Page 3489
www.rsisinternational.org
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue X October 2025
Conditions and Limitations to be Considered while Using the Total
Station for Levelling Measurements
N. Malalarathne
1*
, M.A.R.D. Gunathilaka
2
, K.W.D. Sachinthana, D.R. Welikanna
3
1
National Aquatic Resources Research and Development Agency (NARA), Colombo 15, Sri Lanka
2
Survey Department of Sri Lanka
3
Faculty of Geomatics, Sabaragamuwa University of Sri Lanka
*Corresponding Author
DOI:
https://doi.org/10.51244/IJRSI.2025.1210000303
Received: 29 October 2025; Accepted: 05 November 2025; Published: 20 November 2025
ABSTRACT
Total station is a widely used instrument in the field of surveying for both distance and angle measurements.
Indirect levelling is a function that total station can be used but the level of accuracy that can be achieved is
uncertain. Therefore, it is expected to investigate conditions and limitations of using total station for leveling
through this study. An 8km long level line was established for this purpose, covering various topographical
features using into level. Selected segments of this level line were used for total station levelling. The result
achieved from total station was compared with auto level heights. Error variation of total station readings in each
segment was projected to graphs. According to results, the error was always negative when the level line slopes
downwards and positive when rises upwards. Error generation was higher as longer the distance between
instrument and target. Finally total station can be recommended for engineering surveys but not suitable for
water supply and drainage projects where accuracy is critical.
Keywords – Total station, surveying, levelling, error variation
INTRODUCTION
Background of the Study
At present, total station has been widely spread and used in many survey sites, and sometimes total station is not
fully used since users misunderstand the principles of this unit. One of them is the levelling, and in case use total
station for levelling, the method is classified as the indirect levelling method, and the method that will yield
acceptable misclosure and save time will be the best to be adopted for engineering works such as route surveying.
Levelling refers to height measurements for representing the relative difference in height between various points
on the earth. Common levelling instruments include the spirit level, the dumpy level, the digital level, auto level
and the laser level. In traditional method of levelling, where it is needed to be in touch on the ground. Therefore,
basic equipment such as tripod, auto level, staff, bubble staff, and measuring tape are used.
For engineering activities like road construction, often vertical position is obtained from a combination of
methods. Currently, level machine is used to establish vertical control. The method employs the use of auto level
instrument and graduated staffs. Accurate results are obtained when all of the systematic errors are controlled
and corrected. Short sight lengths and balanced sights are the most limiting restrictions. Generally, many
instrument stations have to be established in a level line when it passes in hilly and mountainous regions. This
increases the possibility of occurring instrumental errors and also extremely costly and time consuming.
Total Station is not exclusively used for levelling but it can be used for levelling under certain conditions and
limitations. This research is carried out to investigate such conditions and limitations and they may include,
topographic conditions, conditions in setting up instruments, weather conditions, distance between instrument
and target, target height etc.
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3490
www.rsisinternational.org
Problem Statement
When determining the height, number of instruments of different precisions and relatively different field
procedures which ends with different precisions are available. The highest precision in levelling is obtained by
the use of auto levelling. The use of total station levels saves computational and observation time. It is therefore
expected to be less tedious than the conventional auto levelling. The question is conditions and limitations to be
considered while using the total station for levelling measurements. It should be investigated whether it gives
the same precision compared to conventional analogue auto levelling. These are the problems which are going
to be discussed in the study.
Research Objectives
The objectives of the study are;
• Check the accuracy of total station for levelling and find whether misclosure is in acceptable range or not
• Find the suitability and usages of total station in water distribution and drainage
Scope and Limitations
The research would be helpful for users to select suitable instrument for a given task. The study is limited to an
8km long level line established using auto level and selected segments which cover a total distance of 5km for
total station levelling. The selected level line covered a relatively flat area, an undulated area and a slope area.
Conceptual Method
Level network was designed along the section in Pambahinna-Rajawaka road and established bench marks in
each kilometer. Study area was 8km in length. The study area was selected as it consist various topographies
from plain terrain to hilly major terrain. The area found to be favorable for easy walking and there was good
inter-visibility between consecutive points and also less traffic congestion existed.
Figure Error! No text of specified style in document..1 : Route for Level Network Establishment
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3491
www.rsisinternational.org
Figure Error! No text of specified style in document..2 : Conceptual Framework
LITERATURE REVIEW
Levelling is a branch of surveying which is used to find elevation with respect to a given or assumed datum and
to establish points with respect to a given or assumed datum. Therefore, levelling deals with measurements in
vertical plane.
Level Surfaces, Plumb Lines and Height Systems
A level surface is an equipotential surface which is always perpendicular to the direction of gravity in any point
on that surface. Plumb lines are imaginary lines which represent the direction of gravity. Plumb lines are defined
as truly vertical lines (COMET, 2015).
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3492
www.rsisinternational.org
Figure Error! No text of specified style in document..3 : Level Surface and Plumb Line (NOAA, 2016)
Height systems are defined in several ways as follows;
1. Ellipsoidal height: This is the distance along ellipsoid normal from ellipsoid to earth surface
2. Geoid height: This is the distance along ellipsoid normal between geoid and ellipsoid
3. Orthometric height: This is the height measured along the plumb line from geoid to earth surface
Figure Error! No text of specified style in document..4 : Height Systems (COMET, 2015)
Usages of Levelling
ï‚— For building construction
ï‚— For bridge and tunnel construction
ï‚— To design water distribution and drainage systems
ï‚— For volume calculation
ï‚— To get cross sections and longitudinal sections along roads, railways, canals etc
ï‚— To identify topography and drainage
Methods of Levelling
There are three principal methods for determining differences in elevation, namely, barometric levelling,
trigonometric levelling and spirit levelling (Tandon, 2013).
