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Hydrology Software

Hydrology Software

Hydrology Software

I have always gotten away with compex spreadsheets to do all of my hydrologic analysis. I typically work in southern california and typically work with the MOD Rat, modified rational method and rational method to do my hydrology studies. I usually do smaller land development projects where I need to size pipes, outlets, etc. I have decided that it may be time to graduate to some real software, but I can't make heads or tails of all the free, costs, and costs a lot software.

Does anyone have a preference on stormwater software and why?

SWMMM, StormNET, WMS, HEC HMS, Eagle Point, etc...

RE: Hydrology Software


My opinion...

For general and detailed hydrologic/hydraulic analysis and design (stormwater management and wastewater collection), I suggest using SWMM5 (Storm Water Management Model version 5). This is a completely free, open source, widely accepted, and widely used modeling system with a nice graphical user interface (GUI) available for MS Winows and compilable for other operating systems. It is easy to use and easy to learn. It is the primary software application I use for hydrologic, hydraulic, and water quality analysis, especially full system design - from single lot backyard channels to commercial complexes and residential subdivisions to complex watersheds of many square miles and different land uses. I use it for both hydrologic single storm event (10y 24h Type II, for example) and continuous watershed response simulation as well as simple and complex analysis/design. The user can choose from SCS/NRCS Curve Number, Green-Ampt, or Horton infiltration/runoff approaches. Open channels, closed conduits, curb/yard inlets, storage basins, weirs, orifices, and other hydraulic components are included in the model. It is very ease to learn and use (a tutorial is included), with excellent context-sensitive help. There are lots of example applications readily available for download and review/use. It is very stable software, never having crashed on me. It is equally applicable to stormwater management systems, sanitary sewer collection, and combined sanitary/stormwater sewers. I use it for roadway, culvert, channel, bioretention, basin, and other analysis, including design and subsequent permit application submissions.

For stand-alone culvert hydraulic analysis and design, I suggest using HY8 (FHWA Culvert Hydraulics). This is a completely free, widely accepted, and widely used software analysis package. The current version (7.0) with a nice graphical user interface (GUI) available for the MS Windows operating system. It is easy to use and easy to learn. Others you might try include FishXing (USFS), HLW (Dodson & Associates), and HydroCulv (HydroTools). These are all available for use at no fee. Only FishXing has features HY8 does not, but those are limited to aquatic habitat analysis (fish passage). SWMM5 can be used for stand-alone culvert hydraulic analysis and design as well.

For stand-alone non-eroding channel hydraulic analysis and design, I suggesting use HLW (Dodson & Associates Channel and Culvert Hydraulics) or ECMDS (North American Green's Erosion Control Materials Design Software). Both are available for the MS Windows operating system. HLW is available as freeware/trialware or by purchase (full version). The only difference between the HLW freeware/trialware and HLW full version that I can tell is printing, but you can copy and paste all analysis results so that's not much of a limitation! Still, HLW is very inexpensive (I think) and Dodson seems to be a good company, so you might wanna purchase it. ECMDS is freeware. Even though it is targeted at analysis of North American Green erosion blankets, you can also use it for other channel liner types (soil, riprap, vegetation). SWMM5 can be used for stand-alone channel hydraulic analysis and design as well, but doesn't directly perform depth-variable roughness analysis (though irregular/overbank channel flow analysis can be undertaken).

For stand-alone eroding channel hydraulic analysis and design, I suggesting use GSTARS2.1 (USBR Quasi-2D Channel Hydraulics and Sediment Transport), BriSTARS (FHWA Quasi-2D Channel Hydraulics and Sediment Transport), CCHE2D (NCCHE 2D Channel Hydraulics and Sediment Transport), or MMS (USGS 2D Channel Hydraulics and Sediment Transport). All are available for the MS Windows operating system. Make sure you use the GSTARS2.1 version as it has a pretty good GUI whereas later versions do not. I wouldn't use BriSTARS outside WMS as the interface is not user-friendly. Both CCHE2D and MMS have GUIs, but I think MMS is the much better GUI.

You can find links to all of these and more at "http://hhwq.blogspot.com"

...just my opinion.


tsgrue: site engineering, stormwater
management, landscape design, ecosystem
rehabilitation, mathematical simulation

RE: Hydrology Software

Be careful.  What you mean by ModRat, namely Los Angeles County's method is NOT the same thing most others on this forum understand by "ModRat". You can do the LA County method in a speadsheet ( as I have done ) as easily as any other method. As far as I know, none of the available free or commercial programs will do that method.

 They will do lots of other things though.  In general, try the free programs first.  Then try the lower cost programs such as HydroCad and Hydraflow next. Last, to save your money and sanity, go for the big bucks programs.  They may offer better tech support but they don't do anything more than some of the free ones.

good luck

RE: Hydrology Software

both aes and bondamin are written to do the california modrat method as well as written to do all the unit hydrograph methods using the exact parameters in the drainage manuals.  Whether it is Riverside, San Bernardino, Orange, LA or San Diego County - they have all the methods and criteria built in.

RE: Hydrology Software

For projects without interconnected ponds or significant backwater concerns, I like HydroCAD.  

RE: Hydrology Software

I work for a municipality and when things slowed down a bit last year I began the learning curve on a few of the free packages since I had a couple of big drainage basins that needed to be analyzed.

