The impact of Melbourne’s growth on
‘seasonal herbaceous wetlands (freshwater)
of the temperate lowland plains’
Melbourne Strategic Assessment
Department of Environment and Primary Industries
Published by the Victorian Government Department of Environment and Primary Industries
Melbourne, May 2013
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Department of Environment and Primary Industries
Contents
Introduction
2
Background
Scope
2
2
Delineation of the ecological community
3
Evaluation of existing spatial data
4
Time-stamping
Wetlands 1994
EVC 2005 and NV2005_EXTENT
Index of Wetland Condition (IWC) Project
Aerial imagery
Historic map resources
4
4
5
5
5
6
Integration and use of spatial data
7
Assessing SHW across the Melbourne region
Assessing SHW across Victoria
Identifying sites outside the Melbourne SIA area for protection
7
8
8
Targeted assessment of larger potential SHW sites
9
Western Growth Corridor
Northern Growth Corridor
Western Grassland Reserve
South East Growth Corridor
9
16
21
27
Results: spatial assessment of impact
28
SHW impacts across the Melbourne SIA region
SHW impacts across Victoria
31
31
Prospects for protection and management
32
Wetlands: dynamic ecological character
Wetlands: Impacts
Wetlands: condition of sites
Prospects for management and restoration
Candidate sites outside Melbourne for future protection
32
32
34
36
37
Limitations
38
References
39
Appendix 1: Locations of assessed sites.
40
Introduction
Background
The expansion of Melbourne’s Urban Growth Boundary (UGB) will impact several ‘matters of national environmental
significance’ listed under the federal Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). A
Strategic Impact Assessment (SIA) conducted by the Victorian Government (DPCD 2009) recommended ways of
mitigating potential environmental losses. The mitigation measures agreed to by the Victorian and Australian
governments are outlined in the Program Report (DSE 2009) and the Biodiversity Conservation Strategy (DEPI 2013).
Since the finalisation of the Program Report, a new ecological community was listed under the EPBC Act: Seasonal
Herbaceous Wetlands (Freshwater) of the Temperate Lowland Plains’ (hereafter SHW, listed in 2012). SHW were not
considered in the SIA, and the impact of the UGB expansion on the community has not yet been assessed.
Scope
This report provides an assessment of the spatial impact to SHW. It is largely a desk-top analysis, with some limited field
verification.
This report will address the following issues:

The area of SHW that will be lost to development around Melbourne, and the area that will be protected in the
proposed conservation areas (Western Grassland Reserve (WGR) and Conservation Areas in the BCS, DEPI
2013)

How impacted SHW will be offset under ‘Time-stamping’ (see DSE 2009)

The relative magnitude of SHW loss around Melbourne, in a statewide context

Potential sites for the protection of SHW across Victoria
This report also briefly discusses the condition of SHWs in the Melbourne area, and the prospects for protection and
management in the urban context.
Impact and protection
This report assesses ‘impact’ only in terms of ‘area lost’. It does not explicitly consider functional or ecological impacts
such as hydrological changes or the viability of native species populations, although these are discussed briefly in
section 7 (Prospects for Protection and Management).
Areas are considered ‘protected’ only if they are located within an existing Nature Conservation reserve (NCR), within the
WGR or within a designated Conservation Area (CA) in the Biodiversity Conservation Strategy (BCS; DEPI 2013). Areas
that may afford some lower level of incidental ‘protection’ are not considered ‘protected’ in this report (e.g. Urban Flood
Zone, Rural Conservation Zone). Areas not protected are considered either ‘lost and offset’, if they are captured as
native vegetation (of any sort) in ‘Time-stamping’; or ‘lost’ altogether if they are unprotected and not covered by Timestamping.
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Delineation of the ecological community
The SHW community is described in detail in the ‘listing advice’ for this community (TSSC; 2012), and that description
has been followed closely here when assessing whether sites are SHW. The following points are, however, worth
emphasising, as they emerged as important factors when making site-by-site determinations:

Riparian areas and creek-lines are generally excluded from SHW. The listing advice states that SHWs occur on
depressions that are “…isolated, closed or endorheic systems… Inundation is not dependent on connections to
riverine systems (TSSC 2012; p2 & p10).” This distinction is not obvious in some systems, where creeks drain
into or emerge from extensive wet flats (e.g. Hearnes Swamp, wetland 20). Wetland areas that are
hydrologically connected to rivers or creek-lines were included here only if they included significant areas
capable of holding shallow standing water. Defined channels within or adjacent to such areas were excluded

SHW are not woody wetlands (woody cover less than10 per cent, TSSC 2012; p10). This was interpreted so
that portions of wetlands could be included where they were open, and other areas of the same wetland
excluded where they were wooded. Muehlenbeckia florulenta was interpreted as a woody species.

SHW are not dominated by ‘taller native graminoids’ which form species-poor stands (TSSC 2012; p7; notably
Eragrostis infecunda or Phragmites australis). Some wetlands were divided, leaving portions assigned to SHW,
and other portions excluded on the basis of their species composition.

Wetlands with a substantial cover of Eleocharis acuta were difficult to classify. This species is very common,
and its treatment is important. The genus Eleocharis is listed among the ‘taller native graminoids’(above) where
over-dominance indicates SHW is not present. Eleocharis acuta may occur in both very dense single species
stands (not SHW) and at a range of covers in more or less diverse wetlands (some SHW). Eleocharis acuta
seems to survive cropping better than many other SHW species, and grows back with particular vigour after
prolonged drought (often with Marselia drumondii), as observed in 2011-2012 after a drought of many years.
Several wetlands previously reported to be grassy and herb-rich (and thus SHW; Schulz et al 1991) were found
to be now covered largely by Eleocharis acuta, with a few scattered herbs and grasses consistent with SHW. It
is considered that dominance by this species may represent degradation of other SHW communities after
cropping; it may be ‘natural’; or it may be a temporary response of SHW to recent drought breaking rains.
Given this variability in cover and site history, Eleocharis acuta was treated with caution. Here, if Eleocharis
actuta occurred and grasses and some herbs remained present, a wetland was considered SHW, even if the
cover exceeded 25 per cent. Figure 12 illustrates this situation in Richmonds Grass Swamp.

SHW were considered not to occur in sandy areas known to formerly support wet heaths or ‘Tea-tree swamps’,
regardless of their current status. It is acknowledged that SHW may include sites which were once woody, and
have subsequently been cleared however, it is also noted that SHW occur on “generally fertile but poorly
draining clays” (TSSC 2012 pp2&9). This consideration is only relevant in the south east of Melbourne.

Continual cropping will remove SHW (TSSC 2012), however recent observations around Melbourne indicate the
community survives occasional cropping. Observation suggest that some SHW species survive cropping better
than others, and may increase in cover after cropping (e.g. Eleocharis acuta and Marselia species seem
particularly resilient, while Poa labillardierei and many herbs seem to be very sensitive). It is thus difficult to
apply cropping history as a definitive filter which allows or precludes SHW. In order to make a best estimate of
SHW, the following principles were applied:
– If an area could be observed, the vegetation was assessed regardless of cropping history
– If aerial photographs were being used, relatively small areas (less than 3 ha) which are regularly cropped
were excluded from further analysis
– If aerial photographs were being used, larger wetlands or wetlands with previous data suggesting they
retained biological values were retained in the initial dataset regardless of cropping history (e.g. Ballan Rd
Wetland), and investigated further.
There are hundreds of small depressions (mostly less than 0.1ha) around Chartwell and Tarneit in regularly cropped
areas which were excluded with the application of these rules.
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Evaluation of existing spatial data
Introduction
Several existing datasets contain information which is useful for mapping SHW. However, none of those datasets were
created after the definition of SHW and none specifically delineate the community. This section evaluates those datasets
for use in assessing SHW. This section only considers existing datasets and not datasets that could potentially be
produced.
Time-stamping
The Time-stamping dataset is a freely available polygon dataset held by the Department of Environment and Primary
Indutries (DEPI). It captured and ‘time stamped’ native vegetation information. It represents vegetation type (according
to Ecological Vegetation Class (EVC)), and vegetation condition according to habitat hectares (DSE 2004). It was
created from two distinct sources:

Field assessments done by a range of consultants between 2008 and 2012.

Modelled data (see NV2005_EXTENT, below).
Time-stamping is considered the definitive vegetation dataset for the Melbourne SIA area.
Time-stamping is a reasonable dataset to use because clearly delineated portions of the dataset were created from
detailed field assessments using standard techniques and a quality assurance process and the data were captured
recently.
However, as the dataset was created before SHW was listed, it does not deal comprehensively with this community. The
limitations of this dataset with respect to SHW are noted below:

Only the site-based data is reliable enough to properly represent SHW. The modelled data are often unable to
capture dynamic wetland systems.

Some site assessments were done during drought, and default scores were applied to wetlands. The status of
those sites as SHW is therefore unconfirmed.

The EVCs used in Time-stamping do not align exactly with SHW. Areas mapped as Plains Grassy Wetland and
Plains Rushy Wetland in Time-stamping are considered to correspond to SHW, however other wetland EVCs
may or may not be SHW (e.g. Aquatic Herbland). Drier forms of SHW are very similar to Plains grassland and
may reasonably be mapped as Plains Grassland (when Poa labillardierei or Rytidosperma duttonianumdominated).

SHW patches may be very small, and may have been captured within other native vegetation patches.

The condition thresholds for SHW and native vegetation in Time-stamping differ. This means that in some
patches Time-stamping is may have over-estimated the condition or extent of SHW

Time-stamping does not cover the Western Grassland Reserves, making it incomplete for an assessment of all
areas of SHW protected under the program. The GAA surveys that preceded the final UGB determination (GAA
2010), however, did cover some of the WGR, and are treated in the same way as Time-Stamping.
Wetlands 1994
Wetlands 1994 is a freely available polygon datasets held by DEPI. It shows the extent of all wetlands larger than 1ha
across Victoria as determined in 1994. These are categorised using the system of Corrick and Norman (1980). Two
categories correspond closely to SHW:

Freshwater Meadow (Herbaceous; category 2.01). These include shallow (up to 0.3 m) and temporary (less
than four months duration) surface water, although soils are generally waterlogged throughout winter, with
herbaceous (non-woody vegetation),

Shallow Freshwater Marsh (Herbaceous; category 3.01). Wetlands that are usually dry by mid-summer and fill
again with the onset of winter rains. Soils are waterlogged throughout the year and surface water up to 0.5 m
deep may be present for as long as eight months, with herbaceous vegetation.
The dataset is useful because it has state-wide coverage, and is unbiased with respect to the SIA area.
The limitations of this dataset with respect to SHW are noted below:
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
It only recognises wetlands larger than 1ha. Patches of SHW are frequently smaller than this. It is therefore
possible that the dataset does not accurately represent the coverage of SHW as quite a large proportion of the
state-wide area of SHW is in small patches.

