Applies To Product(s): Bentley StormCAD Version(s): 08.11.xx.xx Environment: N/A Area: Installation Subarea: Original Author: Scott Kampa, Bentley Technical Support Group Problem Description How do I activate a GEOPAK license inside StormCAD for MicroStation? The GEOPAk "applications" menu does not appear when opening StormCAD for MicroStation, so the Import/export GEOPAK menu items do not appear for StormCAD. Steps to Resolve Starting with the SELECTseries 2 release of GEOPAK, the Applications menu does not appear automatically. This needs to be available because GEOPAK needs to be activated in order for the import and export GEOPAK menu items to be available from the StormCAD menu. To fix this, you will need to add the -wsLoad_GEOPAK_SS2=1 switch to your StormCAD for MicroStation shortcut: 1) Navigate to the StormCAD for MicroStation shortcut 2) Right-click on the shortcut and select Properties 3) In the “Target” field, scroll all the way to the right 4) Add a space and then enter “-wsLoad_GEOPAK_SS2=1” 5) Click Apply, then OK. Then run the shortcut 6) Activate GEOPAK. Once this is complete the import/export GEOPAK menus should be available. After everything is activated the menus should look like this: This is the import menu This is the export menu

Applies To Product(s): Bentley StormCAD, OpenRoads Version(s): 08.11.04.54+ (StormCAD), SELECTseries 4+ (OpenRoads Environment: N/A Area: Output and Reporting Original Author: Jesse Dringoli, Bentley Technical Support Group Background What are some best practices and things to watch out for when exporting a StormCAD (or OpenRoads SS4+) model to GEOPAK and opening that model in GEOPAK Drainage? Before Exporting First, several improvements to the GEOPAK export feature have been added in the SELECTseries 5 release of StormCAD (and SELECTseries 4 of OpenRoads). If you have not done so already, it is strongly recommendated that you install SELECTseries 5 or (when available) higher. If you're using SELECTseries 4, these improvements are also included in the latest cumulative patch set. You can read about patches here: How do I download the water and storm sewer products? How can I find out when a new version or patch is available? Cumulative patch set frequently asked questions Also, GEOPAK Drainage tends to be more sensitive to any missing data input or other data entry issues compared to StormCAD. First, Validate the StormCAD model and ensure that the data entry is correct and that results are reasonable. Here is a list of other data entry problems to be careful of: 1) The Maximum Gutter Depth, and Manning's n (inlet) and Catalog inlet curb opening length fields for catchbasin nodes need to be set greater than zero 2) All Catchbasin nodes need to reference catalog inlets and need to have at least one attached catchment. Catchbasin nodes that act as junctions should be morphed into transitions or manholes. 3) No gutters should be leaving from an inlet in sag 4) All inlets on grade need to have a bypass gutter 5) The Tc of a catchment needs to be less than the maximum duration in the IDF curve 6) Elements that are topologically inactive will still be exported to GEOPAK. These can either be addressed in GEOPAK or deleted from the StormCAD model before export. Once the StormCAD or Openroads SS4+ design is finished, (or at an appropriate stopping point) export to GEOPAK. A GEOPAK drainage library is created and the GEOPAK drainage project is created. After Exporting After addressing these items, here are some suggestions for opening the resulting GEOPAK Drainage database (GDF) in GEOPAK Drainage. If you are having difficulty finding the option to Export to GEOPAK, see these two articles: How does StormCAD V8i integrate with InRoads, PowerCivil and GEOPAK? How do I activate a GEOPAK license inside StormCAD for MicroStation? After exporting to GEOPAK Ignore the exported library (DLB) and instead use one which you configure in advance with all the particulars worked out. Things which need to be checked/verified are: Make sure all the node library items are properly referencing the appropriate cell for display Make sure the link library items have necessary information configured. For example, the GEOPAK labeler typically depends on a description for labeling the pipe. This will not be populated in the exported DLB. Create a saved set of GEOPAK Drainage preferences and load this to the drainage project. This DPF file is reusable and is simply a shortcut to get the exported GEOPAK Drainage project operational quickly. The reason this is necessary is that the exported GEOPAK drainage project will not contain some settings which are not part of the StormCAD project. For example, GEOPAK uses slightly different junction loss calculations and the necessary constants will not be defined in the exported file. This really only matters if calculations are needed but it does generate some error message popups when opening the GEOPAK file. Open the GEOPAK Drainage project GDF file Once open load the preference file noted in 1B which also in turn loads the library noted in 1A In the GEOPAK Drainage menu: Components > Nodes > Update All Component > Links > Update All Open the GEOPAK Drainage labeler and complete your annotations as needed. If you need profiles for annotation or projection to a centerline, then these will need to be recreated inside GEOPAK Drainage. See Also Problems opening GEOPAK Drainage file exported from StormCAD

