Connecticut Water Treatment Facility


Located on the suburban outskirts of New Haven, the facility is a reserve water source for the South Central Connecticut Regional Water Authority. It draws water from nearby Lake Whitney, at the base of the Mill River Watershed. The site is adjacent to the Eli Whitney Museum, which commemorates the famous inventor and his son, who first dammed the adjacent Mill River for use as a water supply in 1806.

Frugal Elegance

The use of the most elemental of landscape architectural tools—soil, water, and plants—offsets the sleek form of the facility building. The design creates topographical variety and interest through sustainable reuse of excavated soil. Swales replace a traditional engineered drainage system. The planting program, inspired by restoration ecology, is at once primal and sophisticated in its extent and complexity.

Ecological Integrity

The new topography is stabilized using bioengineering methods. Site stormwater and runoff from the building’s green roof are filtered as they move through the landscape. The planting scheme uses native species that require no fertilizers or pesticides, reducing the facility’s impact downstream. The plant palette is also calibrated for seasonal variation in color and texture, and anticipates the natural evolution of plant communities over time.

A Watershed in Microcosm

The landscape is designed to be a didactic microcosm of the entire regional watershed. The swales guide site runoff through a series of discrete landscapes—including farmland, meadow, and valley strea—before collecting it in a new pond that recharges the groundwater table. Meandering footpaths allow visitors to move through this narrative and consider how water interacts with the land.

Community Use

While the utility is privately owned, the landscape architecture and building work to engage, rather than ignore, the adjacent residential neighborhood. The site also hosts the historic Eli Whitney Barn, a space for community events and programming. By transforming a formerly flat lawn into a dynamic, ecologically diverse public space, the design improves long-standing community use of the grounds and integrates the site with its suburban surroundings.


Project Type


New Haven, Connecticut, United States

Related links


  • Steven Holl Architects
  • Michael Van Valkenburgh Associates, Inc.