Final Report

DEPARTMENT OF SPATIAL SCIENCES

SPECIAL SURVEYS AREAS

Philippe Olivier Maurel

13591571

“This thesis is presented as part of the requirements for the award of the Degree

of Surveying of the Curtin University of Technology”

1

Acknowledgements

I would like to thanks Mr. Tony Snow, my supervisor for his advice and support during the

course of this project. Tony Boylan from Cottage and Engineering Surveys gave provided

constructive practical advice during the scope of this project to which I am very thankful.

Cottage and Engineering Surveys also provided a car and much of the equipments required

for the project. Curtin University provided the software and the total station and GNSS

receivers. Without their held this project would not have been possible. I would like to show

my gratitude to John Walker, from the survey store at Curtin University has been very patient

and understanding regarding the lending of the university equipment. Rich Coldan and Rod

McKinney, inspecting surveyors at Landgate, have provided invaluable guidance and are

responsible for the laughing of this fourth year project. Lastly I am heartily thankful Paul

Connor, who has proven to be a great working colleague during this project. Paul took care of

most of the GNSS component of the Project while I directed the cadastral component. This

proven to be a great combination has the project always worked smoothly.

2

Table of Contents

Acknowledgements..................................................................................................................................2

Introduction..............................................................................................................................................4

Material and Methods..............................................................................................................................6

Equipment list......................................................................................................................................6

Survey Mark Audit..............................................................................................................................6

Total Station Surveys (Surround Survey)............................................................................................7

GNSS surveys......................................................................................................................................7

Adjustment of plate bubble and optical plummet................................................................................9

Traffic Management............................................................................................................................9

Class of the networks...........................................................................................................................9

Processing of the GNSS surveys.......................................................................................................10

Minimally constrained network.........................................................................................................11

Carramar........................................................................................................................................11

Munster..........................................................................................................................................12

Aveley............................................................................................................................................12

Secret Harbour (old and new)........................................................................................................12

Fully constrained network.................................................................................................................13

Results....................................................................................................................................................14

Survey Mark Audit............................................................................................................................14

Total Station Surveys (Surround Survey)..........................................................................................15

Munster..........................................................................................................................................15

Carramar........................................................................................................................................16

Aveley............................................................................................................................................16

Secret Harbour new and old...........................................................................................................17

GNSS surveys....................................................................................................................................18

Carramar........................................................................................................................................18

Munster..........................................................................................................................................19

Aveley............................................................................................................................................20

Secret Harbour...............................................................................................................................21

Conclusion.............................................................................................................................................23

References..............................................................................................................................................26

Appendix................................................................................................................................................27

3

Introduction

The creation of Special Survey Area (SSA) regulations in 2001 was done in an effort to

improve the efficiency and reliability of cadastral boundaries re-establishment for those areas

in the future.

The Survey Practice Guidelines for Subdivisions within Special Survey Areas are the

guidelines to refer to when dealing with SSAs. These guidelines are an update of the

regulation 10 of the Transfer of Land (Surveys) Regulations 1995 and should be followed for

matters relating to plans and the methods to be followed for the creation and presentation of

plans for an SSA. The regulation 26A of the licensed Surveyors (Guidance to Surveyors)

regulation 1961 should also be followed in conjunction with these guidelines when creating

an SSA (LSLB, 2006).

The new guidelines also replaces the guidelines for Urban Subdivisions under Regulations

55A-55F of the Licensed Surveyors (Guidance to Surveyors) Regulations 1961 previously

approved by the Licensed Surveyor Licensing Board (LSLB, 2006).

As a number of these SSAs are now aging, having gone through development and routine

maintenance, the placement and longevity of reference marks placed can be tested.

This research project seeks analyse the efficiency and accuracy achievable for re-establishing

cadastral boundaries in five different SSAs. Namely, the project will analyse the ease of

which boundary re-establishment can be achieved within each SSA by:

1. Carrying an Audit of the Survey Marks within a section of each SSA

An audit provides information on the longevity, indivisibility (placement), location and

accuracy for different survey marks used. Such information should help pinpointing bad

surveys practices and future choice of permanent survey marks. The density of the mark for

each SSAs will also be assessed.