Applies To Product(s): Bentley StormCAD Version(s): 08.11.04.54 Environment: N/A Area: Output and Reporting Original Author: Jesse Dringoli, Bentley Technical Support Group Problem When exporting my StormCAD model to GEOPAK, the exported model will not open in GEOPAK drainage or appears to be incomplete. Solution First, several improvements to the GEOPAK export feature have been added in the SELECTseries 5 release of StormCAD (and SELECTseries 4 of OpenRoads). If you have not done so already, it is strongly recommendated that you install SELECTseries 5 or (when available) higher. If you're using SELECTseries 4, these improvements are also included in the latest cumulative patch set. You can read about downloading patches here: How do I download the water and storm sewer products? How can I find out when a new version or patch is available? Cumulative patch set frequently asked questions Also, GEOPAK Drainage tends to be more sensitive to any missing data input or other data entry issues compared to StormCAD. First, Validate the StormCAD model and ensure that the data entry is correct and that results are reasonable. Here is a list of other data entry problems to be careful of: 1) The Maximum Gutter Depth, and Manning's n (inlet) and Catalog inlet curb opening length fields for catchbasin nodes need to be set greater than zero 2) All Catchbasin nodes need to reference catalog inlets and need to have at least one attached catchment. Catchbasin nodes that act as junctions should be morphed into transitions or manholes. 3) No gutters should be leaving from an inlet in sag 4) All inlets on grade need to have a bypass gutter 5) The Tc of a catchment needs to be less than the maximum duration in the IDF curve 6) Elements that are topologically inactive will still be exported to GEOPAK. These can either be addressed in GEOPAK or deleted from the StormCAD model before export. See Also Best practices for working with GEOPAK drainage files exported from StormCAD

Hi I am going to connect the new system ( white lines) to the existing system (red line). Firstly, I have to analyse the existing system, Secondly, I should design the new system and finally , I should analyse whole system to see the existing system have enough capacity to capture the flow from the new system(white line). I know how to do them one by one, but in term of analyse whole of system I have some questions: what is the best approach for the topology of the system? I mean I have one topology for the Ex network and one topology for the new network how can I combine those as the third topology Thanks Hamid

You'll need to use selection sets to do this. For example MH-10 would be excluded in the selection set used in the annotation for Invert In 1, 2 and 3. MH-6 would be excluded from the selection set used in the annotation for invert In 2 and 3.

Applies To Product(s): Bentley WaterGEMS, Bentley WaterCAD, Bentley HAMMER Version(s): 08.11.xx.xx Environment: N/A Area: Modeling Subarea: Original Author: Scott Kampa, Bentley Technical Support Group Background After importing elements through ModelBuilder, it appears that some junctions are overlaying the pipes without splitting them, which is causing connectivity issues. Is there a way to fix this? Steps to Accomplish This happens because Modelbuilder will not split pipes. Modelbuilder will create a junction at the end of the pipe that touches the other pipe, but will not split it. There are two ways to connect them. Option 1 First, you can use a tool called Batch Pipe Split, which is found in the Tools pulldown. This allows you to split the whole model (or a seection set or subset of the model). This can be helpful when you have numerous pipe splits to do. After going to Tools > Batch Pipe Split, you will get the dialog above. You can choose to use the operating over the whole model or choose a given selection set of elements. You can also set a tolerance for cases where the junction is close to but not directly overlaying the pipe. When you click Okay, the operation will run. Once completed, you will get a notification of how many pipes were split When a pipe is split, it will create two new pipes. Both pipes will retain the properties of the original pipe, with the exception of the length of the pipe. The names given to the pipes will following the naming convention set in the Labeling tab of the Options menu (Tools > Options). Option 2 The second way to connect them is manually. If you right-click on the junction that overlaps the pipe, you can choose the option "Split". This will split the pipe as well. This is useful in you only have a handful of pipes you want to split.

Hi hamid I think I find out the way to help you by 1- go to analyses the existing system 2- drawn the new system and join to the existing system 3- make calculation type to design to whole system 4- make ( desing conduit ) field to false to all existing system conduits in flextables I hope I gave something toward the correct way

Hello TimZ, I did a quick test with a sample model and it seemed to work okay for me. The first thing I would do is make sure you have the latest version of PondPack, just to make sure you are completely up to date. If so, I may need to see the XML file to test this. There are two options for sharing your model files on Communities. If you would like the files to be visible to other members, compress the files into a zip file and upload them as an attachment using the ‘Advanced Reply editor’ before posting. If your data is confidential, you can follow the instructions in the link below to send it to us via Bentley Sharefile. Files uploaded to Sharefile can only be viewed by Bentley. communities.bentley.com/.../7079.be-communities-secure-file-upload Please post here with the name of the file so we know it is available. If you don't want to send the file, the alternative would be to simply add the file from your desktop or some local drive. Once you have added it to the Engineering Library, it will be available for future projects on your computer. Regards, Scott

