Croton Water Treatment Plant

The Croton Water Treatment Plant is the largest public infrastructure contract ever undertaken in New York City’s history. Sherwood was brought on to the project in 2011 by Grimshaw Architects and the Department of Environmental Protection (DEP) to replace the incumbent civil engineer at a time. This was a critical juncture in the project’s design development, as the DEP required significant value engineering while maintaining the goals, stringent security, and quality of the project. From a civil engineering and water management perspective, we were able to efficiently rethink the system function, materials, and quickly redesign and permit the project to maintain the goal of a net positive water management system that improved ecologically, experiential and function of the project while significantly reducing cost.

The project includes an advanced stormwater management design aimed at collecting site groundwater and stormwater flows for irrigation and other on-site re-uses. This unique design not only collects the water, but also treats it in a series of perimeter wetland cells, which help to enhance the project aesthetic while also creating a native wetland habitat.

Sherwood coordinated with the design team and local agencies to ensure the achievement of two key project goals: minimize discharge of site water into New York City’s combined sewer, and reduce potable water use through re-use of retained stormwater and groundwater. This work involved hydraulic and hydrologic design, close coordination with environmental and landscape architecture consultants with respect to wetland cell planning, and overall civil site design of parking and landscape areas.

Croton is the largest infrastructure project for the City of New York, processing a third of NYC’s drinking water. The building is nine acres wide, and sinks 12 stories into the earth. The golf course, which is the largest continuous living roof in North America, is the only visible part of the plant.