It does not distinguish areas which support native vegetation from those which do not, and hence it is likely to
greatly over-state the coverage of SHW.

It has not been reviewed since it was established in 1994 (19 years ago).

Although its classification scheme matches SHW fairly well, some wetlands which are not SHW may be
included (e.g. dune swale or limestone wetlands).
EVC 2005 and NV2005_EXTENT
NV2005_EXTENT is a modelled dataset owned by DEPI that describes the extent of native vegetation across Victoria. It
categorises grid cells (25m2) into eight categories ranging from 'highly likely native vegetation' through to 'unlikely to
support native not, possibly, highly likely). It has been created from time-series (1989-2005) Landsat Imagery, many
thousands of field-based training points, other relevant spatial data and expert validationand forms the basis of other
native vegetation products.
EVC 2005 is a freely available polygon (or grid) dataset held by DEPI, that shows the distribution of vegetation types
(EVCs) across Victoria. EVCs are only assigned to areas of (likely) native vegetation according to NV2005_EXTENT.
The EVCs have been assigned regionally, based on previous mapping studies, and use a range of approaches.
Although numerous EVCs are likely to correspond to SHW (TSSC 2012), the EVC 2005 dataset actually only includes
two relevant classes (Plains Grassy Wetland and Plains Sedgy Wetland). Other examples of SHW are mostly included
in the default category ‘Wetland formation’.
The dataset is useful because it has state-wide coverage, and is unbiased with respect to the SIA area.
The limitations of the EVC 2005 and NV2005_EXTENT datasets with respect to SHW are noted below:

The 25m grid cell resolution means that smaller patches of SHW are not captured, however wetlands smaller
than 1ha are included, so it has better resolution than the Wetlands 1994 dataset.

The EVCs do not align perfectly with SHW. Many wetland areas are assigned a default wetland category
(“Wetland formation”) which does not allow a determination of their type to be made.

The EVCs have been assigned by different observers using different techniques in different places, so that the
dataset is not consistent across Victoria.

Much of the dataset is modelled and may be incorrect at specific locations.
Index of Wetland Condition (IWC) Project
The IWC project assessed the type and condition of approximately 900 selected wetlands across Victoria. The study
focussed on wetlands thought to be of high significance. It included all Ramsar sites; numerous non-riverine wetlands
contained in 29 sites listed in the Directory of Important Wetlands Australia (DIWA) (Environment Australia 2001), and
the ‘Edenhope wetland complex’ in the Wimmera region of Victoria. The IWC database uses the Wetlands 1994 layer as
its spatial reference. The database is held by DEPI.
This dataset is useful because it is based on recent ground assessments and it provides data on the condition of
wetlands, not just their location.
This dataset has the following limitations with respect to SHW:

It provides a snapshot of selected wetlands; it does not provide complete coverage of Victoria.

Like the Wetlands 1994 dataset this dataset also recognises wetlands that are larger than one ha. As patches
of SHW are frequently smaller than this it is possible that much of the state-wide area of SHW is missing or
under-represented.
Aerial imagery
Aerial imagery is available for the state, from a range of different recent seasons and years.
SHW may best be recognised with reference to multiple images, taken in different seasons. In the SIA area, SHW may
be identified from the following:

Visible-spectrum and infra-red images from summer 2008-2009 captured a landscape carrying low biomass
following drought, making soil colours visible (SHW are usually greyish).
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
Visible-spectrum imagery from 2011 showed wetlands holding water.
Informal field checks undertaken by DEPI suggests that this technique is accurate in detecting SHW in areas where trees
were never present (e.g. some places west of Melbourne), however, it cannot reliably detect SHW in areas where woody
wetlands have been cleared (e.g. south east of Melbourne).

Aerial imagery is useful becauseit can detect SHW at any scale, and allows the correct size thresholds to be
applied. Further woody cover can be estimated or measured accurately. It is also recent and its coverage is
consistent.
Aerial imagery has the following limitations with respect to SHW:

It requires additional subjective interpretation, which can be very difficult.

It cannot be used to detect species composition.
Historic map resources
In the nineteenth century, parish plans (and other maps) often included comments about vegetation and landforms.
These were generally included to describe the land to potential settlers. There are a number of plans available that
cover the SIA area, however these are considered important only for the south eastern area. Cook and Yugovic (2003)
and Yugovic and Mitchell (2006) offer some interpretation of the historic plans.
Historic plans are useful as they sometimes allow a view of wetland ‘type’ before many of the changes that have
subsequently occurred. For example, they may help us resolve whether wetlands were ‘naturally’ woody or not.
Historic plans have the following limitations with respect to SHW:

Their coverage is incomplete, and their spatial accuracy is variable.

Their descriptions of vegetation are subjective, possibly biased by political and social factors, and cannot be
independently verified.
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Integration and use of spatial data
Introduction
This section describes how the datasets above were used to assess the impact of Melbourne’s growth on SHW. In order
to avoid or minimise the limitations of each dataset, the data have been combined as follows:

The Time-stamping data used in combination with new aerial photograph interpretation and cross-checking with
field-based observations is considered best for the Melbourne growth areas. A combined dataset has been
produced to assess impacts in the Melbourne SIA area. Historic plans have been used to discount SHW from
some of the south eastern area.

DEPI’s EVC 2005 dataset or DEPI Wetland 1994 dataset in combination with NV2005_EXTENT is considered
appropriate for a statewide assessment.
Assessing SHW across the Melbourne region
In order to assess SHW in the Melbourne SIA region, the Time-stamping data were combined with new aerial photo
interpretation (API) and field observation.
First, a series of aerial photographs was used to identify possible SHW patches within the Melbourne SIA area. As
described above, soil cover and context (discontinuity with rivers or creek-lines) were used to guide this assessment.
This dataset did not detect any likely SHW in the SE growth corridor. This interpretation was done without reference to
the Time-stamping data.
The south east growth corridor is difficult to treat using aerial photographs. The area is geomorphologically variable
(sandstones, clays, sands), and potentially contains visible wetlands that are not referrable to SHW (e.g. Woody or
formerly woody ‘Swamp Scrub’ wetlands; wetlands on infertile sites dominated by sedges). Furthermore, the soil
colouration that is a reliable indicator of wetlands on the volcanic plain (north and west of Melbourne) does not appear to
apply in the south east. Understanding of these areas has increased greatly in recent years following detailed studies
based on historic parish plans and detailed field investigation (Cook and Yugovic 2003, Yugovic and Mitchell 2006).
Examination of these studies and the original parish plans (Foot 1857, Callanan 1859) confirm almost all wet areas in the
south eastern growth corridor were originally tea tree scrub or plains of heath. These systems are not consistent with
SHW. The exceptions are the far south east and east portions of the study area, where there is good evidence of former
open, grassy, wet plains (Yugovic and Mitchell 2006). The aerial photograph interpretation did not reveal any possible
SHW in the south eastern growth corridor (however see below, under ‘Targeted Assessments’).
This data were then combined with the Time-stamping data to produce a new ‘layer’, which is the best available
delineation of SHW. The following process was used:

Areas of SHW identified from the imagery that were surveyed in the field for Time-stamping and assessed as
‘non-native vegetation’ were deleted. (One large patch NW of Tarneit Rd and Leakes Rd in Tarneit was
excluded on this basis, following two assessments, in wet and dry phases).

Areas mapped as Plains Grassy Wetland or Plains Sedgy Wetland in Time-stamping were added (even if not
picked up in the aerial photograph survey).

The data were reviewed, with every patch larger than 3 ha assessed individually for inclusion (described in
detail below in section 5 ( ‘Targeted Assessment of larger potential SHW sites’).

To implement the size and aggregation rules (TSSC 2012), the dataset was converted into a grid-based dataset
with 5m pixels (1= SHW, 0= not SHW). For each pixel, the sum of all pixels within a 25 pixel radius was
calculated (~125m radius approx. 5 ha area neighbourhood). All pixels with a sum value of greater than 200
(each cell is 0.0025 ha, 200 cells are 0.5 ha) were considered to reside within a wetland cluster (i.e. consistent
with TSSC 2012). Any wetland polygon less than 0.5 ha in size was retained if it included such a pixel, and
deleted if it included none (all polygons greater than 0.5 ha meet the size thresholds in their own right). The
adjacency rule was applied by reinstating all deleted polygons greater than 0.1 ha which intersected any patch
of remnant patch in the Time-stamping dataset that was greater than 0.9 ha (total 1 ha). Minor modifications to
the GIS layer made as a result of the site assessments were done after this analysis was performed however
they were to polygons that were not near the critical thresholds for implementing the size criteria.
Once this dataset was produced it was subject to field testing (see section 5 ‘Targeted Assessment of larger potential
SHW sites’).
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Assessing SHW across Victoria
The Wetland 1994 datset provides a consistent view of larger wetlands across Victoria however it does not adequately
distinguish native from non-native vegetation. In order to include only those areas likely to retain sufficient native
vegetation to qualify as SHW, DEPI’s modelled NV2005_EXTENT data were used to refine the Wetland 1994 dataset.
NV2005_EXTENT categorises the landscape into eight categories ranging from 'highly likely native vegetation' through to
'unlikely to support native vegetation'. For the purposes of this report, areas in Wetland 1994 were considered to contain
SHW if they were also considered in NV2005_EXTENT to be:

wetland habitat

highly likely native vegetation - grassy, or

highly likely native vegetation – structurally modified.
Identifying sites outside the Melbourne SIA area for protection
The process of identifying sites outside the Melbourne SIA area is preliminary and not exhaustive.
The IWC dataset was filtered to selected sites that met the following criteria:

More than 20 per cent of the site was covered by an EVC relevant to SHW (see above)

The overall condition was’good’ or ’excellent’

The Biota component score was ’good’ or ’excellent’

The total wetland size was greater than 20ha (not necessarily all SHW)

On private land.
Corangamite and Glenelg Hopkins Catchement Management Authority (CMA) staff were also invited to nominate sites.
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Targeted assessment of larger potential SHW sites
Introduction
All areas of potential SHW that were larger than 3ha were investigated to determine whether they should be designated
SHW. The larger sites were targeted because an incorrect determination would contribute to large errors in the area
calculations. Areas were included regardless of whether they were protected or not. There are no sites larger than 3 ha
in the north western (Sunbury) growth corridor.
The assessment involved a combination of field checks and reference to existing literature. The results of this
investigation are summarised below. The wetlands are listed in order of size (before review), by growth corridor.
Wetland names are taken from Schulz et al (1991) where available. Other wetlands have been assigned names for use
in this report (See Appendix 2). Of 48 sites larger than 3ha, 20 were observed by DEPI. Many more were able to be
assessed using existing data. Others could not be accessed in the available time.
Each wetland assessment is summarised in a table, which shows the following information:

EC type? Does the wetland conform ecologically to the description of the Ecologicaly Community (EC)?