4

2. Surround surveys

A surround survey will be used to asses if the plans distances and angles agreed within the

regulatory limit. For instance, the plan distances should agree with the measured distance by

no more than:

K=F√0.04 + S2; where:

- K in millimetres

- S is the direct distance between two points in kilometres

- and F is a fixed variable depending on the survey marks (could be 60 or 90).

The angles accuracy will also be assessed.

3. GNSS surveys

A GNSS surveys was carried out for 2 points in each SSAs in order to access any swing in

the network. The mark occupied were bass plaques set in concrete (Appendix A) and were

usually protected by a concrete hatch cover. Such marks could be turned into SSMs using the

observation procedures that were being followed during the survey.

4. Repeg check

In Aveley it was noticed that a surveyor had just recently done a repeg on a vacant block. The

accuracy of the corner pegs put were assessed using a three point alignment as required by

the Regulation 23 of the Licensed Surveyors (Guidance to Surveyors) Regulations 1961.

5

Material and Methods

Equipment list

- 1 SOKKIA total station (SET 1X)

- 2 reflectors SOKKIA (SP 726648)

- 3 SOKKIA wooden tripods (ref. 751252)

- 2 plum bobs

- 2 mini prism

- 1 400 mm prism pole

- 1 8 m measuring tape

- 1 50 m cloth tape

- 1claw hammer

- 1 axe

- 2 shovels

- 1 can of marking paint (white)

- 8 traffic cones

- 1 non-reflective ‘survey crew’ sign

- 2 safety vests

- 1 flagging tape

- Reflective tape, leather tool bag

- Survey marks (including R/S, S/H, D/S, Spike and Pens

Survey Mark Audit

The survey mark audit was mainly done to access the longevity, indivisibility, density and

quality of the survey mark. The audit was done using a shovel, a fifty metre cloth tape and

eight metre offset tape. All the marks in the study area was looked for and accessed.

Total Station Surveys (Surround Survey)

The total Station was calibrated on the Curtin baseline before the field work. The certificate

confirm that the instrument, a Sokkia Set 1 X (no. 4) passed all the test and was within the

regulation set by the Licensed Surveyors (Guidance to Surveyors) Regulations 1961

(Appendix). The angle observation was done following standard surveys practices. That is

6

each angle was an average of three arcs, always sighting the longest line first. The distances

were an average of five distance measurements. The distances and angle measurements were

done with the calibrated pair of total station and prism. However, mainly for buried spike the

distance and angle were measured to a plumb bob a mini prism because it was too time

consuming to set a target on so many points. When this was done the prism constant had to

be changed to 0mm (from -30 mm). In such instance great care was taken when measuring

angles and distances. QUICKCLOSE was used extensively during the survey work to

calculate the needed bearings and radiations and to perform Bowditch adjustment. The results

from the surveys are presented in the form of field notes (Appendix). The making of field

notes was kept in a neat and professional manner, and indexed and referenced in such a way

that a draftsman may be able to prepare a plan therefrom. Minute figuring or lettering was

avoided. Field notes were recorded in pencil in the field and inked after. Such practice is

conforming to the regulation (Regulation 10 amended in Gazette 26 October 1990). Only

black or blue-black ink (and in some instance red ink) was used throughout. However, for the

purpose of this project red and yellow inks were also used to accentuate the differences

between various measurements.

GNSS surveys

The successful completion of the task required thought out planning of network geometry,

observation time and field methodology, preparation for the use of instruments and software.

The network geometry was designed so that elongated triangles were avoided and that the

distance between the points did not significantly differ. In some instance, for example in

Munster the network was elongated due to a few available SSMs in the vicinity of the SSA.

In Munster the lines were observed for an extra 10 mins in order to increase the redundancy

of the observation. No Skyplots and time planning were done during the planning process due

the GNSS receiver reading to GLONASS (21 Satellites) and GPS satellite (29 satellites). So

many of satellites offer a permanent minimum required constellation of at least four satellite

and the DOPs are keep to a minimum. Moreover, most surveyors in the industry do not time

plan their survey or do sky plot anymore due to the significant increase in orbiting satellites

that occurred in the last decade. Five years ago, when GLONASS was not yet used, sky plots

and planning were certainly required.

