Underlying Geologies and Settlement Patterns in the Greater Bendigo Region

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Underlying Geologies & Settlement Patterns in the Greater Bendigo Region: How can understanding historical settlement patterns inform strategic development for future growth?

By Peter Grant s3662983


Contents

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Introduction

Introduction

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Research

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How has the underlying geology influenced settlement in the greater Bendiog region?

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How has the discovery of gold influenced the settlement of the City of Bendigo?

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How can these patterns influence future development strategies?

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Conclusions

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References

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A model of Victorian decentralization away from Melbourne has been in discussion over several decades. The introduction of fast rail network would only increase this sentiment. By significantly reducing transport times, a fast rail network puts a number of existing regional towns well within a catchment of reasonable travel times to Melbourne for daily commuters. The decentralization model away from Melbourne has a range of benefits including reducing congestion and mitigating urban sprawl. However if a fast rail network is implemented and decentralization occurs, these regional centres will face development pressures which they could be unprepared for. There are many issues related to the continued roll out of Greenfield developments both on the outskirts of Melbourne and in the regions, and in preparation for decentralisation questions should be asked about greenfield developments and whether they are the best way moving forward. This research framing recognizes that in order to understand how the City of Bendigo could expand or grow in a future situation where fast rail is implemented, it is important to recognise the settlement patterns which have lead to the current settlement and how they came to be. The research seeks to understand the Bendigo Landscape through it’s geological history, in order to inform future developments strategies.


Research Loddon Mallee South Regional Growth Plan (2014)

Greater Bendigo Housing Strategy (2016)

(Victorian Government 2014)

The document focuses on the broad region of Loddon Mallee South, which comprises Greater Bendigo and surrounding LGAS. It identifies the importance of Bendigo as a regional centre and establishes it’s importance for the entire region. They project that Bendigo’s population to grow to 150,000 by 2041, and the Greater Bendigo Region to grow to around 200,000. The paper identifies key drivers of change in the region such as: • • • • •

The proximity to Melbourne and it’s strong transport links. The relative affordability in the housing market when compared to Melbourne. Changes in the employment and economic sector. Managing growth within a naturally hazardous landscape, particularly floodin and bushfires. Impacts of changing climate bringing more extreme heat and weather conditions.

The paper also highlights a series of challenges for the growth of the region in terms of important considerations which should be accounted for in allowing the expansion of existing settlements relevant to Greater Bendigo. These include: •

• •

• •

Managing growth as to not overwhelm the environmental and social factors which attract such growth initially. Adapting to the potential impacts of climate change. Managing growth in a way which protects the environmental and natural assets of the region. Maintaining the extent of the regions agricultural areas in regards to their economic importance. Managing the risk of hazards such as floods and bushfires.

Balance Victoria (2019)

(City of Greater Bendigo 2016)

This document is prepared by the Greater City of Bendigo and focuses on issues which need to be considered as the population of Bendigo increases. The document aims to improve housing mix and availability, and advocate for improved housing outcomes. The document identifies the negative impacts of urban sprawl both on the economy and environment. They describe Bendigo as a ‘City in a Forest’ – a reference to the rings of bushland which surround the city, highlighting the risks associated with flooding and bush fires as development is pushed outwards from the fringes of the city. They also cite the negative health impacts related to these kind of greenfield developments which dominate the market. Specifically, they make the point that creating housing developments at the urban fringes is ‘increasingly unsustainable’. Similarly, this document references the steady population increase estimating that by 2036 the Population for the City of Bendigo will be 156,000. The current growth plans allow Bendigo to at around 900 houses per year for around 20 years (Keeping in mind this paper was written in 2016).

(Piko, Taylor & Horne, 2019)

Balance Victoria reflects on past government made decisions and how they influence the distribution of settlement patterns in and around Melbourne. The fundamental colonial experience of buying, dividing and selling land is at the centre of this. The document highlights issues around centralisation or decentralisation and driving factors such as land use zoning and the distribution of transport networks. It is interesting to consider how policy can influence factors such as decentralisation indirectly. The centralisation of cities around the world is attributed to shifts in trade networks. A move away from industrial manufacturing, and a shift towards globalisation and a knowledge-based economy is key to this. For this reason, in most of regional Victoria populations are decreasing. In terms of modern policy levers, the paper lists regional rail infrastructure in Geelong, Ballarat and Bendigo as being key. It lists the commuter role these regional centres have. In the wake of the global covid-19 pandemic and the reliance of working from home, these rural cities could play an even more significant role in population growth. The paper highlights whether a regional fast rail proposal would serve as a commuter expansion for Melbourne, or if there would be any potential negative effects on the regional centres. The paper finishes by recommending that the process of decentralisation could only be successful as an integrated approach.