EC Condition? Does the wetland currently meet the condition thresholds for the community?

Outcome: summarises what changes (if any) have been made to the preliminary dataset described in section
4.2 (‘Assessing SHW across the Melbourne region’).

Area of SHW: summarises the area of SHW retained in the final SHW dataset following review. Wetlands must
be assigned a ‘Yes’ to both ‘EC type’ and ‘EC condition’ to be retained in the dataset. Some wetlands are
partially retained, such that their area in the final dataset (described in section 6, ‘results’) is reduced from their
area in the preliminary dataset (section 4.2).
During the course of the literature checks and the field work, several new wetland areas not included in the preliminary
dataset were identified (notably through the work of Cook et al 2013). These were added to the final dataset.
Following this assessment, the SHW dataset described above (combined Time-stamping and API) was amended. The
resulting dataset was used in subsequent sections to provide maps and area calculations. The locations of the wetlands
assessed for inclusion in the final SHW dataset is included in Appendix 1. The final SHW dataset is presented and
discussed in section 6 (Results)
Western Growth Corridor
1. Ballan Road wetland (unprotected, Urban Growth Zone)
This wetland was assessed as part of the Time Stamping project when it was devoid of vegetation. It was designated as
‘Plains Grassy Wetland’ and a default site score was assigned. No other site data are known (it was not included in
McDougall 1987 or Schulz et al 1991). Aerial photographs show that the wetland is traversed by an artificial drainage
channel. It is also apparent that the entire wetland has been ploughed in the past although many past plough lines avoid
the wetland (hence this large site was not automatically excluded on the basis of ploughing).
The site was visited on 1 August 2012. The site had been recently grazed by cattle (Figure 1). The most abundant native
species were Eleocharis acuta, Juncus spp. and Amphibromus sp. Several native herbs were present at very low cover
(Dichondra repens, Lythrum hyssopifolia, Montia australasica, Ranunculus sp.). This species composition is consistent
with SHW.
The total cover of all native vegetation across the wetland was approximately5-10per cent, and in no sizeable patch did it
exceed 20per cent. The remainder of the wetland was covered by introduced species common in pastures (Lolium sp.,
Helminthotheca echioides and an unknown immature Brassicaceae were most prominent). The coverage of native
species was not high enough to meet the basic condition thresholds for the community, and this wetland was not
assessed as SHW.
Ecological Community (EC) type?
Yes
Ecological Community condition?
No
Outcome:
Removed from SHW layer.
Area of SHW:
None
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Figure 1. Ballan Road wetland at Wyndham Vale determined not to be SHW.
2. Deanside West Wetland (partially protected)
This site was assed by McDougall (1987) and Schulz et al (1991), and again by Biosis Research as part of the Timestamping project. Gilmore (2011) nominated it as an important site. The wetland area has been partly and irregularly
ploughed in the past (ploughed prior to 2006, again in 2008-09).
The area consists of two linked swamps. The western swamp is usually wet and brackish, while the eastern swamp is
more ephemeral. The species lists in McDougall (1987) and Schulz et al (1991) suggest that the wetlands are SHW (not
too brackish, not generally woody). However, as the western wetland is referred to as ‘permanent’ by these studies, and
aerial photographs showed that much of it still held water in January 2009 (after prolonged severe drought); most of the
western wetland could not be considered SHW due to its hydrology (TSSC 2012).
EC type?
west partially; east yes
EC condition?
Assumed yes, but has been partly ploughed
Outcome:
Removed portion of western wetland from SHW; retained eastern wetland
Area of SHW:
Approximately18 ha
3. Troups Road Swamp (unprotected, Urban Growth Zone and Urban Flood Zone)
This swamp is divided by Troups Rd North and the railway line and spans multiple parcels. Several investigations have
been made of this wetland over many years. Schulz et al (1991) provide a species list and hydrological description that
suggest that the majority of the swamp is naturally referrable to SHW, excluding the band of dense Muehlenbeckia
florulenta around the margin. The SHW section has been partly cropped in the past. The western section has been
ploughed most years since 2004, apart from a few consistently undisturbed areas. The far eastern parcel does not
appear to have ever been ploughed (no evidence in any photograph from 2004-2013), while the mid-eastern portion
(east of the road) was ploughed in 2004 and 2012.
The site was visited by DEPI on 13 August 2012, and viewed from the road and rail side. This assessment confirmed the
recent cropping noted above, with the cropped areas being dominated by annual pasture weeds. It also confirmed that
the far eastern section was strongly dominated by native species (greater than 75per cent cover see Figure 2) and was
therefore SHW (prominent species included Eleocharis acuta, Lachnagrostis filiformis, Lythrum hyssopifolia, Centipeda
cunninghamii, Asperula conferta., Epilobium billardierianum).
In March 2013, Cook et al (2013) visited this site and assigned the whole site to SHW apart from the areas dominated by
Muehlenbeckia. Their assessment was done after an extremely dry summer, when the annuals evident in August 2012
had died off, and only a few hardy native perennials that had survived the soil disturbance persisted (Cook et al 2013).
EC type?
Yes excluding woody margins
EC condition?
Eastern - most property clearly SHW, remainder marginal
Outcome:
Retain most of wetland in SHW dataset (except for regularly ploughed areas)
Area of SHW:
Approximately 8 ha
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Figure 2. The portion of Troups Rd North Swamp designated as SHW (Lythrum hyssopifolia, Eleocharis acuta (desiccated and inactive) and
Asperula sp. dominate in this view).
4. Rockbank Railway Swamp (unprotected, Urban Growth Zone)
There is doubt as to whether this wetland is naturally an example of SHW or a degraded woody wetland. The wetland
was described by Schulz et al (1991) as a “Shallow freshwater marsh with a few River Red Gums and scattered Tangled
Lignum” that had been ploughed with the result that Lignum (i.e. a woody species) was reduced in cover. This wetland
was also assessed under the Time-stamping project and found to be native vegetation (weed cover less than 25 per
cent) and assigned to the EVC ‘Lignum Swamp’ an EVC not generally consistent with SHW. Current aerial photographs
show almost no woody cover and no evidence of regular recent ploughing. Taken together, these data suggest that the
wetland currently qualifies as SHW but it may once have been too woody to meet the criteria.
EC type?
Yes but a peripheral or derived example (woody elements)
EC condition?
Yes
Outcome:
Retained in SHW dataset
Area of SHW:
Approximately 9 ha
5. Paynes Road Swamp (unprotected, Urban Growth Zone)
This wetland was surveyed by McDougall (1987), Schulz et al (1991) and Cook et al (2013). The describe it as a Lignum
wetland with a grassy and herbaceous understorey. It was not assessed in the field as part of Time-stamping, although
the DEPI EVC data categorise it as native vegetation assignable to the EVC ‘Lignum Swamp’. However, recent aerial
images show that the cover of woody species is between 5 and10 per cent which is within the acceptable range for
SHW. The section east of Paynes Road (within SIA area) clearly met the condition criteria for SHW. It was dominated
by Poa labillardierei, under a sparse layer of Muehlenbeckia florulenta (except for one area in the south east which was
dominated by perennial introduced grasses and is no longer SHW). The section west of Paynes Road is outside the SIA
area.
EC type?
Yes but marginal in places (woody elements)
EC condition?
Yes with some small exclusions
Outcome:
Retained in SHW dataset with some minor modifications
Area of SHW:
Approximately 4.7 ha (Approximately 7 ha including areas outside UGB)
Figure 3. The eastern portion of Paynes Rd Swamp . Poa labillardierei is the dominant ground-layer species. Muehlenbeckia florulenta is
present at levels just within the bounds of SHW.
6. Wyndham Vale Swamp (unprotected, Urban Growth Zone)
This site was described in Schulz et al (1991), when it was heavily grazed and damaged by hoof marks (pugged). It was
assessed again as part of the Time Stamping project as native vegetation (weeds greater than 50 per cent) referrable to
‘Aquatic Herbland’ an EVC not always associated with SHW (TSSC 2012), but likely to be consistent in this context (on
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the Werribee plains, after high rainfall). This information was considered sufficient to retain the wetland in the SHW
dataset.
EC type?
Yes
EC condition?
Yes, probably, although cropped in the past
Outcome:
Retained in SHW dataset
Area of SHW:
Aproximately 6.2ha (Approximately 16 ha including areas outside UGB)
7. Chartwell Wetland No.1 (North East of Troups Road South / Middle Road) (protected)
This site was field surveyed as part of Time-stamping and assigned to ‘Plains Grassland’ vegetation. The aerial
photographs indicated patches of very pale soil, consistent with other known patches of SHW. Previous field inspection
by DEPI in 2008 of one drier edge of this site that crosses a road reserve suggested that SHW exists in these pale-soil
depressions although it is at the drier end of the community (i.e. it contains Themeda triandra, Cullen parvum, etc).
EC type?
Yes, but drier margins of SHW
EC condition?
Yes
Outcome:
Retained in SHW dataset
Area of SHW:
Approximately 10 ha (in two main patches)
8. Deanside East Wetland (unprotected, Urban Growth Zone)
This area is part of the Deanside complex described above (Deanside West). This discrete section was nominated by
Gilmore (2011) as an important site. It was described as ‘Plains Grassy Wetland’ with abundant native vegetation. The
Time-stamping field surveys found that parts of the wetland were not native vegetation, making only a portion of the
wetland potentially referrable to SHW. This wetland was viewed from the road on 13 August 2012. Portions of the
wetland are heavily grazed and appear to contain only pasture grasses. Other areas contain vegetation dominated by
Poa labillardierei, with a layer of Muehlenbeckia florulenta at densities just low enough for inclusion in SHW. Cook et al
(2013) assign more of the wetland complex to SHW (and native vegetation) than Time-stamping does. This report
follows Time-stamping.
EC type?
Yes but marginal (woody elements)
EC condition?
Patchy
Outcome
Divided wetland into sections for deletion or inclusion in SHW dataset based on Time Stamping.
Area of SHW:
Approximately 8 ha
9. Paynes Road North Wetland (unprotected, Urban Growth Zone)
This wetland was not described in the early reports of McDougall (1987) nor Schulz et al (1991) It was assessed as
SHW by Cook et al (2013), after an extremely dry phase. Aerial images indicate it has been ploughed regularly since at
least 2000. It was inspected by DEPI during a relatively wet period from the roadside on 13 August 2012 and was found
to contain almost exclusively introduced pasture species and a fringe of Muehlenbeckia florulenta (Figure 4). It was
concluded that Cook et al (2013) were unable to discern the weed levels when they visited in 2013 and that the true
character of the site was best revealed in 2012. The site was not considered SHW.
EC type
Probably, but marginal (woody elements in uncropped areas)
EC condition
No
Outcome
Delete from SHW dataset
Area of SHW
None
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Figure 4. Paynes Rd North Wetland determined not to be SHW.
10. Kororoit Creek Wetland No. 1 (unprotected, Urban Growth Zone)
Little information was available on this wetland. It has been cropped in the past, and was assessed by Cook et al (2013)
as being not SHW. On this basis, it has been excluded here.
EC type?
Uncertain, probably
EC condition?
Assessed as not SHW in 2013
Outcome
Delete from SHW dataset
Area of SHW
None
11. Rockbank Wetland (unprotected, Urban Growth Zone)
No information was available on this wetland, and it could not be accessed. It has been cropped in the recent past and is
surrounded by a few River Red Gums.
EC type?
Uncertain, probably
EC condition?
Unknown, probably low
Outcome
Retain in SHW dataset
Area of SHW:
Approximately 4 ha
12. Kororoit Creek Wetland No. 2 (protected)
This area was visited by the DEPI on 5 August 2011 as part of a Time-stamping data audit. The area contains two
nearby wetlands. Although the wetlands contains woody elements (Muehlenbeckia florulenta) these are of sufficiently
low cover to permit classification as SHW. The condition of the wetlands is excellent with very few weeds. This area
was also assessed by Cook et al (2013), and was again confirmed as being high quality SHW.
EC type?
Yes
EC condition?
Yes
Outcome:
retain in SHW dataset (5.7 ha)
Area of SHW:
Approximately 8 ha (in two patches)
13. Dry Creek Dams (unprotected, Rural Conservation Zone)
This site is described in Schulz et al (1991) and was recorded as ‘Plains Grassy Wetland’ under Time-stamping during a
very dry phase. It was also inspected in the field on 1 August 2012. The site consists of three distinct areas. The
largest zone is a deep, steep sided dam with no emergent vegetation, not referrable to SHW. Above this is a narrow,
rocky drainage line with quite steep sides. This area is in good condition with relatively few weeds and a high cover of