7

The marks were chosen were brass plaque set in concrete. Other criteria were also regarded

as important such as:

safety of the surveyor and public,

the mark should be in close proximity to the anticipated work area,

the long term stability and permanence of the mark,

intervisibility to at least one adjacent SSM,

the ideal spacing between adjacent SSMs is 500 m to 5 km,

here should be no significant obstructions intruding into the space formed by a

cone 15° above the horizon,

avoid placing the mark close to a strong radio transmitter or under high voltage

power lines

Testing surveyors GNSS systems on the Curtin Calibration Network is advised but is rarely

done by surveyors. It was assume that due to the complexity of the GNSS processing a faulty

GNSS receiver will provide an easily detectable gross error. Moreover, during the loop

closure analysis a gross error would stand out. The only error that could not be accounted for

is the phase centre error. The point measured in GPS surveying is assumed to be the phase

centre of the GPS receiver's antenna. However, the phase centre is not a physical centre. The

offset and variation of a GPS receiver's antenna can be determined using anechoic chamber

measurements or using GPS observational data. The antenna was always orientated to the

north (any other orientation could have been chosen) in order to cancel most of the phase

centre error (in the sub-mm order).

The GPS observation was termed rapid static, with one point observed for a 10 minutes + 1

minutes/km for L1+L2 receivers up to 20 km. When consecutive baselines were observed at

one point the antenna height was changed by approximately 0.1 m each time as

recommended by SP1 where practical. Some baselines were observed longer if it was thought

that multipath may degrade the accuracy of the baseline. All the SSMs where assumed to be

accurate due to a time constrain. However, the standard practice would be to check each SSM

against their reference marks.

8

Adjustment of plate bubble and optical plummet

All the instruments where checked thoroughly before the field work, the plate and circular

bubbles where adjusted where needed and the optical plummets were checked.

Traffic Management

Roadworks can create potential hazards that can give rise to injury or damage resulting in

loss, litigation or prosecution, if reasonable care is not taken to protect both road users and

road workers. Moreover, the insurer will not cover accidents resulting from non-conform

traffic control procedures by a non-certificated traffic person. All the survey work was carried

out following the standards and procedures listed in Traffic Management for Work on Road,

Code of Practice (2009).

Class of the networks

CLASS is a function of the planned and achieved precision of a survey network (SP1, 2007). The

project aimed to achieve class A precision observation which requires that 20 % of points

within the network had 3 or more baselines observed from them and that the remaining points

had no less than two baselines observed to them, SP1 also stipulates that:

Formula 1: r = c (d + 0.2) mm at 1 σ

where;

r= length of maximum allowable semi-major axis in mm

c=an empirically derived factor represented by historically accepted precision for a particular

standard of survey

d= distance to any station in km

9

From SP1 (2007)

Processing of the GNSS surveys

The GPS log files where extracted from the GRS2700 ISX receivers using Sokkia’s GNSS

processing software ‘Spectrum Survey’ version 4. Baselines were reduced in spectrum after

having antenna height information added to the observations. Following SP1 guidelines a

mask of 15° was applied, the process interval was set as low as possible, a HDOP maximum

value of 10 was applied and only L1 data was used for solution because there is less noise

(compared to L1 and L2 combined). The baseline where bought to Microsearch GEOLAB

2001 to be processed in an adjustment to obtain the class of the survey (minimally

constrained) and obtain the required coordinates (fully constrained). In Microsearch

GEOLAB the data was processed any flagged outlier was analysed and checked against the

field notes. Some antenna heights were changed at this stage. A variance factor test at 95 %

confidence level was run for each adjustment, if the variance test was too low, it indicated a

pessimistic covariance matrices, all 3d coordinate differences were scaled equally as they are

the same observation type and affect one another. The covariance matrices were scaled down

by a factor based on the variance factor, in this study in varied between 1 and 0.2 mostly

depending on the order of the SSMs used. Inspecting the relative error ellipses it was found

that most were around 3 mm except for Aveley which had semi-major axis in the order of 10

mm. However, in Aveley the SSMs themselves do not seem to be accurate with semi-major

axis in the order of 10 mm as well (minimally constrained adjustment, Appendix).

