Home » Case Study: Restoring Stormwater Capacity — Gold Coast Seafront Residence

Case Study: Restoring Stormwater Capacity — Gold Coast Seafront Residence

Project Snapshot

  • Client: Architect‑designed beachfront home in Main Beach, QLD
  • Problem: Garden floods after every summer downpour; pooling undermining retaining wall
  • Pipe Network: 90 mm PVC stormwater line, 32 m long, connected to kerb outlet
  • Turnaround: 2‑hour diagnostic, 1 day remediation
  • Tech Utilised: CCTV crawler, hydro‑excavation, sectional pipe bursting, HD‑PE pull‑through liner

1. The Challenge

1.1 Visible Symptoms

  • Knee‑deep puddles forming within 20 minutes of rainfall
  • Saltwater staining along basement blockwork
  • Mosquito breeding reports from neighbours

1.2 Investigation Findings

Sequential CCTV passes exposed:

  1. Sand Intrusion: 18 m section half‑filled with fine coastal sand.
  2. PVC Deformation: Crushed pipe at 14 m mark due to previous landscaping works.
  3. Corroded Kerb Outlet: Cast‑iron flap permanently stuck closed.

“A beachfront block amplifies every drainage flaw—salt, sand and shifting ground give pipes a hard life.”
— Principal Technician, SEQ Blocked Drains


2. Solution Strategy

Phase 1 – Immediate Flow Restoration

  • Hydro‑Vac Excavation: Safe exposure of buried line at failure point.
  • High‑Volume Flush: 75 mm sand jet nozzle, 60 L/min, cleared 25 kg of sand.

Phase 2 – Structural Renewal

  1. Sectional Pipe Bursting – 8 m crushed segment replaced with 100 mm HD‑PE (SDR 17) without trenching through manicured lawn.
  2. Pull‑Through Liner – Seamless epoxy‑impregnated liner installed from burst section to kerb, ensuring uniform diameter and salt‑resistance.
  3. Kerb Outlet Upgrade – Swapped corroded flap for UV‑stabilised PVC grate and flap combo.

2.1 Equipment & Materials

AssetFunctionCore Spec
CCTV Storm CrawlerLocate sand levels & deformation23 mm camera head, self‑levelling
Hydro‑Vac UnitNon‑destructive digging4200 L/min vacuum capacity
Pipe Bursting RigReplace crushed PVC30 kN pulling force
HD‑PE PipeNew carrier line100 mm Ø, 50‑year design life
Epoxy LinerCorrosion barrier4 mm wall, CIPP‑certified