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Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 1 of 11
Re: Ropes Creek Riparian Corridor Assessment
Introduction
SESL Australia has been engaged by Aecom (the Client) to undertake a soil resource assessment and survey
along Ropes Creek and the realigned tributary at Horsley Park (the Site).
The objective of this assessment is to characterise the physical and chemical properties of the surrounding soil
profiles and of the alluvial deposits associated with the creek line for the purpose of restoration of existing remnant
riparian vegetation and realignment of a tributary.
The natural soil landscape is a combination of “South Creek” and “Luddenham” (Hazelton and Bannerman, 1990).
This Luddenham soil landscape comprises of dark brown silty loam podsolics soils formed on Wianamatta Shales
often associated with Minchinbury Sandstone. South Creek soils are a sandy loam and derive from a floodplain of
drainage networks of the Cumberland Plain. Typically they have a deep profile that overlay bedrock or relic soils.
Both soil types are prone to waterlogging, flood hazards, permanently high water tables, erosion from water and
surface movement. Luddenham soils are highly erodible and have hardsetting surfaces
A full investigation was carried out to investigate the two drainage lines (Drainage Line 1 and Drainage Line 2) of
Ropes Creek. Drainage Line 1 is a 2nd order watercourse that requires restoration of existing
riparian vegetation. This report provides advice on the restoration of the 20m vegetated riparian zones along both
sides of the watercourse. Drainage Line 2 is not defined as a watercourse therefore can be realigned or relocated.
This report covers how to achieve this including stripping plans, reconstruction of soil profiles and compatible
Cumberland Plain vegetation types will be approved from a client species list.
Our Ref: B35587 C5852 Q4632.docx
31st July, 2015
Aecom
420 George Street
Sydney, NSW 2000
Attention: Mark Blanche
Dear Mark,
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 2 of 11
Methodology
The field assessment was carried out by Chantal Milner and Andrew Lynam of SESL on Friday 12th June 2015.
Based on a desktop review and in-situ surveying, SESL Australia designated nine (9) borehole locations for
sampling. Exact locations were defined after a site walkover and establishing the variations in the soil and
vegetative growth. Samples were collected by hand auger using the Free Survey technique, focusing on identifying
the main soil catenas and variability across the site – particularly with regard to slope position vs. topsoil depth and
vegetation diversity. Profile descriptions were made of the entire profile at each sampling location (Appendix B). A
map of the sampling locations is attached as Appendix A. A soil survey at this scale cannot provide detailed soil
mapping but only identify the main occurrences and variability. Three profiles were placed in the location of the
tributary creek realignment to investigate conditions at depth once the realignment is made.
The collected samples were analysed for a range of soil chemistry properties. Topsoils were tested for pH, EC,
exchangeable cations and plant available nutrients. Subsoils were tested for pH, EC and exchangeable cations. As
the site is to be revegetated with CPW, available phosphorus levels were also determined. This allows us to
determine whether phosphorus will be limiting to the success of the planting, as many CPW species are highly
phosphorus sensitive. As plants generally take their nutrients from the top 200 mm of soil, it is not necessary to test
for plant available nutrients in subsoils.
The pH, EC, exchangeable cations and plant available nutrients were all analysed utilising the Mehlich 3 extract.
Mehlich 3 (M3) estimates plant availability of most macro- and micronutrients on soils acid to neutral pH using a
dilute acid-fluoride-EDTA solution of pH 2.5. The method has shown to be well correlated to crop response to
fertilizer phosphorus and applicable for the determination of extractable potassium, calcium, magnesium, sodium
and micronutrients, such as manganese, iron, copper and zinc (Mehlich, 1984).
This report presents the findings from the field assessment, laboratory analysis, and provides recommendations to
ameliorate the soil for re-use.
Field & Laboratory Results
Topsoil Physical and Chemical Properties
The chemical test results are presented in Appendix C. Table 1 summarises the topsoil chemical test results for
Ropes Creek Drainage Line 1 (restoration of existing riparian vegetation), Table 2 summarises the topsoil
chemistry for Drainage Line 2 (creek realignment), Table 3 looks at the subsoil (Horizon A and B) for both Drainage
Lines 1 and 2.