Hello Hamid, You can make a selection set a number of different ways, such as by going to View > Selection Set. You can also select all of the elements you want to include in the selection set, then right-click and select "Create Selection Set." You can find more information on Selection Sets in the Help documentation. Once you have the selection set created, you can use it as a filter in Element Symbology. Edit your existing annotation to view the annotation properties. On the right side of the dialog is an item called "Selection Set." You can select the appropriate selection set for the annotation. When you apply this, only the elements in the selection set will have the annotation. The others will note. Note that filtering by selection set also works for color coding. Regards, Scott

(Please visit the site to view this file) Attached is the Zip. The .xml is called Chester County Rainfall Curve. As far as I know, my PondPack is up to date. It was patched on April 20th to update it to PondPack 08.11.01.56. One more question. Are there any tutorials on how to setup a PondPack model using ProjectWise?

Applies To Product(s): Bentley PondPack Version(s): 08.11.XX.XX Environment: N/A Area: Layout and Data Input Subarea: Original Author: Jesse Dringoli, Bentley Technical Support Group How can I import storm information from the catalog explorer of old versions? Background Versions of PondPack before V8i had different file formats to store storm and other library data. This data will not be converted automatically when upgrading to V8i. In previous versions, storm information such as rainfall curves, IDF curves, design storms, etc could be stored in the catalog explorer. This allowed the user to reuse these storms in any project. When you open a V9/10 model in V8i, any storm information saved in it will be imported. You can then export that information to V8i's engineering library for future use. Steps to Accomplish Option 1 For library data from version 9.0 or 10.X Go to File > Import > Pondpack 9/10 Engineering library data You will now need to browse to the .xml file, which stores the catalog explorer data that you wish to convert to V8i. This is the file cabinet icon seen in V9/10. If you are not sure where your xml file is located, open Pondpack V9/10, right click on the file cabinet representing the library item in question (in the catalog explorer) and choose "properties". The path to the .xml file will be displayed. After selecting the v9/10 XML file, you will then be prompted for a location to save the V8i format engineering library file. Choose a safe location and click OK. The library will be automatically registered in V8i's Engineering Library manager, so you can now begin using it with your projects. Option 2 For library data from version 8.0 and below Go to File > Import > PondPack 8.0 Engineering Library Data Browse to and select the .PLB file associated with your old library data. After selecting the v8 PLB file, you will then be prompted for a location to save the V8i format engineering library file. Choose a safe location and click OK. The library will be automatically registered in V8i's Engineering Library manager, so you can now begin using it with your projects.

Hello TimZ, When I try to import the XML file into PondPack's Engineering Library from ProjectWise, I get an error message that says: "The source is of a different engineering library type than expected." How was the XML file originally created? Was this an older PondPack V10 library file? As for tutorials on using PondPack with ProjectWise, there is a section in the Help documentation called "Working with ProjectWise". This is the first page for a couple of topics related to PondPack and ProjectWise. Regards, Scott

Applies To Product(s): Bentley StormCAD Version(s): V8i SELECTseries 5 (08.11.05.58) Environment: N/A Area: N/A Subarea: N/A Original Author: Terry Foster, Bentley Technical Support Group Overview The SELECTseries 5 release of StormCAD includes many new features and improvements. Let's explore each of these in detail. - Support for Newer Platforms and Operating Systems - Communities Search - RSS Feeds in StormCAD Standalone - Taps and Laterals - MicroDrainage Import - Visual changes to Flex Tables - Visual changes to Help Documents - HEC-22 3rd Edition Improvements - Batch Morph Tool - Show Terrain Model in Profile View - Show Tap Locations in Profile View Support for Newer Platforms and Operating Systems StormCAD now supports the following: Windows 7 SP1 (32 bit/64 bit)** Windows Vista SP2 (32 bit/64 bit)** Windows 8, 8.1 (32 bit/64 bit)** MicroStation V8i SELECTseries 3 (build 08.11.09.xx) AutoCAD 2014 (32 bit/64 bit)* AutoCAD 2015 (32 bit/64 bit)* ProjectWise V8 XM Edition or later * StormCAD V8i for AutoCAD license required. ** Note: Windows XP is not supported for StormCAD SELECTseries 5. Communities Search You can now go to our Be Communities website by going to Help > Bentley Communities. Once there you can do a search for the topic your are working on. Click here to go to a support solution that explains how to search for content. RSS Feeds in StormCAD Standalone Once you have been on the Be Communities website and created an account, you can sign up for RSS Feeds. On the Be Communities website, log in, then scroll down to the bottom and you will see, under Social Media, RSS Feed. Once you have signed up for the RSS Feed and chosen the subjects for your feed, when in StormCAD, you can go to Help > RSS Feeds to see a list of the wikis and/or forums on your feed. Note: You must have created a new project or have an existing project open in order to do this. After you select RSS Feed a box will open with your feeds. You can do a search by typing a search term in the search bar, or you can do a filter by clicking on the filter button. If you click on the settings button in the upper right corner, a dialog box will pop up. Here you can select a product's feed. Taps and Laterals Taps and laterals have been added to StormCAD V8i SS5. You can now add a catch basin with a lateral that taps into a main pipe without splitting the pipe. You have the option to choose whether to connect the lateral to a pipe. As show below, Tap-2 is on pipe P-PL2 without a split. MicroDrainage Import In StormCAD, you can now import MicroDrainage files. This will create a new project. The files types that can be imported are .sws, .ews, and .fws. Visual Changes to Flex Tables Some visual changes have been made to the flex tables. Check boxes are now shadowed. The text in boxes is spaced a little more and is much easier to read. Visual Changes to Help Documents The help documentation has visual changes that were made. In the past, the Index could not be used, but this is now functioning correctly. Improvements to HEC-22 3rd Edition Calculations Improvements were made to the GVF-Rational and GVF-Convex solvers on how junction losses were calculated. Improvements were also made to the calculations for near plunging conditions. Terrain Model in Profile View You can now view the terrain ground line (from an active terrain model) on profiles. Tap Locations In Profile View You can now view taps in a profile. They are shown as a circle on the profile. . See Also External Links Water and Wastewater Forum Bentley Technical Support KnowledgeBase Bentley LEARN Server

