Pipe burst, 4" cast iron → 6" HDPE, in November snow.

§ I · Diagnosis

Survey performed by Marie Knapp and Seth Burczyk, 11 a.m. Friday 15 November 2024, after the customer reported repeated backups across two weeks and a final standing-water event the previous evening. CCTV crawler entered at the basement floor cleanout; encountered standing water 6 in. deep at sta. 0+04 (foundation step) and 4 in. deep at intermittent points along the run. Survey completed in two passes after partial cabling.

Original lateral material: 4-in. cast iron (1894 install per Allentown Historic District building survey records¹; documented at the Buffalo Erie County Historical Society²). Run length 38 ft, foundation to city main on Mariner Street. PACP-coded defects:

• Sta. 0+12 — JOL · severity 4 · joint offset ≈ 28% (vertical, downward)
• Sta. 0+19 — JOM · severity 3 · joint offset ≈ 18% (lateral, north)
• Sta. 0+27 — JOM · severity 3 · joint offset ≈ 16% (vertical, downward)
• Sta. 0+34 — CL · severity 4 · longitudinal crack 14 in. at the curb stop, with active infiltration
• Throughout — DAE · severity 2 · attached encrustation (typical of cast iron 90+ years in service)

Two of the three offsets exceeded CIPP tolerance. The longitudinal crack at the curb stop was admitting groundwater on every survey-day flush, indicating active failure. The cumulative DAE encrustation reduced effective ID from nominal 4 in. to about 3.25 in. — the pipe was both structurally compromised and hydraulically undersized. CIPP would have been a 4"→3.7" reduction; that is not a pipe.

§ II · Recommendation

Pipe burst (RKT-MTH-02), upsizing 4-in. cast iron to 6-in. SDR-17 HDPE. The customer needed a pipe that would (a) replace the failed structural condition entirely, (b) restore proper hydraulic capacity for a two-bath two-occupant household, and (c) provide a 50-year design horizon with no further intervention.

§ III · Execution

Job day: Monday 18 November 2024. Crew: Dani Okonkwo (lead operator), Al Reuter (basement-side connections), Marie Knapp (foreman/permit), Linda Pham (operations). Public utility locate via Dig Safely NY ticket #2024-11-118-A executed 11/15. Private locate by GPRS Buffalo confirmed no parallel utilities within the burst envelope.

1. 7:00 — Arrived on site. Snow had begun overnight, 1 inch on the ground.
2. 7:30 — Excavation began. Curb-side pit (4×4×6 ft) on Mariner Street, basement-side pit (4×4×7 ft) at the foundation. Pits shored per OSHA Subpart P. Both pits hand-dug below 24 in.
3. 9:45 — Both pits open, host pipe exposed at both ends. Cable fed through the host using the CCTV tow-hook method.
4. 10:30 — TRIC Tools M-100 set up at curb-side pit. Bursting head (cast-iron-cutting wheels) attached. New 38-ft length of 6-in. SDR-17 HDPE staged behind the head, fusion-welded inside the basement-side pit by Al Reuter.
5. 11:00 — Burst begun. Pulling force averaged 14 tons; max 18 tons at a single bell. Total pull duration 38 minutes for 38 feet.
6. 11:45 — Burst complete; new HDPE in place. Visible ground heave above the pipe approximately 1.5 in. at the surface, dissipating to baseline within 4 ft laterally.
7. 12:30 — Connections made. Basement side: HDPE-to-cast-iron transition with Husky 3000 no-hub coupling, new 6-in. cleanout to grade. Curb side: fusion to existing tap stub at city main, tap-saddle replacement coordinated with on-site BSA inspector (M. Yacoub).
8. 2:00 — Pressure test 100 psi for 30 min, no drop. Backfill curb-side pit; basement-side pit backfilled by 2:45.
9. 3:30 — Post-install verification CCTV, full run. Backfill complete, surface restored to as-found condition (asphalt patch on Mariner Street scheduled for 11/26 by BSA street-cut crew, included in our permit fee).
10. 4:30 — BSA permit closeout signed by inspector Yacoub. Customer back in service.

§ IV · Cost & warranty

Pipe burst, 38 ft, 4"→6" HDPE, including pits, fusion, and connections	$9,400
Private utility locate (GPRS Buffalo)	$320
BSA permit fee + street-cut restoration assessment	$485
Snow-day labor premium (3 hrs)	$120
Subtotal	$10,325
NYS sales tax (8.75%)	$875
Total turnkey	$11,200

1-year workmanship warranty. HDPE line carries 50-year design life under PPI TR-3.

§ V · Follow-up · 12 months · 19 November 2025

Follow-up CCTV performed by Seth Burczyk one year after install. Bore continuous, joints (none — fusion-welded HDPE has no joints), surface restoration intact, no visible re-settlement at either pit. Customer reported zero backup events in the intervening 12 months, including through the heavy thaw of March 2025 that produced surcharge events on multiple Allentown streets. The Mariner Street BSA street-cut patch was inspected by the city's DPW in March 2025 and re-patched at city expense (typical first-winter re-patch).

Closing note from Marie: the snow was incidental. Buffalo construction crews work through snow because Buffalo construction would never happen otherwise. The notable engineering item on this dossier is the cast-iron-to-HDPE transition: we used a Husky 3000 no-hub coupling because that's the right answer for cast iron of this vintage (the bell geometry is too irregular for a Fernco shielded coupling). On younger cast iron with cleaner bells, we'd use a Fernco. Both are code-compliant; the choice is condition-dependent.

Related: RKT-MTH-02, RKT-MOR-B, RKT-MOR-D, all neighborhoods.