Rock Bolting Development Site

Item details


Name of item:	Rock Bolting Development Site
Other name/s:	Cooma Back Creek, Scientific Services Division, SMHEA
Type of item:	Built
Group/Collection:	Scientific Facilities
Category:	Other - Scientific Facilities
Location:	Lat: -36.24109 Long: 149.116835
Primary address:	Sharp Street, Cooma, NSW 2630
Local govt. area:	Snowy Monaro Regional
Local Aboriginal Land Council:	Merrimans

Property description

Lot/Volume Code	Lot/Volume Number	Section Number	Plan/Folio Code	Plan/Folio Number
PART LOT	3		DP	704165

Boundary:

The lot of land in which the Rock Bolting Development Site falls is Crown Land administered by NSW Government. It is of approximately 1042 hectares, being Lot 3 of Deposited Plan 704165 and was registered on 30 October 1984. It was later gazetted by the NSW Parliament for environmental protection as a public place. The Rock Bolting Development Site itself forms only a small portion of the total area of the Lot, covering the right bank of what is generally known as Lambie Gorge, through which Cooma Back Creek flows.

All addresses

Street Address	Suburb/town	LGA	Parish	County	Type
Sharp Street	Cooma	Snowy Monaro Regional			Primary Address

Owner/s

Organisation Name	Owner Category	Date Ownership Updated
Department of Trade & Investment --Crown Lands	State Government

Statement of significance:


	The Rock Bolting Development Site is of state heritage significance as the location of field testing of a pioneering Australian methodology for the permanent support of underground excavations in hard rock, using patterned rock bolting. The practice made tunneling safer, faster, and less expensive than earlier methods and quickly spread worldwide; it continues with little change today. The drilled holes and remnant rock bolts exposed in the rock faces of Lambie Gorge are evidence of where 'pull-out' tests were undertaken to prove a rock-bolt anchorage that was as strong as the bolt itself. Rock bolts had been used in coal mines from 1912 primarily to attach loose slabs to more stable rock layers, and their use began in hard rock in Sweden in 1939. However, the approach was empirical without theoretical guidance or the backing of laboratory experiments. The methodology for the permanent support of underground excavations in hard rock was developed by the Snowy Mountains Hydro-Electric Authority between the mid 1950s and the early 1960s, through design research, coupled with testing, measurement and trials.
	Date significance updated: 11 Jul 16
	Note: The State Heritage Inventory provides information about heritage items listed by local and State government agencies. The State Heritage Inventory is continually being updated by local and State agencies as new information becomes available. Read the Department of Premier and Cabinet copyright and disclaimer.

Description


Designer/Maker:	Snowy Mountains Hydro-Electric Authority Personnel
Builder/Maker:	Snowy Mountains Hydro-Electric Authority personnel
Construction years:	1956-1962
Physical description:	The Rock Bolting Development Site is located on a bank of Lambie Gorge through which Cooma Back Creek flows. The site is accessed from Sharp Street (Snowy Mountains Highway) in central Cooma, near the Park commemorating the 'Southern Cloud' airliner, by a Public Reserve pathway along the bank of the Cooma Back Creek, via the Cooma Agricultural and Pastoral Society Showgrounds and the Cooma Bowling Club. The site comprises a natural rock face into which holes have been drilled. Bolts of various designs project from some of these holes. Blasted fallen rock in front of the main test area is evidence of a succession of test faces within the span of usage of the test site. There are two main areas where the rock bolting experimental tests were conducted. A succession of tests were conducted in the area at the downstream end of the gorge.
Physical condition and/or Archaeological potential:	The holes and bolts are in excellent condition as they have not been disturbed. The broken rock and bolts from previous experiments are still in place.
	Date condition updated:04 Dec 13
Modifications and dates:	A succession of test faces is evident by the blasted fallen rock in front of the main test area. This was undertaken within the span of the testing at the site.


