CAD, the display magnification of the scanned image and the actual drawing scale are different. Even if a road width looks plausible on the screen, it does not necessarily match the real-world distance. You need to verify that lengths in CAD correspond to actual dimensions by using road widths and known dimensions, drawing sheet/frame dimensions, coordinate grids, distances between reference features, and so on. Even a slight scale error can lead to large positional discrepancies over long routes.

Checking the map sheet boundaries is also essential. Road ledger maps are often divided and managed by map sheet, and at the connection between adjacent sheets the road centerlines or boundary lines can be misaligned. When working in CAD, you need to check the connections with adjacent map sheets as well as tidy up a single drawing. If lines are broken, duplicated, angles altered, or annotations inconsistent at the junctions, the material becomes difficult to use as road management documentation.

You also need to define the display extent before starting work. The attached maps in the road register may depict not only the road area but also surrounding land parcels, buildings, rivers, drainage channels, slopes, road appurtenances, and encroachments. Whether you limit the CAD conversion to the road area, include surrounding features, or capture all annotations and dimensions will change the workload and the nature of the deliverable. If you proceed without deciding the display extent required for the purpose, you may end up entering unnecessary details or, conversely, omitting information that is needed.

When checking scale and map frame, attention must also be paid to the time when the original drawing was produced. Older maps attached to road ledgers may use representations that differ from current standards or from the present conditions. Also, if paper drawings were copied and used in the past, the magnification in the vertical and horizontal directions may have subtly changed during the copying process. When scale discrepancies differ between the vertical and horizontal directions, simple uniform scaling cannot fully correct them. In such cases, it is important to use multiple control points and known distances to verify the extent of the distortion.

When handling road ledger attached drawings in CAD, you also need to take the printing scale into account. Even if you are working at full scale on the screen, the scale can change at output depending on paper size and margin settings. When outputting road ledger attached drawings as materials for viewing or consultation, you must confirm that the scale indication on the drawing, the scale bar, the drawing frame information, and the paper size are consistent. If the drawings will be used in printed form, not only the accuracy of the CAD data but also the readability of the output is important.

Checking the scale, map sheet, and display extent beforehand stabilizes the standards for CAD work. Road ledger maps are not documents where simply drawing lines is sufficient. When it is clear which area is being managed, at what scale, and in which map-sheet units, subsequent editing, review, sharing, and updating proceed smoothly.

Confirm the coordinate system and alignment conditions

Before handling the maps attached to the road ledger in CAD, it is very important to check the coordinate system and alignment conditions. In CAD, you can draw shapes at arbitrary positions or place them according to actual coordinates. If you only need to adjust appearance, you can work with provisional coordinates, but when overlaying survey results, map data, current measurement data, road facility information, and so on, placement based on the correct coordinate system is required.

Which coordinate system a road ledger attached map was created in can be confirmed from notes within the drawing, map frame information, control points, survey results, and past maintenance specifications. If you overlay it with other data while the coordinate system is unknown, positions may be significantly offset. In particular, due to regional coordinate conditions, differences in geodetic datums, and differences in the drawing creation date, data that should indicate the same location may not align. When handling road ledger attached maps in CAD, it is necessary to clarify which coordinate system is being used as the reference.

When placing paper drawings or image data into CAD, you need to decide on an alignment method. Typical methods use known points on the drawing, road intersections, boundary points, control points, or points with public coordinates to align them. However, older drawings may have distortions in the drawing itself, so aligning based on only a single reference point does not necessarily ensure correct overall correspondence. It is important to check multiple points and determine over which area and to what extent the offsets occur.

In alignment, there are cases where simple translation, rotation, and scale correction are sufficient, and cases where correction of drawing distortion becomes necessary. When simple corrections can handle the task, recording the procedure makes it easier to ensure reproducibility. On the other hand, if the displacement differs by location, the original drawing itself may have limits in accuracy. In that case, forcing a full match will cause inconsistencies elsewhere. You need to decide in advance what to use as the reference and how much error to tolerate.

On maps attached to the road register, lines with different positional meanings—road centerlines, road boundary lines, public–private boundaries, parcel boundaries, road facilities, and so on—are drawn on the same sheet. Not all lines are necessarily created with the same level of accuracy. Even if the road boundary line is important for management, background buildings and topographic lines may be only reference information. When overlaying in CAD, it is necessary to distinguish which lines should be treated as authoritative and which should be treated as references.

If you proceed with CAD conversion without confirming the coordinate system and alignment, it will cause major rework later when integrating with field survey data and map information. In particular, when maps attached to the road ledger are used as shared data within a municipality, the same data may be referenced by multiple workflows such as road management, occupancy management, construction management, disaster prevention, and maintenance and repairs. If the positional reference is ambiguous in such cases, different decisions are likely to be made by each department.