The soils in each horizon remain generally consistent with only some variation. The overall trend seen in each
horizon is summarised as follows however a more in-depth interpretation is discussed after each table:
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 3 of 11
• Topsoil in Drainage Line 1: Dark brown silty loam to silty clay loam. Slight to strong acidity with desirably
low salinity. Highly magnesic and acidic aside from BH6, which is highly magnesic and sodic.
• Topsoil in Drainage Line 2: Dark brown silty loam to silty clay loam. Moderate acidity with desirably low
salinity. Highly acidic and sodic.
• Subsoil (B Horizon) for both drainage lines – Orange brown to dark yellow with some red and black
mottling silty clay. BH5 sandy clay. BH1 and BH3 are moderately to highly acidic and moderately to highly
saline. BH4, 6, 7, 8, 9 are slightly acidic with low salinity and BH5 is slightly alkaline and highly saline. All
subsoils are magnesic and sodic and BH1, 3, 6, 7, 8 and 9 are also acidic.
• Subgrade (C Horizon) for Drainage Line 2: The C horizon becomes more crumbly and less clayey. The soil
type is a light clay and a paler orange colour. Highly magnesic and highly sodic.
Table 1. Chemical analysis results of Ropes Creek Drainage Line 1 topsoil.
Sample Number
1 3 12 13 14 16
Sample Name BH1 0-340mm
BH2 0-300mm
BH6 0-250mm
BH7 0-200mm
BH8 0-300mm
BH9 0-270mm
pH in H2O 5.8 5.3 7.1 6.4 6.2 6
pH in CaCl2 5.04 4.76 6.24 5.69 5.47 5.2
EC dSm 0.04 0.04 0.12 0.15 0.04 0.04
Na mg/kg 20.4 64.2 330 275 123 85.9
Cl mg/kg 18.14 21.45 78.4 101.76 31.68 21.03
Na % CEC 0.9 3.6 10.9 6.6 2.3 2.2
K % CEC 2.9 0.6 1.8 2.9 0.9 1.4
Ca % CEC 30 16.6 35.6 35.7 41.7 32.3
Mg % CEC 22.8 26.8 52 54.7 27.3 28.7
H % CEC 43.1 51.7 0 0 27.8 35.2
Al % CEC 0 0.1 0 0 0 0
eCEC meq/100g
9.7 7.7 13.1 18.2 22.9 16.5
NO3 mg/kg 3.8 1.6 3.9 2.7 2.2 1.6
PO4 mg/kg 3.4 1.3 4.8 7.5 4.2 6.3
K mg/kg 108 21.2 91.4 205 80.8 89.6
SO4 mg/kg 14 11 11 14 6.5 10
Ca mg/kg 584 257 933 1301 1911 1069
Mg mg/kg 268 251 827 1211 759 574
Fe mg/kg 121.7 90.5 133.8 169.1 130.1 148.1
Mn mg/kg 71 205 93 148 161 130
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 4 of 11
Cu mg/kg 1.3 0.64 2.6 2.4 1.8 1.9
B mg/kg 0.1 0.1 0.4 0.1 0.1 0.1
Zn mg/kg 1.3 0.65 3.1 4.7 1.7 1.2
Drainage Line 1 Topsoil (Restoration of existing vegetation)
Samples were taken at varying distances from the creek line ranging from 10-100mm to determine how much the
chemistry altered with the presence of water. Samples taken less than 50m from the creek line are acidic and
magnesic however the same result was seen in samples taken at a much further distance of 100m from the creek
line. In conclusion closeness to the water makes little difference to the chemistry. The difference in chemistry
occurs with depth and the soil becomes more hostile with increasing depth.
The laboratory analysis indicates that the chemistry of the samples along Drainage Line 1 are fairly consistent.
They are all a dark brown silty loam to silty clay loam that are slightly to strongly acidic with desirably low salinity.
The majority of the samples are highly magnesic and acidic which have the potential for hardsettting soils. Overall
the nutrient levels are low aside from magnesium and manganese. Iron/Manganese concretions (“shotgun pellets”)
are common at the A/B boundary indicating intense wetting and drying cycles typical of the Eastern Australian
climate. This is a result not only of extreme variations in rainfall but poor internal drainage of the soils. The
exception to this chemistry is BH6 and BH7, which are highly magnesic and sodic. BH6 is also very slightly
alkaline.