Current use:	Crown land dedicated for environmental protection
Former use:	Aboriginal camping area; dairy paddock; scientific experiments

History

Historical notes:

Lambie Gorge contains evidence of the occupation by the Aboriginal people up until the time of European settlement in the 1830s. The Aboriginal people's descendants of the Ngarigo Nation today, through their Elders, want to use this Lot to share their own heritage and have spent an Environmental Trust grant to construct a walking path and a lookout in 2004-5. The artefacts found within the Lot indicate that it was frequented by all family members for camping. There are, however, no monuments, no artworks and no songs associated with the place. As a result of an archaeological inspection in 2002 by the NSW National Parks and Wildlife Service, it was concluded also that there were no confirmed grinding grooves in the watercourse. The recognition of the Rock Bolting Development Site as an engineering heritage item had been accepted in a true partnership with the Ngarigo Nation people as an expression of reconciliation on this land. It is evidence by the tourist brochure produced in 2005 with the above grant, 'Lambie Gorge Walking Track'. This was a project of the Cooma Reconciliation Committee. Refer to the attached two sheets.

From the mid 1950s through to the early 1960s the Snowy Mountains Hydro-Electric Authority (SMHEA) developed a method to prevent large tunnels and underground caverns from collapse through the use of patterned rock bolting, with bolt placement designed according to the rock structure.
The methodology was shared internationally and was adopted worldwide; it and the hardware remain essentially the same as those developed by the Snowy Mountains Authority.
The Cooma Rock Bolting Development Site was within the property of the Authority's Scientific Services Laboratory where laboratory testing of the rock bolting methodology was performed and developed. The site in Lambie Gorge is where ‘pull-out’ tests were undertaken to prove a rock-bolt anchorage that was as strong as the bolt itself. The site, which is accessible to the public, displays drilled holes and remnant rock bolts in the rock faces where the testing was performed.

Many people were engaged within several engineering laboratories of the SMHEA, the civil design office and at the underground construction sites themselves for the massive Snowy Mountains Hydro-Electric Scheme. In addition, efficient installation techniques were devised to maximise the effectiveness of rock bolting for all its benefits to a project. The work in the gorge on successive occasions led to the approval for the commercial supply for rock bolting components under a series of underground construction contracts for the Scheme.

Permanency of the rock bolting design was crucial to its full development and acceptance. This came from sealing the whole bolt system and by transferring the tensile force from bolts positioned in a pattern across the full span into a lasting compression and locking force. This aspect of the development was proven in the laboratories and refined under contract conditions at the construction sites.

The Cooma Rock Bolting Development Site represents a suitable location for recognising the development of pattern rock-bolting and its contribution to the engineering discipline of rock mechanics. It was a SMHEA team effort led by engineering management that delivered very significant achievements in tunnelling speeds that regularly set new world records together with very large savings in construction costs and improved construction worker safety; it also engendered enthusiasm and pride in the project work of the Authority.

The Rock Bolting Developmnent Site was declared a National Engineering Heritage Landmark by Engineers Australia on 18 October 2009 when a plaque and interpretive sign were unveiled at the site. The Landmark is the highest level of heritage recognition accorded by Engineers Australia. The event was timed to coincide with the celebration of the 60th anniversary of the Snowy Mountains Scheme.

Rock Bolting - the detailed description and justification
Rock bolting in hard rock involves drilling a hole into sound rock at the excavated face (commonly between 1.50m and 6.00m deep depending on the conditions and rock structure), with a diameter to suit an expansion unit anchor - often about 45 mm diameter. A steel rod - the bolt, is then inserted with an expansion unit at the embedded end. At its exposed end the bolt is threaded and fitted with a nut under which is a small steel plate that bears on a conical rubber seal to seal the hole entrance when grouting is taking place. Screwing the nut down onto the plate and thus the rock surface, causes the embedded expansion unit to expand and anchor the bolt in the hole, this in turn allows a predetermined tension to be applied to the bolt. The aim is to have the anchor hold the full elastic tensile strength of the bolt. The hole surrounding the bolt is then filled with non-shrinking grout in a way that displaces the air. When the grout sets, it forms a permanent bond between the bolt and the surrounding rock.