Applies To Product(s): Bentley SewerCAD Version(s): V8i SELECTseries 5 (08.11.05.58) Environment: N/A Area: N/A Subarea: N/A Original Author: Terry Foster, Bentley Technical Support Group Overview The SELECTseries 5 release of SewerCAD includes many new features and improvements. Let's explore each of these in detail. - Support for Newer Platforms and Operating Systems - Communities Search - RSS Feeds in SewerCAD Standalone - Taps and Laterals - Visual changes to Flex Tables - Visual changes to Help Documents - GVF Convex Solver Memory Management Improvements - HEC-22 3rd Edition Improvements - Batch Morph Tool - Show Terrain Model in Profile View - Show Tap Locations in Profile View Support for Newer Platforms and Operating Systems SewerCAD now supports the following: Windows 7 SP1 (32 bit/64 bit)** Windows Vista SP2 (32 bit/64 bit)** Windows 8, 8.1 (32 bit/64 bit)** MicroStation V8i SELECTseries 3 (build 08.11.09.xx) AutoCAD 2014 (32 bit/64 bit)* AutoCAD 2015 (32 bit/64 bit)* ProjectWise V8 XM Edition or later * SewerCAD V8i for AutoCAD license required. ** Note: Windows XP is not supported for SewerCAD SELECTseries 5. Communities Search You can now go to our Be Communities website by going to Help > Bentley Communities. Once there you can do a search for the topic your are working on. Click here to go to a support solution that explains how to search for content. RSS Feeds in StormCAD Standalone Once you have been on the Be Communities website and created an account, you can sign up for RSS Feeds. On the Be Communities website, log in, then scroll down to the bottom and you will see, under Social Media, RSS Feed. Once you have signed up for the RSS Feed and chosen the subjects for your feed, when in StormCAD, you can go to Help > RSS Feeds to see a list of the wikis and/or forums on your feed. Note: You must have created a new project or have an existing project open in order to do this. After you select RSS Feed a box will open with your feeds. You can do a search by typing a search term in the search bar, or you can do a filter by clicking on the filter button. If you click on the settings button in the upper right corner, a dialog box will pop up. Here you can select a product's feed. Taps and Laterals Taps and laterals have been added to SewerCAD V8i SS5. You can now add a catch basin with a lateral that taps into a main pipe without splitting the pipe. You have the option to choose whether to connect the lateral to a pipe. As show below, Tap-2 is on pipe P-PL2 without a split. MicroDrainage Import In SewerCAD, you can now import MicroDrainage files. This will create a new project. The files types that can be imported are .sws, .ews, and .fws. Visual Changes to Flex Tables Some visual changes have been made to the flex tables. Check boxes are now shadowed. The text in boxes is spaced a little more and is much easier to read. Visual Changes to Help Documents The help documentation has visual changes that were made. In the past, the Index could not be used, but this is now functioning correctly. Improvements to the GVF Convex Solver Memory Management Improvements have been made in how the GVF Convex Solver stores the data as it is computing the model. This will be especially notable in large models running in an EPS simulation with small time steps. Improvements to HEC-22 3rd Edition Calculations Improvements were made to the GVF-Convex solver on how junction losses were calculated. Improvements were also made to the calculations for near plunging conditions. Terrain Model in Profile View You can now view the terrain ground line (from an active terrain model) on profiles. Tap Locations In Profile View You can now view taps in a profile. They are shown as a circle on the profile. . See Also External Links Water and Wastewater Forum Bentley Technical Support KnowledgeBase Bentley LEARN Server

