Coastal Erosion Protection Strategies Private Works on Public Land Arron Broom Coastal Policy Planner Coastal Management Branch, SA DEW Delegate for the Coast Protection Board
2016 Storm Events SA experienced 3 major storm events in 2016 9 May 2016 - Highest recorded water level at Outer Harbor tide gauge since records began Further statistical analysis required to categorise the 9 May event (e.g. 1:50, 1:100 ARI) Regional communities impacted the most, particularly on Yorke Peninsula
Pine Point
Hardwicke Bay
Point Turton Point Turton - YP East
Moonta Bay (Simms Cove) Point Turton - YP East P. Zadow
Coastal Erosion Protection Strategies Numerous requests for meetings by concerned landowners, communities and Council staff across YP Advice sought on coastal erosion protection strategies (not all protection strategies equate to seawalls) Increase in development applications for seawalls on YP last line of defence Most applications have been for private seawalls on public land the focus of this presentation
Coastal Erosion Protection Strategies Private seawalls on public land (the beach) can be a contentious and challenging project for the proponent - usually a landowner or representative group with no experience in coastal management Also a challenging assessment process for the Coast Protection Board (CPB) The CPB has power of direction over seawalls in a coastal zone Early expert advice is important - to guide solutions and outline approval processes (planning, tenure etc.)
Point Turton - Town hall meeting (25 May 2016)
Extent of works required, approx. 420m long High erosion hazard risk Seawall the preferred solution Community Reaction Thank you Who Pays?
Project Challenges While on public land, the works are designed to protect private property only. The landowner/s pays DEW is under no obligation to protect Crown land CPB provides grant funding for adaptation strategies and implementation of protection works where there is public benefit Cost to construct, initial estimate $40-50,000.00 per landholder At this point, without effective leadership and community buy in, projects often fail
Project Challenges Government cannot compel communities to act - However, without protection, new dwellings may not be permitted. A representative landowner or group needs to coordinate other landowners, seek agreement to contribute funds, manage consultants, navigate the approval processes, and ensure any conditions of approval are implemented. At the Pt Turton town hall meeting, leadership emerged. A Shack Owners Group formed. A development application was submitted. But challenges soon emerged.
Project Challenges Some landowners unwilling or unable to contribute funds The Shack Owners Group requested funding from YP Council in the form of a fixed term, fixed low interest loan to be secured via a special rate on the subject properties. The request was successful. As a group, borrowings totalled $181, 643 of a project total of $514,249. The funding mechanism was critical - it enabled the project to commence, removing the potential for unauthorised works.
Unauthorised works Potential to exacerbate erosion on adjacent property Impact on foreshore amenity Public safety risk Risk of failure Compromise settlement wide adaptation strategies and redevelopment potential
Coast Protection Board - Assessment Considerations Designed by a suitably qualified coastal engineer A seawall to protect residential development should minimise erosion hazard risks associated with a major storm event with an allowance for 0.3m metres of sea level rise The wall should be capable of being upgraded to accommodate further sea level rise of 0.7 metres
CPB Assessment Considerations The design should determine how many properties are to be included, whether staged works are practical and preferable Avoid gaps in the seawall that may lead to unacceptable end effects i.e. localised scouring of adjacent land (important in this case) Maintain a consistent material design
CPB Assessment Considerations Minimise development of public land Consider impacts on natural processes and ecosystems (e.g. the placement and timing of construction might need to consider the nesting habitat and breeding cycle of particular shorebirds) Landscape the adjacent landform. This can soften the engineering works (to an extent), add biodiversity value and assist stabilise the escarpment
CPB had no objection, directed conditions Council approved the development application Each adjacent owner subject to a Crown land licence Project a relative success but a complex process for landowners Point Turton Seawall under construction, Sep 2017
Moonta Bay Cliff Erosion
Moonta Bay - Cliff Erosion Cliff Top Stability Study determined the risk (caused by run off, wind and wave attack) and recommended conceptual mitigation options including seawalls No detailed and coordinated protection strategy to protect private property at local level Landowners proposed a series of seawalls in the Residential Zone. No formal referral to CPB. CPB have encouraged Council to take a more strategic approach. Coastal Zone Landward Boundary Res Zone
Can (or should) Government do more? DEW/CPB to continue engaging with communities, provide preliminary coastal planning advice, distribute guidelines, factsheets etc CPB has introduced a modest seed funding grant scheme (design component only) incentive for coordinated whole of settlement erosion protection strategies to protect private property Local Government to consider applying special rates to enable projects to commence without total landowner buy in (YP Council may have set a precedent in SA) Ultimately, State Government cannot compel all Councils and landowners to act
Can Government do more: SA Planning Reform: 1. Ultimately, ensure appropriate planning and design codes are in place to avoid and minimise risk, and ensure development applications are referred to the CPB 2. Investigate potential for infrastructure scheme coordinators under the new Planning, Development and Infrastructure Act 2016
Questions.?