10

Minimally constrained network

A minimally constrained adjustment is a least squares adjustment of all observations in a

network with attached a-priori variances (determined by the surveyor) where the only

constraints are those necessary to achieve a solution (SP1, 2007).

The minimally constrained network is used to access the internal consistency of a survey; it is

therefore required before the fully constrained adjustment. Different survey purpose/design

will dictate which parameters to fix. It is usually better to fix a SSMs with a higher order that

the others, and if two SSMs of the same order exist in the network that closest one to the

centre of the network is usually fixed.

Comparison of the relative error ellipses from the minimally constrained adjustment (see

Appendix) to the allowable error ellipse size revealed that the survey conforms to class A

(Table 2). The error ellipses major axes were less than the allowable value derived from

formula 1. The other criteria of class A were also satisfied by the networks. Ultimately the

derived stations will be of third order because the new observations cannot achieve a class

higher than the existing network the tie into (i.e., even if the survey observations achieve

class A standard if the SSMs used are class B, then the survey would be B). Moreover, Class

is also a function of the survey methods, instruments and reduction techniques used in that

survey. In the following tables are listed the major lines in each network.

Carramar

Table 1: Semi-major axis error allowable

Approximate distance Allowable error (mm)

68%.

Observed

error (mm)

From To Class A Class C

SSM 13A PSM east 15 62 11

SSM 42 PSM east 10 39 9

SSM 1 PSM east 15 59 10

PSM west PSM east 11 43 8

11

Munster



68%.

Observed

error


SSM 114 Nth PSM 16 54 4

SSM 114 Sth PSM 15 62 5

Nth PSM Sth PSM 3 13 3

SSM 14 Nth PSM 5 20 3

Aveley



68%.

Observed

error


SSM 9 Sth PSM 16 63 7

SSM 26 SSM 1 32 126 6



Secret Harbour (old and new)



68%.

Observed

error






12

Fully constrained network

The fully constrained network adjustment is subjected to the same analysis as the above

minimally constrained adjustment. It enables the orderly integration of the network with the

database containing the existing data set of established coordinates (i.e. SSM) (SP1, 2007). In

other words in ‘forces’ the network by finding coordinates for the new points that is best fitted to

the present observation and the fixed control.

For the fully constrained solution all the SSMs in the network were held fixed and the

adjustment was run again. The weighting of the observation from the minimally constrained

network were far too high which was expected as our observation conformed to class A, had

very small residuals and large weights yet Microsearch GEOLAB was trying to fit these

observations to a much less accurate network of lesser order. This was particularly true for

Aveley where the SSMs seem to be wrongly referenced by a few mm. The covariance matrix

scale factor was increases accordingly:

Table 5: Factors by which the covariance matrix was scaled up for the minimally and fully

constrained adjustment

Covariance Matrix Scale factor Fully constrained variance

factor at 95 % confidence

level

Minimally const. Fully constrained

Carramar 1 5 1.0433

Munster 0.2 6 1.2901

Aveley 0.6 15 1.1539

Secret Harbour 0.2 0.8 1.1559

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Results

Survey Mark Audit

The survey marks audits are presented in the appendix in the form of a spread sheet (first

page in each folder). Great care must be taken by a surveyor that his field notes show

everything he does or finds to exist on the ground. The summary of this audit are presented in

Table 6.

Table 6: Summary Statistic from the audits done in different SSAs.

% of

marks

missing

% of

marks in

bitumen

% mark

that remains

after

resurfacing

Rating of

the SSA

Notes

Munster 36 63 18 Very poor Would be hard to re-establish

boundaries in the future

S. Harbour

(New)

15 30 45 ok Could re-established boundary. But

most of the marks accounting for

the % that remain after resurfacing

are 3rd order marking. I.e., they

were established from PCM or

PSM. The accuracy is therefore

limited.

