6 Conditions to Check Before Conducting Slope Surveying with an Electro-Optical Distance Meter

Slope surveying is an important task at sites such as roads, land development, rivers, erosion control, residential land, and disaster recovery, for understanding the shape, height, gradient, and construction extent of slopes. Because a total station can determine positions from distances and angles, it is used to measure items such as the slope crest, slope toe, small benches, change points, and interfaces with structures. On the other hand, unlike flat ground, slopes are places that are more susceptible to issues with line of sight, safety measures, footing, reflector placement, choice of survey points, and weather. If insufficient conditions are discovered after starting surveying, it can lead to re-surveys and rework, and may affect construction management and as-built verification.

This article organizes six conditions that field practitioners should check before conducting slope surveying with a total station.

Table of Contents

• Organize the prerequisites for using a total station in slope surveying

• Condition 1: Confirm the positional relationship between the reference point and the backsight.

• Condition 2 Secure an observation position from which the entire slope can be seen

• Condition 3: Decide survey points such as slope shoulder, slope toe, and small benches in advance

• Condition 4: Confirm the area where it is safe to enter and the work circulation routes

• Condition 5: Check weather, ground surface conditions, and reflection conditions

• Condition 6: Align recording methods and verification procedures

• Approach to Reducing Rework in Slope Surveying Using a Total Station

• Summary

Clarifying the prerequisites for using a total station in slope surveying

When conducting slope surveys with an optical total station, the first thing to clarify is the purpose of the measurements. Even when referring simply to slopes, the required survey points and accuracy considerations vary depending on the objective: understanding the existing topography, pre-construction baseline surveys, as-built verification after excavation, checking embankment geometry, monitoring displacement at collapse locations, and verifying interfaces with structures. If observations begin without a clear objective, you may only record the easily measured points and later find that necessary change points are lacking.

A total station is an instrument that sights a target point from an instrument station and determines coordinates and elevations based on horizontal angle, vertical angle, and slope distance. In slope surveying, you cannot always choose instrument stations or prism positions freely as you can on flat ground. Because visibility is restricted by the slope’s undulations, vegetation, soil and debris, structures, temporary installations, and the placement of heavy equipment, pre-survey planning affects the stability of the results.

Moreover, slope geometry changes continuously. In some cases measuring only the slope crest and toe is sufficient, while in others it is necessary to capture in detail intermediate break points, small benches, spring zones, overhangs, scoured areas, collapse scars, and so on. For as-built verification, comparison with the design cross-section becomes important, whereas for understanding the current conditions the point density that can adequately represent changes in the terrain is important. In other words, before setting up a total station on site, it is essential to decide what you intend to present as the deliverable.

In slope surveying, not only coordinates but also vertical consistency is important. Even if the horizontal positions agree, a shift in the vertical datum will affect slopes, earthwork quantities, and as‑built evaluations. Procedures for transferring elevations from known points, verifying benchmarks, handling temporary leveling points, and the coordinate system and rules for local coordinates used on site need to be shared in advance. When surveying over multiple days or with multiple teams, you should also confirm that the setup on the first day matches that used on subsequent days.

Furthermore, on slope sites, safety management cannot be separated from surveying plans. Even if there are points you want to measure, if entering those locations poses a risk of falling or rockfall, you need to consider alternative observation methods or different ways of establishing survey points. Total stations are well suited for confirming positions point by point, but when workers move while carrying a reflector, careful coordination is indispensable—covering workers' positioning, signaling, and their relationship with nearby heavy machinery. The fundamentals of slope surveying are not to consider only measurement accuracy, but to obtain the necessary results safely and in a reproducible manner.

Condition 1 Confirm the positional relationship between the reference point and the backsight

Before carrying out slope surveying with a total station, the first condition to check is the positional relationship between the reference point and the backsight. In slope surveys, attention tends to be drawn to the slope itself, but the foundation of the observations is the relationship among the instrument station, the backsight, and known points. If you begin surveying while this relationship is unstable, no matter how carefully you measure points on the slope, errors can occur in the overall position and orientation.

