Macombs Dam Historic Swing Bridge Seismic Retrofit Value Engineering Study, Bronx, NY—City of New York, Office of Management & Budget (OMB) Project Background

Macombs Dam Historic Swing Bridge Seismic Retrofit Value Engineering Study, Bronx, NY—City of New York, Office of Management & Budget (OMB) Project Background. Opened to traffic in 1895 and designated a New York City landmark in 1992, The Macombs Dam Bridge is a through-truss swing bridge that spans the Harlem River linking the boroughs of the Bronx and Manhattan. It is the major vehicular route from Manhattan to the new Yankee Stadium, opened in 2009. In addition to crossing the Harlem River, the Macombs Dam Bridge crosses the Major Deegan Expressway, Metro North and CSX railroad tracks, and the parking lot for the Bronx Terminal Market. The 2,540-foot bridge features 78 spans of various types including a 1,362-foot long steel viaduct over West 155th Street; a 415-foot long center swing span with 150 feet of horizontal clearance through the two navigable channels and 28 feet of vertical clearance in the closed position; a 220-foot camelback truss; and several ramps and approaches. A two-stage electric engine powers the swing span. The substructure consists of steel column bents, concrete columns, and masonry piers. The center span rests on a center pier and can swing open to permit boat traffic through one of the two navigable channels. The foundation of the Manhattan pier was sunk on a pneumatic caisson to rock, as was the foundation of the center pier. The Bronx pier was built on rock also, but in an open sheet-pile dam, and from that point across the swamp to 161st Street the plans called for pile foundations. However, the unstable swamp on the eastern bank required surrounding on Bronx pier in with a collar of sand and concrete.

The first bridge on the site was built in 1814 by Alexander Macomb. It was a dam and bridge that connected his tide-powered grist mill on the western bank of the Harlem River to his land on the east bank. The second bridge was constructed in 1861 to accommodate traffic along the river. The iron-and- wood bridge featured a 210-foot turntable draw span with two 60-foot openings constructed on a masonry main pier and a roadway and sidewalks constructed of wooden planks. It underwent a major reconstruction in the 1870s, but became dangerous again by the early 1880s, requiring replacement. Designed by Alfred P. Boller, the 1895 construction used steam power to propel the draw mechanisms, and gas lighting provided illumination for the roadway. In 1904, steam and gas power sources were replaced with electrical sources. In the 1990s, a large-scale rehabilitation was completed in which the substructure, superstructure, swing span machinery, and control system were addressed.

Project Objective. The scope of this seismic retrofit project includes upgrades to the west approach span, swing span, deck truss span, camelback truss span, and one Bronx exit ramp. It is intended to maintain the bridge's functionality after an earthquake by increasing structural flexibility. The 155th Street Viaduct rehabilitation will include replacements of the floor beams, ends of girders, columns, column bracing, and anchor bolts. The current scope of work also calls for a new extension to the northeast portion of the timber cribbing fender to correct an existing misalignment. Scheduled for a two-year completion in 2016, total project costs are estimated to be $74,074,231. VE Workshop Goals and Approach. The client identified goals for the workshop conducted in 2009 including reviewing the effectiveness of the proposed design solutions, and developing cost-effective engineering and constructability alternatives to help improve the value of the project for the City from a functional as well as cost-benefit perspective. The VE study focused on the preliminary plans, 60% submission plans, and various studies and reports provided by the DOT and their design consultant, Parsons Brinckerhoff Quade and Douglas.

Advantage Facilitation Services used the value methodology and VE Job Plan defined by SAVE International to facilitate the workshop. VE team members were encouraged to explore a wide range of ideas and to develop implementable recommendations. RH & Associates assisted in facilitation. Bremmer Consulting LLC provided administrative and report preparation services for the study.

Results Creativity. The VE team developed19 VE alternatives, including six design suggestions. Performance Criteria. VE ideas considered the products, methods, and materials included in the design, and the effects of the project schedule, with particular emphasis on the time required for lane closures and the disruption to traffic in the project vicinity. Maintenance and protection of traffic, especially during the months of April through October, are major concerns in light of the close proximity of the bridge to Yankee Stadium. Considerations included the overall improvement potential and/or cost savings relative to the cost of design changes. Highlighted Alternatives

Recommendation Initial Cost Savings Life Cycle Cost Savings

Model Column Bases as Pin Connections to See if Possible to $900,000 N/A Eliminate All Anchor Bolt Replacements

Isolate the Entire 155th Street Viaduct and Link it Together $2,500,000 N/A

Modify the Designated Critical Route $1,800,000 N/A

Client Reference Prime Consultant Reference Jill Woller, Ginger Adams CPF CVS-Life FSAVE Director, Technical Services Principal City of New York, Office of the Mayor, Office of Advantage Facilitation Services Management and Budget 6309 Charmichael Street, Fort Collins, CO 80528- 75 Park Place, 8th Floor, New York, NY 10007 7071 (212) 788-6137 (970) 223-0703 [email protected] [email protected]