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*TSS Event Mean Concentration = 15 mg/L
 
*TSS Event Mean Concentration = 15 mg/L
  
The above default values tend to be conservative values. For more information see the [[Overview for green roofs#Water quantity treatment|water quantity]] and [[Overview for green roofs#Water quantity treatment|water quality]] sections in the green roofs [[Overview for green roofs|overview]].
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The above default values tend to be conservative values. For more information see the [[Overview for green roofs#Water quantity treatment|water quantity]] and [[Overview for green roofs#Water quantity treatment|water quality]] sections in the green roofs [[Overview for green roofs|overview]] or the article on [[Calculating credits for green roofs|calculating credits for green roofs]].
  
 
==Model input requirements and recommendations==
 
==Model input requirements and recommendations==

Revision as of 18:45, 7 August 2013

screen shot of MIDS calculator for green roofs
MIDS calculator screen shot for green roof inputs and defaults.

Below is a summary of requirements, recommendations and other information for using the Minimal Impacts Design Standards (MIDS) calculator for green roofs. Links to MIDS pages and the MIDS calculator are included at the bottom of this page.

Model defaults

  • Media holding capacity = 0.33 cubic feet per cubic feet
  • Annual volume retained = 45%
  • Phosphorus reduction (particulate and dissolved) = 0%
  • TSS reduction = 85%
  • TSS Event Mean Concentration = 15 mg/L

The above default values tend to be conservative values. For more information see the water quantity and water quality sections in the green roofs overview or the article on calculating credits for green roofs.

Model input requirements and recommendations

Caution: The following are requirements or recommendations for inputs into the MIDS calculator
  • Media depth must be 4 inches or less
  • The top surface area of the green roof cannot exceed the total impervious area for the site

Information

Information: The following information may be useful in determining inputs for the MIDS calculator

Links to MIDS pages