Spatio-temporal analysis of graffiti occurrence in an inner-city urban environment.

Billy Haworth, Eleanor Bruce, Kurt Iveson *

*School of Geosciences, University of Sydney

Applied Geography

Abstract

Graffiti management often presents policy challenges for municipal authorities.

However, the inherent diversity of graffiti culture and its role in defining urban

space can be neglected when formulating response strategies. This study

investigates spatio-temporal trends in graffiti across inner-city Sydney, New

South Wales to support alternative perspectives on graffiti and its role in urban

landscapes. Graffiti removal incidence records were geocoded to examine

graffiti distribution across the City of Sydney Council Local Government Area

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over a six-month period. Graffiti removal ‘hotspots’ were identified using spatial

cluster analysis and shifts in graffiti activity were examined through trend

analysis. Specific sites within the Local Government Area were identified as a

focus for repeated graffiti removal activities. Finer spatial scale GPS based

mapping for a selected graffiti hotspot area in the suburb of Surry Hills showed

diversity in graffiti form. While the rate of return may have decreased in the Surry

Hills case study, the overall number of graffiti removal incidents increased.

Rapid-removal policies can change the location, form and diversity of graffiti

encouraging ‘quick and dirty’ forms of graffiti over more complex design works.

Spatio-temporal variability in graffiti occurrence across inner-city Sydney

highlights the need to consider graffiti as a diverse urban phenomenon when

attempting to understand its occurrence and formulate response strategies.

Keywords: graffiti; spatio-temporal analysis; urban space; cluster analysis; GIS

1. Introduction

Graffiti is a prominent feature of urban landscapes, and graffiti culture plays an

important role in defining the identity of urban environments. In the past graffiti

has been conflictingly labelled as ‘art’ or ‘vandalism’ (Gomez, 1993). Some

people find graffiti attractive, while others see it as an index of social decline and

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youth criminality (Halsey & Young, 2002). The notion of graffiti as vandalism

continues to challenge municipal authorities and policy makers all over the world.

In reality, however, there is much greater diversity within graffiti culture than the

simple binary dichotomy of art or vandalism permits.

Recent forms of graffiti spawned from hip hop culture in the 1970s as part of a

larger alternative youth culture expressing new forms of music, dance, and art

(Ferrell, 1995; Halsey & Young, 2002, 2006). Gomez (1993) makes the

distinction that ‘graffiti art’ describes graffiti-type works that exhibit many of the

characteristics of pieces normally termed ‘high art’ or ‘folk art’, as they are

motivated by a desire to create art; and ‘graffiti vandalism’ describes works that

are motivated by a desire to mark territory, create notoriety, or show one’s

defiance of the law and society. Most writers are motivated by the desire for

recognition rather than by the urge to rebel (Gomez, 1993). Do these writers

motivated by a desire for recognition fall into both categories then? A key

publication on modern graffiti culture and policy by Halsey and Young (2002)

challenges this dichotomy and states that Gomez’s division is limited in an

Australian context.

Halsey and Young (2002) identify four distinct forms of graffiti: tagging, throw-

ups, pieces, and slogans. Tagging and pieces (‘masterpiece’) are considered

hip-hop forms of graffiti, whereby distinctive calligraphy, images, and colours are

used to write signatures or paint murals (Halsey and Young, 2002). Pieces are

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larger-scale and time-consuming work, often involving complex graphic design

(Dovey, Wollan, & Woodcock, 2012). A ‘throw up’ is similar to a tag, but often

larger and in bubble writing. Slogans cover a range of topics from politics to the

expression of love. To this list, we could add stickers, posters, stencils and even

knitting as new forms of graffiti that have emerged in recent years. These

different forms of graffiti are produced by different individuals for different

reasons, and may have different impacts on the community around them (Halsey

and Young, 2002). Yet this heterogeneity is rarely acknowledged, despite its

important implications for the likely success of any graffiti-related strategy

(Halsey and Young, 2002).

Urban authorities tend to treat all forms of unauthorised graffiti as vandalism or

crime. In addition to being the object of municipal regulatory strategies, graffiti is

also regulated through the criminal law, where it is classified as damage to

property and a range of statutory provisions in the various States covers most

aspects of the activity (Halsey and Young, 2002). Local government agencies,

transport authorities, schools, industries and householders spend significant

resources removing graffiti. The financial cost across Australia of graffiti removal

is estimated to be 200 million AUS dollars per year (Ovenden, 2007). Responses

by authorities for addressing the perceived graffiti problem are varied. Ovenden

(2007) identifies two main approaches to graffiti management. The first involves

continuous funding of graffiti removal programs, and the second is to establish

graffiti prevention initiatives.