References: City of Greater Bendigo 2016, Greater Bendigo Housing Strategy, viewed 13 August 2021 <https://www.bendigo.vic.gov.au/sites/default/files/2016-09/ Adopted%20Greater%20Bendigo%20Housing%20Strategy.pdf> Victorian Government 2014, Loddon Mallee South Regional Growth Plan, viewed 13 August 2021, < https://www.planning.vic.gov.au/__data/assets/ pdf_file/0033/94668/Loddon-Mallee-South-Regional-Growth-Plan-May-2014. pdf> Piko, L., Taylor, E., & Horne, R. 2019, Balance Victoria: Prospects for decentralisation. Melbourne: Centre for Urban Research, RMIT University.

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How has the underlying geology influenced settlement in the Greater Bendigo Region? In order to understand how a regional city like Bendigo could expand in the future, it is imperative the research considers how the region came to be as it is. These investigations frame the project with a dynamic set of landscape relationships, which can help to guide future trajectories for generative design.

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What is the underlying Geology of the Bendigo Region? The underlying geology of the area can be simplified into three main categories; Sedimentary, Volcanic and Fluvial. These three different geologies are interrelated, but each influence the topography, hydrology, and ecology in different ways. While there are clear patterns in this map, it feels very flat.

What is the relationship between geology and landform?

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000 Victoria Digital Elevation Model https://services.land.vic.gov.au SpatialDatamart/dataSearchViewMetadata. html?anzlicId=ANZVI0803003582&extractionProviderId=1

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Landforms What is the relationship between geology and landform? There is a clear relationship between the underlying geologies and the topography of the landscape. This is related to and really informed by how each of the different geological typologies was formed. The maps on the adjacent page show the individual geologies, and unpack how they were formed.

How has geology influenced vegetation coverage?

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000 Victoria Digital Elevation Model https://services.land.vic.gov.au SpatialDatamart/dataSearchViewMetadata. html?anzlicId=ANZVI0803003582&extractionProviderId=1

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Sedimentary Rock Volcanic Rock Fluvial Deposits

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Sedimentary - Castlemaine Group

Volcanic - Harcourt Granidiorite

Fluvial - Shepparton Formation

The sedimentary rock is the oldest underlying geology in the area. It consists of quartz and sandstone, and was deposited around 500 Million years ago in a deep marine environment.

The Harcourt Granidiorite volcanic rock which is closest to Bendigo was deposited around 350 Million years ago. There are other smaller deposits which have occured more recently - within the last 50,000 years.

The Fluvial Shepparton formation is a large covering of alluvial deposits which occured around 23 Million years ago. The geology was produced when the large basin of water that covered the area drained to the north. The Shepparton formation area is much flatter than the other two geological typologies.

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Vegetation Coverage How has geology influenced vegetation coverage? Broadly, across the region there is a clear correlation between the underlying geologies and vegetation communities which grow at the surface. The combination of soil types and topography has created a number of distinct vegetation typologies which are closely related to these factors. Using masks, the maps on the adjacent page explore how vegetation types are represented in each of the different geologies which were explored on the previous page.

How have geology, land form influenced land use?

Data: Native Vegetation - Modelled 1750 Ecological Vegetation Classes https://discover.data.vic.gov.au/dataset/native-vegetation-modelled-1750ecological-vegetation-classes

Simplified Vegetation Communities Dense Bush & Forests

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Open Grassy Landscapes Alluvial & Waterway


Sedimentary - Castlemaine Group

Volcanic - Harcourt Granidiorite

Fluvial - Shepparton Formation

The sedimentary rock is characterised by some of the more dense EVCs. The Box Ironbark Forest and Sandstone Ridge Shrublands are the two most dominant, and are made up of a relatively dense canopy of Eucalyptus trees and other shrubs.

The Harcourt Granidiorite volcanic rock which is closest to Bendigo was deposited around 350 Million years ago. There are other smaller deposits which have occured more recently - within the last 50,000 years.

The vast flat plains of the fluvial deposits allow for a quite different set of conditions. The flat plains were mostly made up of grasslands with sparse tree coverage, across fertile soils which were prone to intermittent flooding.

