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Article 4 · Technical Due Diligence

Subsurface Due Diligence — The Hidden Underground Infrastructure Checklist

The most critical physical assets in a community — and the greatest capital risks — sit underground.

1. Water Delivery Infrastructure

  • City water vs. private wells: municipal water is preferred because testing, filtration, and pressure regulation are managed by the municipality. Wells require state testing, pressure tanks, softeners, and backup generators.
  • PVC / PEX / HDPE: modern, durable, chemically inert, 50+ year service life.
  • Galvanized steel: common in 1960s/70s parks; rust, scaling, reduced flow, and sudden pinhole leaks. Budget a full repipe if present.
  • Polybutylene: common in 1980s construction; notorious for micro-fractures and widespread bursts.

2. Wastewater & Sewer Networks

  • Municipal sewer connection: the lowest-risk profile — the park simply delivers to the city main.
  • Private septic: verify tank pumping logs, soil percolation capacity, and reserve land for a replacement leach field.
  • Wastewater lagoons: check berm integrity, aerator functionality, and active state DEP discharge permits.
  • The mandatory sewer video scope: never close without a licensed commercial plumber camera-scoping all main trunk lines for root intrusion, bellies, cracked clay tile, or collapsed Orangeburg.

Key Takeaway

Never close on a park based on surface appearances alone; comprehensive diligence requires video scoping sewer lines, testing water pressure, and auditing electrical capacity.

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