Applies To Product(s): Bentley WaterCAD, Bentley WaterGEMS, Bentley SewerGEMS, Bentley StormCAD, Bentley SewerCAD, Bentley PondPack, Bentley CivilStorm Version(s): 08.11.XX.XX Environment: N/A Area: Licensing Subarea: Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem Description When I try to compute my model I get a message that says something similar to, "The number of active pipes in this model exceeds the number of pipes allowed for your license. Calculations cannot continue." OR for StormCAD "The number of active inlets in this model exceeds the number of inlets allowed for your license." OR for PondPack "The number of active ponds in your model exceeds the number of ponds allowed for your license." Reason This can happen for two reasons: 1) Your license is only for a limited number of pipes, inlets, or ponds and the model cannot compute due to the license size 2) Your license is not being read correctly from your license tools. Steps to Resolve Your license is only for a limited number of pipes, inlets, or ponds The following steps use WaterCAD as an example, but works for all the Haestad line of programs: First check the size of the license the program is using by going to to Help > About WaterCAD and locate the area that says "size", so you can note this number. Locate the flextable for the particular element in question, as noted by the user notification. Open that flextable and note the number in the lower left corner of the flextable for this particular element (see screen shot below). This will allow you to determine how many of those elements you have in your model. If that number is greater than the number you have available in your license you will have to either: A) If your company has an ELS or SELECT Open Access license use the directions below under the "Your license size is not being read correctly by your software" section to choose a new default license size, which is described in step 5 B) Reduce that number by skeletonizing your model C) Reduce that number by exporting part of your model to make a new model so that both models are under the number of elements limited by the license OR D) Call your Bentley account manager and up your license count. Account managers can be reached by calling 1-800-BENTLEY and choosing option 1 for sales support. Your license size is not being read correctly by your software The following steps use WaterCAD as an example, but work for all the Haestad line of programs. If you know the license size for your software is larger than what is showing under the size area in the Help > About WaterCAD proceed to step 2. Go to Start > All Programs > Bentley > WaterCAD > Municipal License Administrator Click on Tools > Options > Verify (sometimes this button is shown as "test connection") - ensure that this verifies. If it does not, make sure that you are connected to the internet and that you typed the server name and activation key in correctly. Make sure there are no spaces before or after the server name or the activation key and note your server name. Click OK and go back to the main Municipal License Administrator window then click "Refresh configurations" and make sure the features column and size shows the correct information for your Haestad licenses. Click on the license that you would like to use and then click "make default". You will see a ">>>" in the "Default" column next to the license. Close the Municipal License Administrator and then browse back to Start > All Programs > Bentley > WaterCAD and click on "license management tool". Go to Tools > "Send Logs Now" - when this completes, go back and run this command a few more times to ensure that everything is synchronized. Open the program. If any warnings appear, acknowledge them, close the program and move on to the next step. Go back to the license management tool and perform the "send logs now" command again. Try to open the program and run your model to see if that resolves the issue. If not move on to the next step Now go to Start > All Programs > Bentley > WaterCAD and open the License Management Tool again. Go to Tools > Product Activation Wizard and activate your product. If you have a server name from step 3 of "SelectServer.bentley.com" you should check the option for "SELECT subscriber activating against a hosted (Bentley) SELECTserver". If you server name was "productactivation.bentley.com" you should select "Non-SELECT or Node Locked User". If your server name was something else you should select "SELECT subscriber activating against a deployed (local) SELECTserver." After you go through the activation try again to open your software and compute your model and if it still is not working please contact Bentley Support. See Also XM Licensing of Bentley Haestad Products

Applies To Product(s): Bentley WaterCAD, Bentley WaterGEMS Version(s): 08.11.03.17 Environment: N/A Area: Calculations Subarea: Original Author: Mark Pachlhofer, Bentley Technical Support Group Problem Description When I try to use a particular shapefile in the Thiessen Polygon Creator tool or in Loadbuilder I get an 'Index Out Of Range Exception' error that says: " Index was outside the bounds of the array." Why is this? Reason This message is usually due to the fact that the shapefile is a ZM, Z, or M shapefile. This indicates that the shapefile has 3 dimensions instead of the normal 2 dimesions of a regular shapefile. The 3rd dimension being height or elevation, hence the ZM, Z, or M. Steps to Resolve Download the latest version of the WaterCAD or WaterGEMS software Click here for download instructions This issue was resolved in a patch set for version 08.11.03.19, so downloading this version or a newer version elminates the issue. Or you have the option of speaking to your GIS professional and have them remove the ZM, Z, or M from your shapefile

