NSW Survey Marks

Property in NSW is underpinned by land boundaries. Survey plans have defined each parcel of land in the state since freehold land was first granted by the Crown. When you stitch every parcel of land together to see the fabric of boundaries that makes up the state, this is called the cadastre.

Registered surveyors in NSW are custodians of the cadastre. We are responsible for ensuring that any updates or changes to the cadastre are legally and mathematically correct. This means that any registered survey must connect to existing boundaries and prove that the survey is valid, does not create overlapping lots, or gaps between lots, and places enough marks to allow future surveyors to connect to the plan.

To achieve this, surveyors must durably mark the boundaries of the land. In addition to marking boundaries, surveyors must also place, or connect to, other marks that can be used to recreate the survey. Other than boundary marks, there are a range of different kinds of marks used to recover boundaries if boundary corners themselves are gone.

Boundary marks

Boundary corners have been marked using some form of boundary peg for the entire history of New South Wales. Where it isn’t possible to place a peg, the boundary corner can be marked with other forms of mark. When boundary lines are not fenced, marks are to be placed along the boundary line, to enable the line to be fenced.

Boundary marks are most commonly pegs.

Where a peg is unable to be placed, boundary corners may be marked using standard marks as set out in the Surveying and Spatial Information Regulation in force at the time.

Reference Marks

All plans of survey must place reference marks. The number of reference marks required on any plan is dependent on the number of lots, the length of road frontage, the length of boundary lines, and the terrain. Reference marks are shown on a deposited plan (DP) with a bearing and distance. The bearing is the angle from north – similar to a compass bearing, although magnetic meridian is not typically used for survey plans in most cases. Distances are shown in metres. Reference marks show the bearing and distance from the mark to the corner. Other states in Australia reverse this convention.

To understand how reference marks are used to recover boundary lines, consider the simple example below:

A diagram showing rectangles in blue with lines vertically down from the bottom corners.

Geometry of Reference Marks

In this example, the boundaries of the land that has been surveyed are shown in dark blue. Two reference marks have been placed, located to the bottom of the site, represented by red lines. The bearings and distances from the reference marks to the boundary corner are known. If the boundary marks are removed – for example in order to build a fence – a surveyor can use the geometry of the reference marks and boundaries to re-establish where the boundary corners are.

Permanent Marks

NSW maintains a database of permanent survey marks within the state. These marks are generally more durable than reference marks, and have coordinates (latitude and longitude, or easting and northing) and height above sea level (in most cases). Each permanent mark is individually numbered, to enable searching within the database.

Each deposited plan (DP) of survey must connect to a minimum number of permanent survey marks, depending on the number of lots, the size of the survey, and the zone (urban or rural). These marks tie the cadastre together and assist in linking boundaries to physical and digital features, from railways and roads to aerial imagery and Google maps.

Types of common marks

Boundary pegs

Where possible, boundary corners should be marked with boundary pegs. Historically, boundary pegs are made of timber. In NSW, different shaped pegs have different purposes. For urban land, pegs are nominally 75mm x 50mm, and 350mm long. For rural land, pegs are nominally 75mm square, and 450mm long. The centre of the peg is meant to represent the actual corner of the boundary. If the peg can’t be centred on the boundary corner, a nail or other mark should be placed in the peg at the boundary corner. Typically, boundary pegs are painted white.

On an unfenced boundary, lockspits are required to be placed adjacent to pegs. A Lockspit is a trench, or line of packed stones, not less than 1 metre long. The trench or line of stones is to be placed in the direction of any boundary line. The trench is to be 200mm wide, 150mm deep, and commence 300mm from the peg.

In more recent times, polypropylene pegs have been introduced. These pegs have the same dimensions as the timber pegs. The advantages of poly pegs are:

  • Poly pegs do not rot, and are not susceptible to termites,
  • Poly pegs are lighter to carry,
  • Poly pegs generally do not split when placed,
  • Poly pegs remain white over time.

Poly pegs do cost more than timber pegs, however many surveyors are embracing this technology for the benefits outlined above.

Image of a white rectangular boundary peg with a tall timber stake behind it. The stake has the words

An urban poly peg with indicator stake.