native species (including high cover of Themeda triandra, and several “sensitive” species such as Dianella sp. aff.
longifolia (Benambra) and Cullen parvum). However its character as a defined creek with an obvious slope excludes it
from being considered SHW, although some very small pools within it may be SHW, if not for their small size. Above
these zones is a small open boggy flat, dominated by Eleocharis acuta that drains into the creek. This area has the
character of SHW however it is smaller than the size threshold for the community.
EC type?
No
EC condition?
NA
Outcome
Delete from SHW dataset.
Area of SHW
none
14. Kororoit Creek Wetland No. 3 (North East Beattys Road / Mt Cottrell Road) (protected).
The aerial imagery suggests that the outer portion of this wetland supports woody species (Muehlenbeckia florulenta) at
a density too high to meet the criteria for SHW, while the inner portion of the wetland is likely SHW. Part of the wetland
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has been cropped in the past. It was not visited as part of this assessment, however Cook et al (2013) visited the site
and confirmed that it was SHW, possibly “high quality”.
EC type?
Yes excluding woody margins
EC condition?
Yes
Outcome
Retain in SHW dataset, removing dense Muehlenbeckia areas
Area of SHW
Approximately 7.5ha
15. Chartwell Wetland No.2 (Hopkins Road/Middle Road) (unprotected, Farming Zone)
This area was assessed under Time-stamping, and was assigned to ‘Plains Grassland’. It was not assessed by DEPI
Like the other wetland in Chartwell assigned to Plains Grassland (Chartwell No.1), the aerial photographs show patches
of very pale soil consistent with other known patches of SHW, and it is assumed that this wetland is similar.
EC type?
Yes, but probably on the drier margins of the SHW
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 4ha
16. Chartwell Wetland No. 3 (NW of Davis Road / Dohertys Road) (unprotected, Urban Growth Zone).
This wetland complex crosses several parcels, and contains four dams. Aerial images suggest it has never been
cropped and show that it is not woody. Two portions of it were assessed under Time-stamping, one as native vegetation
(Plains Grassy Wetland), the other as non-native vegetation (already removed from initial dataset). No data exist for the
remainder of the wetland.
EC type?
Yes
EC condition?
Probably
Outcome
Retain in SHW dataset
Area of SHW
Approximately 5ha in several patches
17. Tarneit Wetland (south east of Middle Road / Hopkins Road) (unprotected, Urban Growth Zone).
This wetland was mapped as ‘Plains Grassy Wetland’ under Time-stamping and assigned a lack of weeds score which
implied the weed cover was less than 50 per cent. The aerial photo suggests it has never been ploughed and is not
woody. Together these data strongly suggest the wetland is SHW.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately4ha
18. Plumpton Creek Wetland (north west of Tarleton Road / Plumpton Road) (unprotected, Urban Growth Zone
and Urban Flood Zone).
This wetland was not assessed as part of Time-stamping. It was not assessed by DEPI Aerial imagery shows it is not
woody and has probably never been cropped. It is associated with a drainage line unlike typical SHW however it
appears to be a large basin with the character of SHW.
EC type?
Yes
EC condition?
Unknown
Outcome
Retain in SHW dataset
Area of SHW
Approximately3.4ha
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19. Hopkins Road Wetland (near Boral Quarry, Rockbank) (unprotected, Special Use Zone 1).
This area was assessed under Time-stamping, and was assigned to ‘Plains Grassland’. It was not assessed by DEPI It
is assumed that this site is similar to the other wetlands in Chartwell assigned to Plains Grassland (Chartwell No.1)
EC type?
Yes, but probably on the drier margins of the SHW
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately3ha
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Northern Growth Corridor
20. Hearnes Swamp (unprotected, Rural Conservation Zone, Urban Growth Zone, Urban Flood Zone, Farming
Zone)
Hearnes Swamp was once a very large wetland (larger than 300 ha) out of which the Merri Creek emerged near Wallan.
It was likely once SHW in its entirety, judging by the species composition of the remnant vegetation on the railway verge
and early descriptions before it was modified (“…quite dry in summertime, is a sheet of shallow water in winter.” Anon
1871). Only 146 ha of this area is within the growth corridor. This area is divided by tenure into three distinct units,
including the railway line which runs across the middle of the swamp. Given the size and potential importance of this
swamp, Figure 3 shows the locations of the areas mentioned
The western section of the swamp (Figure 5 – Area A) appears to have been previously cropped however it is not under
a regular cropping regime currently. It was not assessed in Time-stamping and no published biological data are known.
Access was denied for field inspection. The area was viewed from the rail-side and the laneway that runs along the
northern boundary of the growth corridor on 13 August 2012. The area was largely dominated by introduced pasture
species (Phalaris aquatica, Lolium sp., Plantago lanceolata, see Figure 6). In some areas, a native Juncus species
formed patches with cover exceeding 50 per cent. These small patches represent degraded SHW but the bulk of the
area no longer meets the condition requirements.
The wide railway verge (Figure 5- Area B) supports extensive stands of native wetland vegetation, most of which is
referable to SHW (excluding dense beds of Phragmites australis in dams, channels and low-points and weed-invaded
areas). Most of this area is dominated by Poa labillardierei and Carex species. It is well known to support populations of
two EPBC listed species (Xerochrysum palustre and Senecio psilocarpus) and numerous state and regionally significant
species.
Access to the area east of the railway line was denied. The area was not assessed as part of Time-stamping. Aerial
imagery suggests that portions have been cropped. A consultant’s report (ERM 2007) shows broad areas of nativedominated and non-native vegetation, with some native areas including wetlands. Investigation from the railway verge
indicated that the northern portion of this property (Figure 5 –Area C) is dominated by pasture species, and is virtually
devoid of native vegetation. The southern section (Figure 5- Area D, Figure 7), however, contains a remarkably intact
stand of wetland vegetation clearly referrable to SHW. This area (approximately10 ha) is dominated by Poa labillardierei
(80 per cent cover) and a ‘fence-line’ assessment also indicated that a number of species indicative of the highest
quality SHW were present (including Asperula conferta, Craspedia pauldicola, Calocephalus lactues and a Ranunculus
species. Senecio psilocarpus has been recorded from this area in the past TSSC 2012). Weeds were currently at very
low levels in this area (less than 5 per cent). Another large portion of Hearnes Swamp (Figure 5 – Area E) could not be
viewed. This area appears to have never been cropped, and is shown as native vegetation by ERM (2007). This area is
assumed to be SHW.
EC type?
Yes
EC condition?
Mostly No. Small patches Yes
Outcome
Remove most of wetland from SHW dataset
Area of SHW
Aproximately 55 ha.
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Figure 5. Division of the extensive Hearnes Swamp area
Figure 6. The degraded western half of Hearnes Swamp (shown as Figure 5 Area A). The predominant species are pasture grasses. A few native
Poa labillardierei and Juncus species can also be seen.
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Figure 7. An excellent example of SHW in the eastern portion of Hearnes Swamp (shown as Figure 5d).
21. Inverlochy Swamp (unprotected, Urban Flood Zone, Urban Growth Zone)
Inverlochy Swamp is part of a large system of wetlands (100s of ha) that once flowed from the base of the scoria cone of
Mount Fraser through a series of basins and drainage lines into Kalkallo Creek. The upper part of this system is a woody
wetland dominated by Leptospermum lanigerum. Below this is a reedy swamp dominated by Phragmites australis,
neither of which are SHW. Below this, the original character of the system is poorly known, however judging by the
frequent occurrences of Poa labillardierei and Eleocharis acuta on roadsides, much of the area was likely SHW.
Inverlochy Swamp is the largest basin in this system. No existing information on this wetland is known and site access
was denied. However, a clear view of the wetland is available from the Hume Highway the entire area has been
ploughed recently, and no native vegetation could be discerned on site (Figure 8).
EC type?
Formerly yes
EC condition?
No
Outcome
Delete from the SHW dataset
Area of SHW
None
Figure 8. The former Inverlochy Swamp now devoid of native vegetation.
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22. Kalkallo Creek Wetland cluster (unprotected, Urban Growth Zone, Farming Zone)
These two indistinct wetland patches covering approximately 27 ha in total form the lower part of the Inverlochy Swamp
system. No existing data is available and these wetlands were not assessed as part of Time-stamping. Aerial imagery
shows that this area has been drained by numerous channels however the effect on the wetlands is not known. Most of
the wetland area can be viewed adequately from the roadside. A visit on 13 August 2012 confirmed that most of the
southern half of each wetland was non-native vegetation dominated by pasture weeds. A few patches of native Juncus
probably meet the SHW native cover thresholds. The northern section could not be adequately seen and is retained in
the dataset as a conservative estimate.
EC type?
Likely
EC condition?
Mostly not
Outcome
Delete areas of known non-native vegetation from the SHW dataset
Area of SHW
Approximately 11 ha
23. Curly Sedge Creek Wetland (protected)
This site of approximately 12ha lies within the Craigieburn Grasslands Flora and Fauna Reserve. It was visited on 15th
August 2012. Most of the wetland is dominated by introduced species (Plantago coronopus, Juncus acutus and others).
Only one distinct area was dominated by native species. This area had almost total cover of Carex tasmanica, an
extremely rare species that rarely dominates wetland vegetation. Several herb species (e.g. Pratia irrigua) were also
present. The SHW description does not make it clear how this unusual case should be treated. The landscape context
is consistent, being a seasonally inundated wet flat in a fertile landscape, however the overwhelming dominance by a
single sedge species and the probability that the site is sub-saline (given the species composition) suggests that it should
not be assigned to SHW.
EC type?
Yes, but marginal
EC condition?
Mostly No
Outcome
Delete wetland from SHW dataset
Area of SHW
None
24.Springs Hill Crater Wetland (unprotected, Rural Conservation Zone)
This unusual site occupies a gilgai plain within the broad crater of a volcano, between Beveridge and Wallan (Hanks
1955). The site was not assessed as part of Time-stamping, and no other information is available that describes the
vegetation. The aerial photographs show what appears to be a treeless gilgai plain that has been occasionally cropped
(2009 and 2012). This site was veiwed in late 2012 from the Old Hume Highway (where the road is elevated on the
slopes of Mt Fraser) and found to have been recently ploughed and sown to a grain crop. It was not SHW when
observed, although its long term prognosis and restoration potential are uncertain. Figure 9 shows an aerial image from
2013 that shows the extent of the ploughing.
EC type?
Probably
EC condition?
No
Outcome
Delete wetland from SHW dataset
Area of SHW
None
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Figure 9 Aerial image from 2013 that shows the cropping in Springs Hill Crater.
25. Donnybrook Road Wetland No. 1 (unprotected, Urban Growth Zone)
This site was assessed as Plains Grassy Wetland under Time-stamping during a wet phase and is likely to be SHW.
EC type?
Yes
EC condition?
Yes, but possibly marginal
Outcome
Retain in SHW dataset
Area of SHW
Approximately 4 ha
26. Donnybrook Road Wetland No. 2 (unprotected, Urban Growth Zone)
This site was assessed as Plains Grassy Wetland under Time-stamping and is likely to be SHW.
EC type?
Yes
EC condition?
Yes, but possibly marginal
Outcome
Retain in SHW dataset
Area of SHW
Approximately 3 ha
27. Donnybrook Road Wetland No. 3 (unprotected, Urban Growth Zone and Urban Flood Zone)
No data is available for this area, however the aerial imagery indicates there are no trees and it has never been cropped.
This site was edited to remove rocky rises initially included within the wetland.
EC type?
Probably
EC condition?
Probably
Outcome
Retain in SHW dataset
Area of SHW
Approximately 3 ha
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Western Grassland Reserve
28. Balls Wetland complex (protected)
This wetland was assessed by the Growth Areas Authority (GAA) surveys undertaken in 2008-09 (GAA 2010) and
Australian Ecosystems (2011) and was confirmed to be Plains Grassy Wetland with a composition consistent with SHW.
Although ploughed in the past, and of low species richness, it contains a number of species consistent with higher quality
SHW (Asperula conferta, Mentha satureoides, Teucrium racemosum).
EC type?
Yes
EC condition?
Yes, but possibly marginal
Outcome
Retain in SHW dataset
Area of SHW
Approximately 27 ha
29. Rabbiters Lake (protected)
Rabbiters Lake is described in detail in Schulz et al (1991). The swamp of approximately 22 ha is ringed by woody
vegetation and not SHW. The inner wetland contains a diverse array of grasses and herbs forming patches or zones of