Table 2. Drainage Line 2, topsoil chemistry.
Sample Number 4 7 10
Sample Name BH3 0-250mm BH4 0-330mm BH5 0-350mm
pH in H2O 5.7 5.8 6.7
pH in CaCl2 4.93 4.93 5.86
EC dSm 0.04 0.03 0.22
Na mg/kg 132 103 820
Cl mg/kg 27.05 18.96 218.54
Na % CEC 5 4.3 29
K % CEC 1.6 0.9 1.1
Ca % CEC 19 25.3 13.9
Mg % CEC 32.2 24.6 55.7
H % CEC 42.3 45 0
Al % CEC 0 0 0
eCEC meq/100g 11.5 10.4 12.3
NO3 mg/kg 2 1.6 6.7
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 5 of 11
PO4 mg/kg 0.9 2.1 1.5
K mg/kg 69.2 34.1 49
SO4 mg/kg 7.6 10 15
Ca mg/kg 439 527 343
Mg mg/kg 450 311 832
Fe mg/kg 142.9 118 167.5
Mn mg/kg 201 184 203
Cu mg/kg 0.8 0.6 1.8
B mg/kg 0.1 0.1 0.1
Zn mg/kg 0.65 0.65 0.8
Drainage Line 2 Topsoil (Proposed tributary)
Samples, BH3, BH4 and BH5 were taken at various locations along the proposed tributary (Drainage Line 2). BH3
and BH4 were taken towards the central side of the site whereas BH5 was taken at the eastern side. Chemically
BH3 and BH4 are similar as they both have moderate acidity and desirably low salinity. Their cation exchange is
highly acidic, highly magnesic and sodic which have dispersive and hardsetting characteristics. BH5 is located in
the lowest part of the creek profile and has very slight acidity and moderate salinity. The cation exchange is highly
magnesic and sodic. Nutrient levels overall are low for all bore holes aside from magnesium and manganese which
are high.
Magnesic and highly sodic soils are not ideal for creek lines as they are very dispersive and prone to erosion.
Applications of gypsum are required to help correct this chemistry.
Table 3. Subsoil (B Horizon and C Horizon) chemistry for Drainage Line 1 and Drainage Line 2.
Description Drainage Line 1 B Horizon
Drainage Line 2 B Horizon
Drainage Line 2 C Horizon
Sample Number
2 15 17 5 8 11 6 9
Sample Name
BH1 340-
700mm
BH6, 7, 8 Composite
BH9 270mm+
BH3 250-
930mm
BH4 330-
660mm
BH5 350-
600mm+
BH3 930-1100mm
BH4 660-
1120mm pH in H2O 4.8 6.2 6.2 5.7 6.3 8 5.6 6.3
pH in CaCl2 4.21 5.17 5.04 5.1 5.32 6.46 5.07 5.9
EC dSm 0.52 0.14 0.05 0.5 0.07 0.89 0.87 0.58
Na mg/kg 498 351 229 1306 343 2315 1440 1299
Na % CEC 10.2 6.5 4.5 26.3 8.2 54.1 34 38.4
K % CEC 0.6 0.7 0.8 0.7 0.8 0.5 0.7 0.7
Ca % CEC 2.7 27 18.6 1.8 15 8.7 1 3.1
Mg % CEC 28.2 35.8 44.7 50.4 48.5 36.4 42.9 57.8
H % CEC 47.9 29.9 31.3 20.8 27.4 0 21 0
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 6 of 11
Al % CEC 10.3 0 0 0 0 0 0 0
eCEC meq/100g
21.1 23.6 22.1 21.6 18.2 18.6 18.4 14.7
K mg/kg 51.8 61.9 69.8 62.7 56.8 37.5 48.1 37.3
Ca mg/kg 117 1276 824 77 546 322 39 90
Mg mg/kg 724 1028 1201 1324 1072 823 959 1033
Texture Silty Clay Silty Clay Silty Clay Silty Clay Medium Clay
Sandy Clay
Light Clay
Light Clay Structure Crumb Crumb Crumb Crumb Crumb Crumb Crumb Crumb
Permeability Slow Slow Slow Slow Slow Slow Slow Slow
Pedal Strength
Moderate Moderate Moderate Moderate Moderate Weak Moderate Weak
Clay content
40 - 50% 40 - 50% 40 - 50% 40 - 50% 40 - 55% 35 - 45% 35 - 40% 35 - 40%
B Horizon Subsoil for Drainage Line 1 and 2
Subsoils in general are heavier in texture than the topsoil and contain a higher percentage of clay.
