MAIN ROADS Western Australia COALFIELDS HIGHWAY PROJECTS ROADSIDE REVEGETATION MANAGEMENT Presentation - South West Region - Alan Grist, Project Manager, Environment (November 2015)

Protecting and enhancing the environmental values of road reserves Minimising the impact on the natural environment of roads and road use; & Conserving natural resources and minimising energy consumption and waste.

Aims for MRWA Roadside Revegtation CONSERVATION OF INDIGENOUS VEGETATION • Assist in the development of construction and maintenance techniques

to ensure the conservation of existing natural vegetation. • Manage roadside burning and roadside fuel reduction programmes. • Implement Main Roads Dieback Policy. • Management of rare and endangered flora (DRF) and fauna with DEC. ROADSIDE REHABILITATION • Vegetation programmes to enhance roadside verges and borrow areas

during and following construction. • Ensure all rehabilitation and conservation aspects are carried out in

accordance with Main Roads policy and accepted standards. • Document treatment methods and report on results.

Coalfields Highway Surveys

Environmental assessments for the Coalfields Hwy Project (15.9-26.3 SLK) commenced in spring 2010 during the alignment selection process. Surveys completed over the course of project development included: • Flora and vegetation Assessment • Fauna Survey • Aboriginal Heritage Survey • Follow up Rare flora Survey • Project clearing was determined to be 25 ha of native vegetation • Dieback Study and Management Plan

• Project Location

• Coalfields Hwy • 15.9 to 26.30 SLK

Environmental Approvals

• The project was referred to the Commonwealth Department of the Environment in June 2013. DotE determined that assessment under the EPBC act was not warranted in August 2013.

• The Project was referred to the WA Environmental Protection Authority in April 2013. In July 2013 the EPA determined that the Project did not warrant formal assessment under the WA Environmental Protection Act

• The Approvals for clearing and environmental offset were approved in July 2014.

• Project clearing was conducted under the WA Clearing Regulations and MRWA Internal Process

PROJECT PLANNING • Landscape planning by the MRWA Landscape Manager

• MRWA have developed software from “Archibus and CAD SIS” to

document landscape works and implementation requirements • Topsoil Management Planning completed and implemented in

accordance with project plans

• Seed collection and plant propagation requirements identified early (2014) to obtain resources required

• Vision Zero requirements and Recovery zones included in design

criteria. New safety requirements make conservation of existing roadside vegetation more challenging

Design considerations for Vegetation Placement and Clear Zones

Any woody species likely to exceed 150 mm diameter, or 1 m height in table drain and up to 1 m up backslope

Any woody species likely to exceed 150 mm diameter, or 3 m height within 14 m of shoulder edge

6m Minimum Overhead Clearance

Vegetation Placement - Sightlines

Topsoil Condition and Management Planning ( Reference MRWA Doc 6707-053 )

• Topsoil Classification – Utilise a spreadsheet to document this into condition and value, prior to stripping, mixing or placement

• Considerations of Dieback Free sites to protect area • Precautions for working within Dieback Infected sites

• Utilisation of existing natural resources – Mulch,

Manufactured soil mixes • Remove unsuitable materials • Conserve and protect valuable topsoils

Existing Vegetation Topsoil management 1* Vegetation Condition Scale

2* Topsoil Condition (Main Roads) (use in topsoil assessment)

Topsoil Management (Main Roads). (use in project revegetation planning)

Condition Description Condition Description Strategy Description

Pristine

(6)

Pristine or nearly so, no obvious signs of disturbance

Well conserved

(5)

Sections of native vegetation that have no weed invasion and a broad representation of native vegetation

Conserve and reuse

Selective clearing and stockpiling of vegetation/topsoil. May be mixed in single operation. Respread on site over finished surfaces.

Excellent (5)

Vegetation structure intact, disturbance affecting individual species and weeds are non aggressive

Very Good

(4)

Vegetation structure altered obvious signs of disturbance. Conserved

(4)

Usually fringe vegetation related to well conserved sites that have minor grass infestations

Good

(3)

Vegetation structure significantly altered by very obvious signs of multiple disturbances. Retains basic vegetation structure or ability to regenerate

Partially Conserved

(3)

Upper storey vegetation intact with some natural understorey but with grass species invading the sites

Treat and reuse

Selective clearing and stockpiling of chipped (or slashed) vegetation and topsoil. May be mixed in single operation Weed control as needed. Respread on site over finished surfaces.