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3493
www.rsisinternational.org
Barometric levelling
Barometric levelling makes use of the phenomenon that difference in elevation between two points is
proportional to the difference in atmospheric pressures at those points. Therefore, a barometer may be used and
the readings observed at different points would yield a measure of the relative elevation of those points. At a
given point, the atmospheric pressure doesn’t remain constant in the course of the day, even in the course of an
hour. Therefore, this method is relatively inaccurate and is little used in surveying work except on reconnaissance
or exploratory survey (Tandon, 2013).
Trigonometric Levelling (Indirect Levelling)
Figure Error! No text of specified style in document..5 : Trigonometric Levelling (Punmia, 2015)
Trigonometric or indirect levelling is the process of levelling in which the elevations of points are computed
from the vertical angles and horizontal distances measured in the field, just as the length of any side in any
triangle can be computed from proper trigonometric relations. In a modified form called stadia levelling,
commonly used in mapping, both the difference in elevation and the horizontal distance between the points are
directly computed from the measured vertical angles and staff readings.
1.1.1 Spirit Levelling or Direct Levelling
It is that branch of levelling in which the vertical distances with respect to a horizontal line (perpendicular to the
direction of gravity) may be used to determine the relative difference in elevation between two adjacent points.
A horizontal plane of sight tangent to level surface at any point is readily established by means of a spirit level
or a level vial. In spirit levelling, a spirit level and a sighting device (telescope) are combined and vertical
distances are measured by observing on graduated rods placed on the points. The method is also known as direct
levelling. It is the most precise method of determining elevations and the one most commonly used by engineers.
Figure Error! No text of specified style in document..6 : Direct Levelling (Punmia, 2015)
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3494
www.rsisinternational.org
Dumpy level, automatic level and digital level are the typical instruments that are used in direct levelling
measurements (Tandon, 2013). Out of them, the automatic level is also termed as self-aligning level. It has a
compensator which consists of an arrangement of three prisms. The two outer ones are attached to the barrel of
the telescope. The middle prism is suspended by fine wiring and reacts to gravity. The instrument is first levelled
approximately by the circular bubble, the compensator then deviates the line of sight by the amount that the
telescope is out of sight (Tandon, 2013).
Important Terms in Levelling
Table Error! No text of specified style in document..1 : Terms in Levelling (Mishra, 2017)
Level Line
A line lying in a level surface. It is, therefore, normal to the plumb line at all points.
Horizontal Plane
A plane tangential to the level surface at that point. It is, therefore, perpendicular to the
plumb line through the point.
Horizontal Line
A straight line tangential to the level line at a point. It is also perpendicular to the plumb
line.
Vertical Line
A line normal to the level line at a point. It is commonly considered to be the line defined
by a plumb line.
Datum
Any surface to which elevation are referred. The mean sea level affords a convenient
datum world over, and elevations are commonly given as so much above or below sea
level. It is often more convenient, however, to assume some other datum, specially, if
only the relative elevation of points are required.
Elevation or
Reduced Level
The elevation of a point on or near the surface of the earth is its vertical distance above
or below an arbitrarily assumed level surface or datum. The difference in elevation
between two points is the vertical distance between the two-level surface in which the
two points lie. This is often denoted as reduced level.
Vertical Angle
Angle between two intersecting lines in a vertical plane. Generally, one of these lines is
horizontal.
Mean Sea Level
Average height of the sea for all stages of the tides. At any particular place it is derived
by averaging the hourly tide heights over a long period of 19 years.
Bench Mark
A relatively permanent point of reference whose elevation with respect to some assumed
datum is known. It is used either as a starting point for levelling or as a point upon which
to close as a check.
Line of
Collimation
A line joining the intersection of cross hairs of diaphragm to the optical centre of object
glass and its continuation. It is known as line of sight.
Back Sight
A staff reading taken at a known elevation. It is the first staff reading taken after setup of
instrument.
Fore Sight
Last staff reading taken denoting the shifting of the instrument.
Change Point or
Turning Point
Point on which both fore sight and back sight are taken.
Intermediate
Sight
Staff reading taken on a point where elevation is to be determined. All staff readings
between back sight and fore sight are intermediate sights.
Benchmarks
Bench mark is a point of known elevation (Punmia, 2015). There are several types of bench marks such as; GTS
(great trigonometrically surveyed bench mark), permanent bench mark, arbitrary bench mark, temporary bench
mark etc. as classified according to the purpose served by them.
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3495
www.rsisinternational.org
GTS Benchmark
The long form of GTS benchmark is Great Trigonometrical Survey benchmark. These benchmarks are
established by national agency. In Sri Lanka, the Survey Department is involved with such works. GTS
benchmarks are established all over the country with highest precision survey, the datum being mean sea level.
A bronze plate provided on the top of a concrete pedestal with elevation engraved on it serves as benchmark. It
is well protected with masonry structure built around it so that its position is not disturbed by animals or by any
unauthorized person. The position of GTS benchmarks are shown in the topo sheets published (Punmia, 2015).
