It is a relatively simple concept that results in a controlled flow system of rainwater from the roof.
Nyc roof water detention.
But a well engineered solution is essential.
As stormwater flows it sweeps up pollutants such as oils chemicals sediments pathogens and trash.
The department of buildings and the department of health.
Rooftop detention also known as a blue roof is designed to provide temporary storage and slow release of stormwater runoff.
These systems store and slowly release storm water to the sewer system detention or dispose of stormwater onsite retention through infiltra tion to soils below evapotranspiration and re cycling onsite.
Rooftop detention systems or blue roofs temporarily store and gradually drain rainwater off a building s rooftop in order to slow the flow of stormwater into the city s sewer system when it rains.
These systems have an open bottom and can incorporate perforated pipe and stormwater chambers for added detention volume.
This technique is most commonly used in dense urban areas where other methods of stormwater detention are impractical.
Minimum and or per construction code away from building foundation.
1106 6 size of roof gutters the size of semicircular gutters shall be based on the maximum projected roof area in accordance with table 1106 6.
Rooftop systems are used to control runoff of stormwater and rooftop detention is the heart of blue roof technology.
Parapet wall roof drainage scupper and overflow scupper location shall comply with the requirements of the new york city building code.
Hazen and sawyer recently designed a combination green and blue roof system for a building in new york city.
Systems are primarily designed with a gravel bed that stores water until it can infiltrate into the ground.
Rather than being absorbed naturally into the ground much of new york city s stormwater eventually flows into storm drains or catch basins and from there into the sewer system.
Subsurface detention systems with infiltration capability provide temporary storage of stormwater runoff underground.
Philip kraus ceo and owner of manhattan based fred smith plumbing heating notes that monitoring of rooftop water tanks falls under the purview of two agencies.
Water performance standard including subsur face rooftop and stormwater recycling systems.
Provides equivalent stormwater detention to a green roof at a fraction of the cost.
The regulation of the cleaning and inspection of water tanks is provided by two separate new york city agencies.
Above the ground water table to prevent possible ground water infiltration into the sewer system and 10 ft.