Degraded

(2)

Basic vegetation structure severely impacted by disturbance. Scope for regeneration but not to a state approaching good condition without intensive management

Degraded

(2)

Pasture land or farmland that will require herbicide control to manage weed infestations

Treat and reuse or dispose

Selective clearing and stockpiling of chipped (or slashed) vegetation and topsoil. May be mixed in single operation. Weed control program. May be respread in selected areas. May be buried on site

Completely Degraded

(1)

The structure of the vegetation is no longer intact and the area is completely or almost completely without native species.

Unsuitable

(1)

Weed-dominated sections that include declared plants and other undesirable species

Dispose Selective clearing and stockpiling of vegetation/topsoil and disposal off site.

Topsoil Condition Spreadsheet

TOPSOIL STRIP and TOPSOIL MULCH RESPREAD MANAGEMENT STRATEGY (Check description describes what is being planned - eg Strip or Respread or both combind)

Trim File -

ADD PROJECT TITLE HERE

Classification key ( Aligns with Vegetation

Condition Rating)

5 = Well Conserved 4 = Conserved 3 = Partially Conserved 2 = Degraded ( To be spoiled off site or

buried under 500mm class 1, 2 or

3 topsoil)

1 = Unsuitable ( Dispose off site to spoil)

Other - See comment Drawing References

Item # Chainage Start

Chainage Finish

Distance LHS Classification LHS Management Actions Proposed Direct Seed Area - m2

RHS Classification RHS Management Actions Proposed

Direct Seed Area m2

General Comments

Development of Topsoil Plan – Management of Weeds and Topsoil

Windrowed Topsoil and Mulch mixed and stripped in one operation.

Topsoil Respread Plan – Replace conserved topsoil onto site

Topsoil Respread from stockpiles

Landscape Treatment Plan – Hamilton Section

Planting reports

• Reports from Project Seed Library

• Individual Seed Mixes

Planting Reports

• Produces a various cost reports

• Provides Seed Mixes per lot

• Provides Total seed requirements

• Provides tube stock reports for ordering

Landscape Works

• Propagation native seedlings – Order well in advance

• Collection of native seed – Define requirements and availability

• Soil preparation – Site specific, scalping, rip-mound, or rip-furrow

• Application of pre mixed seed mixes – Direct seeding

• Planting – Hand or machine planting, auger plant.

• Maintenance and infill planting continued in following years

• Weed Control – Pest Control

GENERAL LANDSCAPE NOTES

• 1.1 Refer to the schedules in the specification for hold points, composition of plant and seed mixes.

• 1.2 Service locations are only indicative and must not be used for excavation. Accurate service locations should be identified prior to excavation.

• 1.3 Trees that will develop trunks larger than 100mm shall not be planted closer than 11m from the painted edge line or driving edge of the road or closer than 3m from adjacent property boundaries and fence lines.

• 1.4 Shrubs and ground covers shall not be planted closer than 6m from the painted edge line or driving edge of the road or closer than 3m from adjacent property boundaries or fence lines.

• 1.5 All planting to be located to preserve the visibility and integrity of road signs and intersections sight lines.

RIP MOUND AND PLANT - RMP

• 2.1 Apply herbicide control of Glyphosphate 360 at 3L/Ha. • 2.2 Site preparation by rotary hoeing along rip lines. • 2.3 Rip to a min depth of 500mm and mound to a min height of

300mm. • 2.4 Apply Glyphosphate 360 at a rate of 2L/Ha and Simazine

500 at a rate of 4L/Ha prior to mulch application. • 2.5 Apply natural mulch material evenly over mounds to achieve

a minimum cover of 50mm. • 2.6 Plant seedlings in the centre of the mounds directly above

the rip line, approximately 2.0m apart or as specified by the relative plans and place a fertiliser tablet 200mm deep and 200mm away from the seedling.