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How has geology and landform influenced landuse? 0

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Geology and Hydrology

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Agricultural Landuse Waterways

This map shows the clear strong relationship between the hydrology and the fluvial Shepparton Deposits. As the topography starts to flatten out, the streams from the central mountains form allong the geological changes. It indicates the high amount of water which is available in the area, as well as the nutrients which would have been deposited over millions of years due to flooding.

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Fluvial Deposits

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000 Victoria Digital Elevation Model https://services.land.vic.gov.au SpatialDatamart/dataSearchViewMetadata. html?anzlicId=ANZVI0803003582&extractionProviderId=1

For the reasons previously mentioned, this northern area above Bendigo has been primarily used for agricultural purposes. The clear relationships between the geology, topography and these agricultural land uses really sets the scen for understanding what types of vegetation communities have been destroyed and which ones have remained primarily intact.

Data: Landsuse 2016 https://discover.data.vic.gov.au/dataset/victorian-land-use-informationsystem-2016-2017 Victoria Digital Elevation Model https://services.land.vic.gov.au SpatialDatamart/dataSearchViewMetadata. html?anzlicId=ANZVI0803003582&extractionProviderId=1


How have agricultural land use practices impacted vegetation communities? Here, the clear relationship between the underlying geology and subsequent agricultural land uses, and the distribution of remaining vegetation. It shows that agricultural land use has impacted vegetation types like more open grassy plains more negatively than dense bushland and forests.

What is the condition of this remaining vegetation?

Data: Native Vegetation - Modelled 2005 Ecological Vegetation Classes https://discover.data.vic.gov.au/dataset/native-vegetation-modelled-2005ecological-vegetation-classes-with-bioregional-conservati-wms

Simplified Vegetation Communities

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Dense Bush & Forests Open Grassy Landscapes Alluvial & Waterway

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What is the condition of the remnant vegetation? It is clear the impact of agricultural practices has removed large portions of vegetation, fragmented the once connected ecosystems, and degraded much of the retained remnant vegetation. Almost all the remaining vegetation is classed as at risk. The maps also show a break in the pattern within the boundary City of Bendigo, where virtually all the vegetation is gone. It will be important to not only consider these broad landscape processes, but also to zoom in to focus more closely on Bendigo. In order to understand how these patterns have been formed within the City Boundary, research into the specific history of the settlement is neccesary.

How was Bendigo settled initially?

Data: Native Vegetation - Modelled 2005 Ecological Vegetation Classes https://discover.data.vic.gov.au/dataset/native-vegetation-modelled-2005ecological-vegetation-classes-with-bioregional-conservati-wms

Simplified Vegetation Communities Dense Bush & Forests Open Grassy Landscapes Alluvial & Waterway

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Fluvial Soil & Vegetation Health

Sedimentary Soil & Vegetation Health

This map isolates the remnant vegetations in fluvial soil surrounding Bendigo. The mask shows the fluvial soil with no remnant vegetation as the satelite image. The map highlights just how much of the remnant vegeation around Bendigo is these types of fluvial soils have been exploited. Much of the remaining vegetation if very fragmented and classed as either endangered of depleted.

For the vegetation on sedimentary soil around Bendigo it is a totally different story. Much of the vegetation is still relatively intact. Although the much of the vegetation is classed as ‘depleted’, because of the large swathes of connected vegetation it is less at risk than the fragmented grasslands as previously mentioned.

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How has the discovery of gold influenced the settlement of City of Bendigo? With a zooming in, the question from the previous page; ‘How was Bendigo settled initially?’ reveals a much more poignant question related to the history of gold in Bendigo (as stated above). This question represents a shift in scale in the research, zooming into the City of Bendigo and seeking to understand still how geology has influenced the settlement patterns.

Where was gold first discovered in Bendgio? Gold was first discovered in Bendigo is attributed to two ladies - Mrs Kennedy and Mrs Farrell, the wives of two farmers. They came across the alluvial gold as they washed clothes on the river, which sparked the gold rush. The location of the discovery, as well as it being alluvial gold are significant in how the city of Bendigo has developed since.

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Bendigo in 1851

This historical sketch map gives important context to what Bendigo actually was like before the gold rush in 1851. The flowing creek and broad natural landscape, as well as a few tents pitched by the creek is a great reference point. Around christmas in 1851 there were about 800 people on the gold feild, by June of the next year there was close to 20,000.

Map: William Sandbach The Infancy of Bendigo – Golden Square in 1851 in George Mackay [Ed.], The Annals of Bendigo, 1851-1867, Volumes 1-5, Bendigo, Cambridge Press.