Permanent Benchmark
These are the benchmarks established by state government agencies like PWD. They are established with
reference to GTS benchmarks. They are usually on the corner of plinth of public buildings.
Arbitrary Benchmark
In many engineering projects the difference in elevations of neighbouring points is more important than their
reduced level with respect to mean sea level. In such cases a relatively permanent point, like plinth of a building
or corner of a culvert, are taken as benchmarks, their level assumed arbitrarily such as 100m, 300m etc.
Temporary Benchmark
This type of benchmark is established at the end of the day’s work, so that the next day work may be continued
from that point. Such point should be on a permanent object so that next day it is easily identified.
Total Station
A Total Station is modern, automated and much more complicated combination of theodolite integrated with an
electronic distance meter (EDM), microprocessor with an internal data storage or external data collector. The
total station is designed for measuring of slant distances, horizontal and vertical angles (earlier theodolite was
used for this purpose) and elevations in topographic and geodetic works as well as for solution of application
geodetic tasks. Like every optical and electro-mechanical instrument total station does have some source of error
that need to be understand and instrument must be calibrated before the instrument move to field (Mishra, 2017).
Sources of Errors in Total Station Levelling (Mishra, 2017)
1. Compensator index error: Errors caused by not levelling a theodolite or total station carefully cannot be
eliminated by taking face left and face right readings. If the total station is fitted with a compensator, it will
measure residual tilts of the instrument and will apply corrections to the horizontal and vertical angles for
these. However, all compensators will have a longitudinal error l and traverse error t known as zero-point
errors. These are averaged using face left and face right readings but for single face readings must be
determined by the calibration function of the total station.
2. Horizontal collimation error: Horizontal collimation error exists when the optical axis of the total station
instrument is not exactly perpendicular to the telescope axis. To test for horizontal collimation error, point
to a target in face one then point back to the same target in face two, the difference in horizontal circle
readings should be 180 degrees. Horizontal collimation error can always be corrected for by meaning the
face left and face right pointing of the instrument.
3. Height of standards error: In order for the telescope to plunge through a truly vertical plane the telescope
axis must be perpendicular to the standing axis. As stated before, there is no such a thing as perfection in the
physical world. All theodolites have a certain degree of error caused by imperfect positioning of the telescope
axis. Generally, determination of this error should be accomplished by a qualified technician because
horizontal collimation and height of standards errors interrelate and can magnify or offset one another.
Horizontal collimation error is usually eliminated before checking for height of standards. Height of
standards error is checked by pointing to a scale the same zenith angle above a 90-degree zenith in ‘face-
one’ and ‘face-two’. The scales should read the same in face one as in face two.
4. Tilting axis error: These axial errors occur when the titling axis of the total station is not perpendicular to
its vertical axis. This has no effect on sightings taken when the telescope is horizontal, but introduces errors
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3496
www.rsisinternational.org
into horizontal circle readings when the telescope is tilted, especially for steep sightings. As with horizontal
collimation error, this error is eliminated by two face measurements, or the tilting axis error a is measured in
a calibration procedure and a correction applied for this to all horizontal circle readings as before if a is too
big, the instrument should be returned to the manufacturer.
5. Vertical collimation error: A vertical collimation error exists on a total station if the 0° to 180° line in the
vertical circle does not coincide with its vertical axis. This zero-point error is present in all vertical circle
readings and like the horizontal collimation error, it is eliminated by taking FL and FR readings or by
determining.
6. Pointing errors: Pointing errors are due to both human ability to point the instrument and environmental
conditions limiting clear vision of the observed target. The best way to minimize pointing errors is to repeat
the observation several times and use the average as the results.
7. Uneven heating of the instrument: Direct sunlight can heat one side of the instrument enough to cause
small errors. For the highest accuracy, utilize an umbrella or pick a shaded spot for the instrument.
8. Vibrations: Avoid instrument locations that vibrate. Vibrations can cause the compensator to be unstable.
9. Atmospheric corrections: Meteorological data corrections to observed EDM slope distances may be
significant over longer distances. Usually for most topographic surveying over short distances, nominal
(estimated) temperature and pressure data is acceptable for input into the data collector. Instruments used to
measure atmospheric temperature and pressure must be periodically calibrated. This would include
psychrometers and barometers.
10. Optical plummet errors: The optical plummet or tri-brachs must be periodically checked for misalignment.
This would include total stations with laser plummets.
11. Adjustment of prism poles: When using prism poles, precautions should be taken to ensure accurate
measurements. A common problem encountered when using prism poles is the adjustment of the leveling
bubble. Bubbles can be examined by establishing a check station under a doorway in the office. First, mark
a point on the top of the doorway. Using a plumb bob, establish a point under the point on the doorway. If
possible, use a center punch to make a dent or hole in both the upper and lower marks. The prism pole can
now be placed into the check station and easily adjusted.
Research in Total Station Levelling
There are several studies that had been carried out to investigate the use of total station for levelling. Some of
them are described below.
The study done by Julius Geofrey, an undergraduate of Ardhi University in Tanzania, shows a comparison
between digital levelling and total station levelling. The levelling route is 7km long and consists four segments;
three 2km segments and a 1km segment. Benchmarks were established on the separation of each segment. In
addition, minor benchmarks were established in between those segments. The forward and back levelling were
run for each segment using both instruments and the loop misclosure was determined by subtracting the
computed reduced level from the known reduced level of the benchmark. The root mean squares of the observed
misclosure for each segment were in acceptable range both for the total station and digital level. However, they
found that digital level is more precise as usual. The study recommends to carry out further research on different
areas of interests with longer levelling routes in order to check the accumulation of errors in longer distances.