Rapid removal is the dominant response in Australian cities. This is an effort to

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re-appropriate the space, both taking back the space from the graffiti writer, and

returning it to a condition of propriety (Halsey and Young, 2002). Removal

strategies invest hope in the notion that prompt cleaning will deter subsequent

writing – otherwise removal simply provides a clean surface for the next piece or

tag (Halsey and Young, 2002). The City of Sydney council states that “to remove

graffiti as quickly as possible as a deterrent” is a key objective of their graffiti

management policy (City of Sydney, 2004). This type of response is related to

the theory proposed by Wilson and Kelling (1982) of “broken windows” (see

Doran & Lees, 2005; Iveson, 2010). Central to this argument is the notion that if

a window in a building is broken and left un-repaired, the other windows will soon

be broken because the community interprets the first broken window as a sign

that no-one cares (Doran & Lees, 2005; Wilson & Kelling, 1982). The theory

infers if graffiti is left unchecked it will lead to an increase in the occurrence of

graffiti, and possibly to more serious forms of crime. Based on the “broken

windows” perspective, not only is graffiti intolerable, the toleration of graffiti is

intolerable (Iveson, 2009). This concept has influenced research and policy-

makers since its inception (see Doran & Lees, 2005; Sampson & Raudenbush,

1999; Skogan, 1990; Moreau and Alderman, 2011).

Alongside this approach which deems no type of graffiti acceptable (Halsey and

Young, 2002), some urban authorities also implement welfarist strategies that

involve outreach work through a youth worker; provision of community programs

to deflect towards other activities; and attempts to provide job-training schemes.

A response centred upon acceptance of graffiti culture might involve

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commissioning of murals, or community education and the provision of art

classes or workshops (Halsey and Young, 2002). Graffiti writing has been used

as a form of ‘art therapy’ as a tool for dealing with troubled adolescents (See

Linesch, 1988; Fliegel, 2000). Effective therapists must have the ability to speak

the language of their patients’ inner world if they are to promote growth within

their patients’ psychic structures (Linesch, 1988). Acknowledging and utilising

graffiti as the individuals preferred form of communication as opposed to

removing the communication entirely may be useful in reducing illegal graffiti.

Hanauer (2004) reports in the case of the assassination of Israli Prime Minister

Rabin artistic expression in the form of graffiti was seen to allow social bonding

and mitigate feelings of bereavement, guilt and disbelief, and that the erasure of

this communication effectively reclaimed symbolic ownership of the trauma event

as political. Acceptance of graffiti culture is often linked with other strategies, and

removal of illegal graffiti may still occur, but particular spaces or facilities may be

made available for the use of graffiti writers

In debates about which of these approaches to reducing graffiti is most effective,

the question of how ‘success’ can be measured is crucial. Advocates of each

approach struggle to provide statistics which can prove that their strategy has

‘worked’ by reducing the incidence of graffiti in a particular location. So, for

example, the prevention initiative ‘Artforce,’ aims to significantly reduce the

recurrent cost of cleaning graffiti from traffic signal boxes in Brisbane, QLD; by

implementing original artwork by the community. A report evaluating the efforts of

this strategy over a seven year period found that the reduction of graffiti on

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painted compared to unpainted boxes was consistent across Brisbane, with

unpainted boxes accumulating graffiti three times faster than painted traffic signal

boxes (Ovenden, 2007). The study by Ovenden (2007) demonstrated that

significant cost reductions could be achieved by implementing anti-graffiti,

compared to graffiti-removal, programs.

And yet, measures of success which focus only on the reduction of ‘graffiti’ have

significant limitations. Most importantly, they fail to distinguish between different

types of graffiti or to take account of the evolving dynamics of graffiti writing, and

this has a series of perverse consequences. For example, while removal of

some forms of graffiti might be welcomed by the wider public, the removal of

other forms of graffiti might be viewed as a mistake. In Melbourne, a Council

graffiti removal crew infamously painted over the last remaining stencil by world-

famous street artist Banksy, causing local outrage and an international media

storm. A study of community attitudes to graffiti in Melbourne found that a

majority of residents of several inner city neighbourhoods believed that some

forms of graffiti actually added to the character of their neighbourhood, thereby

improving their quality of life (Dovey et al, 2012). Further, several observers have

argued that removal and/or prevention strategies might reduce some forms of

graffiti, while actually promoting others (Austin, 2001; Ferrell and Weide, 2010).

Rapid removal is widely credited with pushing graffiti writers into quicker forms of

graffiti such as tags and stickers, which require less time and resources to

execute than more elaborate pieces and mural (Iveson, 2009). Ironically, in light

of Dovey et al’s findings in Melbourne, these quicker forms of graffiti (especially

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tags) are often the forms which the wider community tends to dislike the most. As

well as changing the form of graffiti, rapid removal may also result in changing

locations of graffiti, ‘displacing’ rather than reducing its occurrence by pushing it

into different places (Iveson 2009; Ferrell and Weide 2010, Young 2010).