Applies To Product(s): CivilStorm, PondPack, SewerGEMS, SewerCAD Version(s): V8i Environment: N/A Area: Modeling Subarea: N/A Original Author: Jesse Dringoli, Bentley Technical Support Group Overview The purpose of this technote is to clarify how the Modified Rational Method works, how it differs from the Rational Method (Used in Bentley StormCAD) and the differences in its implementation between Bentley PondPack and Bentley CivilStorm/SewerGEMS/SewerCAD. Background The Rational Method is traditionally a peak flow method used for storm sewer sizing. It predicts peak flows using the formula Q=CIA, where the intensity I is taken from an Intensity-Duration-Frequency (IDF) curve using the time of concentration of each drainage area. Bentley's StormCAD product uses this methodology to essentially calculate a steady-state simulation with peak flows. However, Bentley CivilStorm, Bentley SewerGEMS, Bentley SewerCAD and Bentley PondPack introduce the element of time and route hydrographs through the system. Therefore they cannot use the traditional Rational Method since it is only applicable to a peak flow/steady state conditions. Instead, each of these three programs offers a "Modified Rational" runoff method, which incorporates key Rational Method concepts (Q=CIA), but also generates a hydrograph. This introduces a common confusion among users of CivilStorm, SewerGEMS, SewerCAD and PondPack: Why is my flow much less than what I see in StormCAD or with the traditional Rational Method? The reason for this lies in the assumptions made when generating the Modified Rational hydrograph, compared to the single peak flow obtained with the rational method in StormCAD. With the traditional Rational Method, the peak flow of each drainage area (catchment) is based on its individual time of concentration. With the Modified Rational method, there is a single "storm duration" (and thus intensity) applied to all drainage areas. This is necessary because all routed hydrographs need to be based on the same storm. It would not be logical for hydrographs from different storm events to be routed together in the same system. Since the global storm duration needs to be greater than the highest catchment Tc, it's not possible for all catchments to be at their peak flow. For example, say you have five catchments with a Tc of 5 minutes and one catchment with a Tc of 10 minutes. The storm duration will need to be greater than or equal to 10 minutes. For the catchments with a Tc of 5 minutes their peak flow from the traditional Rational Method will be at a duration equal to their Tc. So the peak flow for those catchments with the modified Rational Method will be based on a time of 10 minutes resulting in a lower intensity and lower peak flow compared to the Rational Method. However, if you examine how the Modified Rational hydrograph is constructed you will see that a longer storm duration also results in a greater volume since the duration of the hydrograph is also based on the storm duration: Note: When looking for the “flow” of your Modified Rational method catchments in CivilStorm or SewerGEMS be sure to examine the full graph of flow over time (hydrograph) as opposed to simply looking at the calculated “flow” result. After computing the simulation your view will default to displaying results from time zero during which the catchment flow will be zero. What if I only have one catchment? Even if your model only contains one catchment setting the storm duration equal to its Tc may not achieve the worst-case conditions, since the volume of the hydrograph would be much lower compared to higher durations, as illustrated in the above graph. Couldn't I just force a steady state simulation by replacing the catchments with a fixed inflow obtained from the Rational Method? Removing the catchment and forcing a fixed inflow equal to the Rational Method flow may not be a good way to force a steady state condition in SewerGEMS, SewerCAD or CivilStorm. The flow from the Rational Method represents the peak flow occurring only for a moment in time. A fixed inflow of the same value would be like saying that the peak flow occurred for the entire duration being analyzed, which of course would have a large effect on routed volume. CivilStorm/SewerGEMS/SewerCAD Implementation In CivilStorm, SewerGEMS and SewerCAD, storm information and catchment input are the same as with the traditional Rational Method (StormCAD) - the user must enter an IDF curve for the model and Tc, area and C factor for each catchment. As discussed above, the difference is that a single storm duration must be entered , which is then used to determine the peak flow and duration of each catchment's Modified Rational runoff hydrograph. The duration in this case is stored in the Rainfall Runoff alternative and can be entered by going to Components > Global Storm Events. In this dialog, the Modified Rational storm duration is entered in the "duration" field next to each rainfall runoff alternative. The alternative will of course need to be assigned to the appropriate scenario being analyzed. The Modified Rational hydrograph will then be constructed per the diagram further above, using this duration. Note: do not confuse the "duration" here with the simulation duration. If you enter 24 hours, your Modified Rational hydrographs will extend to 24 hours and the peak will be based on the intensity on the IDF curve at 24 hours. How do I decide what duration to enter? The storm duration you enter is based on your engineering judgment. If unsure, you may want to check with your local reviewer to see if they require the use of a specific duration with the Modified Rational method. You may find that the Modified Rational method isn't an accepted hydrograph method and that something else like the Unit Hydrograph may be better suited for analysis (as opposed to design) in CivilStorm, SewerGEMS or SewerCAD. A trial and error process could also be used, to find