local dominance. Some of these are consistent with SHW (Myriophyllum spp., Amphibromus nervosus, Marselia
drumondii, Rytidosperma duttonianum). Another broad zone, however, is dominated by Eragrostis infecunda, a species
inconsistent with SHW when dominant (TSSC 2012). Aerial imagery shows the area has not been cropped. Access to
this site was not granted. In order to retain areas of SHW but exclude Eragrostis-dominated areas the aerial photo was
examined closely and areas were excluded that displayed the distinctive uniform grey, clump-forming pattern typical of
Eragrostis. It should be noted that this method is imprecise.
EC type?
Partly
EC condition?
Yes
Outcome
Refine mapping to exclude probable non SHW
Area of SHW
Approximately 13.5 ha
30. Lollipop Creek Wetland (Lollipop Creek / Greens Road) (protected)
No data are available for this area however the aerial imagery confirms there are no trees and the site has not been
cropped.
EC type?
Probably
EC condition?
Probably
Outcome
Retain in SHW dataset
Area of SHW
Approximately 15 ha
31. Baths Swamp (protected)
This wetland of approximately 20 ha was described by Schulz et al (1991) suggesting that it contained patches referrable
to SHW as well as other patches dominated by species inconsistent with SHW. It was visited in 2011 (not for the
purposes of this assessment), and found to be dominated strongly in most by Eragrostis infecunda, a species
inconsistent with SHW (Figure 10). It is likely that only the centre of the wetland meets the criteria for SHW.
EC type?
Mostly not
EC condition?
Yes
Outcome
Delete most of wetland from SHW dataset
Area of SHW
Approximately 3.5 ha
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Figure 10. Baths Swamp showing the near complete dominance by Eragrostis infecunda over most of the wetland and Eucalyptus camaldulensis
around the edges.
32. Richmonds Grass Swamp (protected)
This site was described by Schulz et al (1991), in terms that suggest it was then a high quality example of SHW. It was
dominated by Rytidosperma duttonianum, Eleocharis acuta, and Lachnagrostis filiformis, and supported numerous herbs
including Asperula conferta, Calotis scapigera, Eryngium vesiculosum and Lobelia pratioides. This site was visited in
October 2012, after being dry for many years, and was found to retain many of its values. The grasses described by
Schulz et al (1991) were only present in low abundance, and the most abundant species is Eleocharis acuta. Although
sparsely distributed, several species indicative of high quality SHW remain (Amphibromus sp., Brachyscome basaltica,
Lobelia pratioides, Marselia drummondii). As shown in Figure 11, the cover of Eleocharis acuta approaches levels
inconsistent with SHW however the overall species composition and the history of the site suggest that categorisation of
SHW is appropriate.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Aprpoximately 14.5 ha
Figure 11. Richmonds Grass Swamp showing Eleocharis acuta, Amphibromus sp., Brachyscome basaltica and Marselia drummondii.
33. Balls Swamp (protected)
This wetland was described by Schulz et al (1991), by the GAA surveys in 2008-9 (GAA 2010) and by Australian
Ecosystems (2011). Although it is an intact wetland with many of the characteristics of SHW, both Schulz et al (1991)
and Australian Ecosystems (2011) described dominance by Eragrostis infecunda, which is a contra-indicative species for
SHW. The GAA surveys, in contrast, described it as Plains Grassy Wetland (consistent with SHW), however the swamp
was dry at the time.
EC type?
No
EC condition?
No
Outcome
Delete from SHW dataset
Area of SHW
None
34. Target Range Swamp (protected)
This swamp of approximately14ha was assessed by Schultz et al (1991) and described as a freshwater marsh
dominated by Rytidosperma duttonianum and Amphibromus nervosus with some Eragrostis infecunda. This composition
is consistent with SHW. Aerial imagery confirms the area has not been cropped. The swamp was again surveyed in
2008-9, and described as Cane-grass wetland (generally inconsistent with SHW) and the northern corner of the swamp
was mapped as non-native vegetation.
EC type?
Probably
EC condition?
Yes
Outcome
Retain most of wetland in SHW dataset, other than northern corner
Area of SHW
~12 ha
35. One Tree Hill Swamp (protected)
This swamp, associated with One Tree Hill near Eynesbury, was visited by DEPI and by Australian Ecosystems in 2011.
It is a large, intact example of SHW, dominated strongly by Marselia drumondii and including a range of other native
species (many rare species and/or species characteristic of high quality SHW) such as Damasonium minus, Gratiola
pumilo, Isoetes drumondii, Pilularia novae-zelandiae, Eleocharis macbaronnii, Elecocharis pallens) (Figure 12).
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EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately13 ha
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Figure 12 An example of SHW at One Tree Hill Swamp.
36. Greens Road Swamp East No. 1 (protected)
This wetland of 8 ha was described by Schulz et al (1991) in terms that suggest it may be SHW. The GAA surveys (GAA
2010) designated it non-native vegetation however it was dry at that time. It remains unploughed. When viewed from a
distance it appears to be strongly dominated by Eragrostis infecunda (inconsistent with SHW).
EC type?
Probably not
EC condition?
Probably
Outcome
Delete from SHW dataset
Area of SHW
None
37. West Quandong Swamp (protected)
This wetland was described by Schulz et al (1991) and assessed in the field in 2008-09 (GAA 2010). It is a good
example of SHW, being a freshwater meadow dominated by Rytidosperma duttonianum, Amphibromus nervosus,
Lachnagrostis filiformis with numerous herbs.
EC type?
Yes (but cover of Eragrostis unknown)
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 8 ha
38. Bulban Rd Wetland (south east of Bulban Road / Edgars Road) (protected)
This area was mapped as ‘Plains Grassland’ in 2008-09 (GAA 2010) confirming it retains some native vegetation but
providing no evidence of wetland vegetation. However, the aerial photographs show a distinct Gilgai plain with very pale
soil, characteristic of SHW. No other information is available for this area however the aerial imagery confirms there are
no trees and that the site has never been cropped.
EC type?
Probably
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 7 ha
39. Manor Lakes West Wetland (North Greens Road) (protected)
This area is visible from Greens Road, and appears to be SHW. It has been sprayed and the soil has been disturbed
and is therefore likely to be of relatively low quality.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 10 ha (in two patches)
40. Rabitters Swamp (protected)
Rabitters Swamp was described in detail in Schulz et al (1991) as an ephemeral freshwater meadow dominated by
species characteristic of SHW (Rytidosperma duttonianum, Poa labaillardierei, Lachnagrostis filiformis, and a range of
herbs). Other parts of the wetland are woody and not consistent with SHW (Eucalyptus camaldulensis, Muehlenbeckia
florulenta). Aerial photos indicate that the wetland has never been cropped or drained and is likely intact.
EC type?
Yes, excluding treed areas.
EC condition?
Yes
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Outcome
Retain in SHW dataset
Area of SHW
Approximately 17 ha
41. Live Bomb Wetland (North East Live Bomb / Bulban Road) (protected)
No data is available for this area however the aerial imagery confirms there are no trees and the site has never been
cropped.
EC type?
Probably
EC condition?
Probably
Outcome
Retain in SHW dataset
Area of SHW
Approximately 6 ha
42. Mambourin Wetland (South of Kirksbridge Road) (protected)
This wetland was assessed as Plains Grassy Wetland (generally consistent with SHW) by the GAA surveys in 2008-09
(GAA 2010). No other data is available for this area however the aerial imagery confirms there are no trees and the site
has never been cropped.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 6 ha
43. Greens Road Swamp East No. 2 (protected)
This wetland was described briefly by Schulz et al (1991) as being dominated by Amphibromus nervosus and was
assessed as ‘Plains Grassy Wetland’ in the GAA surveys of 2008-09 (GAA 2010). No other data are available.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 5 ha
44. Black Forest Road Wetland (protected)
This wetland is visible from the roadside and was assessed in October 2012. It is strongly dominated by Rytidosperma
duttonianum and is referrable to SHW.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 5 ha
45. Kirksbridge Road West Swamp (protected)
This swamp was described briefly by Schulz et al (1991) and was observed from the roadside in August 2012. It is
strongly dominated by Rytidosperma duttonianum and is referrable to SHW, however it does not appear to contain many
native species.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 4 ha
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46. Cobbledicks Ford Wetland cluster (protected)
This cluster of three wetlands was surveyed by Australian Ecosystems (2011) and was also visited during August and
October 2012. All three wetlands are referable to SHW, although they are weedy on their margins and have patches
where Eleocharis acuta is excessively abundant for SHW (TSSC 2012). The western-most wetland is the most diverse
and contains a range of species indicative of high quality SHW as well as some rare species (Eleocharis macbarronii,
Eleocharis pallens, Gratiola pumilo, Isoetes drummondii, Lobelia pratioides, Marselia costulifera, Pilularia novaezelandiae). An example of SHW in this wetland cluster is shown in Figure 13.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 10 ha (in 3 patches)
Figure 13. An example of SHW at Cobbledicks Ford showing high abundance of Eleocharis acuta.
47. Little River Wetland (south of Kirksbridge Road, west of Little River) (protected)
No data are available for this area however the aerial imagery confirms there are no trees and the site has never been
cropped.
EC type?
Yes
EC condition?
Yes
Outcome
Retain in SHW dataset
Area of SHW
Approximately 4 ha
48. Little River South Wetland (south east of Kirksbridge Road / Little River Ripley Road) (protected)
This low lying, grey soil plain was inspected on 25 February 2012 and was found to be dominated mostly by dryland
grassland species and is therefore considered slightly too dry to be SHW.
EC type?
No
EC condition?
Yes
Outcome
Delete from SHW dataset
Area of SHW
none
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South East Growth Corridor
49. Muddy Gates Lane Swamp complex (south west of Pattersons Road / Muddy Gates Lane) (unprotected,
Urban Growth Zone)
This site was not detected by Time-stamping and is not included in the Wetlands 94 or EVC 2005 datasets. Therefore, it
did not feature in the preliminary SHW dataset being assessed here. However, unpublished data was provided to DEPI
by ecological consultants who have assessed the site in the past. A large wetland occupies the broad flat on a drainage
line which flows into the heavy soil plain once occupied by the Clyde-Tooradin grassland (Cook and Yugovic 2003). The
creek is now drained and flows into Evans Inlet at Tooradin. Several smaller wetlands occupy isolated depressions in
the nearby paddock. The species composition of these areas is consistent with high quality SHW. The dominant
species include Amphibromus nervosus, Deyeuxia quadriseta, Poa labillardierei and Rytidosperma duttonianum. Many
other species occur that are typical of high quality sites (TSSC 2012) including Asperula conferta, Eryngium vesiculosum,
Isoetes drummondii, Microtis parvifolia, Montia australasica. The site also supports a population of a Prasophyllum
which is likely to be P. frenchii, listed as endangered under the EPBC Act. The species is otherwise an undescribed and
very rare taxon allied to P. diversifolium. Weed cover at the site has not been assessed since 2006, however, some
weed species were observed to be significantly impacting the native vegetation at that time, notably Alopecurus
geniculatus. This site was initially excluded from the SHW dataset on the basis of aerial photograph interpretation, as
the main wetland area is associated with a defined creek line. However, advice based on a site inspection suggests that
the characteristics of the site are consistent with SHW.
EC type?
Yes, but associated with a creek-line
EC condition?
Probably, but may be patchy
Outcome
Add to SHW dataset
Area of SHW
Approximately 10 ha (several patches)
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Results: spatial assessment of impact
Maps
The datasets described above were used to derive a spatial assessment of the distribution of SHW across the Melbourne
SIA area. This spatial data is shown in Figures 14, 15 and 16.
Figure 14. The distribution of SHW in the Western Growth Corridor and the Western Grassland Reserves.
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Figure 15. The distribution of SHW in the Northern Growth Corridor.
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Figure 16. The distribution of SHW in the Southern Growth Corridor.
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SHW impacts across the Melbourne SIA region
The data described above have been used to assess the spatial impact of Melbourne’s growth program on SHW. The
data suggest that the areas affected are:
Protected in Conservation Areas:
66 ha (11 per cent)
Protected in the Western Grasslands Reserve
280 ha (50 per cent)
(Total protected
346 ha (61 per cent))
Removed and offset
103 ha (18 per cent)
Removed and not currently offset
117 ha (21 per cent)
(Total removed
220 ha (41 per cent))
SHW impacts across Victoria
When the EVC 2005 datset is used to define SHW, the SIA has the following impact on the community state wide:

Removed:
125 ha (1.0 per cent)

Protected:
140 ha (1.1 per cent)

Unaffected (outside SIA influence):
12,623 ha (97.9 per cent)
When the Wetlands 1994 datset is used to define SHW, the SIA has the following impact on the community state-wide:

Removed:
34 ha (0.3 per cent)

Protected:
35 ha (0.3 per cent)

Unaffected (outside SIA influence):
10,875 ha (99.4 per cent)
These figures suggest that the impact of the SIA is relatively small across Victoria. They also confirm that the degree of
protection is roughly equal to the degree of loss (compare with above, which suggests 66% protected).
The discrepancy between the two datasets used to assess the area of SHW reflects the limitations of the datasets.
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Prospects for protection and management
Wetlands: dynamic ecological character
Ephemeral wetlands are inherently dynamic. Most SHWs in the Melbourne region have relatively small catchments and
fill in response to local rainfall which varies in quantity and timing from year to year. SHW may recover after being dry
for many years, and may tolerate several years of inundation (TSSC, 2012). These conditions favour a suite of species
(plants and animals) that tolerate frequent changes in conditions. Such plants include those with resilient organs that
persist underground during dry phases (rhizomes, corms, etc) and grow rapidly when wet, as well as annual species that
colonise mud or water. Such strategies are common in seasonal wetlands worldwide (Deil 2005). Relevant animal
species include those that tolerate dry periods as eggs (e.g. shield shrimps) or those that are able to disperse between
wetlands to exploit them in wet phases (e.g. many birds). Different plants and animals may flourish under certain
conditions, then emigrate or retreat under others, so that the same wetland may be dominated by different species at
different times, often following rapid growth of one species which temporarily ‘out-competes’ others (e.g. Marselia vs.
grasses vs. Eleocharis).
Despite this natural dynamism, different wetlands do maintain distinctive characteristics driven by long-term climatic or
hydrological trends. For example, in the Melbourne region, marginal differences in long term ‘wet-dry’ cycles can
produce a range of vegetation types, from Eragrostis infecunda and/or Muehlenbeckia florulenta at sites such as the
Werribee Plains that experience prolonged drought and prolonged inundation (Schultz et al 1991, Roberts and Marston
2000), to SHW dominated by Poa labillardierei or Glyceria in places that are often wet and rarely totally dry such as the
north and east of Melbourne).
Wetlands: Impacts
The historic legacy
The general processes and impacts of degradation described in TSSC (2012) are common to lowland ephemeral
wetlands in many places (Davis and Froend, 1999), however the degree and scope of some specific impacts in the
Melbourne area are worth noting. It is important to note that the following summary is based on anecdotal observation,
and is not supported by published data specific to SHW:

Virtually all SHWs have been grazed over long periods. Grazing causes physical damage to wetland soils
(pugging), selectively removes palatable species, and may increases nutrients in some circumstances. Species
that are very sensitive to grazing have mostly been removed, and only exist in small numbers in a few sites (e.g.
Hearnes Swamp).