2. Background: Examining graffiti space through spatio-temporal analysis

A deeper awareness of the spatial and temporal patterns of graffiti occurrence

may provide insight on urban graffiti culture and debates about its management

in cities. Through the use of geographical information systems (GIS) we have

the potential to spatially and temporally model both graffiti and its place within the

urban environment, and the efforts of removal strategies, to quantify these trends

and theories of displacement.

GIS technologies have been used by researchers, government agencies, and the

commercial world for examining spatio-temporal relationships and patterns in a

wide range of urban contexts. However, research involving the use of GIS in

examining issues associated with urban place and space has been relatively

recent (Steinberg & Steinberg, 2006), reflecting the emergence of qualitative GIS

and new methods for incorporating contextual detail within GIS representations.

Responding to the GIS critiques of the 1990s (see Schuurman, 2000) in which

GIS was perceived as rooted in positivist epistemologies, qualitative GIS

emphasises the integration of multiple knowledge forms (Elwood & Cope, 2009).

GIS is well established as a central discipline in urban planning (Lejano, 2008),

but the application of qualitative GIS as a valid research methodology within

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social, cultural and critical human geography is recent (see Pavlovskaya, 2009).

Examples include research by Kwan (1999) in which space-time geography was

used to model individuals’ movements to show gendered uses of urban space

and work by Matthews, Detwiler, and Burton (2005) in which urban ethnographic

data is combined with census and crime statistics. In mapping queer oral

histories Brown and Knopp (2008) noted that collisions between epistemologies

underlying ethnographic methods and GIS technologies were an important

process in the production of multiple and hybrid forms of spatial data. Research

by Elwood (2002, 2006) in critical and participatory GIS demonstrates use of GIS

in qualitative research. Recognition of the socially constructed nature of spatial

data and maps is central to debates in the critical cartography and GIS literature

(Brown and Knopp, 2008; Wilson, 2011).

More recently in Australia, Gibson (2010) explored the role of GIS in cultural

mapping and highlighted benefits of adopting an interdisciplinary approach by

deploying mapping technologies from the realm of geographical sciences and

applying them to cultural research questions. Gibson (2010) also acknowledged

problems associated with mapping an urban phenomenon such as cultural

space, including the nature of maps to embody uneven power relationships, and

the ethical question of how maps can add to the increasing surveillance of

society, which are both relevant issues to the current study.

Graffiti culture has not received the same focus in the application of GIS as

creative space (see Brennan-Horley & Gibson, 2009; Gibson, 2010). Academic

research on the use of GIS in mapping graffiti has focused on graffiti vandalism

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and crime mapping. Rapid geocomputing advancements and sophisticated

visualisation capabilities motivated interest in the development of GIS techniques

for understanding the occurrence of criminal activity (Murray, Mcguffog, Western,

& Mullin, 2001). Murray, et al. (2001) used GIS-based techniques to map crime

in Brisbane, QLD, through visualizing crime in relation to other spatial layers

(including railways, roads, public transport, supermarkets, police stations, fire

stations, city centre and river), and integrating exploratory techniques (clustering

and geostatistics) to quantify the spatial distribution of crime.

Doran and Lees (2005) used GIS to investigate links between social and physical

disorder, crime, and the fear of crime, paying particular attention to graffiti. They

argue that GIS can provide a useful approach for government agencies

responsible for reducing the fear of crime, disorder, and the occurrence of crime.

The combination of qualitative community surveys and quantitative GIS methods

to map and analyse correlations between community perceptions and actual

crime occurrence provided an insightful approach for reducing the perception of

crime and therefore actual occurrence. However, Doran and Lees (2005)

highlighted the limitations of a small population sample restricted to a short time

period. Longitudinal data and a comprehensive sampling design strengthen

effective use of quantitative methods for analysing patterns in social landscapes.

Emerging work focuses on applications of GIS to examine spatio-temporal trends

in graffiti pattern in the context of crime. A growing number of urban authorities

are collecting geospatial data about the incidence and location of graffiti as they

remove it (Iveson 2010). The stated purpose here is twofold – both to assist in

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the prosecution of individual graffiti writers by developing a record of their

activities, and to identify locations of high concentrations, or ‘hotspots’, to thereby

facilitate better-informed decisions on the management strategies employed in

such areas.

And yet, the spatial data about graffiti collected as part of crime-mapping efforts

also has significant limitations. When urban authorities seeking to reduce illegal

graffiti collect graffiti data, they are primarily interested in the occurrence of graffiti

and less interested in the form or quality of different incidents of graffiti.

