Columbia University Dock Replacement

The Muscota Marsh East Dock on the Spuyten Duyvil Creek portion of the Harlem River in Manhattan is adjacent to Columbia University’s Baker Athletic Complex. It provides water access for the University’s rowing teams and the community’s rowing clubs.

Challenge

The timber floating structure reached the end of its service life as deterioration of the system compromised its performance and sediment accretion limited its use to periods of mid to high tide. Considering minimum water depths required to provide under clearances at low tide and the proximity of the navigation channel in the river, a new alignment and float configuration were developed to improve user safety and ease of boat launch.
 

Solution

The performance requirements for the new float were developed through collaboration with Columbia University’s Athletic Department, its rowing staff, and with forethought for the program’s current and anticipated boats and shells; launch a and haul out procedures; and rowing classes. With this understanding, GZA prepared a schematic design for replacement of the floating docks and anchor piles. The design considered conditions such as tidal water levels; wind, snow, ice, and wave loadings; dead and live loading of the docks; mooring and berthing loads on the floats; and additional loadings. Comments from the University were incorporated into GZA’s draft design plans and technical specifications. After approval, GZA prepared final bid documents. 

Additionally, GZA prepared a Fish Habitat Assessment, Subsurface Soil Investigation, Permitting Assistance and Construction Support Services. Required permit applications and documentation included US Army Corps of Engineers Section 404/10 Permit, NY State DEC Tidal Wetlands/Excavation & Fill in Navigable Water/Docks, Moorings or Platforms permits; NY State Office of Parks, Recreation and Historic Preservation (OPRHP) Project Review, National Marine Fisheries Service (NMFS) letter and project documents; NY Department of City Planning, Local Waterfront Revitalization Program Consistency Review application and supporting information, NY City Department of Small Businesses Permit; New York City Department of Parks and Recreation Construction Permit with contractor insurance and bonding information.
 

Benefit

The new floating dock met the University’s objectives for this project. It is structurally safer, extends farther out to address changing water levels, and has improved access to the water to launch boats easier.