Gate Repair of the Stamford Hurricane Barrier located in Stamford, Connecticut

SPECIAL NOTICE Description: The U.S. Army Corps of Engineers, New England District (CENAE) is issuing this Special Notice Announcement for the Gate Repair of the Stamford Hurricane Barrier located in Stamford, Connecticut. The purpose of this announcement is to solicit input from industry as to the construction means and methods as well as anticipated construction durations for the proposed work. CENAE plans to award this project using an invitation to bid design-bid-build approach. CENAE anticipates issuing the Solicitation on or about December 2023, with award anticipated by February 2024. The Period of Performance is expected to be 545 days. The downtime of the gate will need to be minimized; therefore, a time of year restriction is under consideration. For the purposes of this special notice, assume that the gate will only be offline March - June of 2025. If the Contractor can lock the gate in the upright position, then remaining work may be completed outside of this window. The NAICS code for the work described below is 238120 / 237990. The Solicitation is not available at this time. This special notice does not constitute a commitment by the Government. Project History: Following hurricane “Carol” in August 1954, Congress authorized a study (Public Law 71, 84th Congress, 1st session) to determine the feasibility of a protective barrier in the Stamford area. A project was determined to be structurally feasible and economically sound, and subsequently authorized for construction for the Flood Control Act, approved 14 July 1960 (Public Law86-645, 86th Congress). Construction of this project started in May 1965 and ended in January 1969. The Stamford Hurricane Barrier is located on the north shore of Long Island Sound, situated in Stamford Harbor in the City of Stamford, Connecticut. The Stamford project is divided into three principal features: West Branch barrier, which protects the area between the west and east branches East Branch barrier which connects to the West Branch barrier and extends across the mouth of the East Branch, and Westcott Cove barrier which protects the residential area of Rippowam Street and skirts Westcott Cove in Cummings Park. The barrier is operated to protect approximately 600 acres of commercial property including some of the principal manufacturing plants and business offices of the City against flooding resulting from storm tides. The federally maintained portion of the project extends easterly from the chain link fence at the terminus of the west Branch dike across the mouth of the East Branch navigation channel and terminates at the eastern limit of the East Branch Dike. It includes a 1V:2H sloped rock-faced earth dike, a 90-foot navigation gate, and the East Branch pumping station which is located at the navigation gate structure. The remaining portions of the project are owned by the City of Stamford. Features of the federally maintained portion of the project that are regularly inspected include: the East Branch Dike; the navigation opening including the pump station, sump and sluice gates; the hydrologic and meteorological monitoring instrumentation; the navigation gate and the east and west abutments to the opening. The pumping station contains two 30-inch vertical propeller type pumps with a total capacity of 100cfs. An 8’ x 8’ sluice gate is provided to drain the harbor and reduce pressure on the navigation gate in the event that the navigation gate becomes inoperable in a closed position or is maintained in the closed position during an outgoing tide. Project Requirements: Repair/Replacement: Replace the west side crane rails and supports. Replace the hydraulic fluid from the hydraulic power system. Replace the hydraulic hoses, desiccant breathers, filters, sensors and gauges. Replace electronics that are part of the hydraulic power system that are obsolete and are no longer supported by the manufacturer. Replace the PLC control system, update the relay control system. Disassemble the barrier gate lifting link to lifting ear connection. Evaluate the condition of the bushing, pin, fasteners, lubrication channels and fittings and washers. Replace components as necessary. Reinstall along with installing the missing washer and correctly installing the keeper plates. Replace bushings in hydraulic cylinder rod ends. Rehabilitate the gate hinge assemblies (Likely pin is fractured at Hinge #4). Rehabilitate the trench cover plates. To further depict the required work, DRAFT plans from the Design-Bid-Build Construction Documents are included with this Special Notice. Items shown on these figures will be revised during the current design effort to reflect recently imposed changes and the industry feedback of this Special Notice. Questions for Industry: Discuss your approach and the anticipated equipment you intend to mobilize to the Stamford Hurricane Barrier for gate removal and installation? Do you intend to do the rehabilitation work to the gate onsite or will the gate be brought to an offsite location to complete the rehab work? If the gate is offsite for some of the rehab works how long do you anticipate it being offsite? What is the shortest timeframe to have the gate offline? Is it possible to complete the work on the gate and then reinstall and lock in the upright position while remaining work is completed? If required, how long to remobilize in the event of a storm surge? How much notice would you need to reinstall and how would you complete this? Based on the attached bid schedule, please provide durations you would likely require conducting each element of the work, and if you are bringing the gate offsite where that element of the work would be completed? Identify components of the work would constitute long lead items for procurement and fabrication. Long lead items are items that require more than 3 months to procure or fabricate. Please provide an approximate timeline associated with each long lead item. Do you self-perform diving operations work or use a subcontractor? Based on the attached record drawings do you anticipate being able to fully inspect the hinge shoe assembly and install new “ampco” press fit material in the shoe with diving operations? Are “Ampco” press fits and bushings considered to be long lead time items? These are referenced to as alloy metals on the new drawings but are referenced throughout the information drawings as “Ampco”. Does the jig assembly as shown in S-504 appear to be a viable solution to remove and reinstall bushings as currently configured? Based on the record drawing and inspection reports, and assuming the hinge shoes are damaged and need to be replaced, please discuss your approach to removal and replacement and specifically speak to whether you anticipate doing that work with diving operations? See attached sheet “STA-1_SHT-120_Special-Notice”. Do you believe the shoes can be removed if the fasteners are not able to be removed the way they were designed? Does the jig assembly as shown in S-504 appear to be a viable solution to remove and reinstall bushings as currently configured? Please provide any questions or comments you might have. Please contact Contract Specialist, Elizabeth Glasgow at [email protected] for links to Specs and Drawings and Bid Schedule Due Date: Responses are due by 14 August 2023 via email to Elizabeth Glasgow to [email protected].