However, in light of our analysis above, we would argue that data about form as

well as location is essential for efforts to consider the place of graffiti within the

broader social landscape. The analysis of removal data may be useful in

evaluating the impact of existing graffiti management strategies in the context of

debates discussed above – are removal efforts leading to the overall reduction in

graffiti to which they aspire, or are they only displacing graffiti to other locations

as their critics suggest? But they will have much less to tell us about the different

forms of graffiti written in different urban environments, and their different impacts

on urban character.

To address such limitations, analysis of spatio-temporal trends in graffiti

occurrence and mapping graffiti by type or form will be necessary to provide a

more detailed understanding of the diversity and heterogeneity associated with

graffiti. The current study will therefore also examine the dynamic nature of

graffiti distribution and explore local scale patterns in graffiti diversity. By

considering graffiti within a broader social landscape as its own dynamic urban

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phenomenon this paper attempts to extend spatio-temporal analysis of graffiti

beyond criminology to examine the spatial practice of graffiti.

3. Geospatial analysis of graffiti in the City of Sydney

In the rest of this paper, we test some of these claims about the use of GIS for

informing different approaches to graffiti management through a case study of

the City of Sydney Local Government Area (LGA). The City of Sydney spends

over AUS$3 million on graffiti removal (Creagh, 2008). The City of Sydney

Council (2004) defines graffiti as "any inscription, word, figure or word design that

is marked, etched, scratched, drawn, sprayed, painted, pasted, applied or

otherwise affixed to or on any surface". Interestingly, this definition includes no

mention of whether the inscription, word, figure or word design is authorised –

the urban landscape is of course full of inscriptions (not least outdoor advertising

and the City’s own signage), and presumably Council seeks only to target

unauthorised inscriptions with its policy. Their rigorous approach to graffiti

removal, inspecting some sites for graffiti removal every 24 hours, and others

every five days (City of City of Sydney, 2004) has resulted in a detailed and

continuous time series dataset that captures the highly dynamic nature of graffiti

use across the LGA. The City of Sydney LGA (Figure 1) covers approximately

26 square kilometres and is home to 177,000 people, with the highest density of

residential and commercial use in Australia (City of City of Sydney, 2011). The

City of Sydney also supports major tourist and cultural attractions and includes

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extensive parks and open space.

Fig. 1. Location of the City of Sydney Local Government Authority and suburbs.

Determining the spatial distribution of graffiti removal hotspots within the City of

Sydney LGA, assessing spatial and temporal trends, and identifying diversity

associated within these identified hotspot areas involved three main steps.

These included collation and geocoding of graffiti removal data, spatial clustering

analysis and local scale analysis.

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3.1 Mapping and Analysis of the City of Sydney’s Graffiti Removal Data

3.1.1 Methods

Graffiti removal data collected between February 2010 and July 2010 inclusive

was provided by the City of Sydney council. The City of Sydney council

outsources the removal of graffiti to a private commercial organisation who

record detailed information about each removal incidence. Data covering a six

month period between February and July 2010 were made available by the City

of Sydney for the purposes of this study. While data over a longer time period

would have been preferable, this time period still provided us with a significant

number of graffiti removals for analysis (over 12,000, see below). These data

were provided in Excel format and included the address location of each graffiti

incident, the type of graffiti (chalk, spray paint, texta, and other), surface (e.g.

wall, fence, pole, gate, street sign), surface substrate (e.g. painted, brick), date

the incident was observed and the date the graffiti was removed.

Locational data provided in street address form was spatially referenced through

geocoding (address matching) using the Whereis® Sensis street map of Sydney

as the reference dataset (stored in MGA94). Geocoding converts the location

descriptions (street number and name) into a set of Cartesian coordinates.

Unmatched addresses were manually checked and assigned locations where

sufficient address information was provided.

Clustering analysis was done to examine the spatial distribution of graffiti

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removal occurrences. Average nearest neighbour analysis was performed on all

geocoded graffiti removal points to determine whether locations were clustered

based on distance (Ebdon, 1985). This analysis examines the distances

between each point and its nearest neighbour, then compares these to expected

values for a random sample of points (Aldstadt, Chen, & Getis, 1998). The

Getis-Ord Gi* test was performed to investigate the extent to which a location is

surrounded by a cluster of high or low values (Ord & Getis, 1995). Positive G i*

values indicate statistically significant spatial clustering of high values (graffiti

hotspots) and negative values indicate statistically significant spatial clustering of

low values (graffiti cold spots). The cluster analysis requires the graffiti removal

incident data to be aggregated into spatial units (polygons) containing incident

frequency. A 100m vector layer containing the number of graffiti removal

incidents in each 100m block was generated for the study area using the fishnet

and spatial join functions in ArcGIS. The Global Moran’s I statistic for spatial

autocorrelation was performed, using the zone of indifference method, to

determine an appropriate distance band for the Getis-Ord analysis. The distance

band defines which features (100m analysis blocks) are included in the analysis

for each feature or block. Global Moran’s I statistics was calculated for all graffiti

removal incidents using distance bands from 200m to 1200m at 100m intervals.

