Mounding Calculations

[pcgarner]

In Massachusetts new stormwater management regs require that mounding calculations be performed under infiltration areas. HydroCAD does not do such calculations. Is there a simplified program commonly used that anyone can recommend?

Patrick C Garner Co., Inc.
Northborough, MA

 

[WL123]

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.

 

[tsli001]

Hey pcgarner:

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

thanks.

 

[pcgarner]

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

 

[WL123]

Here is a link to DEP's stormwater site,

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

 

[WL123]

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

In the link above look under, Stormwater Policies & Guidance

 

[psmart]

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


Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[pcgarner]

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