A white timber peg standing in tall grass. An indicator stake stands to the left of the peg with the words

A rural timber peg, used on a boundary as a line peg.

A White poly peg in a grassed area. A tall timber stake stands to the left of the peg. Red flagging tape is tied to the stake.

A rural poly peg.

A white poly peg visible at the intersection of two lines of rocks (A rock lockspit).

An example of a rock lockspit with poly boundary peg.

Image of an old timber survey peg with no paint. A broad arrow is carved into the side of the peg. A small nail is in the top of the peg.

A rural timber boundary peg, approximately 15 years old.

A very old and decayed timber survey peg, standing in red, sandy soil.

A very old rural timber boundary peg, approximately 40 years old.

An area of ground, scraped clear of grass. A square shape has been scratched in the dirt, highlighting the profile of where a peg stood, now rotted away.

When timber pegs rot almost completely away, they can still be found.

A boundary peg, split in two, lying on red coloured soil.

One disadvantage of timber pegs is the probability of them splitting when being placed.

Drill Hole and Wing

Where the boundary corner falls on rock or concrete, the corner can be marked with a drill hole, with a triangular wing pointed towards it. Older forms of this mark included more than one wing. A drill hole and wing can also be used as a reference mark.

Image of concrete showing a chiseled triangle shape. Above the apex of the triangle is a drill hole.

A modern drill hole and wing.

An image of concrete with a broad arrow chiseled into it. Above the point of the broad arrow is a drill hole.

An older style drill hole, with broad arrow.

Metal spike (rod) or galvanised pipe

A metal spike or galvanised pipe, at least 300mm long may be used to mark a boundary corner. Metal spikes must be at least 20mm diameter, and galvanised pipes must have internal diameter of at least 20mm with wall thickness of at least 2mm. When marking a boundary corner, these marks are placed vertically in the ground with the top of the mark being flush with the surface. Where these marks are used as a reference mark, the top of the mark is to be placed at least 80mm below the surface.

Image of a round, galvanised steel rod lying beside a cordless drill with large bit.

Compass Consulting Surveyors often use galvanised steel rods, 20mm diameter, 400mm long.

Image of the top of a piece of galvanised iron pipe in the ground. Only the top of the pipe is visible as a circle in the dirt. A hand is pointing to the location of the pipe.

A Galvanised Iron Pipe in place.

Image showing a piece of pipe standing in the ground at an angle.

This galvanised iron pipe was found disturbed, at an angle and projecting from the ground.

Survey Reference Trees

Under the Surveying and Spatial Information Regulation, 2017, a non-corrodible nail and wing in a tree is a valid form of reference mark. This form of reference mark is rarely used today. While trees can last for many years, they are vulnerable to termites, bushfires, and anthropological issues – machinery operators! Older surveys used trees as a primary reference mark. The passing of time means that finding reference trees is not as common as it was in years past, making the task of re-establishing boundaries significantly more difficult.

I have covered many examples of survey trees in my blog https://compasscs.com.au/survey-reference-trees/.

Hand-drawn Diagram showing blazed tree

Extract from 1886 Regulations showing form of reference trees.

Hand drawn diagram

Extract from Surveying Regulations 1872 showing form for trees on or near boundary lines.

Image of an Australian box tree with a scar in the trunk. In the scar is a broad arrow, with the letters

A survey reference tree placed for a road survey in western NSW, approximately 50 years old.

Image of a tree with a scar in the trunk. Letters have been carved into the timber in the scar.

A reference tree on the banks of the Darling River, western NSW.

Historical reference marks

In the late 1800s and early 1900s, certain surveys were required to place “permanent marks”. These differ from what we call permanent marks today. The original permanent marks were typically of three styles:

  • Glass bottles, filled with a concrete and ash plug, buried upright in the ground (no longer approved marks),
  • Galvanised iron pipes (gas pipes) being 1 foot (~300mm) long, buried upright in the ground, and
  • Iron spikes (rods or bolts) being at least 1 foot (~300mm) long, buried upright in the ground.

It is quite rare to find bottle marks. They are difficult to locate, as they are generally buried quite deeply, and are not able to be detected using a metal detector.

The top of a glass bottle projects from dirt.

