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 - YP East

Point Turton

Point Turton - YP East

Moonta Bay (Simms Cove)

P. Zadow

• 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.)

Coastal Erosion Protection Strategies

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

• 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

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.

• 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

Unauthorised works

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.

Res

ZoneCoastal Zone

Landward

Boundary

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…….?