The Getis-Ord analysis was then performed on incidents occurring each month

within the study period and on total incidents.

In addition to the spatial cluster analysis, a density surface was generated within

ArcGIS, using a circle neighbourhood and radius of 500m based on the February

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and July incident data to examine temporal differences and spatial shifts. The

density search radius calculates the total number of graffiti incidents within the

specified distance as a proportion of the total area and assigns that value to the

cell in the output surface.

The graffiti removal data provided by the City of Sydney had a number of

problems – in particular, it included entries that lacked explicit street address

details, predominantly due to the type of surface on which the graffiti was

marked. For example, street addresses were not recorded for graffiti

occurrences on public bins, traffic light poles, public benches, or pavement and

thus these incidences could not be geocoded and were excluded from the

analysis. The City of Sydney database contained 18,272 graffiti record entries

with address details, approximately 67% of these records provided sufficient

detail for geocoding and inclusion in the analysis. Table 1 shows the

percentages and total number of graffiti removal incidences that were geocoded

for each month between February and July 2010.

Table 1. Percentage and count of graffiti removal incidences geocoded for each month.

Month Geocode match (%)

Count of incidences geocoded

February 63 1903

March 69 1944

April 66 1933

May 67 1604

June 65 2318

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July

Total

72 2540

12,242

3.1.2 Spatial clustering: results and discussion

The Average Nearest Neighbour Index calculated using all graffiti removal

records was 0.094, with a z-score of -175.99 and p-value of 0. The null

hypothesis states that graffiti removal incidents are randomly distributed. The

index clearly indicates that the pattern exhibits clustering and the z-score and p-

value returned in this analysis confirms the null hypothesis can be rejected within

a 99% confidence level. However, results of the Average Nearest Neighbour

analysis is limited as it determines the presence of clustering based only on

location of the sample features and not the values of an attribute associated with

those features. Further analysis was done to examine the clustering of graffiti

frequency. The null hypothesis for the Global Moran’s I analysis states that the

frequency of graffiti removal incidents is randomly distributed across the study

area. A p-value of 0 was returned for the Global Moran’s I statistic calculated for

each distance band allowing rejection of the null hypothesis and confirming

incident frequency tends to cluster spatially. Results of the Global Moran’s I also

showed a drop in z-score at the 900m distance band indicating this is an

appropriate distance band. The Global Moran’s I statistic was used to determine

a distance threshold or lag distance that reflects maximum spatial

autocorrelation. However, conceptually 900m was considered too large a

‘sphere of influence’ to be meaningful when examining patterns of graffiti

behaviour and removal activities. The spatial processes underlying graffiti

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activity operate at multiple spatial scales but the interactions of interest in this

study are more likely to occur at a neighbourhood level rather than suburb level.

For this reason a distance threshold of 500 metres was selected. Results of the

Getis-Ord Gi* analysis are shown in Figures 2 and 3. These figures demonstrate

defined areas of statistically significant graffiti removal hot spot and cold spots

and temporal variation in the extent of these areas over the six month study

period. Figure 4 depicts the spatial shifts from February to July 2010 with darker

areas on the map representing an increase in graffiti removal, and light areas a

decrease over the six-month period.

Fig. 2. Map depicting high and low areas of all geocoded graffiti removal incidents recorded

between February and July 2010. High Getis-Ord Gi* z-scores, shown in red, indicate more

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intense clustering of high incidents (hot spots). Low z-scores, shown in blue, indicate more

intense clustering of low incidents (cold spots).

Fig. 3. Map depicting high and low areas of all geocoded graffiti removal incidents recorded in

2010 on a monthly basis. High Getis-Ord Gi* z-scores, shown in red, indicate more intense

clustering of high incidents (hot spots) and low z-scores, shown in blue, indicate more intense

clustering of low incidents (cold spots).

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Fig. 4. Density map showing changes in graffiti removal incidences between February and July 2010. Darker areas indicate an increase in graffiti removal and lighter areas indicate a decrease in graffiti removal over the six month period.

As can be seen, there are several areas within the City of Sydney with

statistically significant clusters of high graffiti occurrence or ‘hotspots’ and

clusters of low occurrence or ‘cold spots’ (Figure 2). From our analysis of the

data provided by the City of Sydney, it is possible to draw two tentative

conclusions about the removal efforts of Council and their impact on graffiti and

its geographies. First, we would like to make a simple but significant

observation: rapid removal of graffiti over the six month period for which we have

data shows no signs of reducing the amount of graffiti across the City. The

number of incidences of removal in fact increased during the period. Rapid

removal is premised on the notion that it will deter graffiti writers, but even if

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individual writers are deterred when their work is removed, clearly graffiti

continues to be written in similar volumes.