The instrument point is the position where the optical surveying instrument is set up. The backsight point is the point sighted to establish direction. If the coordinates, elevations, point names of known points and control points, and the coordinate system to be used are not clearly defined, the observation results cannot be properly organized. Especially in slope surveys, since measurements are often checked by overlaying construction drawings, design cross-sections, and existing plan views, it is important to confirm in advance where the coordinate reference used on site is located.

When the distance to the rear sight point is extremely short, a slight directional deviation can appear large at distant survey points. On sites where the slope’s length and width are large, you may need to measure the slope shoulder or slope toe that are far from the instrument point, so stability in the rear-sighting direction is especially important. Choose a rear sight point that can be sighted as clearly as possible, is unlikely to move, and is easy to recheck. Even when using temporary stakes or simple markers, you must confirm they are secured so they will not shift or fall over during operations.

Also verify the height reference at the same time. In slope surveying, many decisions relate to elevation, such as gradients, steps, cut volumes, fill volumes, and drainage slopes. Errors in the instrument height, the height of the prism or reflector, the elevations of known points, or the handling of temporary benchmarks will affect the entire set of observations. Common field mistakes include entering the wrong prism height and failing to record changes when the pole height is altered during work. Decide on a method to verify height inputs before starting work and develop the habit of rechecking at key points during observations.

Keep reference points and backsight points in a condition that allows them to be rechecked during work. In slope surveying, you may need to move instrument stations to continue observations. In such cases, it is reassuring to leave points that can be measured from both the previous and the new instrument stations so you can confirm that the observations are consistent. If you must use multiple instrument stations because of line-of-sight constraints, plan the relationships among the stations in advance so the survey network remains continuous.

Also, attention must be paid to the surroundings of control points. Control points near slopes can be affected by heavy equipment traffic, movement of temporary materials, inflow of rainwater, ground loosening, and similar factors. Even if stakes or pins are visible, if there is a possibility they have actually moved, check against another known point or re‑survey to confirm there are no anomalies. Proceeding with surveying when control points are unreliable makes it difficult to determine the cause later.

When using a total station, each aspect of the setup — installation accuracy, leveling, centering, and backsight verification — affects the results. Slopes often have large elevation differences between survey points and viewing angles that change easily, so errors are likely if the instrument is poorly set up. Set the tripod on stable ground and check that the legs do not sink and that the setup will not be disturbed by passing traffic or vibration. When placing the instrument near the slope shoulder or on an embankment, the ground may be loose, so it is advisable to re-check the leveling and centering after installation.

Condition 2 Secure observation positions that provide a clear view of the entire slope surface

Next, the condition to check is from which positions the entire slope can be viewed. A total station assumes that the points to be measured can be sighted. The slope extends vertically and horizontally, and if vegetation, berms, temporary protective fences, sandbags, drainage facilities, heavy machinery, or other obstructions are present, the required points may become obscured. Before deciding observation positions, visually survey the slope crest, slope toe, center of the slope, berms, edges, and where it meets structures to confirm which points will be visible and which will be hidden.

Observing the slope from a position close to its face makes it easier to grasp its shape, but you cannot always set up the equipment there. There are constraints on locations that can be used as instrument stations, such as on the roadway, in a temporary yard, on the riverbed, on adjacent land, or on a work passage. The observation position is decided by considering, in combination, that it can be set up safely, that the tripod will be stable, that the backsight is visible, that it will not interfere with operations, and that it will be easy to guide people to the survey points.

When observing a slope obliquely, the shape in the depth direction can become difficult to discern. Even if you think you have picked up the positions of the slope shoulder or slope toe, the visible edge may actually be offset from the line you want to confirm in the design. This is especially true at the slope edges and curves, where the apparent contour may not coincide with the line that should be measured. Check the construction drawings and on-site markings, and ensure workers share which line each measurement point lies on.