Approximately half of all SHWs have been ploughed in the recent past (visible on aerial images). As noted
above, repeated ploughing combined with cropping may completely degrade or remove SHW, however SHW
may survive single or infrequent ploughing remarkably well particularly in the absence of weeds and in
favourable climatic conditions. Recovery after ploughing is facilitated by the survival of tough, perennial
underground structures such as rhizomes, that allow rapid regrowth under favourable conditions. Some
examples of SHW have probably been shifted from dominance by sensitive species to less sensitive species
due to past ploughing, and thus some native species may indicate a more degraded system. There is not
enough research to determine whether this has occurred in any particular case, or whether the patterns are
natural.

All SHWs have some degree of weed invasion. SHW may, however, be relatively resilient to weeds because
the dynamics of wetland filling and drying means that many weeds do not get an opportunity to drive native
species out of the site. Indeed, many weeds that are abundant during dry phases are effectively ‘drowned’ when
the wetlands fill, and have virtually no impact on native wetland species. A few species of wetland weed,
however, can compete directly with native species in wet phases (e.g. Paspalum distichum).

Most SHWs have experienced hydrological modification, however the type and degree of impact vary greatly.
Modifications include the following:
– Dams within patches of SHW may deprive the remainder of the wetland of some water causing subtle
changes in wet-dry cycles. The earth removed to make the dam is often left on site and can develop
permanent weed cover.
– Dams which hold water in former SHW may fill more often than they once did leading to vegetation changes
that reflect the new hydrological regime (which may no longer be SHW).
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– Many larger swamps have been drained so they can be cropped or grazed using channels that divert water
away from the wetland.
– Groundwater harvesting may deprive SHW of water however the magnitude of this problem is likely small in
the Melbourne area.

Most SHWs have received nutrient inputs from fertiliser application on surrounding land (or to the wetland itself
where cropped). This may cause shifts in vegetation composition and the dynamics of nutrient cycling in the
wetland. Most studies of eutrophication are in permanent lakes, estuaries and wetlands, and so the effects of
eutrophication in SHW are unknown.

Most SHWs have had the surrounding native vegetation removed or degraded. The impacts of this are subtle,
but are likely to include elevated levels of weed invasion, altered animal communities, and altered nutrient
inputs.
Urban and industrial development
Urban and industrial development provides potential new impacts including the following:

Clearing of SHW for development.

The conversion of surrounding land from farmland to urban land inevitably changes the degree to which water
runs off or penetrates the soil. Land use changes in a catchment will almost always change wetland hydrology
unless managed with great care. These changes may be large enough that SHW is removed, and different
vegetation covers the site (permanent aquatic vegetation, dryland vegetation, etc). In some cases, the changes
may be very subtle, so that SHW may remain for a long time.

Past developments have converted SHW into permanent lakes, which may function as wetland habitat, but not
as SHWs.

Once surrounded by development works, SHW may be vulnerable to damage by bikes, cars, trail bikes, etc.

Urban development brings with it a suite of cultivated plants, increasing the risk of weed invasion.

Domestic cats and dogs may disturb native animals within SHW.

SHW are vulnerable to being shaped by earth moving machinery to control water flows (retarding basins, etc).

Stormwater input may increase the length and depth of inundation and may bring excess nutrients into SHWs.

In addition to catchment hydrology, development brings structural changes that may alter the suite of fauna
which visit the sites.
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Wetlands: condition of sites
Table 1 summarises the likely condition of the SHW sites identified above. This information may assist with the
prioritisation of sites for protection and may clarify their prognosis for management.
Only those factors which can be adequately assessed using remote means are included here. Sites were assessed as
follows:

‘Crop’: Plough lines are clearly visible on at least one air photo between 2006 and 2010.

‘Dam’: A dam is present within a SHW, that alters its hydrological regime.

‘Flow’: The hydrology of the wetland has been altered by works up- or down-stream.

‘Drain’: The wetland has been drained by channels which divert water away from it.

‘Spray’ : There are obvious ‘lines’ visible on air photographs which indicate boom or aerial spraying of
herbicide (mostly for past control of Nassella trichotoma).

‘~100m buffer’: Native vegetation immediately bordering the SHW has largely been removed.

‘~500m buffer’: Native vegetation within approximately 500 m of the SHW has largely been removed.

‘Obs. Veg.’: Direct observations have confirmed the vegetation quality recently (since 2011).
Table 1. SHW site condition
Wetland
Area
(ha)
crop
dam
flow
drain
spray
~100m
buffer
~500m
buffer
Obs.
Veg.
WESTERN GROWTH CORRIDOR
Unprotected
3. Troups Rd Swamp
1.5
Good
4. Rockbank Railway Swamp
8.8
?
5. Paynes Rd Swamp
4.7
Good
6. Wyndham Vale Swamp
6.2
?
8. Deanside East Wetland
4
part
Mod.
10. Kororoit Creek No. 1
7.2
part
?
11. Rockbank No. 1
4.4
?
15. Chartwell No. 2
4
?
16. Chartwell No. 3
5
18. Plumpton Creek Wetland
3.4
?
19. Hopkins Rd Wetland
3
?
part
?
Conservation Areas
part
?
2. Deanside West Wetland
13.5
7. Chartwell Wetland No. 1
9.9
?
12. Kororoit Creek No. 2
5.7
Good
14. Kororoit Creek No. 3
3
part
?
Note: Green cells indicate that the impact is present
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Wetland
Area
(ha)
crop
dam
flow
drain
spray
~100m
buffer
~500m
buffer
Obs.
Veg.
NORTHERN GROWTH CORRIDOR
Unprotected
20. Hearnes Swamp
55
Exc.
22. Kalkallo Creek Wetland
10.5
?
24. Springs Hill Crater Wetld.
4.8
?
25. Donnybrook Rd No. 1
4
?
26. Donnybrook Rd No. 2
3
part
?
27. Donnybrook Rd No. 3
3
part
?
Conservation areas
23. Curly Sedge Creek
2.6
Mod.
WESTERN GRASSLAND RESERVE
28. Balls Wetland Complex
27
Mod.
29. Rabbitters Lake
13.5
Good
30. Lollipop Creek Wetland
15
?
31. Baths Swamp
3.5
Good
32. Richmonds Grass Swamp
14.5
34. Target Range Swamp
11.9
?
35. One Tree Hill Swamp
13
Good
37. West Quandong Swamp
7.6
38. Bulban Rd Wetland
6.5
39. Manor Lakes West
10.2
40. Rabitters Swamp
16.7
?
41. Live Bomb Wetland
6.2
?
42. Mambourin Wetland
6.4
?
43. Greens Rd E Wetld.No. 2
5.3
?
44. Black Forest Rd Wetland
4.6
45. Kirksbridge Rd W Wetlnd.
4.2
Mod.
46. Cobbledicks Ford cluster
4.3
Good.
47. Little River Wetland
3.7
?
part
part
Good
?
?
part
part
?
part
Mod.
SOUTH EAST GROWTH CORRIDOR
Unprotected
49. Muddy Gates Lane
Good
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Prospects for management and restoration
This section provides a general discussion of the prospects for managing SHW in the context of development. It does
not provide advice regarding the management of any specific wetland. As in the section above, it is based on local
observation and studies from other areas.
Management
As a general principle it is preferable to conserve and manage larger sites and those sites that are surrounded by a
buffer that retains native habitat. Smaller wetlands within urban systems are less likely to be manageable in the longer
term. This principle reflects basic biogeogrpahic patterns related to extinction probabilities in areas of different sizes.
Many of the threats listed above can be controlled. For example, access can be restricted and weeds can be treated and
removed. Flooding, stormwater input and nutrient input can also be avoided by design. Other threats such as increased
weed invasion, increased domestic animal activity can be mitiagated or tolerated. Perhaps the most difficult threats to
manage are those that have widespread, diffuse origins, most notably altered catchment hydrology.
An important mechanism to minimise impacts on catchment hydrology is to impose a buffer zone around SHW. This
approach is advocated by the TSSC (2012), and has many benefits as it assists in managingweeds, pests, water inputs,
etc. However, it must be recognised that a ‘one-size fits all’ approach is not appropriate. The catchments of SHW vary
greatly in size and shape. Some SHWs (notably those formed by lava barriers) have very small catchments in one
direction, and very large catchments in others; others have catchments which extend a long way in all directions. Some
are steep, some are flat. Some SHWs have single points of inflow, some have many. Due to the irregular and subtle
terrain of the basalt plains, the nature of the catchment may not be immediately obvious, and requires subtle hydrological
interpretation. Furthermore, some threatening processes are related to the wetland catchment (e.g. hydrological
influences) while others may not be (e.g. public access).
Restoration
In many cases shallow wetlands are relatively easy to restore. Native plant species are able to quickly colonise
restoration sites and most of the naturally abundant native species are easy to propagate and source. Weed invasion is
are generally low and can be controlled.
However, there are some problems with wetland restoration. A widely documented issue (Zedler 2000) is the tendency
to create attractive, ‘generic’ wetlands that fail to collectively provide the subtle range of niches to allow the full suite of
wetland species to survive. Most restored wetlands are permanent wetlands, not SHW.
There is still scientific uncertainty regarding the best process for wetland restoration. and is it is difficult to create the
exact regime that favours a predetermined suite of species. For example, although there may be a desire to create a
wetland dominated by Glyceria or Amphibromus, environmental factors may result in a wetland where some other
species has come to dominate.
For these reasons the protection of existing sites is a higher priority than the creation of new sites.
Measures
The following principles have been developed for the protection of SHW in an urbanised landscape:

Prioritise the protection of existing sites .

