Water Reservoir/Infrastructure Maintenance
Project Overview
Indianic was contracted to complete works at Water Corporation’s major water catchment dams in the Darling Range—Mundaring, Serpentine, Wungong, and Victoria.
Our team executed a multi-site program to remove, and temporarily blank large-capacity raw water intake lines connected to inspection and water monitoring towers.
The works were delivered under strict operational constraints to maintain reservoir integrity and public water supply continuity.
Given intake depths exceeding 40 meters, the program combined advanced commercial diving, confined-space protocols within tower structures, and on-site hyperbaric support to manage complex risk, schedule, and quality requirements.
Services Provided
- Detailed dive planning, risk assessment, and method development for deep, cold, low-visibility environments
- Commercial diving operations >40 m, including mixed-gas capability and staged decompression
- Mechanical isolation, removal, and blanking of large-diameter intake penetrations
- Fabrication and installation of engineered blind flanges and custom blanking plates
- Non-destructive testing (NDT) and leak verification (hydrostatic checks and visual confirmation)
- Deployment and operation of an in-house mobile decompression chamber for on-site hyperbaric support
- Cathodic protection services which included installing cathodic anodes and Diver-cote surface protection.
- Environmental controls for turbidity, biofouling management, and debris containment
- Comprehensive QA/QC documentation, as-built records, and handover packs
The Challenge
Work fronts were submerged at depths >40 m with near-zero visibility, elevated hydrostatic pressures, and water temperatures that posed hypothermia risks and increased decompression obligations.
Access around intake structures was constrained by tower geometry, legacy fixtures, and biofouling.
Strict operational and environmental requirements demanded zero unplanned discharge, no adverse impact to reservoir quality, and no interruption to supply.
Variable reservoir levels and weather windows further complicated sequencing and diver exposure management.
The Solution
Indianic engineered site-specific dive plans with hazard registers aligned to AS/NZS 2299 and client procedures, adopting a mixed-gas profile and staged decompression to control inert gas loading.
Custom lifting frames and rigging were designed for precise intake component handling within tight tolerances.
Blanking hardware was pre-fabricated and trial-fitted on mock-ups, which were corrosion-protected to suit the dam environment.
Our mobile decompression chamber was established at each site on emergency standby to enable immediate post-dive treatment, and schedule resilience.
Real-time topside communications, umbilical management, and redundant lighting/camera systems supported accurate placements despite low visibility.
Turbidity curtains and vacuum recovery minimised plume and debris migration.
Outcome
Maintenance of all four dam sites was completed safely, on schedule, and without impact to potable water quality or supply continuity.
Intakes were successfully isolated with verified leak-tightness, extending asset life and simplifying future maintenance requirements.
The integrated hyperbaric capability reduced decompression risk and minimised downtime between dives, improving productivity across multi-site logistics.
Water Corporation received full QA/QC portfolio—including NDT records, torque logs, coating reports, and as-built drawings—providing traceability and assurance for long-term operation.
This project demonstrates our capability for delivering high-risk underwater works on critical infrastructure with zero harm and strong technical confidence.