If the entire area cannot be observed from a single instrument station, plan to use multiple observation positions. In doing so, you should not merely move the instrument to an unseen location; you must establish common points to link the observations taken before and after. Measuring several common points makes it easier to verify consistency after moving the instrument station. Select points that are easy to re-aim at—such as the left and right edges of the slope, near the slope shoulder, and around stable structures—to keep operations steady.

Pay attention to the sighting angle when deciding the observation position. When observing at an extremely steep angle—either looking up or looking down—the orientation of the reflector and the ease of sighting can affect the results. If you look up at the upper part of a slope from below, the backside of the slope shoulder and the upper edge can become difficult to see. Conversely, when measuring downward from above, take care with footing safety and the risk of falling objects. It is not a question of which is correct; what matters is choosing a position from which the point to be measured can be reliably sighted and where workers can move safely.

Also, the surface condition of a slope affects visibility. If grass is overgrown, the boundaries between the slope shoulder and slope toe can be hard to see. If there are loose rocks or collapsed soil, the positions where workers can place reflectors are limited. When the surface appears uniform, such as with weed-control sheets or sprayed surfaces, it is also easy to overlook change points. Walk the site and check before surveying, and, if necessary, mark the survey point locations to reduce hesitation during observations.

Movements of heavy equipment and work vehicles also affect observation positions. In slope work, excavation, shaping, loading, slope protection, and drainage may all proceed within the same area. If the location where the total station is set up is close to the work routes, the risk of vibration or contact increases. Heavy equipment can also block the line of sight during observations. It is advisable to confirm the work schedule and coordinate on site so that the line of sight and safety can be secured, at least for the time required for surveying.

Condition 3 Predefine measurement points such as the slope crest, slope toe, and small benches

In slope surveying, it is important to decide in advance which points will be measured. A total station is an instrument for measuring points, but if the selection of points is inadequate, the results will not accurately represent the slope’s shape. Before beginning observations, it is essential to organize the necessary survey points according to the objective—such as the slope crest, slope toe, benches, break points, edges of drainage facilities, contact points with structures, and locations where distress or deformation is observed.

The slope shoulder is an important line corresponding to the upper edge of a slope. In construction management, the design position of the slope shoulder is sometimes compared with the current or as-built position of the slope shoulder. When the slope shoulder is finished with a rounded edge, or when vegetation, soil, or temporary materials make the boundary unclear, it is necessary to unify on-site which position will be measured as the slope shoulder. If different personnel make different judgments, measurements of the same slope can produce different results.

The slope toe is equally important. The slope toe often adjoins drainage facilities, side ditches, flat areas, retaining walls, or road edges, and even slight positional differences can affect the as-built condition and drainage planning. When sediment has accumulated or the shape is provisional during construction, clarify whether to measure it as the existing condition or to check it against the design line. Water tends to gather near the slope toe, and there are often mud and subsidence, so it's also necessary to confirm whether workers can stand safely.

On slopes with benches, it may be necessary to check the bench’s upper and lower edges, width, and gradient. Because benches affect the overall stability, maintenance, and drainage of the slope, they should not be treated simply as flat areas partway up the slope; determine in advance which line(s) to measure. If materials or soil are placed on the bench, the actual shape may be concealed. Before surveying, check for any obstructions and ensure the necessary areas can be measured.

If there are break points or change points along a slope, you need to increase the point density when measuring. Even a slope that looks smooth can actually have subtle undulations caused by the movement of construction machinery and variations in ground stiffness. If the objective is simply to obtain a general understanding, representative points may be sufficient; however, when the data will be used for as-built verification or earthwork volume calculations, survey points should be arranged so that variations in each cross section can be represented. If there are too few survey points, the resulting drawings will appear simpler than the actual shape.

