MAIN ROADS Western Australia COALFIELDS HIGHWAY PROJECTS ROADSIDE REVEGETATION MANAGEMENT

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

2 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.

3 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.

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5 Coalfields Highway Surveys Environmental assessments for the Coalfields Hwy Project ( 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

6 Project Location Coalfields Hwy 15.9 to SLK

7 Environmental Approvals The project was referred to the Commonwealth Department of the Environment in June DotE determined that assessment under the EPBC act was not warranted in August The Project was referred to the WA Environmental Protection Authority in April 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 Project clearing was conducted under the WA Clearing Regulations and MRWA Internal Process

8 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

9 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

10 Vegetation Placement - Sightlines

11 Topsoil Condition and Management Planning ( Reference MRWA Doc ) 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

12 Existing Vegetation Topsoil management 1* Vegetation Condition Scale 2* Topsoil Condition (Main Roads) (6) (use in topsoil assessment) Topsoil Management (Main Roads). (use in project revegetation planning) Condition Description Condition Description Strategy Description Pristine or nearly so, no Pristine obvious signs of disturbance Excellent (5) Very Good Good (4) (3) Degraded (2) Completely Degraded (1) Vegetation structure intact, disturbance affecting individual species and weeds are non aggressive Well conserved (5) Vegetation structure altered obvious signs of disturbance. Conserved Vegetation structure significantly altered by very obvious signs of multiple disturbances. Retains basic vegetation structure or ability to regenerate Basic vegetation structure severely impacted by disturbance. Scope for regeneration but not to a state approaching good condition without intensive management The structure of the vegetation is no longer intact and the area is completely or almost completely without native species. (4) Partially Conserved (3) Degraded (2) Unsuitable (1) Sections of native vegetation that have no weed invasion and a broad representation of native vegetation Usually fringe vegetation related to well conserved sites that have minor grass infestations Upper storey vegetation intact with some natural understorey but with grass species invading the sites Pasture land or farmland that will require herbicide control to manage weed infestations Weed-dominated sections that include declared plants and other undesirable species Conserve and reuse Treat and reuse Treat and reuse or dispose Dispose Selective clearing and stockpiling of vegetation/topsoil. May be mixed in single operation. Respread on site over finished surfaces. 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. 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 Selective clearing and stockpiling of vegetation/topsoil and disposal off site.

13 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 1 = Unsuitable ( Other - See comment be spoiled off site or Dispose off site to spoil) buried under 500mm class 1, 2 or 3 topsoil) 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

14 Development of Topsoil Plan Management of Weeds and Topsoil

15 Windrowed Topsoil and Mulch mixed and stripped in one operation.

16 Topsoil Respread Plan Replace conserved topsoil onto site

17 Topsoil Respread from stockpiles

18 Landscape Treatment Plan Hamilton Section

19 Planting reports Reports from Project Seed Library Individual Seed Mixes

20 Planting Reports Produces a various cost reports Provides Seed Mixes per lot Provides Total seed requirements Provides tube stock reports for ordering

21 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

22 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.

23 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.

24 Rip and Mound Planting with Covers to protect against Kangaroo grazing

25 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

26 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.

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

28 CO-SM011 Prepared and Bulked Seed Mix

29 Mandurah -Direct Seeding before and after Monitoring Sites established July 2010 Same site July 2012

30 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

31 Coalfields Manufacturing Top Soil

32 Large Project Topsoil and Mulch Stockpiles Advanced planning for topsoil and mulch sites allowed mixing and replacement to be achieved during construction.

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

34 Earthworks Batter Years

35 Hamilton Batter Preparation for Direct Seeding Batter Preparation and Top Soil/Mulch Spread

36 Topsoil Mulch Respread with Batter Chain

37 Seeded Batter 5 Month Growth

38 Mulch & Topsoil Spreading New innovative methods of spreading improved efficiencies Agricultural spreaders Moxi Tippers Swamp Dozers Posi-Tracks Rakes

39 Eco Mulch Spray on Compost / Mulch

40 Sterile Grass and native seed used

41 Offroad - Sand Pit Rehabilitation

42 Offroad - Gravel Pit Rehabilitation

43 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.

44 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

45 QUESTIONS