which duration is best for your modeling case. Shorter durations may yield higher peak flows, but longer durations will yield higher overall volume. For instance, take a look at the below graph of runoff from a single Modified Rational method catchment along with overflow at a downstream node. As you can see, the duration that resulted in the highest overflow volume was 12 minutes, not 10. There is a balance between hydrograph volume and peak flow. I am required to use the Rational Method but I also need to quantify overflow, so I chose CivilStorm/SewerGEMS/SewerCAD As per above, you will need to be careful to recognize the differences between the traditional Rational Method that your reviewer is likely referring to and the Modified Rational method, which is not quite comparable. The Rational Method in StormCAD is typically used to size pipes for proposed systems to prevent flooding, whereas the Modified Rational method used by CivilStorm, SewerGEMS and SewerCAD is a hydrograph routing method more often used for analysis of existing systems experiencing flooding. If you have a license, you might still consider using StormCAD for this analysis. For example if you're trying to identify areas with flooding problems and then resize the pipes using the standard Rational Method, you will still be able to do both. StormCAD cannot quantify overflow and will reset the HGL to the rim elevation for flooded nodes, but you may find that knowing these locations where flooding is a problem may be good enough. In this case, it may then be appropriate to use the automated design tool along with the inherent Rational Method to size the pipes. If you find that your reviewer accepts other methods such as the Unit Hydrograph for analysis of flooding (as opposed to design/pipe sizing), you could continue using CivilStorm/SewerGEMS/SewerCAD with a change to the catchment's runoff method. Keep in mind that the Rational/Modified Rational method and Unit hydrograph methods are not comparable, so different peak flows are generally expected. Ultimately, it will be up to you as the engineer to decide how to proceed. PondPack Implementation Implementation of the Modified Rational method in PondPack is mostly the same, with one key difference: it automatically computes the "critical" storm duration for you, using an iterative process. This critical duration only applies to a single catchment and is based on the assumption that you are designing a pond which reduces outflow down to a predevelopment "target" flow. It is more common to use the Modified Rational method in PondPack for a single pond and catchment for this purpose, as opposed to using it with CivilStorm, SewerGEMS or SewerCAD with a storm drainage network. In contrast to CivilStorm or SewerGEMS where there may or may not be a pond, PondPack assumes that you will be designing a pond, with the criteria being that you wish the peak outflow from the pond to match that of the conditions before development. This is a typical requirement which is meant to reduce the impact of development on downstream hydrology. So, PondPack requires the same Rational Method input (Tc, Area and C) plus the predevelopment peak flow. It then constructs a series of Modified Rational hydrographs per the same process discussed above, overlaying an approximated pond outflow hydrograph. Two options are available for approximating this pond outflow hydrograph: Method I and Method T. These methods are shown in the below illustration . Method I assumes a linear outflow hydrograph, going from zero flow at time zero to the predevelopment peak where it meets the falling limb of the hydrograph. Method T's approximated outflow hydrograph follows a shape similar to the trapezoidal runoff hydrograph. For each storm duration tested PondPack finds the estimated storage volume, which is the shaded area above the estimated outflow hydrograph. This volume represents how large the pond will need to be in order to store the runoff hydrograph while still keeping the peak outflow below the predevelopment target (with the assumption that the pond you design will have an outflow hydrograph shaped like either the "I" or "T" method). The "critical" storm duration is the one that results in the highest storage volume (shaded area). This duration will be longer than the Tc, but typically less than an hour. PondPack stores information on this iterative process, which can be found in Report Builder, in the report entitled "Modified Rational Storm Calculations": In the example above, a storm duration of 0.383 hours resulted in the highest required storage volume of 0.155 ac-ft, and was selected as the critical storm duration. The critical Storm duration is then used to generate the postdevelopment runoff hydrograph for that catchment. (peak flow and duration). As mentioned in previous sections, this duration is normally greater than the catchment's Tc, so it will result in a peak flow less than the traditional Rational Method. From the illustrations above, it is clear that a storm duration equal to the Tc would result in a high peak flow, but a smaller volume. Basically volume becomes more of a concerned with pond design, whereas peak flow is more a concern with pipe sizing (such as with StormCAD, which uses the traditional Rational Method.) What if this is an existing system where the pre/post conditions are the same, or what if I don't care about the predevelopment peak flow? The underlying assumption with the iterative process that PondPack uses to find the critical storm duration is that you are designing a pond to attenuate the peak flow down to some target value. If you want to simply analyze an existing system without having to enter predevelopment information you should select "true" for "User Defined TD?" in the Modified Rational catchment's properties then enter the desired storm duration. This bypasses PondPack's iterative process of determining the critical storm duration, which would