Coolum Beach Coastal Geography & Erosion Study

COOLUM BEACH

Coastal Geography Study

Parts A–E: Observations, Processes & Management

Sunshine Coast, QLD

PART A

Google Earth Observations

Sand Movement & Erosion

Beach narrows near Surf Club after storms

Stumers Creek mouth shifts position between years

Wave Exposure

Northern section (toward Yaroomba) most exposed

Southern end near Point Perry sheltered by headland

Beach Shape Changes

Narrower & steeper after storm years (e.g. 2013)

Wider & gently sloping during recovery periods

PART B: Coastal Health Report

Beach Health Grade

A-

Overall Score

Beach Width & Dunes

Wide dunes act as natural buffers, absorbing wave energy during storms.

Dune vegetation effectively traps windblown sand, facilitating dune growth.

Biodiversity

Coastal plants stabilise sand and persistently help continuous dune growth.

Provides vital habitat, supporting key species and broader ecological resilience.

Human Uses

Recreation (swimming, surfing), SLSC, and a holiday park bring tourism revenue.

Pressures: dune damage from foot traffic, informal paths, litter & wildlife impacts.

Coastal Hazards

The southern end near the Surf Club is identified as the most at-risk zone.

An artificial seawall has replaced the natural protective dune system entirely.

Our Assessment

Moderately Healthy

Strong evidence of robust natural dunes and established biodiversity intact.

Notable vulnerabilities in high-traffic sections require active management.

PART C: Coastal Processes

Dominant Wave Directions

SE swell year-round (dominant)

NE waves in summer/storm season (Nov–Apr)

Storm Types Causing Erosion

Tropical cyclones & east coast lows

Ex-TC Oswald (Jan 2013): 10.5m waves, 3m erosion scarps at Marcoola

Longshore Drift

Waves hit at angle → zigzag sand movement

Net direction: NORTHWARD; ~25,000 m³/yr at Coolum

Storm Impact

Sand washed offshore into sandbanks

Slowly returns during calmer months

Features Interrupting Movement

Point Arkwright & Point Perry headlands shelter from SE swell

Stumers Creek redirects sand; Rock seawall near Surf Club disrupts dune

Most Important Processes

Waves (SE swell + NE storm); Longshore drift northward

Storm surges; Wind rebuilds dunes; Tidal range ~1.36m

Infrastructure at Risk

Coolum SLSC (seawall only); Coastal footpath foundation exposed

Holiday Park 40m behind dune; Vehicle ramp poor condition

Erosion Risk Rating

MODERATE overall; North/central: LOW

Southern Surf Club area: HIGHER; Listed as SEMP priority unit

PART D

Our Management Proposal

MAIN PROBLEM: Southern Surf Club Section

Natural dune replaced by rock seawall ➔ waves scour base ➔ beach narrows. Rising sea levels increase future risk for Holiday Park.

Sand Profiling

Move sand from lower beach to rebuild dune face and protect seawall base. Repeatable after storms.

Dune Revegetation

Plant native coastal species to stabilise dune naturally. Self-maintaining over time.

Advantages

Natural-looking

Cheaper than hard structures

Tourism-friendly

Avoids wave reflection

Environmental Cautions

Machinery may disturb birds

Imported sand must match grain size

Careful species selection

GOAL: Work WITH natural processes, not against them

PART E: Council's Shoreline Erosion Management Plan

Council's Approach

Council prefers <strong style="color: #061123;">LOW-IMPACT</strong> solutions. Strategy = <strong style="color: #061123;">"Monitor, Maintain & Prepare"</strong>. Large engineering solutions are a <strong style="color: #061123;">LAST RESORT</strong>. Several expensive options were rejected in the SEMP as not cost-effective at current risk levels.

Proposed Actions for Coolum Beach (5 Zones)

Most of beach

Sand profiling as needed (shift sand from lower beach to strengthen dune)

Seawall section near Surf Club

Maintain existing wall (good condition, lasts past 2035) + sand profiling in front

Surf Club future upgrade

Only design new wall if Surf Club building is renovated (not a current priority)

Vehicle access ramp

Redesign as operational priority (current one unsafe & inadequate)

Northern areas

Left to manage naturally (good condition, low risk)

KEY TAKEAWAY

Coolum Beach is <strong style="color: #00E5FF;">ONE OF ONLY 15 PRIORITY UNITS</strong> on the whole Sunshine Coast &mdash; meaning it is among the most at-risk beaches and is actively monitored and managed.

KEY TAKEAWAYS

Coolum Beach Coastal Study

Dynamic Beach System

Coolum constantly changes through erosion & recovery cycles driven by waves and longshore drift.

Northward Sand Transport

Up to 25,000 m³ of sand moves northward along the coastline each year.

Storm Risk is Real

Cyclones and east coast lows create waves + storm surge — the most damaging combination.

Soft Engineering is Best

Sand profiling + dune revegetation work with nature, protecting the beach naturally.

Council is Prepared

Coolum is a SEMP Priority Unit with a clear action plan for each beach zone.

Coolum Beach — Sunshine Coast, QLD | Coastal Geography Assignment