Stormwater system for the Brooklyn community, New York

Detailed starting situation

STF Filters was asked to design and develop a comprehensive system to treat rainwater in order to reduce water consumption at a New York City Health Department facility by reusing rainwater.

This need of the New York sanitation department arose from a plan to implement actions with a positive impact on the environment, with the aim of reducing the water consumption of its facilities and therefore reducing the city's water consumption.

STF Filters provided a comprehensive solution consisting of two skid platforms linked together. This solution allows rainwater to be filtered and disinfected and, once treated and when required, to be re-injected back into the water network of the building where it is installed, with the aim of recharging toilet cisterns and other auxiliary services in the buildings.

The challenges

The main challenge of this project was to design a solution that would integrate all the necessary elements to be able to properly treat rainwater, allowing it to be re-injected back into the mains water.

During the design of the solution, another important challenge arose, related to the transport of the equipment. It was necessary to design a modular and separable unit that, due to all the elements it incorporated, was of large dimensions, in order to adapt it to the means of transport available and to the final location of the system.

Solution provided

STF Filters' engineering team designed and developed a comprehensive solution consisting of two skid platforms, through which rainwater is treated for reuse. The health department's facilities already included a tank to store rainwater. STF Filters' solution consists of two skid platforms connected to each other. The first platform houses a pair of pumps to capture water from the rainwater tank. On this platform, the water is treated with the FMA-7000-UV automatic mesh filter, a two-stage filter that first filters the water using its mesh filtration cartridge and then disinfects the water using ultraviolet rays. On the second platform, the rainwater is treated in two activated carbon filters that remove impurities, such as pesticides, from the water that the filtration cartridge could not retain.

This second platform also houses a tank to collect drainage water from the filter elements. After this process, the water is injected to refill toilet cisterns and other auxiliary services.

This comprehensive solution consists of a series of valves that allow the entire system to be connected and disconnected depending on the availability of rainwater at any given time. This series of valves also allows water to be recirculated back to the tank, thus providing for any type of situation.

Results

This system allows to manage a water flow of 22.70 m³/h, which implies a total saving of mains water, using instead treated rainwater for the use of cisterns and other auxiliary systems. This saving will depend mainly on 2 factors:

• The rainwater available in the tank, a value subject to atmospheric conditions.
• The size of the rainwater tank available at the facility, which will vary from facility to facility.

These sanitation department facilities are Green Building certified. This is possible thanks to the incorporation of this type of system, among others.