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Lunch and Learn: Infrastructure at DDC

DDC is proud to offer the STEAM Virtual Lunch and Learn Series to high school students throughout New York City. Lunch and Learn is a one hour interactive presentation by DDC professionals speaking about their current role, career path and education. The series connects DDC professionals in the built environment, administration, construction management and design to students to share their experience and knowledge.

On July 16, 2020, in the 3rd session of the series, Deputy Commissioner Eric Macfarlane presented on infrastructure, specifically, “Slip Line Installation: For the Structural Rehabilitation of the New York City’s Trunk Water Main System.”

Deputy Commissioner Macfarlane focused on the infrastructure of Astoria, Queens, one of the world’s busiest and most diverse communities in New York City and outlined the challenges faced by the continual maintenance upkeep of the city’s 6,800-mile water distribution system. This includes trunk water mains, which distribute 1.2 billion gallons daily from the three massive water tunnels to nine million NYC residents, which necessitates implementing non-conventional engineering to minimize disturbances to communities, businesses and traffic. The rehabilitation of an 8,500-linear foot stretch of decommissioned 60-inch diameter trunk main spanning seventeen city blocks in a highly dense, commercial and residential hub, centrally located in Astoria, Queens is a tremendous undertaking. To recommission the trunk main while minimizing environmental, social and economic impacts, design engineers from DDC devised an innovative design solution by electing to slip line the existing 60-inch diameter steel water main with a 52-inch diameter steel water main. Given the existing 60-inch main’s deteriorated state, any lining methods used must incorporate full structural rehabilitation.

A poll taken during Deputy Commissioner Macfarlane’s presentation showed that many students were interested in becoming architects, engineers and even a chemist. He emphasized the importance of having a career objective.

“The work of the Infrastructure division is critically important to the construction and upkeep of NYC’s 6,500 miles of water mains citywide. Their work makes it possible for NYC to deliver the world renowned NYC tap water that New York is known for and NYC residents rely on every day of the year,” stated Deputy Commissioner for Community Partnerships and STEAM Initiatives, Lee Llambelis.

New York’s City Tunnel No. 3 is one of the most complex and intricate engineering projects in the world. The tunnel will eventually span 60 miles. The size and length of the tunnel, its sophisticated control system, the placement of its valves in special chambers and the depth of excavation, represent state-of-the-art technology. While city tunnel no. 3 will not replace city tunnels no. 1 and no. 2, it will enhance and improve the adequacy and dependability of the water supply system and improve service and pressure to outlying areas of the city. It will also allow for the shutting down, inspection and repair of city tunnels nos. 1 and 2 for the first time since they were activated in 1917 and 1936, respectively.

There were many factors to consider during this project including environmental, financial and community considerations. Pollutants, financial impact on local business and noise and traffic considerations for residences and businesses were all important factors. DDC strategically located all tools and rehabilitation trunk materials to mitigate disruption to services and quality of life. The project conclusion exceed expectations. From start to finish, the water main project was completed in ten months - seven months ahead of schedule. The rehabilitation work was also completed under budget and the slip lining reduced open-cut trenching by at least 80%.

A sculpture of Frederick Douglass

A sculpture of Frederick Douglass by artist Gabriel Koran

Deputy Commissioner Macfarlane also spoke about DDC’s work on plazas around the city and specifically the Frederick Douglass Circle as an example of plaza work enhanced by DDC’s Percent for Art Program. The reconstruction of Frederick Douglass Circle, on the northwest corner of Central Park, revitalized the traffic circle with new landscaping, lighting, and traffic signals. In addition, the project features a new sculpture of Frederick Douglass by artist Gabriel Koran, and a fountain wall designed by Algernon Miller, featuring the constellations, which could have served to guide northbound slaves toward freedom. Deputy Commissioner Macfarlane further noted, “Design can create equitable spaces, such as Frederick Douglas Memorial that convey a sense of welcome to all.”

Deputy Commissioner Macfarlane shared the impact COVID-19 has had on DDC projects. He noted that in general projects were completed faster because of the shutdown, and low vehicle and pedestrian traffic enabled on-going construction projects continued without interruption.

Eric C. Macfarlane leads the New York City Department of Design and Construction’s Infrastructure Division with a technical staff of 500 employees, consisting mostly of engineers, project managers, and analysts. The division is responsible for the design and construction management of the capital infrastructure programs for the City of New York consisting of: consolidated roadways, sanitary sewers, storm drainage system, water distribution network and various urban landscape improvements. Currently the division has a 5 years capital plan portfolio of 625 projects in various, phases, from planning, design and construction, valued at more than $10 billion.

About the NYC Department of Design and Construction

The Department of Design and Construction is the City’s primary capital construction project manager. In supporting Mayor de Blasio’s long-term vision of growth, sustainability, resiliency, equity and healthy living, DDC provides communities with new or renovated public buildings such as such as firehouses, libraries, police precincts, and new or upgraded roads, sewers and water mains in all five boroughs. To manage this $14 billion portfolio, DDC partners with other City agencies, architects and consultants, whose experience bring efficient, innovative and environmentally-conscious design and construction strategies to City projects. For more information, please visit