When the bolt is tensioned by the nut against the plate at the surface, the compressive and transverse forces lock the layer of rock against further movement. The forces induced by tensioning the bolts create a pre-stressed membrane across the surface of the excavated rock face which neutralises the internal forces in the rock.

The use of non-shrinking grout enables the bolt components to transfer load to the adjacent rock over its whole length, as well as providing an inhibiting environment against corrosion. The formula for the non-shrinking grout which exactly compensates for the shrinkage of normal grout, was in itself, an inspired innovation by engineers of the SMHEA Scientific Services Laboratories.

Pull-out tests were conducted at the Rock Bolting Development Site to obtain data that would show the anchorage strength compared to the strength of the bolt. A dozen or so rock bolts at the site were used to prove the effectiveness of the grouting and the strength of the anchorage.

Many other steps were taken in the scientific laboratories of SMHEA to make an integrated, fully developed rock bolt reinforcement system that remained as a permanent structure, protected from corrosion.

In most instances rock bolting can replace the need for surface steel supports and the accompanying over-excavation to accommodate them, and it can avoid the need for separate concrete support of underground excavations.

It has been estimated that rock bolting reduced the steel required for support to one eighth of that required using conventional methods. It also saved the cost of over-excavation (and removal of the additional excavated rock) to accommodate supports and/or lining. Contractual pricing at the time showed a 45% increase in cost for fully concrete lined tunnels where light steel external supports were used instead of rock bolts. While much time and labour were saved by these excavation benefits, they also enhanced tunnelling safety. It was also an additional time-saver in that the rock bolts needed to be installed immediately after each advance of the tunnel excavation and simultaneously with the next face drilling and face exposure, before the laying of explosive charges in these holes.

Location of the Rock Bolting Development Site
The Rock Bolting Development Site on Cooma Back Creek in Lambie Gorge was deliberately chosen for geological reasons because the mineralogical composition of the Cooma gneiss was similar to the granite in the known construction sites in the Snowy Mountains. These sites were for the underground hydro-electric power stations, Tumut 1 and Tumut 2 and their associated tunnels.

The other factor giving rise to the usefulness of the Rock Bolting Development Site was that it was near the Engineering Laboratories of Scientific Services Division of SMHEA. These laboratories were where the testing personnel worked with their testing apparatus, both fixed and portable. All this land was then under the ownership of SMHEA and had been in use for six years in connection with other experimental work associated with the laboratories. The original SMHEA building for Engineering Materials and the storage buildings still stand (at 2016). The image shows the relationship of the Rock Bolting Development Site (near the rock abutment on right) to the laboratory seen in the centre background. In the years of testing activity a foot bridge at the height of the flood plain allowed for the crossing of Cooma Back Creek to the Rock Bolting Development Site from the laboratories.

