WSSC_Special_Trench_Restoration_Detail.pdf

This is a technical specification detail document for the Washington Suburban Sanitary Commission (WSSC) related to special trench restoration requirements for paved areas during pipeline construction projects. The document provides standardized construction details for trench backfill, pipe installation, and pavement restoration procedures. It references WSSC Standard Details for various pipe types including rigid pipe gravity RCP sewers (M/8.0), flexible pipes such as ductile iron and PVC pipes of varying sizes (M/8.1a, M/8.1b, M/8.1c), and specifies compliance with WSSC Specification Section 02315 for earthwork, backfill material, compaction, and compaction test requirements. The detail establishes jurisdictional pavement restoration standards based on location, requiring adherence to Prince George's County Standard Detail STD 300.18, Montgomery County Standard Detail MC-801.02, State Highway Administration Standard Detail MD 578.01, or WSSC Standard Detail M/5.2 where no jurisdictional requirements apply.

The specification detail illustrates the vertical profile of a restored trench in paved areas, showing the progression from undisturbed earth through backfill, pipe installation per WSSC standards, and final pavement restoration including hot mix asphalt base and bituminous concrete surface course. The document establishes that final mill and overlay work is to be completed by others, and pavement restoration must follow the applicable jurisdictional requirements based on the project location. This technical standard is directly applicable to the Beaufort Place Water Main Replacement project in Montgomery County, Maryland, which requires installation of new ductile iron water mains and restoration of approximately 13,305.6 linear feet of roadway across multiple streets.