Priroitise large sites.

Prioritise large buffers and preserve existing native vegetation around the wetlands where possible.

Control weeds using a targeted approach.

Prevent or minimise soil disturbance (particularly during development).

Prevent or minimise vehicle and foot access to the wetland.

Prevent or minimise stormwater inputs.

Retain seasonal wetlands (do not convert into permanent wetlands).

Communicate to the public that drying is a natural part of the SHW cycle, and that dry wetlands are neither
‘failed’, nor ‘degraded’.

Minimise hydrological change. This will require a detailed hydrological assessment. .

Consider enrichment planting with site-appropriate species, but only after the natural former species
composition of the individual wetland had been investigated in detail.
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Candidate sites outside Melbourne for future protection
The IWC dataset was filtered to identify high quality sites that are likely to be SHW and may be appropriate for future
protection. The results of this analysis are listed in Table 2. While these wetlands are likely to be good candidates for
protection, it must be emphasised that the IWC dataset only represents a pre-selected subset of Victorian wetlands, and
many other important sites may not be captured here.
Table 2. Potential wetlands derived from the IWC dataset
IWC ID
Location (Bioregion)
Predominant relevant
EVC
Area (ha)
Overall Score
(max 10)
Biota Score
(max 20)
7123188004
Edenhope (Wim)
Plains Sedgy Wetland
>140
8
17.3
7122106434
Heathfield (GleP)
Plains Sedgy Wetland
63.1
8
17
7224812109
Julumba (Wim)
Plains Grassy Wetland
49.6
9
18
7224484109
Charam (Wim)
Plains Sedgy Wetland
46.61
8
17.5
7522783933
Darlington (VVP)
Plains Grassy Wetland
37.18
8
17.7
7522880349
Streatham (VVP)
Sweet Grass Wetland
42.78
8
18.4
7122079329
Heathfield (GleP)
Aquatic Grassy Wetland
34.22
9
17.9
7422721450
Tatyoon (VVP)
Plains Grassy Wetland
32.83
8
18.95
7321012595
Yambuk (VVP)
Aquatic Grassy Wetland
32.16
8
16.6
7522869299
Streatham (VVP)
Plains Grassy Wetland
30.63
7
16.23
7825075656
Carag Carag (VRiv)
Plains Grassy Wetland
21.06
8
18.9
7322116168
Croxton (VVP)
Plains Grassy Wetland
20.47
7
17.79
Staff experience and knowledge of local areas in the Glenelg Hopkins and Corangamite CMAs also assisted in
identifying potential SHW sites on private property. Table 3 lists the general locationof these wetlands.
Table 3. Potential wetlands derived from CMA information
Location (Bioregion)
Predominant relevant EVC
Area (ha)
CMA
Birregurra (VVP)
Plains Grassy Wetland
81.08
C
Caramut (VVP)
Plains Grassy Wetland
61.55
GH
Darlington (VVP)
Plains Grassy Wetland
26.08
GH
Skipton (VVP)
Plains Grassy Wetland
2.23
GH
Darlington (VVP)
Plains Grassy Wetland
40.83
GH
Derrinallum (VVP)
Plains Grassy Wetland
~240
GH
Stockyard Hill (?)
Plains Grassy Wetland
4.04
GH
Derrinallum (VVP)
Plains Grassy Wetland
74
C
Mt Wallace (VVP)
Plains Grassy Wetland
~50
C
Mortlake (VVP)
Plains Grassy Wetland
15.05
GH
Streatham (VVP)
Plains Grassy Wetland
34.79
GH
Streatham (VVP)
Plains Grassy Wetland
15.27
GH
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Limitations
It is important to note that the data presented in this report are subject to limitations. Some of these limitations were
discussed above when describing each dataset. The following points, however, are are worth noting:

The report is based on a desktop analysis, with some field verification.

The definition of SHW used in assessments is open to interpretation in marginal sites.

The impact of cropping is difficult to assess, and difficult to apply as a definitive filter when detrmining wetland
condition.

This report is a ‘snap shot’ and not based on long-term understanding of the dynamics of the sites.

Aerial photograph interpretation is subject to user error.

The assessment is based on a mixed dataset, and many sites have not been assessed in the field.

The differing degrees of evidence for the occurrence and quality of SHW sites may falsely convey that some
sites are relatively more significant than others: Some unsurveyed sites are shown to have a large extent, while
their identity as SHW is unknown; while some smaller sites stand out as high quality sites largely because there
is more information that shows their values. The degree of assessment must be carefully considered when
using this information to make decisions about relative importance.

No systematic method other than field work can detect all patches of SHW, and it is possible that some sites
have not been detected.
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References
Anon (1871) The works on the north east railway. The Argus, 31st January 1871.
Australian Ecosystems (2011). Extent and species composition of selected wetlands within the proposed Western
Grassland Reserve. Unpublished data, commissioned by DSE.
Callanan M (1859) Country lots, Parish of Sherwood, County of Mornington. State Library of Victoria.
Cook D, Yugovic (2003) Clyde-Tooradin Grassland rediscovered. The Victorian Naturalist 120, 140-146.
Cook D, Just K and Jolly K (2013) Rockbank Area Wetland Survey. Unpublished report, Rakali Consulting, Chewton.
Corrick, A.H. and Norman, F.I. 1980 Wetlands of Victoria 1. Wetlands and waterbirds of the Snowy River and Gippsland
Lakes Catchment. Proceedings of the Royal Society of Victoria 91, 1-15
Davis, J.A. and Froend, R. (1999) Loss and degradation of wetlands in southwestern Australia: underlying causes,
consequences and solutions. Wetlands Ecology and Management 7, 13-23.
Deil U (2005) A review on habitats, plant traits and vegetation of ephemeral wetlands – a global perspective.
Phytocoenologia 35, 533-706
DEPI (2013) Biodiversity Conservation Strategy for Melbourne’s Growth Corridors. Department of Environment and
Primary Industries, East Melbourne.
DPCD (2009) Delivering Melbourne’s newest sustainable communities: Program Report. Department of Planning and
Community Development, East Melbourne.
DSE (2012a) Biodiversity Conservation Strategy for Melbourne’s growth corridors. Department of Sustainability and
Environment, East Melbourne.
DSE (2012b) Sub-regional species strategy for the Growling Grass Frog. Department of Sustainability and Environment,
East Melbourne.
Environment Australia (2001). A Directory of Important Wetlands in Australia, Third Edition. Environment Australia,
Canberra.
ERM (2008) An ecological assessment of Beveridge Rd, Beveridge, Victoria. Final Report to Beveridge Pastoral
Company. Environmental Resources Management (ERM) Australia, Docklands.
Foot HB (1857) Country allotments in the parish of Yallock, County of Mornington. State Library of Victoria.
Gilmore D (2011) Important sites for biodiversity conservation: Melbourne’s urban growth zones. Report to DSE. Biosis
Research, Port Melbourne.
GAA (2010) Biodiversity Assessment Report (Native Vegetation): Melton-Wyndham Investigation Area – Sections A-E.
Growth Areas Authority, Melbourne.
Hanks W (1955). Newer Volcanic vents and lava fields between Wallan and Yuroke, Victoria. Proceedings of the Royal
Society of Victoria 67, 1-16.
Roberts J, Marsten F (2000) Water regime of wetland and floodplain plants in the Murray-Darling basin: a sourcebook of
ecological knowledge. CSIRO Land and Water, Technical Report 30/00.
TSSC (Threatened Species Scientific Committee) (2012) Advice to the Minister for Sustainability, Environment, Water,
Population and Communities from the Threatened Species Scientific Committee (the Committee) on an Amendment to
the List of Threatened Ecological Communities under the Environment Protection and Biodiversity Conservation Act
1999 (EPBC Act): Seasonal Herbaceaous Wetlands (Freshwater) of the Temperate Lowland Plains.
Yugovic J, Mitchell S (2006) Ecological review of the Koo-Wee-Rup Swamp and associated grasslands. The Victorian
Naturalist 123, 323-334.
Zedler JB (2000) Progress in wetland restoration ecology. Trends in Ecology and Evolution 15, 402-407.
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Appendix 1: Locations of assessed sites.
The following maps show all sites that were assessed in section 5 (‘Targeted Assessments of larger potential SHW
Sites’), regardless of outcome. Many of these wetlands have been removed from the final dataset, as described in the
body of the report.
Figure 17. The distribution of all SHW sites assessed in the Western Growth Corridor and the Western Grassland Reserves.
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Figure 18. The distribution of all SHW sites assessed in the Northern Growth Corridor.
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Figure 19. The distribution of all SHW sites assessed in the Southern Growth Corridor.
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Appendix 2: Wetland Names
No formal or previously-used name could be found for the following sites. These names have been created for the
convenience of this report only:

Ballan Road Wetland

Chartwell Wetlands (Nos.1-3)

Paynes Road North Wetland

Kororoit Creek Wetlands (Nos.1-3)

Rockbank Wetland

Tarneit Wetland

Plumpton Creek Wetland

Hopkins Road Wetland

Kalkallo Creek Wetland

Curly Sedge Creek Wetland

Springs Hill Crater Wetland

Donnybrook Road Wetlands (Nos.1-3)

Balls Wetland Complex

Lollipop Creek Wetland

One Tree Hill Wetland

Bulban Road Wetland

Manor Lakes West Wetland

Live Bomb Wetland

Mambourin Wetland

Black Forest Road Wetland

Cobbledicks Ford Wetland

Little River Wetland

Little River South Wetland

Muddy Gates Lane Swamp Complex
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