Another study has been done by Jongchool & Taeho, 2001, to investigate the application to levelling using total
station. This study mainly focuses on the effect of EDM error. The distance measured by EDM is expressed by
the formula;
S = U + mλ/2, where,
• U: phase shift of the reflected light wave
• λ: wavelength
• m: number of transmitted wavelengths
The device for measuring distance by light wave always should have the correction for the measured value. Here
they have studied mainly the weather correction and zero correction. Weather correction consists variables such
as refraction of atmosphere, height of sea level, refraction by projection method and difference of scale
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3497
www.rsisinternational.org
coefficient. Zero correction is influenced mainly by prism integer and error by incidence angle. The study area
they had chosen was a 650m long asphalt paved road in Busan, Korea. Topcon's GTS-701 total station was used
as the measurement device while Topcon's first-class levelling device was used for comparison. They have
observed that the maximum distance they could discriminate the prism's central point from the telescope lens
was 280m, and its error was 2.3mm that satisfies the second-class allowable error, 2.6mm. Therefore, it is judged
that if the distance is applied that can discriminate the prism's central point, it can satisfy the second-class
levelling.
Study Area and Methodology
Study Area
Figure Error! No text of specified style in document..7 : Study Area
The study area was chosen along Pambahinna-Rajawaka road (B593). This road is situated within Imbulpe
Divisional Secretariat, Ratnapura District, Sabaragamuwa Province. The road was exclusively designed for the
Samanalawewa Reservoir project. For this study, the section between 1km post and 9km post of the road was
selected. The beginning point is closer to university and the route is not congested by vehicular traffic except in
the area adjacent to University and Pambahinna junction. This route consists of both relatively flat areas and
undulated areas with many horizontal and vertical bends. Similar climatic conditions exists along the entire study
area.
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3498
www.rsisinternational.org
Figure Error! No text of specified style in document..8 : Elevation Profile
In the first two kilometers of study route, the road is relatively flat and long straight sections can be found there.
In the next three kilometers road becomes undulated with many horizontal and vertical bends. This area
moderately slopes downwards. In the next two kilometers, road extremely slopes downwards and consists of
sharp bends. The final kilometer climbs a hill with sharp bends again. There are huge gradients in the final three
kilometers of the route.
Instruments Used
• Auto Level (L-48)
• Total Station (530R)
Permanent Bench Marks
Monuments were established near kilometre posts along the selected path under study to be used as permanent
benchmarks of the level line. These were made up of concrete and provided by Faculty of Geomatics. They were
established in places where stable ground conditions were available and far enough from road as they would be
protected from vehicle movement.
Figure Error! No text of specified style in document..9 : Permanent Bench Marks
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3499
www.rsisinternational.org
Temporary Benchmarks
Temporary benchmarks were established within short durations where the job was of temporary in nature. The
procedure involved establishment of temporary benchmarks which were made from wood. The nail in wood was
used in each temporary bench mark.
Figure Error! No text of specified style in document..10 : Temporary Benchmark
Field Procedure
First, permanent benchmarks were established in suitable places near kilometre posts. These benchmarks were
monuments made up of concrete. They were provided by the Faculty of Geomatics. In the starting point, a
benchmark established by Faculty of Geomatics was already available. Then a level line was started from that
point to measure the heights of newly established benchmarks. Auto level was used for that along with other
necessary equipment.
While running the level line, temporary benchmarks were established between permanent benchmarks in regular
distances apart such as 500m, 250m and 100m.
Details of the Level Line
Table Error! No text of specified style in document..2 : Details of the Level Line
Section
Description
1st kilometre
1 TBM; 500m distance apart
2nd kilometre
3 TBMs; 250m distance apart
3rd kilometre
9 TBMs; 100m distance apart
4th kilometre
1 TBM; 500m distance apart
5th kilometre
1 TBM; 500m distance apart
6th kilometre
1 TBM; 500m distance apart
7th kilometre
3 TBMs; 250m distance apart
8th kilometre
9 TBMs; 100m distance apart
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3500
www.rsisinternational.org
Checking Collimation Error
Prior to establish the level line, an experiment was carried out to check the collimation error of the auto level
which was to be used for the establishment of level line along the selected path.
First a suitable flat land was selected for the task. A 20m straight line was marked on the ground. Then the two
corner points and the midpoint was marked clearly on that line. Two level plates were placed on the corner
points. The level instrument was set on the midpoint and staffs were held on corner points and staff readings of
corner points were taken.
Then a point is marked 4m distant towards one corner and instrument was shifted there. The staff readings were
taken for that point. Again, the instrument was shifted towards the opposite side 4m from midpoint. The staff
readings were taken for that point also.
The height differences were similar for the above three instances. Therefore, error of collimation was negligible
in following tasks.
Table Error! No text of specified style in document..3 : Collimation Error Measurements
Mid-point
Move 4m towards back sight
Move 4m towards fore sight
Back sight
1.335
1.315
1.284
Fore sight
1.390
1.370
1.339
Difference
0.055
0.055
0.055
Automatic Levelling
The level line was started from BM 01 established by Faculty of Geomatics near 1km post using Auto Level.
