Win TR-55 vs Win TR-20

[amazonwells]

What are the advantages, disadvantages, applications for Win TR-55 versus Win TR-20. I am trying to decide which program to use for a stormwater routing design.

 

[geosavvy]

I've never used tr-20, but i've been messing around with tr-55 for a few months.

I think a lot of people use them together. Apparently Win tr-55 can output data that can be input into tr-20.

Tr-55 has limitations. It seems good for basic hydrology modelling of multiple drainage basins, but does not do any hydraulics and has limited storage modelling capabilities. Tr-55 is nice for calculating time-of-concentration, composite CN values, and generating scs runoff hydrographs and peak flow rates.

Hopefully other people will elaborate on these programs as I am curious to know more as well.

 

[LHA]

TR20 and TR55 use the same procedures, the SCS methodology.

TR55 will generate an inflow hydrograph only. You have to then apply it to a routing software.

TR20 will generate an inflow hydrograph, route it through storage and outlet structures and give an outflow hydrograph.

Most commercially available softwares - like HydroCAD, which has a free 5-node demo - will run TR55, then route the hydrograph.

Engineering is the practice of the art of science - Steve

 

[blueoak]

TR55 is a simplified version of TR20. It typically assumes you have a structure with a simple outlet. It does limited routing. With faster computers and better gis tools I think WinTR20 will become more standard. When I have had to use TR55, I will pull the hydrograph out for a better routing method.

As I tend to rant, I like HEC-HMS which has the same cost, but lets you have more flexibility and you can use your SCS methods and use the same model with other gages or info more smoothly.