Second, the location of graffiti ‘hot spots’ seems to have shifted during the 6

month period for which we have data. High densities of graffiti removal in

particular areas are present each month. Particular areas within the LGA

experienced increases in graffiti removal, such as Surry Hills, and others

experienced overall reductions in graffiti removal, such as Waterloo (Figure 4).

The Newtown/Erskineville graffiti hotspot present in February is absent in March

and April and appears again in May (Figure 3). In the suburb of Glebe a clear

graffiti hotspot is observed in April, has expanded south in May and June and

contracted to a much smaller area in July. This variability in spatial patterns of

graffiti removal emphasises the dynamic nature of graffiti occurrence. Does this

shifting geography of graffiti removals confirm theories that graffiti removal efforts

are more likely to displace graffiti than reduce it? Further qualitative research

would need to be conducted with both graffiti writers and removal contractors to

answer this question with any certainly, but the quantitative evidence presented

here suggests that the displacement thesis may have some merit.

There is much that this data does not tell us. Most importantly, the data collected

by graffiti removal crews for the City of Sydney tells us nothing about the qualities

of the graffiti removed. Given the growing recognition that different forms of

graffiti can have different neighbourhood effects (Dovey et al 2012), and the

wider claims that rapid removal may result in changing form as well as changing

location of graffiti (Iveson 2009), this is a significant limitation.

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3.2 Local scale analysis of graffiti in Surry Hills locality

3.2.1 Methods

In order to address some of the limitations of the data provided by the City of

Sydney, a locality within the LGA was chosen for further data collection and

analysis. The Getis-Ord statistics were used to identify a local case study area

for analysis at a finer spatial scale. The cluster analysis identified several areas

within the City of Sydney as significant graffiti removal hotspots. However, the

suburb of Surry Hills was selected from these hotspots due to its local reputation

as an alternative area within inner Sydney. It is an area with several major

thoroughfares to the city centre, as well as local interconnecting streets and alley

ways less visible to everyday passers-by. Due to the mix of high and low traffic

areas and the presence of ‘priority zones’ (streets inspected every 24 hours to

identify graffiti incidents for removal) there is spatial variability in graffiti

management effort within this small area making Surry Hills a diverse and

interesting case study. The average number of graffiti incidences per day and

the average amount of time between each day with at least one graffiti removal

incident within the Surry Hills hotspot area were determined. Regression trend

analysis was performed on the data to examine temporal trends.

To add to this Council data, one of the authors collected graffiti incidence data in

two hotspot areas within Surry Hills (Figure 5) in January 2011 using a Trimble

Juno ST handheld Global Positioning System (GPS) and ArcPad 7.1. Graffiti

type, size, the media used, the surface type, a photo of the incident, and whether

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there was evidence of pervious graffiti at the site were recorded for all incidences

within a 33, 000 sq m study area between Elizabeth St, Albion St,

Commonwealth St, and Foveaux St, and a 24, 000 sq m study area bound by

Riley St, Albion St, Crown St, and Foveaux St. The data were imported as a

point shapefile into ArcGIS 10, and graffiti incidents were classified based on

type and media used.

3.2.2. Surry Hills study: results and discussion

Graffiti occurrences removed from the Surry Hills hotspot (Figure 5) for the period

February to July 2010 are summarised in Figure 6. Average graffiti removal rate

within the Surry Hills case study was calculated as 16.7 graffiti removal

occurrences per day. For the same period the average days between graffiti

removal incidents was calculated as 1 removal somewhere within the identified

Surry Hills hotspot area every 1.5 days (Figure 7). The trend analysis results are

shown as a red line on each graph. Graffiti removal at the Surry Hills hotspot

presents a trend of increasing graffiti removal through time, with an increase in

the number of days between removals.

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Fig. 5. Location of the Surry Hills case study field site within the City of Sydney.

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Fig. 6. Frequency of graffiti removal incidences within the Surry Hills hotspot between February

and July 2010 with associated trend line shown in black.

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February March April May June July1

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Fig. 7. Average days between graffiti removal incidences in the Surry Hills case study removal with the trend line shown in black.

In total 231 individual graffiti incidences were identified in the two field survey

sites over a two-day period. The spatial distribution of the graffiti occurrences,

and the graffiti form identified for each occurrence is shown in Figure 8.

Evidence of previous graffiti was present at 79% of mapped incident locations.

Tags were the most frequently occurring type of graffiti (Figure 9) and texta,

paint, and spray paint were the most common types of media used to mark the

graffiti (Figure 10). Figure 11 shows two examples of the type of graffiti work

observed during the field study.

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Fig. 8. The spatial distribution and diversity of form of mapped graffiti incidences in two Surry Hills graffiti hotspot sites.

Tag77%

Sticker13%

Throw-up4%

Slogan2%

Piece2%

Other3%

Graffiti Types

Fig. 9. Percentages of different graffiti forms mapped in the Surry Hills survey.

