Pond Design Software

[SCEngr1]

I would like to purchase or obtain either a free or inexpensive software to design detention and retention ponds. The software should also be able to design the outlet structure, outlet pipe, orfice size and spacing, spillway, etc.

Software mentioned in a recent pond design seminar that I attended listed the following:

1) SWMM (by EPA)(Free)
2) CivilStorm (Haested)($7,000-$25,000)
3) TR-55 (NRCS website)(Free)
4) HEC-HMS (Corps of Engrs)(Free)
5) HydroCAD ($195 to $1595)

Does anyone have a recommendation for one of two of these for designing small residential subdivisions (5 - 25 acres)?

 

[francesca]

I used Hydraflow Hydrographs, which is around $250. For retention ponds you have to "trick" it by giving it an outlet, but a 1' weir above the water surface elevation does the trick. (You should have an emergency spillway anyway so you can control where the water goes in a >design storm event.)

I found SWMM hard to get into, but probably worth it given that it can do water quality calcs. I didn't devote much time to it; I find most software pretty intuitive, but SWMM was anything but. (Same for HEC-HMS.)

I've also been briefly exposed to PondPac, StormCAD and WMS. I didn't find the first two any better than Hydraflow Hydrographs, and WMS is a GIS application so a lot more powerful and very expensive.

 

[cvg]

HEC1 can also be used, also free and is probably the software of choice in this region. note that for outlet pipe, orifice, spillways etc. Most hydrologic routing programs are not particularly good at doing the detailed hydraulic calculation necessary for rating these structures. I usually use good old Excel along with Brater and King's Handbook of Hydraulics to develop rating curves for outlets and spillways.

 

[geosavvy]

Ive been tinkering with SWMM. It's intruiging because of the price and alleged flexibility.

However, as far as I can tell, the methods it uses to calculate runoff are theoretical, and I get much smaller peak flow rates than I do with TR-55 using the "unit hydrograph" method.

You can specify one of three infiltration methods (CN Number, Green, or Horton); and you can specify one of three routing methods (Steady Flow, Kinematic Wave, or Dynamic Wave).

No matter which combination of these motherds I choose, my Peak Flow rate at the outlet is much much smaller than that predicted by the TR-55 method (using the same basin size and % impervious, avg ground slope, etc).

I want to know if I'm setting up the model incorrectly, or is TR-55 really that conservative??

I input the same rainfall event that I used in TR-55 (24-hr, Type II storm with 7.2 inches of rainfall).

I think there may be a way to input an inflow hydrograph into SWMM instead of using a Rainfall event and Runoff calculations. This way you could use something like TR-55 (if specfiied by the local governmetn, for example), then use SWMM to analyze your pipe network, basins, water quality, etc.

The program seems worthy of further probing for me; but its definately got a steeper learning curve than some others.

 

[psmart]

HydroCAD will do the hydraulics calculations, as well as the runoff, so you shouldn't have to resort to a spreadsheet. I think you'll find HydroCAD to be the easiest of these programs to use. Of course, I'm biased, so I urge you to form your own opinion with the free HydroCAD Sampler at

http://www.hydrocad.net/sampler.htm

 

[TerryScan]

I am a very happy user of Hydrocad. I have used many packages over the years, and still use some others from time to time for special situations, but Hydrocad is best and easiest to use for the vast majority of projects.

 

[SCEngr1]

Thanks for all the great feedback.

One other question, should we buy the 5-node ($195) version for the small sites (5 - 25 acres) that we normally deal with or would I need more nodes to account for more offsite drainage, etc.?

 

[psmart]

The number of HydroCAD nodes depends on the complexity of the model, rather than the acreage. You can always upgrade later for the same total cost. For details please see

http://www.hydrocad.net/nodes.htm

 

[LHA]

Everything by Haestad is more expensive than it needs to be, and no better than the competition. No idea why. Their output is long and haard to interpret, in my opinion. To be fair, this debate has come up here before, and others have disagreed with me.

TR55 will not route the outflow, only give you an estimated volume you will need for a depeaking target.

I am a very satisfied HydroCAD user, and unlike psmart, I have no incentive to steer you to it. It is simple to learn, and the output is the most compact and logical of any software I've seen. In fact the 5 node sampler might just work for the project you described. Give it a shot. I have 40 nodes, and only max'ed that out on one project; 575 acres, 6 watersheds, and lots of subareas which needed routed together. 20 nodes should be fine for 99% of the projects of the scope you've mentioned.

Engineering is the practice of the art of science - Steve

 

[SCEngr1]

A BIG THANKS again for all the help. We have purchased the 20-node version of HydroCAD.

....now, if I can accurately model all of the elements for our site.

 

[Callin]

My company renewed their license for Haestad's PondPack before I could let them know about HydroCAD.

PondPack input and output methods are terrible.

 

[sketchhwyman]

We used to have PondPack, and I would agree with the other posts here. It was overly complicated, the output was ridiculous (hundreds of sheets of just numbers), and it was overpriced compared to others.

We switched to Hydraflow Hydrographs and I am very happy with it. It is very easy to use and gives a nice output that is concise and goes great in a report. Correction to francesca's post - the cost is $595 now, but you buy it and own it without having to pay any yearly license fees, and free lifetime technical support is included.

Have never tried HydroCAD.

 

[queque]

Hydrocad can handle multiple outlets. Most other programs (HEC-1 ) cannot.

 

[NUMA23]

I also recommend intelisolves hydroflow. good stuff

 

[grovak]

I would stay with public domain software, as it is generally better documented; particularly with respect to changes between versions. HEC-1 has been superseded by HEC-HMS, but HMS does not produce a single output file with a copy of the input. Keep your HEC-1 around if you have it.
From NRCS, the Windows version of TR-55 does an actual outflow routing, unlike the earlier versions which just gave an estimate. It also is well documented.
Your best bet is SWMM (V5) free from EPA. It now has a GUI, but also produces a text-version of the input for your project file. It is well-documented, and has advanced features if you need them. E.g., by selecting dynamic wave routing, it will consider backwater effects, and can do multiple pond situations where you don't know in advance which way water will flow between ponds. It also produces tables, graphs of your choosing, and even animated profiles that let you watch the storm progress through the system if you wish.

 

[ptmoss]

I had always done hydrology manually with TR-55 until a company I was working for bought HydroCAD around 1988 or 89. I've basically used it ever since even. I worked for another firm for a couple years in early '90's and they used PondPack. I disliked it so much,but it was all they had. I used HydroCAD sampler while I was there for small projects whenever I could. After striking out on my own I purchased HydroCAD and have used it ever since, upgrading to 90 nodes along the way.

I also picked up CulvertMaster from Haestad which I use to document culvert analysis. HydroCAD models culverts fine but I prefer the report formats from a program solely devoted to culvert analysis. I have not, however, kept up with updates for CulvertMaster as I'm just not independently wealthy.

 

[SCEngr1]

I have been extremely happy with HydroCAD. It is easy to use and produces great Hydrographs and reports.

Some of the comments on this thread lead me to believe that Hydraflow might even be better. But, our company has already purchased HydroCAD and seems to be working for the small projects that we do (5 - 10 acres)with one detention pond.

I use the Land Desktop Hydraulic Manning Circular pipe calculator to size the storm pipes.

 

[Surcharged]

FFor simple projects its hard to beat Hydraflow for ease of se and great looking reports.

For complex projects with interconnected ponds i use XPSWMM. Its not the easiest to use and the reports arent great but it is a powerful tool.

I also like Culvert Master but I let my subscription lapse.