S. Harbour

(Old)

13 55 38 ok Could re-established boundary

Aveley 13 20 69 excellent An old area with good marking

Carramar 13 52 40 good The marks remaining are very

stable and of good order. More over

extra field books are available for

the establishment of this 1st SSA

and the marks remaining are

certainly higher.

* Marks in bitumen are considered ‘non-permanent’. I.e. the marks will disappear when the road will be

resurfaced.

14

It is important to note here that the older SSAs, namely Carramar and Aveley obtained a

better rating than any of the more recent SSAs (Table 6). Munster the most recent SSA had a

very poor rating and the lowest mark density making it the worst SSA when compared to the

other four SSAs (Table 6 and 7).

Table 7: Density of the Survey Marks in the DPs used.

Area Mark per block Year Average block size (m2) DP used

Carramar 0.77 2001 650 26897

Aveley 0.71 2004 650 42088/41391

S. Harbour Old 0.8 2006 550 49261

S. Harbour New 0.8 2008 500 526684/47046

Munster 0.24 2008 600 57023/57024

Total Station Surveys (Surround Survey)

The total station surveys results are presented in the form of field notes in the appendix. All

the survey transverses closed within the limit of 1’ as set per the regulation and a miscloses

well within of the 1: 8000 set by the regulation. The Angular miscloses were

distributed evenly between angles unless there is good reason to the

contrary. The linear miscloses were distributed according to the Bowditch

Rule:

‘As the total length of the traverse is to the length of each line, so is the

whole error in latitude or departure to the correction of the corresponding

latitude or departure, each correction being so applied as to diminish the

whole error in latitude or departure’ (Licensed surveyor act 1909).

However, in most SSA, the miscloses were so insignificant that it would

not change the survey in anyway. In fact Bowditch was used for the first

survey only.

Munster

The positional accuracy between the marks was poor with most marks agreeing with the

Deposited plan distance to a maximum of 7 mm. From the Licensed Surveyors (Guidance of

Surveyors) Regulations 1961, we known that distances shall be recorded in metres to the

15

nearest 0.005 metre except that for short lengths where circumstances require greater

accuracy, such as distances to offsets, reference marks, buildings and structures, etc., values

should be recorded to the nearest millimetre. Such accuracy is therefore outside the nearest 5

mm tolerance. However, it is within regulation as K, the maximum allowable distance

discrepancy is:

Table 8: Allowable errors in plan (using K=F√0.04 + S2).

Distance Plan distances should agree with measured distance by:

F=60 F=90

50 12 mm 18 mm

100 12 mm 18 mm

150 12 mm 18 mm

200 12 mm 18 mm

A deck spike measures about 12 mm in diameter and 7 mm difference is poor given the

access to modern instrumentation. There was also a gross error in one deck spike and many

of the angles (see field book).

Carramar

The distances and angles agreed with the originals within a few millimetres. The maximum

error in distance was five millimetres but most distances agreed to one or two millimetres

with the original. There was a problem with the IP in the north east corner of the surround

survey. It seems that the original IP (a ramset nail) has since been replaced by a screw that is

out of position in the east-west direction but was found to be correct in the north south

orientation. The correct location of the IP was then determined using the other available

marks. Page 2 of the Field Book shows how the re-established of the IP was done.

Aveley

All the marking in this SSA agreed with the original in terms of angles and distances. The

only problems seems to be with the buried spike that have suffered from repetitive digging by

surveyors, reticulation pipes, or have been disturbed by machinery. The difference is however

16

not great (in the order of 2-6 mm) in is not of great concern. Such error is expected for spikes

and could only be corrected by:

- Pouring some cement around the spike during their establishment

- Burring the spike deeper (at around 0.4 metres)

- Protecting the spikes with other spikes as done in older areas (not done in any SSAs)

It is important to note that the verge portions in SSAs are very small when compared to older

suburb around the Perth metropolitan area. The IP is often located in an area no bigger than a

few square metres between the path and the road. Such area becomes the area of choice, in

fact the only area, to plant a tree or to park a car. The disturbance to a spike situated only 0.3

m underground is therefore almost inevitable. Moreover, the Perth Basin is represented by

thin, impermanent sand dune systems, biogenic limestones, sandstones and some shales, all

are of sedimentary origin and unstable. A buried spike in those areas does not hold as well as

a buried spike in the swan valley or the Perth hills that are covered with a thick layer of clay.