The subsoils along Drainage Line 1 vary depending on the depth to which the sample was taken. BH1 was taken at
a deeper depth between 340mm – 700mm and is highly acidic, moderately sodic and moderately magnesic. The
strong acidity of the soil has caused aluminium to become available which is toxic to plants. BH6-9 are taken to a
maximum depth of 450mm whereby the soil is not as acidic and hostile although are still highly magnesic, sodic
and magnesic. The subsoils overall have a similar physical appearance and structure. They vary from an orange
brown to dark yellow with some mottling. The soil type is a silty clay with a moderate crumb structure and slow
permeability.
The subsoils along Drainage Line 2 vary considerably in their pH and salinity levels therefore will be described
separately:
BH3 is located midway along the proposed creek line and is at the greatest depth taken at a depth of 250-930mm.
The soil type is a silty clay with a moderate crumb structure and slow permeability. The soil has moderate acidity
and is moderately saline. The cation exchange is highly acidic, highly magnesic and highly sodic.
BH4 is located to the east of the tree, which will remain on the proposed creek line and is taken at a depth of 330-
660mm. The soil type is a medium clay with a moderate crumb structure and slow permeability. The soil has slight
acidity and has desirably low salinity. The cation exchange is highly acidic, highly magnesic and moderately sodic.
BH5 is located in the lowest part of the creek profile, which overlaps the road and was sampled at a depth of 350-
600mm. The soil type belongs to the South Creek landscape and is a sandy clay with a weak crumb structure and
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 7 of 11
slow permeability. The soil has slight alkalinity and is very highly saline. The cation exchange is highly magnesic
and very highly sodic.
C Horizon Subsoil
The soil in the C Horizon becomes more crumbly and changes to a light clay which a moderate crumb structure
and slow permeability. The colour is a darker orange brown with some red mottling. The chemistry is similar at BH3
and BH4 whereby it's slightly to moderately acidic and highly saline. The cation exchange is highly acidic and
highly sodic.
Discussion
In general the topsoils have a slight to strong acidity however have low salinity. They are also variously magnesic
and BH 5 and 6 are sodic. Sodicity in a soils causes the soil to be come highly dispersive in particular at these
levels. Magnesic soils tend to be quite hardsetting particularly on the surface which can cause erosion. The soils
become more saline and hostile with depth by which the dispersive and hardsetting characteristics increase. All
subsoils are magnesic and some are variously sodic.
While these soil landscapes represent some of the better soils of the Cumberland Plain they are fragile and very
easily degraded due to the highly sodic, magnesic and acidic nature of the subsoils.
There are several issues that need to be addressed to prevent detrimental soil issues -
! Hostile sodic and magnesic subsoil - Correct stripping depths so that hostile sodic and magnesic subsoil is
not included in the final recovered topsoil inventory. Acidic, sodic/magnesic subsoil is extremely hostile to
plant growth and we have seen many projects give very poor outcomes and massive losses of plantings
when this material makes its way to the surface.
! Extreme salinity at depth - The salinity and sodicity issues within the B and C horizons and in the
underlying shale makes it important not to allow these to occur at the surface.
! Restablishment of proper A/B/C profiles in in the realigned tributary banks is critical to the establishment of
Cumberland Plain and riparian areas.
! Highly magnesic soils can be hardsetting and dispersive. This can be remedied by using the Ca:Mg ratio
as a guide to boosting the calcium levels. At present calcium is potentially deficient to low and the ratio
ranges between 0.0 to 1.5 whereas the target range to establish new vegetation should be 2.0-3.0.
Gypsum amendments will correct this imbalance.
