Water Condition Survey and Inspection of Structural Components – W 4th St & 8th Ave Subway Station

This Metropolitan Transportation Authority’s (MTA) Construction & Development (C&D) task order (Planning No. MW57-6921) provided for inspection of the upper 8th Avenue Line level, lower 6th Avenue Line level, intermediate mezzanine and back of house areas, and stairs and fare control areas of the West 4th Street and Washington Square stations.

The project included surveying water conditions and water infiltration throughout the station, including, but not limited to, street level, platforms, mezzanines, stairs and corridors, non-public rooms and areas, employee facility areas, station rooms, utility, mechanical, electrical, communication, and signal rooms, above-ceilings, closets, and abandoned areas. The surveys were to visually determine and document all probable leak sources and evaluate deteriorated structural members due to water infiltration.

Garg Consulting Services, Inc. (Garg) provided structural engineering and inspection services. Tasks included, but were not limited to:

• Thorough visual inspection of common water access points, including the interior of street-level ventilators and shafts, and application of water dye tracers into drainage troughs. Tracing of active leakage on follow-up visits and after significant rain events.
• Visual and hands-on (as needed) structural evaluation of deteriorated structural members
• Assessment regarding the condition of all inspected structural elements and recommendations concerning structural findings, both significant and typical.
• Development of short-term recommendations for immediate and intermediate solutions and long-term recommendations for repair and rehabilitation solutions to eliminate current sources and paths of water infiltration.
• Compilation of inspection report and record files including updated station drawings, inspection records, testing procedures and results, videos, and CADD sheets.