This collection of photographs of the water towers of New York City are not only a tribute to these iconic structures of the city’s landscape, but also a pretext to explore hidden details of its architecture. Rooftop water towers are an unique opportunity to experiment with shapes, forms and textures, a frequent component of my photographic quest. Inspired by famous paintings like Edward Hopper’s “Rooftop” (1926), and by the ever changing architectural scene, I focused my attention on the cylindrical wooded structures and framed them with the surrounding buildings. This a is a collection of many years of walking the streets of New York with my camera.Water is our most precious natural resource. New York City’s skyline is dotted with wooden water towers, the result of a 19th century’s law requiring all buildings taller than six stories to be equipped with a rooftop water tank. This was necessary to prevent the need for excessively high pressures at lower elevations, which could burst pipes. Pressure in the city’s pipes can take water up only about half a dozen stories, so a higher building needs either a pumping system or a system of tanks. A water tower seemed like the better solution, since it also provides emergency storage for fire protection. A water tower store 25,000 to 50,000 liters of water until it is needed in the building below. The upper portion of water is skimmed off the top for everyday use while the water in the bottom of the tower is held in reserve to fight fire. When the water drops below a certain level, a pressure switch, level switch or float valve activate a pump or open a public water line to refill the water tower. Even today, no sealant is used to hold the water in. The wooden walls are held together with cables but leak through the gaps when first filled. As the water saturates, the wood swells, the gaps close and the tank become impermeable.

The first comprehensive steel tanks book published in more than a decade Developed by members of the American Water Works Association (AWWA) General Steel Tank Committee, Steel Water Storage Tanks: Design, Construction, Maintenance, and Repair is the most authoritative source of industry information available. This in-depth reference describes the use of steel tanks for potable water storage and includes details on tank sizes, capabilities, styles, construction, appurtenances, site selection, design, operation, maintenance, rehabilitation, inspection, and security. Complete coverage of: Tank history, typical configurations, locating, sizing, and selecting Selecting and specifying appurtenances Controlling corrosion Contractual considerations Foundations Construction of welded-steel water-storage tanks Construction of bolted-steel water-storage tanks Operation Inspecting new-tank construction Maintenance, inspection, and repair Potable water security Tank rehabilitation

Legionnaires' disease, a pneumonia caused by the Legionella bacterium, is the leading cause of reported waterborne disease outbreaks in the United States. Legionella occur naturally in water from many different environmental sources, but grow rapidly in the warm, stagnant conditions that can be found in engineered water systems such as cooling towers, building plumbing, and hot tubs. Humans are primarily exposed to Legionella through inhalation of contaminated aerosols into the respiratory system. Legionnaires' disease can be fatal, with between 3 and 33 percent of Legionella infections leading to death, and studies show the incidence of Legionnaires' disease in the United States increased five-fold from 2000 to 2017. Management of Legionella in Water Systems reviews the state of science on Legionella contamination of water systems, specifically the ecology and diagnosis. This report explores the process of transmission via water systems, quantification, prevention and control, and policy and training issues that affect the incidence of Legionnaires' disease. It also analyzes existing knowledge gaps and recommends research priorities moving forward.