Historic themes

Australian theme (abbrev)	New South Wales theme	Local theme
1. Environment-Tracing the evolution of a continent's special environments	Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures.	Modification of terrain-
1. Environment-Tracing the evolution of a continent's special environments	Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures.	Environments important to Aboriginal traditional and spiritual life-
1. Environment-Tracing the evolution of a continent's special environments	Environment - naturally evolved-Activities associated with the physical surroundings that support human life and influence or shape human cultures.	Changing the environment-
2. Peopling-Peopling the continent	Aboriginal cultures and interactions with other cultures-Activities associated with maintaining, developing, experiencing and remembering Aboriginal cultural identities and practices, past and present.	Aboriginal Culture-
2. Peopling-Peopling the continent	Migration-Activities and processes associated with the resettling of people from one place to another (international, interstate, intrastate) and the impacts of such movements	Settling in rural and remote areas-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Developing local, regional and national economies-National Theme 3
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Unseen but Present-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Landscapes of cultural and natural interaction-
3. Economy-Developing local, regional and national economies	Environment - cultural landscape-Activities associated with the interactions between humans, human societies and the shaping of their physical surroundings	Landscapes of institutions - productive and ornamental-
3. Economy-Developing local, regional and national economies	Events-Activities and processes that mark the consequences of natural and cultural occurences	Developing national landmarks-
3. Economy-Developing local, regional and national economies	Exploration-Activities associated with making places previously unknown to a cultural group known to them.	Exploring and surveying for the Crown-
3. Economy-Developing local, regional and national economies	Technology-Activities and processes associated with the knowledge or use of mechanical arts and applied sciences	Engineering for hydro-electricity generation in Australia-
3. Economy-Developing local, regional and national economies	Technology-Activities and processes associated with the knowledge or use of mechanical arts and applied sciences	Developing hydro-electric power in Australia-
3. Economy-Developing local, regional and national economies	Technology-Activities and processes associated with the knowledge or use of mechanical arts and applied sciences	Technologies for rock bolting practice and rock mechanics study-
4. Settlement-Building settlements, towns and cities	Accommodation-Activities associated with the provision of accommodation, and particular types of accommodation – does not include architectural styles – use the theme of Creative Endeavour for such activities.	Building settlements, towns and cities-National Theme 4
4. Settlement-Building settlements, towns and cities	Land tenure-Activities and processes for identifying forms of ownership and occupancy of land and water, both Aboriginal and non-Aboriginal	Administering and alienating Crown lands-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Developing and operating manorial villages-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Creating landmark structures and places in regional settings-
4. Settlement-Building settlements, towns and cities	Towns, suburbs and villages-Activities associated with creating, planning and managing urban functions, landscapes and lifestyles in towns, suburbs and villages	Developing the social life of a rural community-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Being a part of a trades guild-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Workers organising workers-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Working independently on the land-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Providing migrant labour-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Working complex machinery and technologies-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Working on the land-
5. Working-Working	Labour-Activities associated with work practises and organised and unorganised labour	Working in industrial complexes-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	State government-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Federal Government-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - providing electricity-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - administration of land-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - public land administration-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - building and operating public infrastructure-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - conserving cultural and natural heritage-
7. Governing-Governing	Government and Administration-Activities associated with the governance of local areas, regions, the State and the nation, and the administration of public programs - includes both principled and corrupt activities.	Developing roles for government - public water supply-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Developing cultural institutions and ways of life-National Theme 8
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Applying architectural design to utlilitarian structures-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Adaptation of overseas design for local use-

Assessment of significance


SHR Criteria a) [Historical significance]	The Rock Bolting Development site is of state heritage significance for its role in the history and development of the applied science of rock mechanics in NSW, Australia and internationally. It was the site at which a quantum leap in knowledge, methods and techniques of rock excavation and tunnelling were developed in the 1950s and 1960s. The new methodology led to a significant reduction in the cost of rock excavation and tunnelling, vast improvements in safety of workers and increased speed at which rock tunnelling projects could be completed.
SHR Criteria b) [Associative significance]	The Rock Bolting Development site is of state heritage significance for its strong association with the widely acclaimed Snowy Mountains Hydro-Electric Authority and its expert professional staff. The new methodology had significant associations with major tunnelling contractors.
SHR Criteria c) [Aesthetic significance]	The Rock Bolting Development site is of state significance for its aesthetic and technical values in NSW. The aesthetically distinctive rock face and scattered remnant shards are a strong visual representation of the creative and lateral thinking leading to the ground-breaking research in the science of rock mechanics.
SHR Criteria d) [Social significance]	Regarded as the most significant engineering development made on the Snowy Scheme, the Rock Bolting Development site is of state significance as it is held in high esteem by the engineering fraternity in NSW and Australia.
SHR Criteria e) [Research potential]	The Rock Bolting Development site, with its still evident bolts and bore sites and the rock shards dislodged during experiments, is of state heritage significance for its potential to demonstrate the process of developing the rock bolting techniques in NSW. The site can also demonstrate the precedence of the work of the Snowy Mountains Hydro-Electric Authority and its impact in the engineering fraternity worldwide.
SHR Criteria f) [Rarity]	The Rock Bolting Development site is of state heritage significance as it is the only site where such activity was undertaken in Australia.
SHR Criteria g) [Representativeness]	The Rock Bolting Development site is of state heritage significance as a representative location for engineering experimentation that contributed significantly to the development of engineering science in NSW, Australia and the world.
Integrity/Intactness:	The site retains many of the bolts and drilled holes of the original field tests.
Assessment criteria:	Items are assessed against the State Heritage Register (SHR) Criteria to determine the level of significance. Refer to the Listings below for the level of statutory protection.