The arbitrary height was defined as 500m for BM1. Then the level line was continued until BM 09 near 9km
post. On the way, TBMs were established between permanent benchmarks while recording heights of all BMs
and TBMs. Three level plates were used while carrying out the level line.
After reaching BM 09, the flyback levelling was started there and continued towards BM 01. On the way, the
heights were recorded for all the BMs and TBMs. The heights of the BMs and TBMs were set after the flyback
of level line when it was assured that the error of misclosure is within allowable limit.
Checking Collimation Error for Total Station
This was conducted in the faculty premises. First a cross symbol was marked on a wall. Then the mark was
observed in face left and the angle was recorded. Again, that mark was observed using face right. The both angles
were nearly equal to 180 degrees. Therefore, collimation error was neglected for further activities.
Total Station Levelling
The starting point of level line was BM 01 established by Faculty of Geomatics. First the Total Station was setup
on BM1 and it was oriented to arbitrary north. Then the horizontal coordinates were set as (1000,1000) and
vertical coordinate as (500). Here, the instrument height was measured manually by tape and entered to Total
Station. The target pole was kept on a cement picket (CP 01) on a nearby point. Bipods were used to keep target
pole vertically. Target pole was a graduated one and height was set to 1.5m. The target height was entered in
Total Station. Then an observation was taken and recorded.
Then the Total Station was taken to CP 01 and Target Pole was kept on BM1. Here the instrument height is not
measured manually. Another observation was taken on target on BM 01 (back sight).
Then the vertical distance is displayed on the screen. This vertical distance was used in following formula to
calculate Total Station instrument height. This was manually entered as the instrument height on CP 01.
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3501
www.rsisinternational.org
Figure Error! No text of specified style in document..11 : Calculating the Instrument Height
Then CP 02 was established in a visible distance from CP 01. Target is kept over CP 02 and observation was
taken and recorded. This procedure was continued until the level line came to BM 02. On the way, heights of
temporary benchmarks were recorded.
Later, the same first kilometer was levelled again by changing the target height to 1.4m and 1.6m. For other 1km
long sections, Total Station levelling was performed separately setting the target height as 1.5m. The Total
Station levelling was carried out only for first three kilometers and final two kilometers. Because, those sections
were sufficient to cover various topographical conditions that are considered in this study.
Data Processing
Using Microsoft Excel the difference in elevation was determined by the formula shown below.
Difference in Elevation (ΔH) = Foresight (FS) - Backsight (BS).
The difference in elevation was used to calculate the height of a point along the levelling route. The reduced
level of the permanent benchmark and temporary benchmark was calculated and filled the table. It is shown in
the next chapter.
The data from total station levelling was used to create various tables and graphs that indicate error and error
variation using Microsoft word and Microsoft excel respectively for further analysis.
RESULTS, ANALYSIS AND DISCUSSION
Results and Analysis
First, the measurements from Auto Level were used to calculate the reduced levels of all the BMs and TBMs.
They were recorded in tables using MS Excel.
Table Error! No text of specified style in document..4 : Reduced Levels of BMs and TBMs
Station
Distance from starting point
(Km)
Height(m)
BM 01
0
500
TBM 01
0.5
481.743
BM 02
1
452.987
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3502
www.rsisinternational.org
TBM 02
1.25
449.168
TBM 03
1.5
438.535
TBM 04
1.75
437.26
BM 03
2
435.925
TBM 05
2.1
431.756
TBM 06
2.2
436.074
TBM 07
2.3
444.72
TBM 08
2.4
449.288
TBM 09
2.5
456.913
TBM 10
2.6
466.229
TBM 11
2.7
468.158
TBM 12
2.8
462.294
TBM 13
2.9
452.906
BM 04
3
449.266
TBM 14
3.5
423.335
BM 05
4
417.758
TBM 15
4.5
412.055
BM 06
5
405.038
TBM 16
5.5
370.251
BM 07
6
347.59
TBM 17
6.25
326.679
TBM 18
6.5
305.829
TBM 19
6.75
279.095
BM 08
7
278.22
TBM 20
7.1
286.348
TBM 21
7.2
293.956
TBM 22
7.3
302.925
TBM 23
7.4
310.005
TBM 24
7.5
317.017
TBM 25
7.6
323.796
TBM 26
7.7
332.615
TBM 27
7.8
343.59
TBM 28
7.9
356.559
BM 09
8
367.749
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3503
www.rsisinternational.org
Table Error! No text of specified style in document..5 : Summary of Misclosures for Selected Segments
Segment (With
Flyback)
Length
(km)
Allowable Misclosure
(mm)
Observed Misclosure
(mm)
Remarks
BM 01 – BM 02
2km
24
6
Observed
misclosure is
acceptable
BM 02 – BM 03
2km
24
1
Observed
misclosure is
Acceptable
BM 03 – BM 04
2km
24
9
Observed
misclosure is
Acceptable
BM 07 – BM 08
2km
24
16
Observed
misclosure is
Acceptable
BM 08 – BM 09
2km
24
4
Observed
misclosure is
Acceptable
Table Error! No text of specified style in document..6 : Reduced Levels from Total Station
