Join EPA for a Watershed Academy Webcast on Oct. 2, 2013 from 1:00 pm to 2:30 pm Eastern on the new “National Stormwater Calculator.” (See Post Below) This new calculator is designed for anyone interested in reducing runoff from a property including: site developers, landscape architects, urban planners, homeowners and others. It can help users decide which stormwater management practices to install such as a rain garden or a green roof. This calculator is a desktop application that estimates the annual amount of rainwater and frequency of runoff from a specific site anywhere in the United States (including Puerto Rico). Estimates are based on local soil conditions, land cover, and historic rainfall records.
You can download the Stormwater Calculator at www.epa.gov/nrmrl/wswrd/wq/models/swc/.
Register for the Webcast at www.epa.gov/watershedwebcasts
Effective August 20, 2013, on motion of Director Erlbaum, seconded by Vice-Chair Moulton, it was unanimously adopted that the time frame for a complete response to a District inadequate review letter, for non-permitted project applications, be 60 calendar days from the date of the inadequate review letter. The application will be considered withdrawn when the 60 calendar day timeframe has passed without a complete response to the listed deficiencies put forth in the inadequate review letter. At that time a new submission will be required, inclusive of all applicable fees.
As part of its continuing effort to create a more efficient permit application procedure, DEP has developed an online Permit Application Consultation Tool (PACT). For a news release explaining more about the tool, please click here. If you would like to go to the PACT Page, you may click here to use the tool or learn more about it.
EPA’s National Stormwater Calculator is Now Available to the Public
EPA’s National Stormwater Calculator is a desktop application that estimates the annual amount of rainwater and frequency of runoff from a specific site anywhere in the United States. Estimates are based on local soil conditions, land cover, and historic rainfall records.
It is designed to be used by anyone interested in reducing runoff from a property, including
• site developers,
• landscape architects,
• urban planners, and
The Calculator accesses several national databases that provide soil, topography, rainfall, and evaporation information for the chosen site. The user supplies information about the site’s land cover and selects the types of low impact development (LID) controls they would like to use. The LID controls that the user can choose are seven green infrastructure practices:
2. Rain harvesting
3. Rain gardens
4. Green roofs
5. Street planters
6. Infiltration basins
7. Porous pavement
Green infrastructure promotes the natural movement of water, instead of allowing it to wash into streets and down storm drains. Green infrastructure also has the added benefit of beautifying neighborhoods and increasing property values.
The stormwater calculator (SWC), like any model, estimates an outcome based on available information such as soil type, landscape and land-use information, and historical weather. These estimates can be affected by limitations on site-specific information and uncertainties about future climate. To better inform decisions, it is recommended that the user develop a range of results with various assumptions about model inputs such as percent of impervious surface, soil type, and sizing of green infrastructure. An update to the SWC, which will include the ability to link to several future climate scenarios, will be released by the end of 2013. Climate projections indicate that heavy precipitation events are very likely to become more frequent as the climate changes. Green Infrastructure can increase the resiliency of stormwater management approaches to a changing climate, and this update will allow users to consider how runoff may vary based both on historical weather and potential future climate. Please check with local authorities about whether and how use of these tools may support local stormwater management goals and requirements.