Before working with CAD, it is important to record the coordinate system, reference points, alignment methods, corrections applied, remaining errors, and the sources referenced. By documenting not only the appearance of the drawing but also the rationale for placing features in those positions, you can enhance the reliability of maps attached to the road register.

Organize layer structure and line-type rules

When handling road ledger attached maps in CAD, organizing the layer structure and linetype rules is an important factor that affects work efficiency and data quality. CAD data can present a large amount of information on a single screen, but if layers and linetypes are not organized, editing and verification become difficult and mistakes during updates increase. Because road ledger attached maps contain diverse information, it is essential to decide on classification rules from the outset.

The information handled in maps attached to the road ledger includes road area lines, road centerlines, width lines, boundary lines, road facilities, sidewalks, side gutters, bridges, retaining walls, slopes, encroachments, terrain, text, dimensions, map frames, legends, etc. If these are combined into the same layer, it becomes cumbersome when you want to display only specific information or make edits. Conversely, if you divide them too finely, the number of layers grows too large and becomes difficult to manage. It is important to classify with a level of granularity that is practical for day-to-day use.

Layer names need to be understandable even if the person in charge changes. Using abbreviations or names that resemble personal work notes prevents later viewers from determining the content. In drawings attached to the road ledger, it is important to assign layer names in accordance with their operational meaning. For example, structuring them so that their role on the drawing is clear—lines related to road areas, lines related to boundaries, lines related to road facilities, and information related to annotations—makes checking and updating easier.

Rules for line types and line widths also need to be established. Important lines, such as road area lines and boundary lines, should be depicted so they can be distinguished from other reference lines. If everything is drawn with the same line type and width, the drawing may be visible, but it will be difficult to determine which lines are important for management. While CAD can distinguish them by color and line type, you should also confirm whether they remain distinguishable when printed or exported to PDF.

Handling text information is also important. Maps attached to the road ledger contain many pieces of text, such as route names, widths, lengths, lot numbers, facility names, notes, and update information. If text remains as images when converting to CAD, it cannot be searched or edited. On the other hand, re-entering all text is laborious. You need to decide, based on your purpose, which text information should be treated as editable data and which should remain as part of the background image.

When handling existing CAD data, pay attention to unnecessary lines and duplicated geometry. If past revision lines, temporary construction lines, lines duplicated for printing, overlapping text, or unorganized blocks remain, they can interfere with measurement and editing. Even if something looks like a single line, it may actually consist of multiple overlapping lines. Using such data as-is can lead to accidentally leaving unwanted information or deleting necessary information during later revisions.

Layer structure and line-type rules should be decided on the premise that they will continue to be used not only during initial setup but also for future updates. Road ledger attached drawings are materials that are managed over the long term. To ensure updates can be made under the same rules even if the person in charge changes, it is reassuring to leave simple operational rules such as a list of layers, the meanings of line types, text sizes, how things appear when output, and the handling of non-editable layers.

By organizing layers and linetypes before handling road ledger drawings in CAD, you can improve not only the readability of the drawings but also their reusability as data. In road management practice, being able to instantly display necessary information, hide unnecessary information, and reliably identify areas requiring correction leads to significant efficiency gains.

Confirm the handling of road widths and boundary information

When handling road ledger maps in CAD, road widths and boundary information are items that should be checked particularly carefully.

Road width is referenced in many situations, such as road management, occupancy consultations, road construction, building permit review, and maintenance and repairs. Boundary information concerns road areas and public–private boundaries, so incorrect handling can lead to misunderstandings with stakeholders and rework of verification tasks.

When handling road widths in CAD, it is necessary to verify whether the width indicated on the drawing matches the width actually measured from the geometry. In older maps attached to road ledgers, the width recorded in annotations may not completely match the road width shown in the geometry. This can be influenced by the scale used when the drawing was created, surveying accuracy, distortion of the paper drawing, and later road improvements. When redrawing lines in CAD, it is necessary to clarify whether to prioritize the annotations, the geometry, or the results of field surveys.

There are multiple concepts of road width, such as overall width, roadway width, sidewalk width, shoulder, width including side ditches, and width as the road area. Widths that look the same on drawings can have different meanings for management purposes. When converting to CAD, you should not simply represent the road with a line from edge to edge; you need to interpret which width is being indicated. When handling width lines and dimension annotations, it is important to also confirm consistency with the record information in the road ledger.

Care should be taken with boundary information because road-area lines, public–private boundary lines, parcel boundaries, and management boundaries can easily be confused. The lines shown on road ledger maps do not necessarily indicate finalized boundaries. Lines drawn as references during past ledger maintenance, lines based on map information, lines based on survey results, and lines whose boundaries have been verified differ in their levels of reliability. If the same line type is used in CAD, users will not be able to distinguish those differences.

