Wooden water tanks were once ubiquitous on the urban skyline—cylinders standing guard like sentries above the rooftops. Today, however, it seems that water containment devices are increasingly tucked away behind walls and integrated into building design.
Most contemporary buildings pump water to large reservoirs in the top floors to make use of gravity flow. According to construction industry experts, a current building trend is the incorporation of a number of smaller storage vessels to enhance a building’s energy efficiency.
“Newer towers tend to hide their reservoirs inside and often use multiple tanks housed throughout the building so water can be pumped to the top in smaller increments,” a recent New York Times article explains. The article asserts that the new One World Trade Center has 16 water tanks and indicates that when the city’s tallest residential tower, 217 West 57th, opens in the coming months, 11 different stainless-steel tanks will hold water for the building’s inhabitants.
Gravity is crucial for water systems in New York City. There, reservoirs north of the city are located at a higher elevation—an altitude difference equivalent to a six-story building. Therefore, the pressure provided by the elevation change and gravity ensures that water travels to the sixth floor of most buildings. Beyond that height, building designers and operations managers must enlist pumps.
In some cases, water storage systems can be used to enhance a building’s design. In San Francisco, One Rincon Hill—at one point considered the tallest residential building west of the Mississippi River—uses a concealed water tank as an engineering device. A 50,000-gallon reservoir placed at the top of the structure has a stabilizing effect, preventing the tower from swaying in the wind using a technique called tuned liquid dampening.
The development of zero net buildings that consider energy and water conservation are also an emerging trend in building design, according to experts in the field. In a recent Building Design + Construction article, author Prem Sundharam outlines the increasing integration of water resource management into building design, highlighting the concept of “buildings as a resource.” Building structures can serve as water conservation tools used to help address issues at the water-energy nexus.
“For decades we have considered buildings as a user and consumer of resources. We have measured our success by how much we can limit that consumption. But if we flip that idea on its head and consider how we can reuse our water to nourish the environment, or how much and in what condition we return the water to the system, our buildings then become a resource provider rather than a consumer.”