What I found is that SWMM is a really nice program.  However, it really doesnt seem built for commerical design work.  What I mean is that for most "simple" projects, you can perform the complete analysis serveral times faster using something like Hydrocad.  We purchased Hydrocad recently for that very reason.  It is very efficient when it comes to designing ponds and applying various storm events to the model.

HEC-HMS is also a pretty good program.  Its a little easier to setup than SWMM, but still more difficult (time consuming) than Hydrocad.  

Lots of people use Hydraflow Hydrographs - but I have no experience with it.  Being another piece of proprietary software, I'm sure it is built to perform basic analysis quick and efficiently.  

If I was in the private sector working for myself I would own Hydrocad but would also keep HEC-RAS, and SWMM installed on my computer.  I would likely use Hydrocad most often (for subdivisions and redevelopment projects), and HEC-RAS second for flood studies (unsteady breach analysis, etc).  I would probably only resort to SWMM if I needed to model some type of odd storm event, or needed to perform some water quality analysis. Of course SWMM can do some hydraulics computations too... so thats another consideration.

RE: Hydrology Software

I agree with geosavvy to a point.  My difference is that in my opinion, SWMM can not only do some hydraulics but basically ANY hydraulics...you just have to have the ingenuity to represent the situation in the model, which is not always intuitive.  I do agree that SWMM is not quick to set up, and not preferred by me for routine designs, but it's the ideal software for large interconnected systems, and especially useful if the system of interest includes weirs, orifices, pumps, or any combination of these appurtenances.  It most realistically represents the hydraulics but again, in my opinion is overkill for routine design problems.

I generally make a distinction between "modelling software" and "design software."  My definitions are that "modelling software is very robust and generally data intensive, but the results are very accurate (relative the the data you input of course).  The design software is quick, fairly easy to use, and somewhat conservative providing generally acceptable results.

The benefits of SWMM are that it's hydraulics are based on volumes and time, using St. Venant's equations for dynamic flow through the system.  That's about as far as I'm able to explain with respect to the hydraulic routines in SWMM, but the benefits of this type of calculation are that it essentially performs a "routing" through, not only your storage features, but through every structure in the model.  

I've not used the basic EPA SWMM package although I've read that the latest version (I believe is 5.?) has a pretty good graphical interface and rivals the proprietary interfaces.  I've used several of those and prefer the XP software version over other proprietary interfaces.  I hope to try the new EPA SWMM soon and be able to get rid of the costly proprietary interfaces.   

RE: Hydrology Software


A commercial package you might be interested in is MIDUSS (http://www.alanasmith.com). I still suggest using SWMM5 as your standard analysis H&H software application, however. All software takes some time to learn, but most engineers I know have learned SWMM5 in less than a day and been efficient with it in a few days. I've tried HydroCAD, Hydraflow, StormCAD, HEC-HMS, HYDRAIN, and others. Years ago I used some of these for analysis/design, but haven't used any of them in at least the past 2 years as SWMM5 has developed into such a good package.

Again, only my opinion. You might find another software application more suits your needs.


tsgrue: site engineering, stormwater
management, landscape design, ecosystem
rehabilitation, mathematical simulation

RE: Hydrology Software

I know of a consultant who did a basin-wide sanitary sewer model in SWMM instead of SewerCAD due to SewerCAD's inability to model an ARV. The basin was on the order of maybe 50 pump stations, several hundred manholes and 1,000 pipes. We used SewerCAD and had one heck of a time doing a 24-hour simulation on the trunk FM that had the control point shift depending on how many pumps were running and ended up with about 12 models to their two (existing & proposed). SWMM is certainly very powerful, but sometimes you don't need an M1 Abrams, you just need a small revolver.

RE: Hydrology Software

I too use Excel and Hydro-cad mostly.

Chris Erichsen
GeoIntel GIS

RE: Hydrology Software

a star for the extremely good question that has raised some great answers... Dik

RE: Hydrology Software

I recently started doing some work in Southern California. I don't understand why the hydrology has to be so convoluted that the engineering community there does not understand it. The process could so much simple if they would just simply publish a unit hydrograph that is to be used. Riverside county does this and it makes a lot easier to input it into a computer model. If anyone wants this one for HydroCad I will freely give it to them. San Bernardino does not. What they call a synthetic unit hydrograph is really the hydrographic for that job and to do 1000's of hand calculation to get there in this age of computers makes no sence. The Modrat rational method that LA uses is indeed easy to make a spreadsheet for, but it is not suitable for routing anything through a detention basin. Also it is not the same modrat that is generally used in the elsewhere. I have found that for most everything engineering thing in CA they have reinvented the wheel and for no good reason.

RE: Hydrology Software


Friends of mine have had some success getting the LA MODRAT method approved in Riverside County. That success has not been universal, however, as every City, town, hamlet and ground squirrel burrow in Riverside County seems to believe wheel reinvention is the state of the art. La Quinta is especially maddening.

Using LA MODRAT produces results comparable to the NRCS and SBUH unit hydrograph methods, on our experience. We use rhe published storm data in the Riverside County Hydrology Manual ( 1978) so results cannot vary appreciably regardless of the method used.

For routing through retention/detention ponds, trenches, etc.we use HydroCad or Hydraflow Hydrographs with good, and easy, success.

"This ain't rocket surgery for cryin' outside!"

good luck

RE: Hydrology Software

Good Topic,
I've always liked hydrocad and HEC-1/HEC-HMS.  I'll actually be in Davis, Ca next week taking a HEC-HMS at HEC.

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