When deciding survey points, align the approach for the transverse and longitudinal directions. For slopes along roads or rivers, survey points may be placed along regular survey lines. On development sites or wide slopes, points may be collected in a grid pattern or centered on change points. In any case, it is important to decide on point names and recording methods so that, when organizing drawings and forms later, you can tell which points belong to which cross-sections. Even if you think you understood it at the site, it is not uncommon to find the meaning of points unclear after returning to the office.

When using reflectors, also confirm that the worker can correctly place them at the survey point. On slopes, it can be difficult to keep the pole vertical. On steep slopes, in mud, on crushed stone, in vegetation, or on sprayed surfaces, footing can become unstable and the reflector’s height and position may easily shift. If it is dangerous to stand at the survey point, rather than forcing a person to enter, decide to change how the survey point is taken, observe from a different angle, or set an alternative point within the accessible area.

Pre-setting survey points is also useful for aligning understanding with construction stakeholders. If the surveyor decides the survey points alone, they may not match the locations the construction manager wants to check. By sharing in advance what the survey results will be used for, which cross-sections or ranges are important, and how much detail is required, you can reduce the likelihood of re-surveying. In slope surveying, the planning of which points should be measured can have a greater impact on the quality of the deliverables than the act of measuring itself.

Condition 4: Confirm the areas that can be entered safely and the work flow paths

In slope surveying, confirming the areas that can be entered safely is indispensable. Observations with an optical surveying instrument require coordination among the person who sets up the instrument, the person who moves while carrying the reflector, and the person who records and provides guidance. Because slopes and their surroundings involve risks such as trips, slips, falling rocks, collapses, contact with heavy machinery, and flying or falling debris, it is necessary to check the planned work movement routes before surveying.

First, confirm whether it is necessary to enter the slope directly. When workers need to move to measurement points such as the slope shoulder, slope toe, or small benches, check whether the route to them is safe. Even if it looks passable, it can be dangerous if the surface is wet, vegetation hides your footing, or there are loose rocks. Slopes are especially likely to be unstable after rain or immediately after excavation. Prioritize judging whether you can approach safely before ensuring you can take exact measurements at the measurement points.

Care must also be taken when working near the slope shoulder. Even if the slope shoulder appears level, the soil at the edge may be loose. If equipment is set up close to the slope shoulder, tripod legs can sink and vibrations during operation may cause the edge to collapse. When observers are concentrating on sighting, they may pay less attention to their footing. It is important to keep a sufficient distance from the slope shoulder and to clearly mark no-entry zones and safe walkways.

Be cautious of falling rocks and the flow of soil near the toe of the slope. If work is being carried out above, it is dangerous for surveyors to be below. Even small stones or clumps of soil can lead to serious hazards when there is a difference in elevation. When working simultaneously on the upper and lower parts of the slope, do not rely solely on verbal calls or signals; adjust according to site rules by staggering work times, assigning observers, and avoiding entry into hazardous areas.

Interaction with heavy equipment is also important. During slope shaping and excavation work, heavy equipment may swing, reverse, or carry earth and soil. Survey personnel move while searching for points, so they may enter areas that are difficult for heavy equipment operators to see. Before starting surveying, confirm the heavy equipment’s operating range, standby positions, signaling methods, and evacuation points. If necessary, ensure safety across the entire site— for example, temporarily stopping heavy equipment operations while surveying.

Consider the work route not only for the outbound trip but also for the return. Even if you are careful when heading to a survey point on a slope, you may fall if you rush back after finishing measurements. When carrying a pole or recording equipment, your hands may not be free. In locations where movement takes time or that are hazardous, take measures such as reviewing the number of survey points, choosing different observation positions, or using multiple people to assist.

In slope surveying, means of communication are also important. When the distance between the instrument and the reflector increases, it becomes difficult for voices to carry. On sites with heavy machinery noise, wind, or river noise, signals can be hard to convey. To ensure clear transmission of instructions for survey points, signals that an observation is complete, changes in pole height, and evacuation instructions in dangerous situations, establish signaling methods in advance. Working with ambiguous signals can lead not only to mistakes in survey points and recording errors but also to safety problems.