When handling boundary information in CAD, linking it to source documents is also important. By recording which documents—such as boundary confirmation statements, land acquisition documents, survey maps, as-built drawings, and boundary change documents—you based the lines on, you make it easier to respond when verification is needed later. While road ledger maps are easily referenced in daily work, caution is required when making judgments about boundaries. Therefore, it is important not to draw conclusions solely from lines in CAD, but to ensure that you can return to the source documents as needed.

Also, roadway widths and boundary information may not match the current conditions. The area being used as a road on site may differ from the road area recorded in official registers. There are cases that are difficult to judge from drawings alone, such as past widening works not being reflected, changes in the positions of side ditches or retaining walls, or private structures located close to the road area. Before handling data in CAD, it is desirable to carry out on-site verification and cross-checks with survey results as necessary, and to manage drawing information and current-condition information separately.

Road width and boundary information are among the most frequently used—and most consequential when incorrect—data in maps attached to the road ledger. Precisely because CAD conversion makes them easier to view and edit, it is necessary to clarify the meaning of the lines, the basis for them, their accuracy, and their update history. It is important not only to produce neat-looking drawings but also to make the data explainable as road management documentation.

Check for inconsistencies with the current situation

Before handling road ledger attached drawings in CAD, it is essential to verify any inconsistencies with the current conditions. Road ledger attached drawings are documents created in the past, and after their creation road improvements, pavement repairs, sidewalk construction, side-ditch rehabilitation, retaining wall installations, intersection improvements, occupancy works, and roadside development may have been carried out. Because the information on the drawings does not necessarily match the present road conditions, it is necessary to decide in advance how extensively to verify the current conditions before digitizing them in CAD.

A common mismatch with actual conditions is differences in road width. Even if drawings depict a uniform width, some sections in the field may have been widened, or the positions of shoulders and side ditches may have changed. Also, at intersections and on curves, the alignment shown in the drawings can be offset from the actual conditions. Even if you neatly trace old drawings in CAD, if they do not match the actual conditions, the data becomes difficult to use in practical road management.

Discrepancies in road facilities are also significant. Side ditches, catch basins, signs, lighting, guardrails, bridges, retaining walls, slopes, and transverse structures may change their location or form as a result of replacement or renovation. If outdated facilities remain on the maps attached to the road ledger, they can cause misunderstandings during maintenance and construction planning. Even if it is difficult to inspect every facility in detail, it is important to prioritize verifying facilities that are critical for road management or that are frequently updated.

Information on occupied fixtures and underground buried objects is another area where discrepancies with current conditions easily arise. Road occupancy is managed based on applications and permits, but updates to drawings may be delayed. If old information is imported as-is during CAD conversion, it can cause confusion when confirming current conditions. How much occupancy information to display on the maps attached to the road ledger varies depending on the practices of each municipality or manager, but if it is displayed, the timing of information updates and the basis for them need to be clearly indicated.

Methods for confirming existing conditions vary depending on the purpose and required accuracy. For a simple check, you can refer to site photos, field notes, existing inspection records, construction documents, and the like. If more accurate verification is needed, perform high-precision positioning and surveying on site and reconcile the results with CAD data. When preparing the maps attached to the road ledger as update data, it is important to record the differences from the current conditions and to clearly identify which parts are to be updated.

If the current conditions differ from the road ledger map, it is not always appropriate to immediately revise the drawings. Because the road ledger map has administrative significance, you need to confirm whether the change would involve an official modification of the road area or of the ledger information before moving lines to match the current conditions. Even if the current conditions have changed, the ledger’s area changes may not yet be completed. In such cases, it is effective to distinguish between current-condition information and ledger information and manage them with notes or on separate layers.

Identifying inconsistencies with current conditions before converting to CAD can reduce correction instructions after the work and misunderstandings among stakeholders. Road register maps are used in a wide range of situations such as site work, design, management, occupancy, and responses to residents. Grasping the parts that do not match the current conditions and clarifying how far to reflect them is an important preparation for producing CAD data that can be used in practice.

Establish operational rules for updates and sharing

Before handling road ledger attached maps in CAD, it is important to define operational rules for updating and sharing. Because CAD-converted road ledger attached maps are easy to edit, it is convenient when multiple personnel are involved, but there is also a risk that it becomes unclear who changed what and when. To preserve their reliability as road management documents, you need to organize in advance the update procedures, approval workflow, storage locations, file naming, version control, and sharing methods.

The first thing to decide in an update rule is when to update the attached maps of the road ledger. There are multiple triggers for updates, such as upon completion of road works, when area boundaries change, after boundary confirmation, when occupancy information changes, after periodic inspections, and after current-condition surveys. If the timing for updates is unclear, it becomes easy for a situation to arise where construction documents contain new information but the attached maps of the road ledger do not reflect it. By clearly specifying the operational events that should trigger updates, you can more easily prevent omissions.