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Chalk3%

Crayon1%

Ink on paper4% Mixed media

1%

Other2%

Paint25%

Paper1%

Scratching5%

Spray paint24%Spray stencil

2%

Sticker3%

Texta26%

Texta on paper3%

Media Used

Fig. 10. Percentages of different media used for graffiti mapped in the Surry Hills survey.

Fig. 11. A) Tags repeatedly marked over top a throw-up. B) Competing tags.Images of graffiti occurrence identified during the Surry Hills field survey, January 2011. Just two images of graffiti locations are presented, however these images represent an example of what was observed at many locations within the study site.

The graffiti occurrence data captured during the GPS survey in Surry Hills

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(Figures 8-10) presents a diverse range of graffiti types, from Hip-hop forms such

as tags and throw-ups, to more artistic forms such as stickers and pieces. The

different forms of graffiti do not appear to present a specific spatial pattern based

on type, but highlight the overall diversity within the culture of graffiti occurrence.

A spatial pattern of graffiti distribution does appear to exist in relation to street

type, however (Figure 8). What does this data tell us?

First, graffiti appears to occur more on the smaller and quieter streets as

opposed to what would be considered main roads. The major traffic

thoroughfares of Elizabeth Street, Albion Street, and Foveaux Street exhibit

relatively little graffiti in comparison with the smaller streets and alley ways

interconnecting them. This could reflect the fact that City of Sydney targets these

major roads for graffiti removal more frequently than other street types. It could

also be a result of the behaviour of the graffiti writers themselves. With less

traffic and less street-lighting more time is permitted to write and the ability to

remain hidden (both from authorities and other writers) is increased. Writers may

also be actively avoiding the main thoroughfares as they are aware that is where

their work will be removed more rapidly (see below).

Second, in relation to land use, a notable amount of graffiti incidences were

identified in the light industrial laneways west of Commonwealth Street (Figure

8). No graffiti was found on individual residential properties, and if graffiti was

found in a residential area it was on a piece of public property such as a

telegraph pole or road sign. In interviewing graffiti writers in Melbourne, Halsey

and Young (2006) noted that graffiti writers often maintain ethical taboos as to

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which surfaces can be written on. Residential property was cited as taboo

alongside churches and cemeteries, cars, war memorials, and ‘anything natural’

(such as trees). The majority of graffiti identified in the Surry Hills field site

occurred on commercial or industrial walls or public structures.

Third, the fact almost 80% of occurrences showed evidence of other or previous

graffiti at the location indicates a high level of interaction between the artists .

Many of the graffiti were marked directly over the top of other graffiti (Figure 11).

This was particularly consistent with the practice of tagging. Often the same tag

was marked repeatedly over other work in the same area, in what appeared to be

an effort by the writer to claim a dominant presence on the wall from their rivals.

The more a signature tag is marked the more the status and notoriety of the

writer grows. In the context of gang graffiti Ley and Cybriwsky (1974) claim that

establishing the territory generates security, and maintaining or embellishing it

guarantees status. While the competing tags in the Surry Hills area are not those

of competing gangs (the gang graffiti present in US cities is not a feature of

Sydney graffiti – see Iveson 2007), the behavioural geography associated with

this type of territorial competition for status and wall space is certainly evident.

Putting these observations together with the more generic data provided by the

City of Sydney, we can observe that the more elaborate and artistic forms of

graffiti are not to be found on the streets identified by Council as removal priority

zones. Graffiti management priority zones like Crown Street tend to be

dominated by tags. This lends some weight to claims that rapid removal may

result in changing forms as well as changing locations of graffiti (Iveson 2009),

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pushing graffiti writers into quicker styles in areas likely to be highly surveilled

and regulated.

4. Concluding Reflections

While the mapped distributions of graffiti provide insight into the patterns of

graffiti occurrence, alone they are limited in informing of the cause of processes

behind these patterns. The behavioural environment associated with graffiti

culture, the local social processes surrounding the diversity of graffiti occurrence,

and the impacts of different forms of graffiti (and its removal) on local

communities must also be understood.

The City of Sydney is an example of the dominant approach to the regulation of

graffiti – it employs rapid removal strategies to deter graffiti on the grounds that it

is a form of anti-social behaviour that has a harmful impact on neighbourhood

character and quality of life (City of Sydney 2004). In this article, we have sought

to deploy GIS methods in order to contribute to debates about the politics and

effectiveness of this approach to graffiti management. Our analysis was informed

by claims that this dominant approach to graffiti management is premised on an

ideological positioning of all forms of graffiti as intolerable (Moreau and Alderman

2011), that it neglects the positive contribution some forms of graffiti might make

to urban character and communities (Dovey et al 2012), and that it has a series

of perverse effects by changing the form and location of graffiti (Iveson 2009),

Through an analysis of both graffiti removal data and our own data about graffiti

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incidences in a local ‘hot spot’, we have found that there is indeed evidence to

support claims that rapid removal does not deter graffiti so much as shift its

location and its form. We have also found evidence of a diversity of graffiti types

at a local level. In light of this, we argue that different regions within the LGA

may benefit from alternative management approaches. Addressing this diversity

will create the opportunity to develop policies that retain the dynamic, economic

and culturally invigorating aspects of graffiti whilst reducing aspects that impact

negatively on the community and the writers themselves (Halsey & Young, 2002).

