City of Rockingham. Local Management Practices, Costs and Strategic Coastal Planning

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1 City of Rockingham Local Management Practices, Costs and Strategic Coastal Planning

2 Decision Making Process Considerations Climate Change Response Action Plan Ongoing observations/major Storm events Ongoing Beach Profile Surveys Geomorphology information gained as part of project planning and development Modelling undertaken as part of project planning and development State Planning Policy Coastal Compartments/Sediment Cell Planning Determining adaption outcomes that meet community expectations and Council Policy Community demand and values Local and State Planning Policies

3 City of Rockingham Localities

4 Warnbro Sound Beach Rockingham Foreshore

5 Current Issues and Adaption Methods Renourishment Program Annual costs $200,000 approximately Includes excavation works and stockpiling at Point Peron Stockpiling 15,000m3 per year on average

6 Point Peron Accretion and Garden Island Causeway Interruption of normal coastal processes

7 Sand Trap and Stockpile Point Peron

8 Cost $450,000 Department of Transport Coastal Protection Grant Point Peron Back Beach with GSC Groyne

9 Sand Re-nourishment Michael Road Carpark Erosion and Sand Re-nourishment Hymus Street Re-nourishment Waikiki Foreshore Re-nourishment

10 Sand Re-nourishment Kwinana Beach Top of Dune Dune face High Water Mark - North High Water Mark - South

11 Coastal Erosion Point Peron Erosion as at 9 July 2010 Hymus Street Erosion 2008 Hymus Street Erosion 2009 Michael Road Erosion 2009

12 Storm Events Warnbro Foreshore Erosion 2009 Rockingham Sea Wall View Street Erosion 2009 Rockingham Sea Wall Erosion 2009

13 Coastal Protection - Seawalls Construction of Waikiki Sea Wall Construction of Mersey Point Sea Wall

14 Waikiki Seawall Cost $640,000

15 Coastal Protection Offshore Headlands Kwinana Beach Headlands

16 Kwinana Headlands

17 Warnbro Sound Erosion and Historical Vegetation Lines

18 Beach Access and Car Parking Figure 5.4 Michael Road Car Park Post July 2009 Storm In 2010, MRA completed a coastal assessment of the Michael Road and View Road car parks. A report was provided which gave concept options for providing protection to these car parks (MRA 2010). Several options for coastal protection were investigated which included a geotextile sand container (GSC) seawall or a rock seawall as shown in the following figure.

19 Michael Road Car Park Set Back Options

20 Michael Road Car Park Dune Alignment

21 View Road Foreshore Conceptual Coastal Protection Estimated Cost $720,000

22 Jetties and Boat Ramps Point Peron Boat Launching Facility

23 Recreation Boating Facility Demand Recreation Boating Facilities Study 2009 Rockingham has in excess 10% (DoT Survey 2010) of all registered boats in the Perth Metropolitan area There is a greater proportion of trailered boats in Rockingham Existing ramps experience an extremely high rate of peak demand There is a lack of car parking bays to meet existing demand Expected rise from 4,768 to 6,752 registered boats in Rockingham by 2025

24 Bent Street Navigation Channel Established 2013 Cost $650,000 $75% of cost met through D.o.T Recreational Boating Facility Scheme Grant Modelling of Warnbro Sound Geotech Investigations Accretion due to offshore sand feed Approach to Department of Parks and Wildlife to excavate from Tern Island Navigation Channel 300m long 30m wide and 1.6 2m cd

25 Bent Street Navigation Channel

26 Tern Island Aerial Photographs cont d Tern Island sand bar 1989 Tern Island sand bar 1994 (12/94) Tern Island sand bar 1996A (1/96) Tern Island sand bar 1998A (02/98)

27 Tern Island Aerial Photographs cont d Tern Island sand bar 2000 (12/00) Tern Island sand bar 2005 Tern Island sand bar 2008 Tern Island sand bar 2011

28 Jetties Program Palm Beach Jetty Built 2009 Included Geotechnical Investigations/Wave Modelling $3,200,000 Val Street Jetty Wave Modelling/Geotech Investigations 40m Extension $2,400, metre Reconstruction 2014 $3,800,000

29 Mersey Point Sand Excavation

30 Mersey Point Jetty

31 Mersey Point Jetty and Boardwalk Storm Inundation

32 Mersey Point to Port Kennedy Study Objectives 2012 Present details and projections in relation of littoral sand movement and the impact this along with other elements such as wind and wave action changing sea levels and major storm events have on the current and future boat launching capacity in Warnbro Sound; Identify potential locations for future boat launching facilities within Warnbro Sound and provide layout designs for the development of the boat ramps and the associated infrastructure in these locations; Recommend future development strategies for the sustainable use of Mersey Point including the possible relocation of the existing jetty

33 Why the study was undertaken? Increasing heavy demand for boat launching facilities; Constraints of existing facilities and ramps; Bent Street Navigation Channel Proposal; Mersey Point jetty maintenance and environmental factors; Coastal dynamics resulting in areas of both erosion and accretion; Threats to coastal infrastructure and beach access.