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1959 How did the discovery of gold influence settlement during the first wave of mining? By the late 1850’s there thousands of people working the alluvial soils of the creek banks through puddling machines. This map is taken from the Royal Commision called the sludge commission. Due to the degradation of the creek and the way the land was being exploited the creek was canalised. In this sense, the location of where the gold was found and how it was extracted, and the canalisation of the creek influenced the initial location and layout of the city.

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There is also a clear relationship with these historical maps and the current distribution of remnant vegetation.

Data:

Data:

Map: Victorian Government Report “Removing the Sludge from the Gold Fields” - https://www.parliament.vic.gov.au/papers/govpub/VPARL185960No7.pdf

Native Vegetation - Modelled 2005 Ecological Vegetation Classes https://discover.data.vic.gov.au/dataset/native-vegetation-modelled-2005ecological-vegetation-classes-with-bioregional-conservati-wms


What is the relationship between this initial settlement and the underlying geology? This map shows the clear relationship between the layout of the city and the alluvial soils in which the gold was first found. The methods of extracting gold in the first instance meant that proximity to the Bendigo creek was a very important factory, and the fact the subsequent development of streets and buildings all align with the underlying geology shows the significance of this influence.

What happened next?

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000

Waterways Fluvial Deposits

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1871 The key features of these maps is how the city is expanding laterally; rather than along the hydrological lines it is expanding across them. These maps show the devision of land into new mining lease holds and represent a shift in land use.

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1872 Map Reference:

Map Reference:

Victoria. Dept. of Mines. Munro, Nathaniel, & Victoria. Department of Mines. (1871). Mining surveyors’ map of the district of Sandhurst [cartographic material] : showing the different companies and ground leased up to 1st Nov., 1871 / compiled from the latest plans in the government offices and authentic surveys by Nathaniel Munro. [Melbourne: Dept. of Mines].

Smyth, R. B., MacKay, A., Couchman, T., Murray, R. A. F., & Shepherd, R. (1873). Sandhurst gold field. [Melbourne: [Melbourne : Dept. of Mines.


How did the secondary wave of gold mining influence the layout of Bendigo? The key feature of this map is the relationship between the land held for mining leases and the Geology. There is a significant shift away from how gold was mined, moving away from the alluvial soil to the older sedimentary rock shown in pink. There is some kind of relationship between the location of these new areas of activity and the current existing city boundary.

How did these shifts in land use further influence the layout of Bendigo?

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000 Map Reference: Smyth, R. B., MacKay, A., Couchman, T., Murray, R. A. F., & Shepherd, R. (1873). Sandhurst gold field. [Melbourne: [Melbourne : Dept. of Mines.

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Sedimentary Rock

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How did the secondary wave of gold mining influence the layout of Bendigo? This map really begins to highlight the lateral expansion across the hydrological lines. While the actual mining of the gold appears to be more related to the sedimentary rock, the layout and distribution of different parts of the city are still closely related to the fluvial soils. In these maps, we can see the blacked out areas punctured with gold mines would have been a hive of activity, but also probably a pretty awful place. How the settlement arose around these areas can be clearly related to the topography, fluvial soils and drainage lines. These strong clear linear relationships acros the landscape guide the research moving forward.

A

What is the relationship between these historical land holding and mine shafts, and the current landscape?

Data:

B

Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000 Historical mining activity https://discover.data.vic.gov.au/dataset/historical-mining-activity Map: Smyth, R. B., MacKay, A., Couchman, T., Murray, R. A. F., & Shepherd, R. (1873). Sandhurst gold field. [Melbourne: [Melbourne : Dept. of Mines.

Waterways

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A

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Drainage Gullies

Settlement

There are a number of key drainage lines which indicate how water and ‘sludge’ was to be moved from site. These are key areas because the research shows they would have been pretty foul, which would obviously have prevented people settling there.

This Western area appears to show the most substantial areas of settlement. The area is away from areas held by mining leases and protected by the drainage line which would have been across the alluvial soil.

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3D Visualistions These visualisations provide several valuable learnings on the project. Firstly, they demonstrate the surrounding landscapes Bendigo. It shows the city is nestled in between mountains, and highlights the extent of the fluvial soils in between the mountain ranges running through the centre of Bendigo. The visualisations also bring a focus to the strong linear nature of the historical mineshafts. By incorporating

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a 250m buffer around the mine shafts, the clear spatial links between them are really obvious. The process of working in 3D has provided a clear way forward in terms of wanting to explore these areas, and provides a lens through which to analyse the current Bendigo landscape.