•

Rip and Mound Planting with Covers to protect against Kangaroo grazing

AUGER PLANTING

• 3.1 Apply herbicide control of Glyphosphate 360 at and 3L/Ha Simazine 500 at a rate of 4L/Ha prior to mulch application.

• 3.2 Auger individual seedling holes with a CSIRO auger to a minimum depth of 500mm and approximately 3m centre spaces.

• 3.3 Apply natural mulch material evenly over the site to achieve 50-70mm cover.

• 3.4 Plant seedling into prepared holes and place fertiliser tablet 200mm deep and 200mm away from each seedling.

• 3.5 Use tree guards if required to define location and to protect seedling

DIRECT SEEDING – Premixed Topsoil and Mulched sites

• 4.1 Apply herbicide control of Glyphosate 360 at 3L/Ha if required. • 4.2 Evenly spread seed at the specified application rate (Normally 4 Kg/Ha)

evenly across entire site directly after topsoil / mulch respreading. • 4.3 Apply broad spectrum fertilizer at 150Kg/Ha (To be approved prior to

application - suggest Horticultural special / agras # 3) . • 4.4 Lightly harrow or chain the site to incorporate seed into the top soil

horizons. • Note – Sites with no prior topsoil/mulch respread, additional soil preparation is

required prior to application of seed. • 4.5 On compacted sites, Rip to a minimum depth of 500mm with minimum 1m

spacings across the entire site. • 4.6 For non mulched sites, apply natural mulch material evenly over the site to

achieve 50-70mm cover. • 4.7 Rotary hoe the area to incorporate mulch into soil and proceed as per 3.3.

DIRECT SEEDING

Direct Seeding in progress. Seeding works applied by hand or by using mechanical spreaders for optimum distribution and consistency.

CO-SM011 Prepared and Bulked Seed Mix

Mandurah -Direct Seeding before and after

Monitoring Sites established July 2010

Same site July 2012

Mulch, Compost and Topsoil Mixing

• Stockpile in area that can be kept weed free • Use weed free topsoil or conserved topsoil • Import compost to improve soil • Identify opportunities to use weed free unsuitable • Manage mixing process • Monitor temperatures • Protect from weed infestation • Spread by one of the various

options

Coalfields Manufacturing Top Soil

0

10

20

30

40

50

60

70

Large Project Topsoil and Mulch Stockpiles

Advanced planning for topsoil and mulch sites allowed mixing and replacement to be achieved during construction.

Earthworks Stepped Batters 2013 Batters stepped to allow topsoil to be retained on batter. Benefits - Provides improved stabilisation - Improves vegetation establishment - Minimise scour

Earthworks Batter 2015 – 2 Years

Hamilton Batter Preparation for Direct Seeding

• Batter Preparation and Top Soil/Mulch Spread

Topsoil Mulch Respread with Batter Chain

Seeded Batter 5 Month Growth

Mulch & Topsoil Spreading

• New innovative methods of spreading improved efficiencies

• Agricultural spreaders • Moxi Tippers • Swamp Dozers • Posi-Tracks • Rakes

Eco Mulch – Spray on Compost / Mulch

Sterile Grass and native seed used

Offroad - Sand Pit Rehabilitation

Offroad - Gravel Pit Rehabilitation

Avoiding Erosion and Silting

Runoff from projects can cause erosion and the material eroded can create a silting problem once the runoff reaches a receiving water source. MRWA’s practices to reduce the issues involve: • Minimizing the amount of clearing and disturbance taking place • Control discharge and sedimentation caused by dewatering

activities • Minimize the wastewater from project activities • Ensure runoff is not entering Environmentally Sensitive Areas

(ESAs) • Control erosion and runoff from construction activities • Stabilize site as soon as possible.

Weed Control

The following are practices employed by MRWA to minimize weeds: • Identify weeds pre-operation, plan and start weed management

programs • Control declared plants as required by Agriculture WA’s

regulations • Minimize site disturbance • Ensure equipment and vehicles kept weed free when moving

on/off site • Manage movement of topsoil

QUESTIONS