It is important not to let safety checks be completed solely by the surveying personnel. Share them with the site representative, construction manager, heavy equipment operators, and workers, and make sure everyone knows when, where, and over what area the survey work will be carried out. Slopes are places where conditions can change easily. Areas that appeared safe in the morning may have their shape altered by afternoon as excavation progresses. You need to proceed with a mindset of checking for changes not only before surveying but also while work is in progress.

Condition 5: Check the weather, ground surface conditions, and reflection conditions

Before conducting slope surveying with a total station, check the weather, ground surface conditions, and reflector conditions. Slopes are outdoors and are affected by rain, wind, direct sunlight, fog, humidity, and temperature differences. Because a total station measures distance and angles, factors such as the ease of aiming, the condition of the reflector, and the stability of the instrument influence the survey results. Bad weather does not necessarily make measurement impossible, but poor conditions reduce work efficiency and safety and increase the amount of verification required.

When it is raining or just after rain, the slope surface becomes slippery. On earthen slopes there is mud; on crushed-stone or bedrock slopes there is slipping; and on grassy slopes poor visibility of the footing becomes a problem. If the worker standing at the survey point becomes unstable, it becomes difficult to hold the reflector in the correct position. If the pole tilts or the worker stands while searching for footing, the survey point can shift from the intended location. Even if the observed values look normal, the survey point position may actually contain errors.

Be cautious when winds are strong. If the wind is strong enough to sway the tripod, it will affect the stability of the instrument. Workers holding reflectors may also find it difficult to keep the pole vertical. Wind can be stronger at the top of a slope than on flat ground. Lightweight markers, drawings, or record sheets may be blown away, so assess whether the environment is appropriate for observations. Rather than forcing the work to proceed, choosing a time when the wind is weaker can often be more efficient.

Direct sunlight and backlighting also affect sighting. Depending on the sun's position, reflectors and survey points can become difficult to see. The slope surface may reflect brightly, making boundary lines hard to discern. If backlighting makes it difficult to judge the slope shoulder or slope toe, measures such as changing the observation position, adjusting the time of day, or placing markers at the survey points are necessary. Visibility cannot be overlooked, especially during as-built verification, because survey point positions judged by appearance are reflected in the results.

When there is fog or dust, visibility itself deteriorates. At sites where slope shaping is in progress or dry earth and sand are being handled, work can raise dust. In environments with a lot of dust, attention should be paid to protecting equipment and to contamination of lens surfaces. If lenses become dirty, sighting becomes difficult and survey efficiency declines. Before and after surveying, check the condition of your equipment, and rather than rubbing off dirt forcefully, maintain it in accordance with the equipment’s operating manual and the site’s management rules.

Also check the reflection conditions. When using a reflector, check the reflector's orientation, cleanliness, height, and how it is fixed. On slopes, it can be difficult to correctly orient the reflector toward the instrument. Especially when there is a large elevation difference, the instrument operator may not easily notice that the reflector's angle is off. Before observation, confirm with the worker handling the reflector how to align its orientation so it can be sighted steadily at each measurement point.

When measuring without a prism, attention must be paid to surface conditions. Soil, rock, concrete, vegetation, wet surfaces, and rough surfaces all reflect differently. There may be a mixture of points that are easy to measure and points that are difficult to measure, so you should proceed while checking that the distance displayed on the instrument is stable. If you measure the surfaces of grass or branches, you may pick up a position that differs from the actual ground surface. Be clear whether you want to measure the slope’s ground surface or structures and protective materials on the surface, and make sure you do not confuse the observation target.

Ground surface conditions are also important for interpreting changes in slopes. If there are features such as seepage, cracks, bulging, scour, signs of collapse, settlement, or steps/offsets, recording them separately from the regular survey points will be helpful for later verification. Survey results alone can make it difficult to convey why a point was measured. For distinctive locations, leaving their meaning in the point name or notes makes it easier to organize drawings and explain them in reports.

