Client: Urbahn

Owner: Metropolitan Transportation Authority (MTA); New York City Transit Authority (NYCTA)

Services Provided: Cost Management, Cost Estimating

Tunnel Structure Repairs Program 7th Ave & 8th Ave Lines

New York, NY

Ellana provided cost estimating services for design services of stormwater mitigation at the 7th & 8th Avenue Line, between the 79th street and 86th street stops in Upper Manhattan. Drainage on the 7th Avenue line relies on gravity-fed drainage to remove water, and the drains connect to the NYC sewer system near West 81 St. Water in the subway tunnels cannot enter the sewer system because there is a surcharge at the point where the drainage pipes for the subway link to the sewer. To stop wastewater from entering the tunnels, a backflow preventer is installed between the sewer and the drainage pipes of the subway. This project modifies/upgrades the current water pumping system by working to ensure that water can drain from the right of way during heavy rainfall. A new connection to the nearby city sewer system is also required.