Data Purchase and Supply

Document No:  D12#434794
Revision:  4A
Date amended:  14-May-2015
The information below is intended to reflect the preferred practice of Main Roads Western Australia ("Main Roads"). Main Roads reserves the right to update this information at any time without notice. If you have any questions or comments please contact Haydn Bufton by e-mail or ph (08) 9323-4655.

To the extent permitted by law, Main Roads, its employees, agents, authors and contributors are not liable for any loss resulting from any action taken or reliance made by you on the information herein displayed.


Revision Register


Ed/Version Number Clause Number Description of Revision Date
ISSUE 1 ALL  Guideline Development 13/07/01 
ISSUE 2 2 & 2.1  Update Links For License Agreement & Metadata Statement 04/09/07
​ISSUE 3 ​ALL ​Content Clean up ​06-Feb-2013
​ISSUE 4 ​Header ​Document Number Changed ​16-Jun-2014
​ISSUE 4A​Header​Guideline Introduction Amended​14-May-2015

Table of Content


Main Roads is both a large user and producer of digital data. The majority of this information comes from internal contracts, but with escalating costs in the data capture and improved links to alternate data sources, greater use of information held by other government agencies is also being utilised.

Because of the diversity of the information being used, and with most data now being used in an electronic form, care should be taken to ensure that when data is purchased or supplied that documentation should accompany the data to assist in the Identification, Traceability and Quality Control of the digital data.


The supply of data can be either to internal or external parties.

The information detailed below applies to both categories, the exception being where digital information is supplied to an external party for non Main Roads work. In this case a License Agreement for the use of the data is also required with the signed agreement retained on file.

For further information on the use of licence agreements refer to the guidelines on Data Licensing and Copyright.

When supplying digital information the following steps must be addressed

2.1 Metadata Statement

A Metadata Statement shall be supplied with all digital data. If various types of data are being supplied each will be accompanied by an individual statement. This is to ensure that the end user understands the quality and the appropriateness of the data in meeting his requirements.

For further information on metadata refer to the guidelines on Metadata Requirements.

2.2 Data Format

Digital data supplied by Main Roads is only to be supplied in a standard Main Roads format. That is, under no circumstances is data output, from an existing Main Roads software package, be edited to allow input into a third party software package. The onus is on the third party to ensure compatibility with their system.

2.3 Transfer Medium

Except for supply by E-mail, all digital information shall be supplied by a secure medium.

Floppy Disks shall be placed in an anti static bag and then encased in a disk mail box.

CD-ROMs or Cartridge/Exabytes shall be encased in hard copy cover supplied with the disk or tape.

2.4 Readme.1st file

In addition to individual metadata statements for the digital data each "transfer medium" shall also contain a readme.1st file which will define the contents and the structure of the data on the medium. This will assist the end user to readily identify what is on the disk.

Although not desirable where a metadata statement does not exist, the readme.1st file may contain any available metadata for the digital data being supplied to assist the end use. Under no circumstances is digital information to be supplied without associated metadata.

Example of a readme.1st file

2.5 Label on Transfer Medium

Irrespective of the type of medium used, the medium shall be properly labelled to identify its contents. This shall include a description of the data, a reference to the readme.1st file on the medium and the date that the data was placed on the medium.

2.6 Transmittal Note

All digital or hard copy data supplied shall be accompanied by a Transmittal Note. This form gives an overview of what is being supplied i.e.: Is the data contained on CD-ROMs or some other medium.

In addition the note also contains a section requiring the recipient of the data to notify the supplier that the data has been received. In all circumstances the supply of any digital data shall be accompanied by a transmittal note. The only exception is where data is forwarded by e-mail.

Transmittal Note Proforma

2.7 E-mail

Care should be taken when sending large amounts of data. A number of e-mail systems have a restriction on the size of information that can be delivered. This is generally set at around two megabytes. You should check with the company receiving the data for any restrictions.

2.8 Cost of Data Supply

For information on charging (cost recovery) for the supply of digital information refer to the section on Charges under the guidelines dealing with  Data Licensing and Copyright.



3.1 Sourcing Existing Data

Main Roads currently maintains a wide range of land information datasets. These have been acquired and developed to meet specific contract requirements at that time. Because of the nature and format of these datasets they have generally been acquired in their entirety from external sources.

Generally when obtaining digital information from government agencies a cost of extraction fee is incurred (refer Cost of Purchase below). This fee is calculated on the time taken to extract the data from its native format to the requested format. As the majority of datasets held by agencies are stored on a state-wide basis, care should be taken when purchasing the information. For example, by requesting a subset of the full dataset, increased costs may be incurred due to the requirement to manipulate the data to extract this subset. It is often cheaper to purchase the full dataset.

In addition the requesting agency will generally be required to sign a licence agreement to use the data before it is supplied.

In the case where the full dataset has been purchased to maximise the use of the data a copy should be lodged with the Data Manager - Road and Traffic Engineering. This will then be placed on a data server for use by the whole of Main Roads.

When the requirement arises to purchase digital information, it is an important step to check if existing data covering the project requirement is available. Available Data is an index of land information datasets currently held by Main Roads.

Due to copyright laws under no circumstances can this information be supplied to an organisation that is not undertaking work for Main Roads. In this case the requesting organisation is required to source the data from the original data custodian.

If you require any of the information detailed in the index or wish to source the availability of alternate land information please contact Data Manager - Road and Traffic Engineering.

Alternatively the availability of Land Information can be sourced from Interrogator On-line .

3.2 Cost of Purchase

Digital or hard copy information purchased by any government agency from another attracts a cost of extraction fee. As part of the information exchange policy between government agencies this fee is 10% of the actual cost. Although this is a significantly reduced price, depending on the type of information purchased the cost could still be significant eg. cadastral information.

To minimise costs and to ensure non duplication of purchased data please refer to the index of existing data detailed above before purchasing new digital information.

3.3 Purchase of Data by Consultants

A major policy instigated by WALIS (through government agencies) and ratified by the Executive Policy Committee (EPC) is the ability of government consultants/contractors to obtain government information at government rates. All government agencies currently obtain information at the  discount rate of 10% of actual cost whereas private industry pays the full 100%. At the WALIS Council meeting of June 16th 1999 it was passed that


"The meeting agreed that the acceptable approaches were for the Consultant to supply a letter and or a standard WALIS data request form, both detailing that the data was required for a government agency or alternatively for the agency to request the data themselves and pass it to the Consultant. Either of these methods should be specified in the original contract drawn up with the Consultant."


This means that there is two ways for a contractor working on a Main Roads contract to obtain external information (eg; Cadastral, Geodetic, Photogrammetric or Environmental information from other agencies). Either to obtain the information through Main Roads or request the information directly from a particular agency.

To do the latter, a letter authorising the contractor to obtain the information is required from the Project Manager as well as a signed license agreement. This is then forwarded to the respective agency. It is important to note however that agencies have set formats that data can be supplied in. If the format is not compatible and the contractor is obtaining the data direct then it is his responsibility to ensure the compatibility of the supplied data with his systems.