! High manganese levels. Manganese levels average at 160mg/kg. High manganese levels are indicative of
waterlogging, which is further supported by the mottling which is apparent in most profiles. Provided
profiles are rebuilt properly Cumberland Plan Woodland is tolerant of this.
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 8 of 11
! Very acidic pH. As vegetation develops it acidifies its soil by depleting it of calcium. To counteract the soils
becoming even more severely acidic we recommend small lime additions to allow vegetation to develop
properly.
There is a valuable natural soil resource on this site that, if properly managed, conserved, and reused properly is
suitable for the restoration and creek realignment.
The main limitations for the development will be the dispersive tendencies of the soils alongside the realigned
tribituary.
"Recommendations
Restoration process for Drainage Line 1
The restoration process along Drainage Line 1 will involve treating only the A horizon topsoil. Some of the
ameliorants will work their way into the B Horizon however only in small quantities. Alternatively the A Horizon can
be stripped to treat the B Horizon however this is not deemed necessary for the Cumberland Plain Landscape.
Table 4. Schedule of amelioration requirements.
Soil Type Amelioration Requirement
Gypsum Lime Green Waste
Compost –
Soils for use
with general
tube-stock.
Chipped Hardwood Mulch*
Soils for use with
Cumberland re-vegetation
seeding.
A Horizon
Southern
end (BH 1 and BH2)
1kg/m3 or 100g/m2 4kg/m3 or
400g/m2
10 litres/m2 of compost 60/40 mix, using 60% soil
and 40% hardwood mulch.
Also apply 2 x applications of
20g/m2 of urea
A Horizon
Central and
Northern
end (BH 6 –
BH9)
80kg/m3 or 800g/m2 - 10 litres/m2 of compost 60/40 mix, using 60% soil
and 40% hardwood mulch.
Also apply 2 x applications of
20g/m2 of urea
* The chipped hardwood mulch can be sourced from on-site trees that are to be removed during the upgrade.
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 9 of 11
Soil Stripping and amelioration for Drainage Line 2
The following methodology and amelioration is recommended:
Excavate soil to the depths specified in the Table 5 stripping plan. Stripping operators should observe the following
general guidelines:
• Remove large shrubs and trees first.
• Strip soil and pasture cover to the indicative depth from Table 5.
• Stop stripping if the more orange brown coloured clay subsoil starts showing through regardless of the
indicative depth.
• Stockpile soils from A and B horizon separately in a location where they will not be disturbed during
construction.
• Do not store soil within 8m of the trunk of any retained tree.
• Clearly label the stockpile with its soil horizon using permanent signage.
• Surround stockpiles with silt fencing.
Its imperative during the stripping that the process is carefully supervised to ensure that both weeds and subsoil
are not included with the topsoil.
Table 5. Profile description of Drainage Line 2 for stripping purposes.
Horizon A Horizon B Horizon C
Stripping Depth 250mm 250 - 800mm 800mm+
Colour Medium to dark brown Orange brown Paler orange
Texture Silty loam to silty clay loam Medium clay to sandy clay Light clay and crumbly
Aggregate strength Weak Moderate Weak
Topsoil Reinstatement
Reuse of Site Soils
Table 6 provides a schedule of amelioration requirements each of the soil horizons. These are the basic
amelioration requirements to correct the soil characteristics for Cumberland specific vegetation growth.
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 10 of 11
Table 6. Schedule of amelioration requirements.
Soil Type Amelioration Requirement
Gypsum Lime Green Waste
Compost –
Soils for use with general
tube-stock.
Chipped Hardwood Mulch*
Soils for use with
Cumberland re-vegetation seeding.
A Horizon 8kg/m3 or 800g/m2 4kg/m3 or
400g/m2
10 litres/m2 of compost 60/40 mix, using 60% soil
and 40% hardwood mulch.
Also apply 2 x applications of
20g/m2 of urea
B Horizon 10kg/m3 or
1000g/m2
2 x applications
1kg/m3 or
100g/m2
C Horizon 10kg/m3 or
1000g/m2
2 x applications
1kg/m3 or
200g/m2
- -
* The chipped hardwood mulch can be sourced from on-site trees that are to be removed during the upgrade.