Station
Distance from starting
point
(km)
Height (m)
T.H 1.4
T.H 1.5
T.H 1.5
T.H 1.6
BM 01
0
500
500
500
500
TBM 01
0.5
480.759
480.748
480.756
480.766
BM 02
1
452.026
452.026
452.025
452.028
TH = 1.5
TBM 02
1.25
449.158
TBM 03
1.5
438.528
TBM 04
1.75
437.293
BM 03
2
435.935
TBM 05
2.1
431.761
TBM 06
2.2
436.082
TBM 07
2.3
444.734
TBM 08
2.4
449.301
TBM 09
2.5
456.925
TBM 10
2.6
466.232
TBM 11
2.7
468.146
TBM 12
2.8
462.287
TBM 13
2.9
452.896
BM 04
3
449.262
BM 07
6
347.59
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3504
www.rsisinternational.org
TBM 17
6.25
326.692
TBM 18
6.5
305.839
TBM 19
6.75
279.13
BM 08
7
278.277
TBM 20
7.1
286.344
TBM 21
7.2
293.947
TBM 22
7.3
302.915
TBM 23
7.4
310.007
TBM 24
7.5
317.011
TBM 25
7.6
323.778
TBM 26
7.7
332.591
TBM 27
7.8
343.576
TBM 28
7.9
356.541
BM 09
8
367.693
Table Error! No text of specified style in document..7 : Summary of Misclosure for Total Station
Following comparisons were made accordingly. Variation of error along with target height and distance of level
line are also shown where appropriate;
Segment
Target
height (m)
Length
(km)
Allowable
Misclosure
(mm)
Observed
Misclosure
(mm)
Remarks
BM 01 – BM 02
1.4
1
24
961
Observed
misclosure is not
acceptable
1.5
(Set 01)
1
24
961
Observed
misclosure is not
acceptable
1.5
(Set 02)
1
24
962
Observed
misclosure is not
acceptable
1.6
1
24
959
Observed
misclosure is not
acceptable
BM 02 – BM 03
1.5
1
24
10
Observed
misclosure is
acceptable
BM 03 – BM 04
1.5
1
24
4
Observed
misclosure is
acceptable
BM 07 – BM 08
1.5
1
24
57
Observed
misclosure is not
acceptable
BM 08 – BM 09
1.5
1
24
56
Observed
misclosure is not
acceptable
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3505
www.rsisinternational.org
Segment 01 for Total Station
It has one temporary benchmark and two Permanent benchmarks named BM1 and BM2 with a separation
distance of one kilometer.
Segment 01 – Set 01 – BM 01 to BM 02
• Instrument – Total station (530R) and auto level (L-48)
• Target height – 1.4m
Table Error! No text of specified style in document..8 : Segment 01 – Set 01 – Reduced Level and Reduced
Level Difference
Station
Height (m)
Difference
(m)
Auto Level
Total Station
(T.H 1.4m)
BM 01
500
500
0
TBM 01
481.743
480.759
0.984
BM 02
452.987
452.026
0.961
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3506
www.rsisinternational.org
Figure Error! No text of specified style in document..12 : Auto Level and TS Elevation Profile in Segment 1
– Set 1
Figure Error! No text of specified style in document..13 : Error Variation in Segment 1 - Set 1
0
0.2
0.4
0.6
0.8
1
1.2
BM1 TBM1 BM2
Error
Point
Error++
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3507
www.rsisinternational.org
Segment 01 – Set 02 – BM 01 to BM 02
• Instrument – Total station (530R) and auto level (L-48)
• Target height – 1.5m
Table Error! No text of specified style in document..9 : Segment 01 – Set 02 – Reduced Level and Reduced
Level Different
Station
Height (m)
Difference (m)
Auto Level
Total Station (T.H 1.5m)
BM 01
500
500
0
TBM 01
481.743
480.748
0.995
BM 02
452.987
452.026
0.961
Figure Error! No text of specified style in document..14 : Auto Level and TS Elevation Profile in Segment 1
- Set 2
Figure Error! No text of specified style in document..15 : Error Variation in Segment 1 - Set 2
Segment 01 – Set 03 – BM 01 to BM 02
• Instrument – Total station (530R) and auto level (L-48)
0
0.2
0.4
0.6
0.8
1
1.2
BM1 TBM1 BM2
Error
Point
Error
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3508
www.rsisinternational.org
• Target height – 1.5m
Table Error! No text of specified style in document..10 : Segment 01 – Set 03 – Reduced Level and Reduced
Level Difference
Station
Height (m)
Difference
(m)
Auto Level
Total Station (T.H 1.5m)
BM 01
500
500
0
TBM 01
481.743
480.756
0.987
BM 02
452.987
452.025
0.962
Figure Error! No text of specified style in document..16 : Auto Level and TS Elevation Profile in Segment 1
– Set 3
450
455
460
465
470
475
480
485
490
495
500
TS Height
Point
TS Height
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3509
www.rsisinternational.org
Figure Error! No text of specified style in document..17 : Error Variation in Segment 1 - Set 3
Segment 01 – Set 04 – BM 01 to BM 02
• Instrument – Total station (530R) and auto level (L-48)
• Target height – 1.6m
Table Error! No text of specified style in document..11 : Segment 01 – Set 04 – Reduced Level and Reduced
Level Difference
Station
Height (m)
Difference
(m)
Auto level
Total station (T.H 1.6m)
BM 01
500
500
0
TBM 01
481.743
480.766
0.977
BM 02
452.987
452.028
0.959
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3510
www.rsisinternational.org
Figure Error! No text of specified style in document..18 : Auto Level and TS Elevation Profile in Segment 1
– Set 4
Figure Error! No text of specified style in document..19 : Error Variation in Segment 1 - Set 4
In the first segment, direction and gradient of the slope is relatively uniform. Total Station levelling was
conducted twice for this segment using same target height; one in morning and the other one in evening (Tables
4.6 and 4.7). The results were similar for both tasks.
