Stormwater Management for Sustainable Communities
4160 Washington Road, STE 218, McMurray, PA 15317
email: email@example.com phone: (724) 288-7467
What We Do
Technical Analysis & Services International, Inc. (TASI) is a stormwater management technology company serving a wide range of industry customers through its expert services. TASI offers comprehensive consulting services and engineering support to be an integral part of the solution for our customer's stormwater issues. Our services can be used by the following: city public works, emergency response offices, water and sewer authorities, highway and rail transportation authorities and operation companies, hydro-power stations, nuclear power plant site selection teams, GPS map producers, TV stations, flood insurance companies, housing authorities, commercial and residential developers, house buyers and rainy season travelers.
Where We are
Located in Southwestern Pennsylvania, TASI has built relationships with some of the best minds in the engineering profession. The combination of experience and talent at TASI ensures quality, efficiency, constant creativity, ingenuity, and progress. Talents and ideas are utilized fully in a company of experts dedicated to excellence.
A Technical Service Company
TASI provides expert services to our clients at a competitive price. With the strength of its highly experienced engineering team, TASI has developed remarkable technical strength for handling the challenging and critical technical and engineering issues in stormwater management. Drawing on the extensive experience of our technical and engineering experts, TASI uses innovative analysis and design to provide high quality, cost-effective solutions to real-world problems. TASI believes that the world can be made better and safer, one project at a time.
Stormwater Management-Focusing on the study and solutions for issues related to stormwater, such as flash floods, wastewater, mud-slide, green infrastructures, etc.
Flash Flood Management-Focusing on the study and solutions for issues related to flash flood. It is one of the toughest issues in stormwater management.
Wet Weather Management-Focusing mainly related to wastewater issues in wet weather. Flash floods are the main reason that causes the stormwater issues. See www.epa.gov for details.
Technical Challenge of Flash Flooding
Flash floods are the root cause of most stormwater management issues internationally.
Flash floods are the most damaging natural disaster in the United States. In 2015, they accounted for 24.7% of weather-related deaths and 43% of property damage. They create severe environmental pollutions, health risks and contribute to economic decline, particularly for economically strained communities.
Flash floods are caused by heavy rainfall (1 to 12 inches) in short time durations (1 to 6 hours) produced by warm season thunderstorms. Several other factors contribute to the flash flood potential. Rainfall history during the days leading up to a flash flood event can result in saturated soil and high stream levels before the onset of the flash flood producing rainfall. The wet soil condition results in greater runoff into the streams, causing a much more rapid rise in stream levels and more severe flash flooding. Another factor is steep topography, as steeper valley walls produce a more rapid overland flow of rain water into the stream. A major factory leading to increases both in the frequency and potential severity of flash flood is urbanization. Impervious ground surfaces such as parking lots and roads, drainage from roofs of homes and buildings, along with storm drainage and sewer systems of limited capacity all contribute to the increased flash flood threat in urban areas. As urbanization continues to increase, the flash flood threat in the urban environment increase as well.
Currently, flash flooding is only addressed by the National Weather Service’s flash flood warning program. The EPA has established a consent decree. Water authorities nationwide implement wet weather management projects to eliminate storm sewer overflow, the direct consequence of flash flooding. These rate-supported capital projects deal with the consequences of flash floods but still need to accurately take into account flash flooding itself.
Engineering design for storm drain networks are often based on “return periods” of rainfall produced by the National Weather Service. These climatic estimates of rainfall return period are all based on rain gage data. The heaviest rainfall amounts produced by thunderstorms are seldom captured in the rain gage network. The engineering design using the rain gage return periods will generally greatly underestimate both the frequency and amount of the heavy rainfall. If only rain gages were usedto detect flash floods only about 5% of all flash floods would be detected. Using the rainfall from the WSR-88D, the NWS in Pittsburgh detects over 90% of all flash floods. TASI’s FFM programuses WSR-88D data to replay all flash flood events. FFM can also produce the “rainfall history” of rainfall in a specific flash flood watershed for the week prior to the flash flooding. FFM canalso created rainfall in 5 minute time steps through the entire duration of the flash flood producing rainfall. FFM can also show results of historic flash flood events, to show the true spatialand temporal distribution of rainfall that caused the flash flood events. These events include the Johnstown flash flood of 1977, the Etna, PA flash flood of 1986, and the Shadyside, OH flashflood of 1990.
With the advanced and realistic estimates of the spatial and temporal distributions of heavy rainfalls and the rainfall history, TASI will help both the aggressive engineering solutions and green infrastructures to effectively resolve or mitigate the persistent storm sewer overflow, especially the combined sewer overflow (CSO).
TASI provides integrated solutions and analysis for stormwater management design, analysis and product development of highly complex engineering issues in the following areas:
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Last Updated: March 1, 2017