The use of lime will increase the pH levels making the soil less acidic, which will allow for many of the nutrients to
become more available. It is recommended that no additional fertilisers be used as the Cumberland woodland has
a preference for hostile and low nutrient environments. The addition of any further ameliorants will only promote
weed growth and not native growth.
Topsoil re-spreading and amelioration for use in landscape.
The method of application that proves most economical is usually-
1. Spray weed growth on the soil stockpiles with a 1:50 dilution of Roundup or other brand of Glyphosate
concentrate and wait 2 weeks.
2. Remove excess rank weed growth.
3. Place subsoil from the appropriate stockpile. Smooth over B Horizon with grader, consolidate but do not
compact.
4. Place topsoil from the appropriate stockpile to a depth of 250mm and incorporate ameliorants into the top
300mm as specified in Table 5 using chisel ploughs or rotary hoes or alternatively blend into stockpiles
using kg/m3.
5. Apply A Horizon but leave in loose condition for planting, do not consolidate.
6. Incorporate ameliorants into the surface 150mm of the topsoil as specified in Table 5 using chisel ploughs or
rotary hoes or alternatively blend into stockpiles using kg/m3.
Ropes Creek Riparian Corridor Assessment Aecom
July 2015
Page 11 of 11
In summary the soils along Ropes Creek are typical of Cumberland Plain landscape, which are hostile, acidic,
sodic and magnesic. Special care will need to be taken with overall management of stripping and amelioration.
Drainage Line 2 soils are very sodic therefore will easily disperse and care should be taken.
Please feel free to contact our office with any questions you may have.
Sincerely,
SESL Australia.
Chantal Milner
Soil Scientist
Simon Leake
Principal Soil Scientist
References
Bannerman, S.M. and Hazelton, P.A. (1990), Soil Landscapes of the Penrith 1:100 000 Sheet. Soil Conservation
Service of NSW, Sydney.
Mehlich, A. (1984) Mehlich-3 soil test extractant: a modification of Mehlich-2 extractant. Commun. Soil Sci. Plant
Anal. 15(12):1409-1416.
Appendices
Appendix A: Site/ Sampling Map
Appendix B: Profile descriptions
Appendix C: Laboratory Analysis
Appendix D: Site Photos
!
!
!!!
Appendix A Site & Sampling Map
12
6
7 8
9
5
3
4
!
!
Appendix B Profile Descriptions
Oakdale South Riperian CorridorAECOM
July 2015
Bore Hole
Depth (mm) Texture, Structure, Colour Observations
0-340 Medium brown silty loam
340-700Orange/brown medium clay. Some mottling with red and black. Manganese pellets More orange with depth.
BH 2 0-300Silty clay loam, greyish brown. Very wet and surroundngs quite wet. Filled with water @150mm
Drainage Line 1. 15m from creek line.
0-250 Silty brown loam.
250-930Orange brown medium clay with some darker mottling. Becoming a more medium orange with depth.
930-1100Paler orange brown. Soil is more crumbly and less clayey. Black manganese pellets. Some red mottling.
0-330 Medium dull brown, silty clay loam.
330-660 Sudden transition to B horizon. Orange brown clay loam. Red & grey mottling.
660-800 Change in soil, diffuse change.
@800 Soil is more crumbly, mottling of red, grey, back. Darker orangey brown colour.
@1100 Even more crumblier, silty clay.
0-600 Medium dark brown silty clay loam. Wet soil and @350mm becomes even wetter.
600+ Grey wet clay with a few orange mottles.
0-260 Dark brown silty clay loam
260-400 Yellowish dark brown clay. Wet
0-200 Dark brown silty clay loam
200+ Dark yellowish brown clay
0-300 Dark brown silty clay loam
300+ Browney, orange yellow medium clay0-270 Dark brown silty clay loam270+ Orange brown medium clay
BH 3 Drainage Line 2. Midway, greatest depth of proposed creek.
BH4 Drainage Line 2. South side of tree that will remain.
BH 5
BH 1 Drainage Line 1. 5m from creek line, profile dry.
Drainage Line 2. Lowest point in creek profile, overlaps proposed road.
Drainage Line 1
Drainage Line 1. 50m from creek line
BH 9
Darainge Line 1.
Drainage Line 1
BH 6
BH 7
BH 8