First segment was levelled using Total Station three times for different target heights; 1.4m, 1.5m and 1.6m. The
results were similar for all these target heights as shown in tables above (Table 4.5, 4.6, 4.7 and 4.8).
Only one TBM was set in the midpoint of the segment at 500m distance from starting point. Very large horizontal
distances were set between instrument and target while levelling this segment using Total Station as good inter-
visibility was available for such long distances. And it was helpful to carry out the task rapidly. Some distances
were longer than 100m. The error of Total Station levelling was very much larger than the acceptable error
(Table 4.2).
1.1.2 Segment 02 for Total Station
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3511
www.rsisinternational.org
It has three temporary benchmark and two Permanent benchmarks named BM 02 and BM 03 with a separation
distance of one kilometer.
Segment 02 – BM 02 to BM 03
• Instrument – Total station (530R) and auto level (L-48)
• Target height – 1.5m
Table Error! No text of specified style in document..12 : Segment 02 – Reduced Level and Reduced Level
Difference
Figure Error! No text of specified style in document..20 : Auto Level and TS Elevation Profile in Segment 2
Station
Height (m)
Difference
(m)
Auto Level
Total Station
BM 02
452.987
452.987
0
TBM 02
449.168
449.158
0.01
TBM 03
438.535
438.528
0.007
TBM 04
437.26
437.293
-0.033
BM 03
435.925
435.935
-0.01
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3512
www.rsisinternational.org
Figure Error! No text of specified style in document..21 : Error Variation in Segment 2
The slope of this segment was varying in a wider range compared with segment one as shown in Figure 4.9.
TBMs were set in 250m distances apart in this segment. Though the error was within acceptable range for the
entire segment, error was not acceptable for TBM 04 and it was larger than the acceptable error for entire segment
(Table 4.9). TBM 04 was located at the bottom of a slope and the elevation is increasing towards BM 04 from
that point.
Segment 03 for Total Station
Segment 03 – BM 03 to BM 04
• Instrument – Total station (530R) and auto level (L-48)
• Target height – 1.5m
Table Error! No text of specified style in document..13 : Segment 03 – Reduced Level and Reduced Level
Difference
Station
Height (m)
Difference
(m)
Auto Level
Total Station
BM 03
435.925
435.925
0
TBM 05
431.756
431.761
-0.005
TBM 06
436.074
436.082
-0.008
TBM 07
444.72
444.734
-0.014
TBM 08
449.288
449.301
-0.013
TBM 09
456.913
456.925
-0.012
TBM 10
466.229
466.232
-0.003
TBM 11
468.158
468.146
0.012
TBM 12
462.294
462.287
0.007
TBM 13
452.906
452.896
0.01
BM 04
449.266
449.262
0.004
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3513
www.rsisinternational.org
Figure Error! No text of specified style in document..22 : Auto Level and TS Elevation Profile in Segment 3
Figure Error! No text of specified style in document..23 : Error Variation in Segment 3
TBMs were set in 100m distances apart in this segment. Therefore, distance between instrument and target was
less than 100m in every instance. This segment consists a hill with slope rising and falling in a fairly constant
gradient.
410
420
430
440
450
460
470
480
ON BM 03
ON TP
ON TBM 05
ON TP
ON TP
ON TP
ON TBM 07
ON TP
ON TP
ON TP
ON TBM 09
ON TP
ON TP
ON TP
ON TBM 11
ON TP
ON TP
ON TP
ON TBM 13
ON TP
L.Height
Point
L.Height
410
420
430
440
450
460
470
480
BM3
CP1
TBM5
CP2
TBM6
TBM7
CP3
TBM8
CP4
TBM9
CP5
TBM10
TBM11
CP6
TBM12
CP7
TBM13
CP8
BM4
TS Height
Point
TS Height
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3514
www.rsisinternational.org
Error is acceptable for entire segment and for every TBM except for certain TBMs (Table 4.10). Error variation
is different by place to place as indicated in Figure 4.12.
1.1.3 Segment 04 for Total Station
It has three temporary benchmark and two Permanent benchmarks named BM7 and BM8 with a separation
distance of one kilometer.
Segment 04 – BM 07 to BM 08
• Instrument – Total station (530R) and auto level (L-48)
• Target height – 1.5m
Table Error! No text of specified style in document..14 : Segment 04 – Reduced Level and Reduced Level
Different
Figure Error! No text of specified style in document..24 : Auto Level and TS Elevation Profile in Segment 4
Station
Height (m)
Difference
(m)
Auto Level
Total Station
BM 07
347.59
347.59
0
TBM 17
326.679
326.692
-0.013
TBM 18
305.829
305.839
-0.01
TBM 19
279.095
279.13
-0.035
BM 08
278.22
278.277
-0.057
250
260
270
280
290
300
310
320
330
340
350
ON BM 07
ON TP
ON TP
ON TP
ON TP
ON TP
ON TBM 17
ON TP
ON TP
ON TP
ON TP
ON TBM 18
ON TP
ON TP
ON TP
ON TP
ON TP
ON TBM 19
ON TP
ON TP
ON TP
ON TP
ON BM 08
L.Height
Point
L.Height
250
260
270
280
290
300
310
320
330
340
350
TS Height
Point
TS Height
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3515
www.rsisinternational.org
Figure Error! No text of specified style in document..25 : Error Variation in Segment 4
TBMs were set in 250m distances. This segment consists a slope downwards with a huge gradient except in final
part and several sharp bends. Error was not acceptable for the whole segment (Table 4.11). All errors were in
minus side (Figure 4.14).
