NUFLOW NORTHWEST SYDNEY
EDUCATION PRECINCT | NSW DEPARTMENT OF EDUCATION
PROJECT OVERVIEW
Nuflow was engaged to address persistent flooding and drainage issues at a High School, specifically behind C Block near the staff car park. The existing 225mm PVC stormwater line had been compromised by heavy silt deposits, buried pits, and extensive tree root intrusions. These failures caused repeated water pooling during rain events, creating safety hazards and disrupting school operations. The project required a trenchless, long-term solution that could be delivered quickly to minimise disruption on site.
CHALLENGE
- Frequent Flooding – Drainage failures caused flooding and erosion behind C Block, especially after new strip drains were installed.
- Obstructed Pits – Existing stormwater pits were buried and letting large amounts of soil wash into the line.
- Pipe Defects – Rubber ring joints had failed, allowing tree roots to grow inside and deform the pipe.
- Heavy Silt Build-Up – Significant sediment reduced pipe capacity and stormwater flow.
- Tight Timeframes – Works needed to be completed quickly in order to restore safe drainage around the school.
THE SOLUTION
To address the drainage failures and restore the stormwater system, Nuflow implemented a combination of trenchless rehabilitation methods and site improvements:
- Comprehensive Cleaning & CCTV Inspection – The team began with high-pressure jetting (HPJ) to remove heavy silt and root blockages, restoring temporary flow and making the line suitable for inspection. Using CCTV technology, each section of the pipe was mapped and defects were documented, including failed joints and areas of deformation that required structural rehabilitation.
- Pit Excavation & Restoration – A buried stormwater pit was excavated, cleaned, and reinstated. A retaining wall was proposed around the pit to ensure long-term accessibility for future maintenance, preventing a repeat of soil ingress into the system.
- Blueline Relining with Ready Cure – Nuflow’s Blueline system was installed across two key sections of the stormwater line. To minimise disruption, the Ready Cure method was applied, using 65-degree hot water to cure the liner within approximately 2.5 hours instead of the standard 24–36. This fast curing ensured the line was back in service on the same day, keeping the school operational.
- Robotic Cutting & Junction Reinstatement – A junction that had been lined over was reopened using robotic cutting technology, followed by the use of a hydraulic grabber to remove lodged debris. This restored full serviceability of the junction and ensured stormwater could flow through multiple outlets.
- Proposed Surface Drainage Enhancement – To further improve site conditions, the installation of an aggregate drain was recommended along the building slab. The design, 500mm deep and wide, would be filled with blue metal aggregate and finished with decorative stones, providing both effective drainage and an improved site appearance.
THE RESULTS
The rehabilitation works successfully restored the stormwater system servicing the rear of C Block at the High School. The 225mm PVC line, previously compromised by tree root intrusions, failed joints, and heavy silt build-up, was structurally reinforced through Blueline relining. The use of Ready Cure technology enabled the liners to be cured and the line returned to service within a single day, significantly reducing downtime and disruption to school operations. Excavated pits were reinstated and prepared for long-term accessibility, while robotic cutting ensured that critical junctions remained open and fully functional. Final CCTV inspections confirmed that the system is now clear, watertight, and performing as designed, with capacity restored and future intrusion risks minimised. The site was left safe, operational, and better prepared for future storm events, ensuring a reliable and long-term solution for the school community.
NUFLOW’S AGING INFRASTRUCTURE MAINTENANCE AND REHABILITATION
For information on how Nuflow can help maintain and rehabilitate your potable water assets— including pressure main relining, concrete pipeline repairs, and trenchless rehabilitation of critical supply infrastructure—contact our team of specialists. We deliver safe, compliant solutions for even the most complex potable water pipe repair projects.