Condition 6 Standardize recording methods and verification procedures

In slope surveying, it is important to standardize recording methods and verification procedures so that observed data can be properly organized later. Points measured with a total station are saved in the instrument or in a recording device, but if the point name, the meaning of the measured point, the pole height, the conditions at the time of observation, and the relationship to the survey line are not clear, the results become difficult to use. Even if these details are understood immediately after measurement at the site, after time has passed they can no longer be reconstructed from memory alone.

Point names should be as systematic as possible. Use point names and notes so that the type of survey point—such as slope shoulder, slope toe, small terrace, change point, or structure edge—is identifiable. If naming rules differ by site, data organization becomes confusing. When multiple people are conducting observations, share the point-naming convention before work so that everyone uses the same approach regardless of who enters the data. Numeric-only point names can be organized, but they tend to lose the meaning of the points, so supplement them with notes or a field notebook as needed.

Managing pole height and reflector height is also important. On slopes, the pole height may be changed depending on the footing and sighting conditions. If you change it but do not correct the input on the instrument, height errors will be introduced. Before observations, confirm the current height aloud, and establish a procedure to always record any changes so that simple mistakes are easier to prevent. The more measurement points a site has, the more this basic check will affect the reliability of the results.

On-site checks after surveying are also indispensable. In slope surveying, if you notice missing points after returning to the office, you may need to go back to the site. If re-surveying is possible, that's still okay, but if construction has progressed and the shape has changed, you may not be able to measure under the same conditions. Therefore, once surveying is finished, check on site whether the planned points—slope crest, slope toe, small benches, edges, change points, etc.—have all been collected. Before leaving, it is important to perform a simple check for missing survey points, duplicated point names, or obviously incorrect coordinates or elevations.

When checking cross sections, also verify their correspondence with the survey lines. If it is unclear which point belongs to which cross section, you will be uncertain when drafting the drawings later. When organizing them as cross-section surveys, make sure to record survey line numbers, distance markers, left/right distinctions, and the correspondence between the slope shoulder and the slope toe. Even when organizing them as planimetric terrain, arrange survey points so important lines and boundaries can be traced, and preserve the meaning of the point sequences.

Useful verification procedures during observations include performing backsight checks and checks of known points partway through. During long observations, the instrument's mounting can change, the tripod can sink, or the equipment can be bumped during work. Especially around slopes, the ground may be unstable, so it's reassuring to verify the reference direction and known points not only at the start of observations but also during and at the end. If an anomaly is detected early, you can limit the extent of its impact.

Plan for backing up the data as well. Observational data collected on-site is not secure if left only on the device. Save it promptly after the work is completed, and organize it so that file names, dates, site names, and survey areas are clear. For multi-day operations, if you do not make clear which area was measured on which day, it becomes difficult later to check for overlaps or omissions. Because slope surveys are related to construction progress, recording the conditions at the time the data was acquired as well makes it easier to explain the results.

Standardizing recording methods is useful not only for quality control but also for explaining matters to stakeholders. When explaining the as-built shape and current condition of slopes, showing the meaning of survey points and the observation conditions increases confidence in the results. Conversely, even if many points have been measured, if you cannot explain what each point indicates, you may be asked to reconfirm. To turn the numbers obtained with a total station into information that can be used for on-site decisions, it is necessary to consider observation and recording as a single integrated process.

Approaches to Reducing Rework in Slope Surveying with a Total Station

When conducting slope surveys with a total station, reducing rework requires thinking of checks before, during, and after the survey as a continuous process. Before the survey, verify control points, observation locations, survey point plans, safety ranges, weather, and recording methods. During the survey, check line of sight, the condition of reflectors, point names, pole height, and any anomalies in observations. After the survey, check for missing survey points, consistency of coordinates and elevations, and whether you have all information necessary for drafting. When this workflow is in place, on-site decision-making becomes more stable.

