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Hinterland Group Inc. Updated August 04, 2026

Pipe Bursting Upsizing — Sewer & Potable (Pre‑Chlorinated Programs)

Introduction

Static pipe bursting with upsizing is a trenchless replacement method that fractures an existing pipe and simultaneously installs a larger‑diameter product pipe along the same alignment. For gravity sewer, it restores structure and increases capacity with minimal disturbance. For potable water, pre‑chlorinated programs pair bursting with disinfected, pressure‑tested mains and controlled cut‑ins to keep outage windows short and water quality compliant.

Where pipe bursting fits in Hinterland’s PRIME delivery

Hinterland Group performs all trenchless technologies in‑house, selecting the most cost‑effective method for each asset and tying execution to its PRIME approach.

  • Pipeline Rehabilitation and Replacement: In‑house bursting and lining methods; method selection via Pipe Rehabilitation and Services.

  • Inspection: Pre/post‑condition verification using vactor/CCTV robotics; see Inspection.

  • Maintenance: Bypass operation, cleaning, and service continuity planning; see Maintenance Plans.

  • Evaluation & Assessment: Risk, hydraulics, and constructability to justify upsizing; see Evaluation and Assessment.

  • Repair & Replacement: In‑house bypass pumping and electrical teams for stations/valves during changeovers; see Repair and Replacement.

Static pipe bursting and upsizing: method and design checkpoints

  • Method basics: A bursting head/expander is pulled by a continuous rod system through the host pipe, fracturing the host and displacing fragments into the surrounding soil envelope while towing in the new product pipe.

  • Upsizing objective: Increase diameter to reduce surcharge (sewer) or improve fire flow and system pressure (water) while reusing alignment to avoid new ROW and major surface impacts.

  • Key engineering checks before upsizing:

  • Geotechnical and cover: soil density, ground water, and depth of burial to manage displacement and heave risk.

  • Adjacent utilities and clearances: protect crossings, services, and near‑surface appurtenances.

  • Alignment and curvature: evaluate sags/bends, service density, and lateral reconnection strategy.

  • Hydraulic justification: confirm target diameter meets level‑of‑service (peak wet weather for sewer; fire flow/pressure for water).

  • Product pipe specification: select pressure‑ or gravity‑rated thermoplastic per utility standard; fusion/weld QA, pulling heads, and bead management planned.

  • Surface/asset protection: pavement, structures, and sensitive corridors (airports, hospitals, downtowns) with vibration/heave monitoring where warranted.

Gravity sewer programs (burst‑to‑upsize)

  • Bypass and continuity: Hinterland designs, installs, and operates in‑house bypass pumping to maintain service and prevent SSOs during bursting and lateral reinstatement.

  • Lateral management: locate/verify active laterals; plan reinstatement cuts or robotic re‑entries; coordinate private connections.

  • QA/QC: Pre‑clean and CCTV; post‑burst CCTV, mandrel or ovality checks where specified, and leakage/air testing per utility standards.

  • Manholes and structures: Adjust inverts/benches; rehabilitate with coatings where corrosion or infiltration is present.

Potable water programs: pre‑chlorinated pipe bursting and cut‑ins

Pre‑chlorinated programs minimize customer downtime and safeguard water quality by disinfecting and testing the new main prior to final tie‑ins.

  • Planning and isolation: Map valves/PRVs, hydrants, and services. Establish temporary supply where needed and schedule customer notices.

  • Pre‑chlorination and testing (conform to utility specs and AWWA practices such as C651): Fill, disinfect, hold as specified, flush, and obtain satisfactory bacteriological results; conduct pressure/leakage testing prior to service transfer.

  • Cut‑ins and changeover: Execute controlled tie‑ins at connection points (tees, crosses, fittings). Transfer services and hydrants to the new main in planned windows to limit outages.

  • Commissioning: Final flushing, water quality verification, valve positioning, and as‑built documentation.

Execution workflow (field‑proven sequence)

1) Survey, utility locates, and constructability review. 2) Cleaning/CCTV (sewer) or shutdown planning (water). 3) Launch/receive pits and shoring. 4) Rod insertion and expander setup. 5) Controlled burst and pull of fused product pipe. 6) Lateral reinstatement (sewer) or service transfers (water). 7) Testing/commissioning. 8) Surface restoration and closeout package.

Sewer vs. potable pre‑chlorinated programs at a glance

Aspect Gravity Sewer (Burst‑to‑Upsize) Potable Water (Pre‑Chlorinated & Cut‑ins)
Service continuity Temporary sewer bypass pumping Maintain supply via staging; short planned outages at cut‑ins
Acceptance testing CCTV, leakage/air tests, mandrel/ovality where specified Pressure/leakage tests; bacteriological compliance per utility/AWWA practices
Customer impact Minimal; traffic control at pits Minimal; notifications and brief tie‑in windows
Appurtenances Laterals, manholes, wet wells Valves, hydrants, services, meters
Primary risks Ground heave, lateral miss, infiltration residuals Water quality non‑conformance, surge/pressure, valve isolation
Key mitigations Geotech review, lateral verification, bypass QA Pre‑chlorination, certified sampling, calibrated pressure tests

Typical use cases (bursting with upsizing)

  • Undersized 1960s–1980s vitrified clay or asbestos‑cement sewers surcharging during wet weather; upsize to restore capacity without full‑width roadway replacement.

  • Cast‑iron water grids with chronic breaks and insufficient fire flow; pre‑chlorinated burst‑and‑replace to larger diameter with staged cut‑ins.

  • Coastal corridors with high water table where open cut is infeasible; static bursting controls vibration and limits dewatering.

  • High‑traffic or venue districts (stadiums, convention centers, airports) requiring night/weekend windows and low community disruption.

Why Hinterland for pipe bursting upsizing

  • All trenchless methods performed in‑house, enabling unbiased method selection and tight quality control across Services.

  • 24/7 emergency readiness with rapid mobilization and documented 15‑minute callback to control risk and outage windows.

  • Integrated bypass pumping, electrical, and field crews to handle stations, panels, valves, and monitoring during changeovers; see Repair and Replacement.

  • Safety leadership with a full‑time OSHA‑certified Safety Manager and an EMR under 0.87, supporting reliable delivery.

  • Southeastern U.S. coverage with Florida HQ and regional deployment; see Markets We Serve.

Getting started