Segment 05 for Total station
It has nine temporary benchmark and two permanent benchmarks named BM8 and BM9 with a separation
distance of one kilometer.
Segment 05 – BM 08 to BM 09
• Instrument – Total station (530R) and auto level (L-48)
• Target height – 1.5m
Table Error! No text of specified style in document..15 : Segment 05 – Reduced Level and Reduced Level
Difference
Station
Height (m)
Difference
(m)
Auto Level
Total Station
BM 08
278.22
278.22
0
TBM 20
286.348
286.344
0.004
TBM 21
293.956
293.947
0.009
TBM 22
302.925
302.915
0.01
TBM 23
310.005
310.007
-0.002
TBM 24
317.017
317.011
0.006
TBM 25
323.796
323.778
0.018
TBM 26
332.615
332.591
0.024
TBM 27
343.59
343.576
0.014
TBM 28
356.559
356.541
0.018
BM 09
367.749
367.693
0.056
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3516
www.rsisinternational.org
Figure Error! No text of specified style in document..26 : Auto Level and TS Elevation Profile in Segment 5
Figure Error! No text of specified style in document..27 : Error Variation in Segment 5
TBMs were set in 100m distances apart and the segment rises upwards towards BM 09. The gradient of slope
was very high (Figure 4.15). This segment also consists of sharp bends. Therefore, distance between instrument
and target was always less than 100m. Error exceeds acceptable limit in this segment also (Table 4.12) and all
are in plus side (Figure 4.16).
250
270
290
310
330
350
370
390
ON BM 08
ON TP
ON TP
ON TP
ON TP
ON TP
ON TP
ON TP
ON TBM 23
ON TP
ON TBM 24
ON TP
ON TBM 25
ON TP
ON TP
ON TP
ON TP
ON TBM 27
ON TP
ON TP
ON TBM 28
ON TP
ON TP
ON BM 09
L.Height
Point
L.Height
250
270
290
310
330
350
370
390
BM8
CP1
TBM20
CP2
TBM21
CP3
TBM22
CP4
CP5
TBM23
CP6
TBM24
TBM25
CP7
TBM26
TBM27
CP8
TBM28
BM9
TS Height
Point
TS Height
INTERNATIONAL JOURNAL OF RESEARCH AND SCIENTIFIC INNOVATION (IJRSI)
ISSN No. 2321-2705 | DOI: 10.51244/IJRSI |Volume XII Issue IX September 2025
Page 3517
www.rsisinternational.org
CONCLUSION AND RECOMMENDATIONS
Conclusion
There were no much considerable effects to the error from weather in this study as total station levelling was
conducted twice in different parts of the day for same target height and same segment and similar results were
obtained. The effect of climate is uncertain in this study as this was carried out along a level line that passes
areas with similar climatic conditions.
Also, the readings were similar for three different target heights for same segment. Therefore, it can be assumed
that target height does not do much effect to error in total station levelling. It is remarkable that error generation
is high when the distance between instrument and target is longer. The first segment is an example for that.
According to the results in 4th and 5th segments, error generation is high when the slope is high. Therefore, it
can be assumed that error in total station levelling has some relation with slope. Error was almost positive when
the elevation rises along a hill and negative when elevation decreases along a slope. Error of misclosure was
acceptable in segments where the gradient of slope is low and shorter distances were set between instrument and
targets.
Recommendations
A good analysis can be done regarding error variation when the number of TBMs is high. Therefore, the density
of TBMs should be increased in order to find a better relation of error with relevant error factors in total station
levelling. Total station levelling cannot be recommended for water supply and drainage projects where high
accuracy and precision is required because error variation is different from place to place.
LIST OF REFERENCES
1. COMET. (2015, March 31). Online Course - Understanding Heights and Vertical Datums. Retrieved
from Comet - MetEd Education and Training: https://learn.meted.ucar.edu/#/online-course-
player/981233d9-353e-4709-9bbf-93f2bc7e0e8e
2. Geofrey, J. (n.d.). Comparison Between Digital Levelling and Total Station Levelling. Academia.edu.
3. Lee, J., & Rho, T. (2001). Application to Leveling Using Total Station. In New Technology for a New
Century International Conference FIG Working Week 2001. : . New Technology for a New Century
International Conference FIG Working Week 2001. Seoul, Korea: FIG Conference Proceedings.
4. Mishra, G. (2017). Error Sources in Total Station in Surveying. Retrieved from The Constructor:
https://theconstructor.org/surveying/error-sources-in-total-station/6052/
5. NOAA. (2016). Retrieved from National Geodetic Survey: https://www.ngs.noaa.gov/datums/
6. Punmia, B. (2015, August). Levelling. Retrieved from Civil Blog:
https://www.civilblog.com/levelling/
7. Tandon, G. H. (2013, October 6). Levelling. Slideshare.