Common causes of rework in slope surveying include failing to measure required points, becoming unclear about what the points represent, using different reference standards, parts being missing due to poor line of sight, errors in entering elevations, and being unable to re-survey after construction. These are not problems that can be solved by equipment performance alone. Rather, many of them can be prevented through pre-checks and information sharing on-site.

A total station’s strength is that it can aim at and measure the specific points you need. It can clearly capture points important for management, such as the slope crest and slope toe, edges of small benches, and interfaces with structures. On the other hand, no information remains for areas that were not measured as points. If you want to understand the overall shape of a slope in detail, you need to pay attention to point selection and point density. Decide—by working backward from how the results will be used—whether representative points are sufficient, whether to survey each cross section in detail, or whether to add points at locations of change.

Also, conditions for slope surveying change depending on the construction stage. Before, during, and after construction, the points that need to be measured at the same location differ. Before construction, the focus is on understanding the existing topography and obstructions; during construction, on checking the progress of excavation and embankment; and after construction, on verifying the as-built shape and finished condition. If it is not made clear which stage of the slope is being surveyed, the meaning of the results becomes ambiguous. It is advisable to include the survey date and construction stage in data names and records.

Verbal communication on site is also effective in preventing rework. Rather than allowing the surveyor to decide alone, confirming on the spot with the construction manager the lines and areas to be checked makes it easier to prevent omissions. Although the edges of slopes and junctions may be clear on the drawings, boundaries on site can be obscured by soil or temporary works. Any points that are unclear should be verified before surveying, and, if necessary, multiple points should be added to make later comparisons easier.

When conducting slope surveys with a total station, not only measurement accuracy but also the ability to respond to site conditions is required. If line of sight is poor, add instrument stations; if footing is hazardous, revise the survey point plan; if the weather is bad, adjust working hours; if a survey point’s meaning is unclear, supplement the records. By accumulating these judgments, the results become survey deliverables usable for construction management rather than mere point acquisition.

Summary

Before performing slope surveying with a total station, it is important to check six conditions: reference points and backsight points, observation positions, survey point plans, safety ranges, weather and ground conditions, and recording methods. Slopes impose greater constraints on line of sight and footing than flat terrain, and even identical surveying tasks can vary in difficulty depending on site conditions. Omitting these pre-checks can result in missed survey points, inconsistencies in position or elevation, re-surveys, and inadequate post-construction verification.

What's particularly important is to clarify the purpose of the measurements. Depending on whether it is documenting the existing conditions, a pre-construction survey, as-built verification, or deformation monitoring, the required survey points and the items that should be recorded will differ. A total station is an effective instrument for measuring targeted points, but if the selection of points to measure and on-site verification are insufficient, the results will be difficult to use. When observing, be aware of points that will be used for later decisions, such as slope shoulders, slope toes, small benches, break points, and junctions/interfaces.

Additionally, in slope surveying, ensuring safety must be the highest priority. Rather than forcing access to the point you want to measure, inspect work routes, the movement of heavy equipment, the risk of falling rocks or slipping, and changes in ground conditions due to weather, and choose a method that allows safe data collection. By integrating survey planning with safety management, you can reduce rework across the entire site and achieve more consistent results.

In the records, it is essential to retain the point name, pole height, the meaning of the measurement point, the construction stage, and the observation range. Data collected on site are organized in the office and used as drawings, forms, and construction management documents. In practice, it is important to make the results such that they are not understandable only to the person who took the measurements but can be followed and interpreted by other stakeholders as well.

In slope surveying, in addition to point-by-point observations using a total station, methods for efficiently capturing the entire site have come to be considered. In areas that are difficult for people to access, or when you want to preserve a shape as a surface, measurements using point clouds can be an effective option. If you want to grasp and record a wider area while covering key points with a total station, considering point cloud measurement methods alongside the total station according to site conditions and desired deliverables can make it easier to improve the accuracy and efficiency of slope management.