The repeg of the Lot 293 in Ridley road was found to be correct with the biggest difference

being 6 mm. The western corner could not be observed without traversing due to the presence

of a brick pillar. This corner was not observed.

Secret Harbour new and old

Most of the marking is very good for this area. The biggest discrepancy was around 7 mm.

Again, the buried spikes are problematic with most of them differing from the original by

around 5 mm. The sand is very loose in this area and as said earlier this could play a

significant role in the long term accuracy of those spikes.

17

GNSS surveys

Carramar

Figure 1: View of the Network for Carramar. Taken from SPECTRUM processing software

(not to scale)

Table 9: Comparison of the PSM Coordinates from CSD editor (Landgate, assessed august

2009) and from the GPS survey (fully constrained solution).

Comparison of PSM coordinates Carramar

Method PSM Easting Northing ∆Easting ∆Northing

CSD editor PSM West 384603.7180 6491088.8700 0.0110 -0.0320

Static GPS Survey PSM West 384603.7290 6491088.8380

CSD editor PSM East 385698.5860 6491680.6720 0.0220 0.0270

Static GPS Survey PSM East 385698.6080 6491680.6990

18

Munster

Figure 2: View of the Network for Munster. Taken from SPECTRUM processing software

(not to scale)



Comparison of PSM coordinates Munster


CSD editor PSM North 385230.8820 6444326.0530 0.0210 0.0120

Static GPS Surey PSM North 385230.8610 6444326.0410

CSD editor PSM South 385373.6530 6444140.4190 0.0200 0.0150

Static GPS Surey PSM South 385373.6330 6444140.4040

19

Aveley

Figure 3: View of the Network for Carramar. Taken from SPECTRUM processing software

(not to scale)



Comparison of PSM coordinates Aveley


CSD editor PSM South 403718.7174 6483021.6234 -0.0136 -0.0546

Static GPS Survey PSM South 403718.7310 6483021.6780

CSD editor PSM North 403783.5839 6483638.1734 -0.0181 -0.0526

20

Static GPS Survey PSM North 403783.6020 6483638.2260

Secret Harbour

Figure 4: View of the Network for Secret Harbour. Taken from SPECTRUM processing

software (not to scale)



Comparison of PSM coordinates Secret Harbour


CSD editor PSM South 384278.9470 6412887.6110 -0.0060 -0.0150

Static GPS Survey PSM South 384278.9410 6412887.5960

21

CSD editor PSM North 383910.3290 6414845.3940 -0.0370 -0.0010

Static GPS Survey PSM North 383910.2920 6414845.3930

The results of the GNSS survey were consistent. For each area the swing in Nothing or

easting were similar for the two PSMs observed. Carramar was the only SSA where the

swing was not the same for the two PSMs. The PSM west was further south by 32 mm than

what is stated on the CSD editor while the eastern PSM was 27 mm further north than stated

(Table 9). Munster had a general west nad south swing of about 20 mm and 13 mm

respectively (Table 10). Aveley’s PCMs had the biggest swing of all the PSMs observed. The

PSMs in Aveley were about 53 mm to the north and about 15 mm to the east of where they

should be (table 11). The old area and new area of secret harbour had a general swing to the

west and south but not of the same magnitude. The biggest swing was in the new area with a

swing to the east of about 37 mm.

22

Conclusion

Special surveys areas regulation have been put in place eight years ago to simplified the

subdivision process and the reestablishment of the boundaries corners in the future. Based on

the data obtained, it was seen that although earlier SSAs met this goal the some recently

established SSAs have not proved great although they meant the required standard set in the

‘survey practice guidelines for subdivisions within special survey areas’. Aveley was a good

example of what an SSA should look like. Although the marks coordinate where found to be

deferring from the CSD editor coordinates, it can be concluded that most of the error obtained

was due to incorrect SSMs initial coordinates as the survey observation achieved a Class A

standard. The SSMs should be checked against their reference marks and their coordinates

should be checked by an independent survey to prove this statement. Nevertheless, Aveley

had a good number of survey marks (0.8 marks per block), good accuracy (2 or 3 mm for

permanent survey marks) and a good placement of surveys marks (longevity tested if new

bitumen was put in). The secret Harbour areas (old and New) had a similar quality of work

probably because it was done by the same survey firm. On the other hand, Munster, a

recently established SSA (2008), was of concern with gross errors in angles and distance

measurement. Landgate should be contacted regarding this subdivision because there might

be a new lodgement for this SSA that is not yet available to us or in the worst case scenario

the actual marking in the field do not agree with the information given on the deposited plan.

