Zion Contracting served as the General Contractor for Project C30537, Critical Back-Flushing of Crosstown & Fulton Deepwells, in Brooklyn. This project was essential for maintaining the operational integrity of the Crosstown and Fulton Line dewatering systems by rehabilitating multiple deepwells, which are vital to preventing water accumulation and preserving infrastructure. The primary objective was to restore the dewatering systems to a state of optimal function, enhancing efficiency and reliability in critical transit infrastructure.

The scope of work involved comprehensive mechanical, electrical, and utilities tasks. In the mechanical scope, the team removed and replaced three 25 HP and two 40 HP submersible pumps, along with the removal and replacement of 14 exhaust fans, each equipped with a motor guard and gravity damper for efficient ventilation. Sump drains, pump drains, and vent bays were cleaned, snaked, and power-washed for maximum drainage performance. The project also required the removal and replacement of discharge pipes for all 14 deepwells, installing approximately 60 feet of stainless steel piping per well, with 1.5-inch ABS SCH. 40 perforated pipes as specified in drawings CDL-PL-2701 and CDL-PL-3000.

The electrical scope for the Fulton Deepwells (2702, 2703 & 2707) involved replacing existing flexible conduits, cables, and accessories, and providing new conduit, cables, boxes, and accessories to connect all eight Fulton deepwells to the VFD (Variable Frequency Drive) cabinet, as detailed in J&C drawings PTL-EI-603. For Crosstown Deepwells 2712 & 2713, existing flexible conduits and accessories for 40HP and 25HP submersible pumps were replaced from the terminal box (PTB) to the pump casing, including new conduit installations. Additionally, the work required the replacement of all conduits, cables, boxes, and accessories from panel boards and distribution boards to the exhaust fans, using new timer switches and thermostats to enhance operational control, as per I&C drawing CDL-EI-604.

The instrumentation and controls scope involved critical upgrades, including providing vent openings for all Variable Frequency Drive (VFD) panels located at Fulton Deepwells (DW#2701–DW#2708) and Crosstown Deepwells (DW2709–DW2714). The installation of AC axial exhaust fans with fan filter assemblies was designed to manage heat loads efficiently, based on calculated requirements to maintain ideal operating temperatures for VFDs. Additionally, transducers and cabling for each pump were replaced to ensure compatibility with new controls. Fourteen 1/3 HP sidewall propeller exhaust fans were installed with associated controls for enhanced airflow.

The utilities scope focused on Deepwell rehabilitation procedures as outlined in the contract. This included recording pump test results, scraping, cleaning, and painting Deepwell steel covers, removing and replacing corroded sections of each sump pit’s discharge pipes, and power-washing ventilators, drain pipes, and sumps to remove accumulated debris and optimize functionality. Zion Contracting’s coordinated approach to this project ensured that all critical elements were addressed, securing the operational resilience of both the Crosstown and Fulton Line dewatering systems.