Procedures /Exemptions

Section of act	Description	Title	Comments	Action date
57(2)	Exemption to allow work	Standard Exemptions	HERITAGE ACT 1977 ORDER UNDER SECTION 57(2) TO GRANT STANDARD EXEMPTIONS FROM APPROVAL I, Penny Sharpe, the Minister for Heritage, on the recommendation of the Heritage Council of New South Wales and under section 57(2) of the Heritage Act 1977: revoke the order made on 2 June 2022 and published in the Government Gazette Number 262 of 17 June 2022; and grant an exemption from section 57(1) of the Act in respect of the engaging in or carrying out the class of activities described in clause 2 Schedule A in such circumstances specified by the relevant standards in clause 2 Schedule A and General Conditions in clause 3 Schedule A. This Order takes effect on the date it is published in the NSW Government Gazette. Dated this 29th day of October 2025 The Hon Penny Sharpe MLC Minister for Heritage For more information on standard exemptions click on the link below.	Nov 7 2025

Standard exemptions for engaging in or carrying out activities / works otherwise prohibited by section 57(1) of the Heritage Act 1977

Listings

Heritage Listing	Listing Title	Listing Number	Gazette Date	Gazette Number	Gazette Page
Heritage Act - State Heritage Register		01984	23 Dec 16	120	3736

References, internet links & images

Type	Author	Year	Title
Written	DG Moye, Head of Engineering, Geology Branch	1956	SMHEA memorandum 27/8/1956: identifying the site for rock bolting experiments
Written	DG Moye		Daniel George Moye: Personal Papers MS5861
Written	EB Pender, AD Hosking, RH Mattner	1963	Grouted Rock Bolts for Permanent Reinforcement of Major Underground Works
Written	Engineers Australia, Monaro Group	2006	Lambie Gorge Rock Bolting Heritage Site: Management Plan Outline
Written	ET Brown	1999	Rock Mechanics and the Snowy Scheme
Written	Professor TJD Leech		Professor TJD Leech: personal papers MS 4837
Written	RT Brodie & AD Hosking	1962	SMHEA Engineering Construction Materials Report No. SM 1309. May 1962. Field Pull out Tests on Strengthened Bayliss-Jones-Bayliss quick set rock bolt anchorages (Para 3.2).
Written	Snowy Mountains Hydro-Electric Authority		Snowy Mountains Hydro-Electric Authority: papers
Written	WB Mills	2009	The Snowy Men Behind Tunnel Rock Bolting
Written	WB Mills	2006	Index of Reference Documents: Engineering Heritage of National Significance -- Rock Bolting & Speciality of Rock Mechanics, Rock Bolting Development Site
Written	WB Mills	2006	Personnel credited with substantially contributing to the Engineering of the Rock Bolting Technology and the engineering discipline of rock mechanics

Note: internet links may be to web pages, documents or images.

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Data source


The information for this entry comes from the following source:
Name:	Heritage NSW
Database number:	5060277
File number:	H09/00070;13/03128; EF11/03128

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