If such is the case, then according the Licensed Surveyor act 1909; the Surveyor General, and

any other person appointed by the Governor to approve plans, may by notice in writing call

on :

(a) any licensed surveyor holding a practising certificate to correct at his own

expense within a time specified in that notice any error made by him in an

authorised survey; or

(b) any person who is or was a licensed surveyor (the person at fault) to pay the

cost of correction by a licensed surveyor —

(i) holding a practising certificate; and

23

(ii) instructed by the Surveyor General or the other person appointed by

the Governor, as the case requires,

Therefore, an error in the plan could cost the surveying company dearly. The reputation of

the surveying company will also be clearly affected. In this report, the SSAs statistic did not

take into consideration the surveying companies, but there is without doubt a correlation

between the rating of SSAs and surveying companies. This accentuates the need for

surveyors to follow good surveying practices that are consistent throughout the industry.

Because most businesses evaluate their options on a benefit-cost analysis, some businesses

might be tempted to cut corners when doing a subdivision and do the minimum required b y

the regulations. Those businesses will clearly have a competitive advantage on their more

‘ethical’ competitors. If that behaviour becomes a common habit, termed ‘wickedness’

(Snow, 2009), then there will be a push for other companies to cut corners too in order to

compete. In the long term the whole idea behind SSAs could be jeopardise. This dilemma

highlights the importance of the SSI code of ethics, essentially a watchdog that ensures that

the industry has a high moral standard and quality of work. Maintaining the quality and

accuracy of a surveying project is also the task of the Survey Board of Western Australia and

of the inspecting surveyors at Landgate.

Recommendation for the SSAs regulations:

- A minimum mark density should be introduced - currently the regulation states that

any lot corner should be within more than 100 m of a survey mark- however if that

mark is on the other side of the road than we could end up with a lot corner with the

closest mark at almost 200m away (Appendix B).

- Marks that end up under major civil engineering structures should not be acceptable

and not be recorded on the deposited plan. Most structures location, such as path,

roads and retaining walls, are available to the surveyor and he should locate his

marking clear of those structures if possible. If not possible he should defer some of

his marking after the structures are built. For instance, of the IPs spike in Munster are

under the path or the road where no one can access them.

- There should be a certain percentage of the making referred as permanent (i.e. survey

marks that will be there in the long term).

24

- In the mining industry the phrase on everyone lips is ‘do it safe or don’t do it’ because

safety is there major concern. In the cadastral surveying industry it should be ‘do it

right or don’t do it’. It only takes take a few minutes to put a mark on line while a

surveyor is setup on that line. That mark could safe a surveyor a considerable amount

of time and money in the future.

25

References

Inter-Governmental committee on Surveying and Mapping Standards and Practices for

Control surveys (SP1) Version 1.7 (2007) ICSM Publication No. 1

Licensed Surveyors Licensing Board of Western Australia (2006) Survey Practice Guidelines

for Subdivisions within Special Survey Areas. Internal publication. Western Australia

Licensed surveyor act 1909 (1909) Western Australian Consolidated Acts. Western Australia

Licensed Surveyors (Guidance of Surveyors) Regulations 1961(1961) Western Australian

Consolidated Regulations. Western Australia

Snow, T. (2009). Survey Law, Ethics and Practice 481 lecture notes. Curtin University of

Technology. Western Australia

Traffic Management for Work on Road, Code of Practice (2009) Main Road Western

Australia.

26

27

Final Report

Documents

gnss surveys

year project

engineering surveys

total station surveys

university equipment

gnss component

gnss receivers

survey store