Here is a simple on-line one,

http://www.groundwatersoftware.com/calculator_9_hantush_mounding.htm

I use "Modret" to iterate the mounding calc's using output from "HydroCAD" hydrographs. However, "Modret is a pain in the "A**" and sometimes does not work. They should have a better method.

Mainly you need to do the mounding to figure the time it take to empty you detention area. All detention basins mound. There should be a general rule or chart to use provided by DEP to make it easier.

Hey pcgarner:

I am a EIT in mass, Can you tell where is the new reg. saying we need to the mounding calculation?

thanks.

Read Vol III of the revised Stormwater Management regs (now a regulation, not a policy). Any infiltration device used to modulate a 10-year or greater storm must have mounding calcs performed.

Patrick C Garner Co., Inc.
Northborough, MA

Here is a link to DEP's stormwater site,

http://mass.gov/dep/water/laws/policies.htm#storm

I couldn't find a way to edit my post, so,

In the link above look under, Stormwater Policies & Guidance

The Hantush procedure is on the wish-list for the next HydroCAD release.  Other suggestions are always welcome.
 

Peter Smart
HydroCAD Software
www.hydrocad.net
 

Peter,
The sooner the better! You'll have engineers all over the state cheering you. And yes, Hantush is the DEP-recommended methodology.

Patrick C Garner Co., Inc.
Northborough, MA