Next, it is necessary to establish a procedure to always retain the supporting documentation for updates. Simply modifying a line in CAD does not allow you to later verify why it was changed to that position. It is important to organize the materials that form the basis for the revisions—such as as-built drawings, survey results, boundary verification documents, site inspection records, and approval documents—and manage them so they correspond to the CAD data. In particular, for revisions involving road areas or boundaries, the presence or absence of supporting evidence is critical.

Version control is also indispensable. When multiple people handle the maps attached to the road ledger, old and new files can coexist. If you manage them only by file name, it can become unclear which is the latest version. You need to manage the update date, affected route, map frame number, version number, update details, and so on according to a set of rules so that the latest version and past versions can be distinguished. Keeping past versions makes it easier to compare before-and-after changes and to restore data in case of erroneous updates.

Regarding sharing methods, simply distributing files is not sufficient. Because CAD data is editable, it is desirable to separate viewing and editing versions. If stakeholders only need to confirm the content, it may be safer to share it in a non-editable format. On the other hand, those responsible for updates need to be provided with editable CAD data together with related materials. It is important to assign viewing, review, editing, and approval permissions according to users' roles.

Keeping a record of updates is also important in everyday operations. When you revise the maps attached to the road ledger, record which route and which section was changed, on the basis of which documents, and exactly how it was changed, so that it is easier to explain when inquiries arise later. This is especially important for municipalities and road managers, where staff transfers or changes in contractors may occur. If the update history is not retained, the next person in charge will be unable to trace past decisions and will end up repeating the same verification tasks.

To use CAD data over the long term, attention must be paid to file formats and data compatibility. If data are made accessible only in a specific environment, it could cause problems for future operations. Because road ledger attached maps are materials used over a long period, it is reassuring to manage editing data, viewing data, and archival data separately and to ensure they can be converted or checked as needed.

Operational rules for updating and sharing should not be established after CAD work is finished. Deciding them before starting CAD conversion stabilizes the way deliverables are produced. Treating the road ledger's attached drawings not merely as drawing data but as management information that is continuously updated contributes to long-term operational efficiency.

Summary

Using CAD to handle the maps attached to road ledgers greatly helps improve the efficiency of road management operations. It makes it possible to organize road areas, widths, boundaries, and facility information that were difficult to verify from paper drawings or PDFs alone, and to edit while displaying the necessary information, which facilitates updates and sharing with stakeholders. However, CAD conversion is not simply tracing drawings. Because the maps attached to road ledgers are used as source documents for management, insufficient checks before starting work can lead to data that looks tidy but is difficult to use in practice.

First, it is important to clarify the purpose for which the CAD will be used. Whether it is for viewing, editing, updating, or linking with other management information will affect the required level of accuracy and the scope of work. Once the purpose is decided, it becomes easier to make consistent decisions on checking original drawings and source materials, organizing scale and drawing frames, confirming coordinate systems and alignment, designing layer structures, handling road widths and boundary information, reconciling with current conditions, and the operational rules for updating and sharing.

What deserves particular attention is that the information in the maps attached to the road ledger has both provenance and currency. Just because a line is drawn on a plan does not mean that the line necessarily represents the current on-site conditions or an official boundary. It is necessary to cross-check old drawings, scanned images, past CAD data, survey results, as-built drawings, boundary confirmation documents, and so on, and to clearly determine which information should be treated as authoritative. Precisely because editing in CAD makes changes easier, it is important to avoid unfounded edits and to maintain the data so that it can be explained.

Also, the post-CAD operation needs to be considered from the very beginning. Road ledger maps are not documents that are finished once prepared; they are continuously updated in response to road works, boundary changes, field inspections, maintenance and repairs, occupancy management, and the like. By establishing rules for layers and line types, file management, version control, update history, and separation of viewing and editing, you can ensure road ledger maps remain usable even when personnel change.

Before handling road ledger attached drawings in CAD, it is important to be aware not only of the drawings' appearance but also of their consistency with the actual site. Road widths, boundaries, side ditches, structures, and road appurtenances may reveal differences only through on-site verification. Rather than judging solely from paper or on-screen drawings, obtain high-precision positional information on site as needed and compare it with the CAD data to develop road ledger attached drawings that are better suited for practical work.

If you want to improve the accuracy of field verification and updates to road ledger attached maps, using smartphone-mounted, high-precision GNSS positioning devices such as LRTK makes it easier to apply position information collected on site to the verification of road ledger attached maps and CAD data. By combining the work of handling road ledger attached maps in CAD with high-precision on-site position verification, you can achieve not only better drawing management but also overall efficiency and quality improvements in road management.