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How can these patterns influence future development strategies?

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What is the relationship between historical land holding and mine shafts, and the current landscape? This map identifies the historic mine leases and mine shafts (with a 250m buffer). It shows the concentration of these types of landuses over a specific area of Bendigo. This map opens the door for further maps which can highlight these areas, and allow for a closer investigation of the satelite images to understand what the ground conditions of current day Bendigo are like.

What is happening on the ground in these areas?

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000

Historical mining activity https://discover.data.vic.gov.au/dataset/historical-mining-activity

Fluvial Deposits

Historic Mine Shaft 0

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Waterways

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What is happening on the ground in these areas? The map provides 2 clear frames within the Bendigo Boundary which reveal potential areas of interest. These options allow a zoom in to attempt to unpack and draw out relationships through visual analysis of the satelite images, within the set frame.

How could these relationships inform design or planning strategies?

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000

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Historical mining activity https://discover.data.vic.gov.au/dataset/historical-mining-activity Satelite Image

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Fluvial Deposits

Historic Mine Shaft

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Waterways


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Sparse Density at the Urban Edge

Settlement Patterns around historical mine shafts

The Density in these areas looks really low, with quite a lot of open land which appears vacant. This is a stark difference the other parts of Bendigo where the residential development is much more dense.

This map is really interesting because it focuses in on the lines of historic mine shafts, and there seems to be some patterns in the way the land appears. Much of the previous mine sites appear undeveloped. It is interesting to see what opportunities these strings of undeveloped land could provide.

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How could these relationships inform design or planning strategies? By re-introducing the remnant vegetation layers, there is another clear relationship which is brought to light. The patterns historical mining within the boundary of Bendigo have intersected the vegetation, breaking a connection across the city. By focusing in on the undeveloped land related to the historical mining, it is possible to draw out new relationships which could inform green links or connections.

What are the implications on the ground?

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000

Historical mining activity https://discover.data.vic.gov.au/dataset/historical-mining-activity Satelite Image Native Vegetation - Modelled 2005 Ecological Vegetation Classes https://discover.data.vic.gov.au/dataset/native-vegetation-modelled-2005ecological-vegetation-classes-with-bioregional-conservati-wms

Historical Mine Shafts Historical Mine Lease Holdings City of Bendigo Regional Boundary Victorian Regional Footprints Waterways 20m Contours Remnant Vegetation Alluvial / Wetland Dense Bush / Forest 0

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Open Grassland


What are the implications on the ground?

Many of the areas within these linear historical mining corridors are undeveloped. The strong linear land patterns in which land was divided and mined has created a current opportunity for these sites to be encorporated into a green network which can influence and improve the way the city grows. These patterns, derived from historical land use practices over 100 years ago can now infrom a new strategy of development. The network provides opportunities to connect fragmented vegetation communities across the city, but also recreational and functional transport routes for the community.

How could these relationships inform design or planning strategies?

Data: Geological units represented as two dimensional polygons (1:250,000) https://discover.data.vic.gov.au/dataset/geological-units-represented-astwo-dimensional-polygons-1-250000geological-units-represented-as-twodimensional-polygons-1-250000

Historical mining activity https://discover.data.vic.gov.au/dataset/historical-mining-activity Satelite Image Native Vegetation - Modelled 2005 Ecological Vegetation Classes https://discover.data.vic.gov.au/dataset/native-vegetation-modelled-2005ecological-vegetation-classes-with-bioregional-conservati-wms

Railway Corridors Existing Railway Stations Future Railway Station Historical Mine sites in Green space Historical Mine sites Linear Connections City of Bendigo Regional Boundary Victorian Regional Footprints Existing Under-used Green Space Green Connections 100m offset from relevant historical mines 20m Contours Remnant Vegetation Alluvial / Wetland Dense Bush / Forest Open Grassland

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Conclusions An understanding of the practices and patterns which informed Bendigos initial settlement have been shown to still exist in the landscape today. An uncovering of these traces informs mappings which draw on the past to deal with future growth. These green networks and corridors can inform new housing typologies, commuter transport networks, locations for new infrastructure including a train station for the high speed rail, as well as providing connectivity across the city between the fragmented vegetation communities. The use of historical maps in combination with newer types of spatial data allows maps to draw out these broad relationships across a range of physical and temporal scales. This methodolgy is significant because it really promotes a deep understanding of the settlement patterns and historical decisions which have lead to a place being how it is. This in depth knowledge allows unique perspectives to be drawn out from the research, and informed design decisions to be made

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