Combined with qualitative research into community attitudes to different forms of

graffiti, mapping the spatio-temporal diversity of graffiti occurrence could actually

facilitate site specific graffiti management. Understanding the changing spatial

and temporal outcomes of various strategies employed could lead to the

formulation of better-informed initiatives. Current limitations of existing

approaches could become their strength, by changing the form and location of

graffiti to something more desirable for all acting groups (Iveson, 2009).

There are some limitations in our findings. Graffiti removal records provide a

useful surrogate for graffiti occurrence in the absence of resource intensive field

surveys. However, despite the strict zero-tolerance policy it is likely that graffiti

presence is underrepresented in these removal data. Between February and

July 2010 there were 186 graffiti removal incidents in the two Surry Hills study

areas which is less than the number recorded during the field survey. It was not

possible to access graffiti removal data coincident with the field survey and

further work is required to examine the reliability of removal records as an

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indicator of graffiti presence.

Limitations in the graffiti removal dataset have consequences for subsequent

analysis. Whilst the proportion of successfully geocoded graffiti removal

incidents was sufficient for the purpose and scope of this study, limitations

associated with the sub sample of data available for analysis should be

considered. Approximately 64% of entries within the City of Sydney graffiti

removal data record did not include full address details resulting in their exclusion

from the analyses and under representation of graffiti on smaller less static

structures. In addition, errors in the graffiti removal datasets limited geocoding

match rates. A more comprehensive dataset of graffiti removal locations could be

obtained using GPS to provide explicit locational reference for graffiti incidents on

all structures and surface types.

A more detailed study involving qualitative methods including community

interviews and surveys within hotspot areas may reveal characteristics of the

area, of graffiti culture, or of the removal effort that may be contributing to the

trends observed. The City of Sydney graffiti removal data does not afford a full

representation of all aspects of graffiti occurrence and removal, as it does not

capture the diversity associated with graffiti occurrence including graffiti type,

form, media, surface, property type, and content. This contextual information is

needed to examine graffiti occurrence as an urban phenomenon and understand

graffiti culture more broadly. Its absence in the graffiti removal records presented

a limitation in the study. Although graffiti incident records collated by graffiti

removal contractors provide a valuable source of occurrence data at high spatio-

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temporal resolution, due to the operational focus they are unlikely to include data

relating to graffiti form. This issue was addressed through local scale mapping of

the Surry Hills hotspot which demonstrated graffiti diversity within a small area.

Spatio-temporal analysis of graffiti writing and removal practices within an urban

landscape may be used to inform the development of new policies that better-

accommodate the desires of different stakeholders, including the council, local

authorities, transport agencies, town planners, local businesses, the creative and

artistic industries, community members, and the graffiti writers themselves. The

study findings highlight the diversity and spatio-temporal variability of graffiti as a

phenomenon within the city. Graffiti occurrence and removal data could be

analysed further with additional spatial layers to observe correlations with other

characteristics of the urban environment, including physical street layout,

composition of land uses (such as residential, retail and light-industrial),

residential demographics and publicly accessible open space. This information

could be utilised to aid in identifying potential space for ‘legal’ graffiti, by defining

areas that are plagued by high graffiti occurrences, or areas where graffiti is

‘preferable’, as defined by dialogue between representatives of various interest

groups. These methods may foster dialogue through interactive maps that depict

the dynamic nature of graffiti space, whereby different desires based upon this

information can be weighted and tested through spatial modelling. Further to the

visualisation of graffiti incidences, the spatial preferences of different players, as

well as zoning and planning options for various strategies could be modelled.

Data accuracy and broader accessibility to the technology are important factors

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in the applicability of these forms of analysis, and while mapping the spatio-

temporal trends of graffiti removal establishes pattern, further qualitative analysis

is required to infer process and explore alternative forms of spatial knowledge. It

is thus advocated here that an integrated approach, incorporating quantitative

GIS analysis and spatial modelling with existing qualitative methods, be adopted

for both further research and policy development.

Acknowledgements

The authors wish to acknowledge John Mousely and the City of Sydney Council

for providing the graffiti incident data and graffiti policy information. Thanks are

also given to Amanda Tatzenko for her assistance in undertaking the field

component of this study.

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