34 Previous studies considered Draft Perth Coastal Planning Strategy (WAPC 2012) Rockingham Foreshore Strategy (Coastwise 2002) Shoalwater Islands Management Plan (DEC 2007) Metropolitan Perth Local Government Areas Recreation Boating Predictions (DPI 2007) and Perth Recreation Boating Facilities Study 2008 (2009) Bent Street Navigational Channel Referral Document Rockingham Foreshore Strategy ( 2012 )

35 Study Methodology Considered previous and current studies and coastal process research undertaken for these waters. Review of coastal process on beaches from Shoalwater to Port Kennedy Wind and wave action / impact possible sea level rise impacts Sediment transport Critical erosion/accretion areas Condition report of existing infrastructure Ongoing maintenance requirements Infrastructure replacement options

36 Beach Profile Survey

37 Beach Profile Survey

38 2G WAVE Spatial Plot of Typical Swell

39 Coastal Environment Geology and Geomorphology

40 Climate Change

41 2010 Population - 101,800 To increase by about 3,000pa 2021 Population Forecast - 136, Population Forecast - 164, Baldivis Population Forecast - 41,000 (Currently 12,000)

42 Planning Precincts along Warnbro Sound

43 Precinct Type & Character Precinct Intensity Shoalwater Built up- residential Low Moderate Major Issues & Planning Considerations Shoalwater Islands Marine Park Physical coastal processes setback encroaches onto residential land and active coastal management may be required Safety Bay Built up- Mixed use Moderate Shoalwater Islands Marine Park Setback requirements and erosion at ends of seawalls Physical coastal processes setback encroaches onto urban and residential zoned land Southern aspect unique on Perth coast Land uses & Features to be Promoted Residential development Active recreation Conservation around islands Café and change rooms along foreshore Active use of foreshore area Cafes, grassed areas, BBQs and picnic areas Dual use path Residential development Small mixed use area Boat Ramp Recommendations Further investigation into coastal management requirements of areas which lie in coastal setback distance Detailed assessment of overtopping strength, durability of Mersey Point Seawall Protection & recognition of Aboriginal heritage site Develop & implement a coastal management plan Waikiki Built up- Residential with mixed use focus Moderate Shoalwater Islands Marine Park Physical coastal processes setback encroaches onto residential land and active coastal management may be required Residential with mixed use focus Retail/office/entertainment Tourism & recreation Family uses with relaxed feel Shade, BBQs, picnic areas Water ski area Dog beach Develop & implement a coastal management plan North Warnbro Open space Passive recreation - Shoalwater Islands Marine Park Physical coastal processes setback encroaches onto developed land Family uses with relaxed feel Sport & recreation Dog Beach Picnic & BBQ areas Residential Car parks & paths Further investigation to determine appropriate management measures Develop & implement a coastal management plan South Warnbro Built up Residential Low Moderate Shoalwater Islands Marine Park Physical coastal processes setback Encroaches onto developed land and active coastal management may be required Foreshore erosion threatening dunes and adjacent road Residential Passive recreation Car parks & paths Designated water ski take off area Low levels of access Further investigation to determine appropriate management measures Develop & implement a coastal management plan

44 Zoning Scheme of the Shoalwater Islands Marine Park

45 Existing Coastal Process Considerations Dynamic Coastline with areas of erosion and accretion and north/south facing beaches Existing hot spots being actively monitored Some wave protection from the Murray Reef System in Warnbro Sound Break in the reef allowing sand infill to be deposited at northern and southern ends of Warnbro Sound

46 Coastal Process Considerations Limited opportunities for additional boat launching and jetty facilities along the coast Garden Island causeway disrupting sand movement along coast Variety of coastal types from sandy beaches to limestone reef Possible future erosion and inundation threats to established public infrastructure and private housing

47 Coastal Management Plan Considerations Consider findings of PNP and CSCA work Consider State Planning Policy Objectives and requirements Consider Shoalwater Island Marine Park Management Plan impacts Determine the community values, objectives, strategic directions for the coast

48 Coastal Management Plan Considerations Local structure plan and / or town planning scheme considerations; Include strategic direction, climate change vulnerability over 100 years and management activities/actions over next 5 10 years in one document Document existing and future coastal infrastructure Collate information and data to be able to provide this information in RFT/RFQ s

49 Coastal Management Plan Proposal Consideration of documented risks of coastal erosion and inundation hazards now? And over next several decades (timeframe of CMP) Gap analysis of CoR coast for coastal data and information and actions to fill gaps Shoreline Data Wave Modelling Geotech Investigations Wider influences (e.g. Leeuwin Current) Climate Change Response and adaption strategies Use CSCA values and assets study to document environmental, heritage and recreational values/ecosystem services of the coast List existing coastal protection structures (seawalls, groynes, breakwaters) and detail current renourishment programs

50 Coastal Management Plan Proposal Use of sediment cell hierarchy in terms of space and time scales Identify stakeholders for each section of coast Consider appropriateness of future developments on the coast Recommend baseline and ongoing coastal zone monitoring/datacollection required for CoR coast by section, and generally, over next 3-5 years Document legislative framework for coastal planning and management in CoR area Present understanding of coastal processes Review and document literature associated with coastal processes, risk management and adaption process

51 Strategy for Coastal Protection and Infrastructure Outcome Sought To develop comprehensive Coastal Management and Infrastructure Plans, for the City of Rockingham s 26km of coastline, that provides a strategic approach to the protection of the coastline, and the development of future coastal infrastructure. These coastal management plans are to:- Identify creeping change Areas threatened as a result of extreme events Define what is considered to be a successful adaption process Prioritise future engineering solutions if required to protect the coast and associated infrastructure. Justify expenditure Further develop existing concept plans for the possible future development of coastal infrastructure and the upgrading/expansion of existing facilities, to meet forecast demand for boat launching facilities, jetties, car parking and beach access. Identify opportunities for the City to develop a joint management approach with private and/or State agencies, towards the protection of certain areas of the coast, and present strategies that will facilitate and foster these joint management approaches. Develop outcomes that are monitored/reviewed

52 Thank you