otherwise fail if the Pre and post information were the same. Remember that the storm duration you enter here determines the peak flow and duration of the runoff hydrograph. What if I have more than one catchment? If you have multiple catchments in your system the Modified Rational method may not be the right runoff method for you. Since PondPack will automatically calculate the critical storm duration differences in the catchments would likely result in different critical storm durations being chosen for each one. This would be like saying that different storms were occurring at the same time over the same site. Aside from accepting this inconsistency or choosing another runoff method, the only other option you have in this case would be to select "true" for "User defined Td" for each catchment then manually set them all to have the same storm duration. I changed the predevelopment information and my postdevelopment hydrograph changed. This doesn't make sense! One might be tempted to wonder why a change to the predevelopment target flow has an effect on the postdevelopment runoff hydrograph. Intuitively, what happens in the predevelopment conditions should not affect what happens in the postdevelpment conditions. However if you were to change the target peak flow for a Modified Rational catchment you will likely see a different runoff hydrograph on your model (different peak flow/duration). The reason lies in the iterative process that PondPack uses to calculate the critical storm duration. As mentioned further above, this process looks at the required storage volume for a range of storm durations and selects the duration that has the highest. The required storage volume is the area above the estimated pond outflow hydrograph, which is based on the target peak flow. So, the required storage volumes will change with a change to the target peak flow, and thus the critical storm duration may be different. The different duration would then result in a different postdevelopment runoff hydrograph. In other words, by changing the target peak flow, you're changing the way the pond outflow will need to be designed, which changes the storage volume you'll need for your pond, which means the storm that results in this critical storage volume may be different. If you wish to override the automatic calculation of the critical storm duration, you will need to force the storm duration by using the "User defined TD" option. How do I use the Modified Rational Method with PondMaker? When using the Modified Rational method, the pond design steps in PondMaker are slightly different. Since both the predevelopment and postdevelopment information is entered in the catchment you will not have separate pre and post scenarios. In the first step (Design Scenario Configuration), you will need to choose "Modified Rational catchment" for the "Target Flow/Volume source", then select the Modified Rational catchment for the "Target element". Computing step 1 will then populate both the pre and postdevelopment information in the worksheet. To replicate the estimated storage volume used by method I, choose “linear” for the option under the Estimated Storage step of PondMaker. What if some of the watershed is not being detained in the postdevelopment conditions? To account for a bypass/undetained flow with the Modified Rational method: 1) Perform a Q=CIA calculation, using only the area of the watershed that is not being detained in the postdeveloped condition 2) Subtract this peak flow value from your predeveloped peak flow. 3) Use the resulting value as a user defined target flow in the subarea, instead of the predeveloped. By doing this, a Modified Rational hydrograph can be generated, since the post developed peak will be greater than the predeveloped peak. What if I need to apply a different adjustment factor to the rational C for each return event? See below Support Solution on using the "C Adjustment" field and Hydrology alternatives to do this. http://communities.bentley.com/products/hydraulics___hydrology/w/hydraulics_and_hydrology__wiki/15965.applying-a-c-adjustment-factor-to-different-return-events.aspx Conclusion In summary, results from the Modified Rational Method are not necessarily comparable to those from the traditional Rational Method due to the introduction of the element of time. Although it may be useful for pond design in PondPack, you may find that the Modified Rational Method may not be appropriate for hydrograph routing in a storm drainage network (in SewerGEMS, CivilStorm and SewerCAD) and that another method such as SCS Unit Hydrograph is sometimes a better choice. The peak flow from the Rational Method in StormCAD is based on each catchment’s time of concentration. In SewerGEMS, SewerCAD and CivilStorm, it is based on a single storm duration that you must enter under Components > Global Storm Events. In PondPack, a critical storm duration is calculated automatically. See Also Product TechNotes and FAQs Haestad Methods Product Tech Notes And FAQs External Links Water and Wastewater Forum Bentley Technical Support KnowledgeBase Bentley LEARN Server

The .xml File was created by doing the usual steps when creating a rainfall distribution curve. In my PondPackV8i model, I go to components -> Storm Data. There I created a new Time-Depth using a dimensionless curve - Type II 24hr. I did that for each of my storm events: 1, 2, 5, 10, 25, 50, 100.

Thanks for your response, but, it still needs to spend time to select manually - one by one- for the manhole which have Elevation invert 1 , 2 , 3 and 4. I recommend you to include it into the next version or at least include it into the "Selection Set" > "Selection by Query" to user be able to do it faster. Thanks Hamid

Thanks Terry for the response Actually, I know how topology works, but, for this specific network, please let me know more how to model the third topology which is a combination of two other topologies. Thanks Hamid