A “permanent mark” bottle, placed vertically, filled with a concrete-like mixture, buried below the ground. This bottle is located at Canbelego in western NSW.

A bottle-shaped piece of concrete. The glass bottle has been broken from around the concrete which was poured inside the bottle.

The plug of a bottle. This bottle was broken during the search for it.

Galvanised iron or iron rod style permanent marks are easier to find, with a metal detector. These marks are also commonly buried quite deeply.

Permanent Survey Marks

Modern permanent survey marks have a range of different forms. They are designed to be much more durable than boundary marks, and ideally more durable than the reference marks described above. It should be noted that a permanent survey mark can be shown on a plan as a reference mark, but does not have to be one.

Approved permanent marks are described in detail in the Surveyor General Direction No. 1. There are three basic forms of permanent survey marks:

  1. Permanent Marks

A permanent mark (PM) consists of a cast iron cover box over a mark installed in the ground. Each PM has a unique number. The mark under the cover box varies. In rural areas, the mark is often a star picket. An alternative is a FENO mark, with resin collar an stainless steel pin. In urban areas, permanent marks are usually a stainless steel pin set in concrete.

A cast iron box painted yellow is shown flush with ground level.

A Permanent Mark (PM) in place.

A square cast iron box painted yellow, with a round lid in the middle, opened.

A permanent mark box with a FENO mark in place.

  1. State Survey Marks

State Survey Marks (SSMs) are fixed into concrete or rock. Each SSM has a unique number. They are usually utilised in urban areas, being placed into kerbs or footpaths. There are two commonly used forms: Types 1 and 2, being brass plaques, and Type 15, being a stainless steel pin with collar.

A round brass plaque in concrete. The words State Survey Mark NSW are embossed around the edge of the mark. A flat plate has numbers stamped in to identify the unique mark.

A Type 2 State Survey Mark in concrete.

A round brass plaque fixed in rock.

A Type 2 SSM placed in rock.

A stainless steel disc with a raised pin in the centre. The disc has the words

A Type 15 SSM placed in concrete.

  1. Trigonometrical Stations

Trigonometrical Stations (Trig Stations) were originally designed to be observed via line of sight. They are usually located on high points, such as mountains or buildings. Each trig station has a unique number, and a name. I have written more about trig stations in my blog here: https://compasscs.com.au/trig-stations/

An old trigonometrical station, consisting of a cairn of rocks, a timber post standing in the middle, with metal vanes affixed to the post.

An old trigonometrical station. The actual mark is a brass plug in the ground. To access the mark, a surveyor is meant to unstack the cairn of rocks and remove the post, exposing the plug.

An old trig station, cairn of rocks with wooden post. Metal vanes are attached to the post.

An older trig in good condition.

A round shaft made of brass, projecting from dirt.

This is a plug for an old trig station, a brass plug set into bedrock with a concrete-like mix.

A white pillar, tapering smaller towards the top. A white post projects from the top of the pillar. Black vanes are attached to the post.

A modern style trig pillar. The mark for these pillars is located under the post and vanes.

A white pillar, tapering smaller at the top. On the flat top of the pillar is a surveying instrument.

A surveying total station mounted on a trig station.

Other Marks

There are a variety of other marks that have been used as survey monuments. These may include the corners of buildings or other structures, stainless steel tokens (pin/collar, similar to SSM type 15), concrete blocks (concrete block in the form of a truncated pyramid 400mm long, 150mm square at the lower end and 100mm square at the upper end with a galvanised nail or other suitable metal peg or plug not less than 80mm long inserted in the block) and many more.


The goal of placing a survey mark is to make it as durable as practicable, while being fit for purpose. Boundary marks are often less durable than reference marks, because it is assumed that boundaries will be fenced. On that note, it is worth requesting that when you construct a fence on a boundary marked by a surveyor, please remove the pegs and place the corner of the fences directly at the point where the peg was located. This will ensure that your property is delimited along the legal boundaries, reduce the potential for future arguments over the specific boundary location, and make it easier for future surveyors to redefine boundaries.

This article is not a comprehensive list of survey marks. For further information, As always, Compass Consulting Surveyors are happy to answer questions about surveying and survey marks. Please contact us through our website if you have any questions.

Eric Smith

Registered Surveyor