Stormwater Drain Repair in Forestville

When a Primary School in Forestville began experiencing extensive stormwater blockages and localised flooding in May 2025, the issue was initially believed to be a simple blockage. Eze-Flow was called in to clear the stormwater system, however after attending site and beginning high-pressure water jetting to clear the multiple lines, it quickly became clear the problem was more complex.

Grates were removed from multiple stormwater pits and heavy debris was manually cleared, including built-up soil, tree roots, and rubbish. One of the main pits was completely filled with compacted soil and roots, requiring excavation by hand before the outlet could be cleared.

Using high-pressure jetting and CCTV drain inspections, we attempted to cleared both upstream and downstream. During this process, a significant amount of debris was removed, including food wrappers, chip packets, and multiple balls lodged throughout the pipeline.

After approximately two hours of continuous jetting, two sections were identified as requiring excavation and repair. CCTV inspection confirmed a collapsed section of pipe, while another section was found to be obstructed by a foreign pipe that had been incorrectly installed into the stormwater line.

• Stormwater pits had not been maintained and were heavily filled with compacted soil, tree roots, and debris, significantly restricting flow 
• Collapsed pipework preventing water movement near the library 
• Cracked and misaligned terracotta pipes 
• Poorly aligned pipe connections catching debris and causing repeat blockages 
• Foreign objects, including multiple tennis balls lodged throughout the pipeline, further restricting flow
• A separate section of the system was completely obstructed by an incorrectly installed pipe connection 

These combined issues were causing ongoing blockages and surface flooding across multiple areas of the school.

A scope of works was prepared to repair the failed sections and restore flow across the stormwater system. Upon approval of the quoted works, Eze-Flow commenced repairs on site.

The first section, located near the third pit, was excavated by breaking through concrete and digging to approximately 1–1.2 metres deep to expose the existing terracotta stormwater line and junctions. The faulty section of pipe was cut out and removed, and the system was rebuilt using new 100mm PVC piping to ensure correct alignment and improved flow. Both pits and outlet drains were reconstructed and reinstated.

Further jetting and CCTV inspections were then carried out to clear remaining obstructions within the system that were not accessible prior to the repair. Additional tree roots, debris, and multiple balls were removed from the pipeline, with the line successfully cleared both upstream and downstream, confirming no further blockages.

To improve future maintenance access, a new inspection opening (IO) was installed on the stormwater line and brought to the surface with a BTS cap.

A second section of the system, located around the reception area near J Block, was also excavated. The team peeled back the existing astroturf and exposed the terracotta stormwater line, where an air conditioning (AC) drain line had been incorrectly inserted into the stormwater pipe, completely obstructing flow.

To resolve this, the incorrectly installed AC line was removed from the main line and reconnected properly by installing a new Y junction, allowing the AC discharge to enter the system without restricting flow. A new pit was then installed below the downpipe outlet and concreted in place to improve drainage and provide better access.

All excavation areas were backfilled, and concrete and surrounding surfaces were reinstated on completion.

Following completion of the works, the stormwater system was fully restored and operating as intended:

• Full flow restored throughout the stormwater system
• Flooding issues across affected areas eliminated
• Blockages caused by roots, debris, and pipe failure removed, including previously inaccessible sections of the system due to the collapsed pipe
• Problem areas around the library and J Block fully resolved
• New inspection points installed for easier ongoing maintenance
• Upgraded PVC pipework providing long-term reliability

The stormwater system is now functioning efficiently and no longer flooding.