Owner's Manual - HydroCAD Stormwater Modeling Software

1 1H y d r o C A D Stormwater Modeling SystemVersion 10 Owner's ManualCopyright 2011 HydroCAD Software Solutions LLC. All rights is a registered trademark of HydroCAD Software Solutions trademarks are the property of their respective Software Solutions Box 477 Chocorua, NH 038171-800-927-7246 Tel: (603) 323-8666 Fax: (603) 978-0-913633-15-16182 rev. 7/27/1123 CopyrightThis publication and the associated Software are copyrighted, withall rights reserved to HydroCAD Software Solutions LLC. ( HSS ).Your rights are subject to the limitations and restrictions imposedby international and copyright laws. No part of this publicationmay be reproduced in any form or by any means without writtenpermission from publication incorporates trademarks which are the property ofHSS.

2 You may use these trademarks only for the purpose ofidentifying the products of HSS, in accordance with acceptedtrademark practice. Such use of any trademark does not give youany rights of ownership in that TrademarksAutoCAD is a registered trademark of Autodesk, Inc. Windows,Windows 7, and Vista are registered trademarks of Microsoft AgreementThe accompanying computer Software is licensed, not sold, to you byHSS, under the terms of the license agreement shown in thesoftware s installation program. By installing or using the softwareyou agree that you have read the license, and that you accept of WarrantyAlthough HSS has used its best efforts in the compilation andpreparation of this publication, it is provided as-is , with nowarranties, express or implied, that the publication or associatedsoftware are MAKES NO WARRANTY, EXPRESS OR IMPLIED,REGARDING THE PERFORMANCE OF THIS PUBLICATION ORTHE ASSOCIATED Software , OR ITS MERCHANTABILITY ORFITNESS FOR A PARTICULAR PURPOSE.

3 HSS SHALL NOT BELIABLE FOR ANY DAMAGES ALLEGED TO ARISE FROM THEUSE OF THIS PUBLICATION OR THE ASSOCIATEDSOFTWARE, INCLUDING LOSS OF REVENUES OR DAMAGE TOPROPERTY, PERSONS, OR INTERESTS, INCLUDING BUSINESSINTERRUPTION OR LOSS OF BUSINESS PROFITS, EVEN IFHSS IS ADVISED OF THE POSSIBILITY OF SUCH a b l e o f C o n t e n t sIntroduction to 11 Section 1 - What is HydroCAD ?.. 13 Section 2 - HydroCAD Features and 15 Current Features .. 15 Features added in 17 Features added in 18 Features added in 19 Features added in 20 HydroCAD User's 21 Section 3 - About this 23 Finding the Information You Need .. 23 Conventions Used in This 23 Section 4 - Installing 25 Installation .. 25 License Pooling.

4 26 Section 5 - Using 27 Operating Sequence .. 27 What is a Project ? .. 28 Starting HydroCAD .. 28 The HydroCAD Screens .. 29 The Routing Diagram .. 30 Working With Nodes .. 32 Automatic Calculations .. 32 Calculation Settings .. 33 The Message Window .. 33 Printing Reports .. 34 Units of Measure .. 34 Section 6 - HydroCAD Project 35 Project Storage .. 35 Predefined Projects .. 35 Default Project Settings .. 35 Read-Only Projects .. 36 Editing a Project File .. 36 Creating Project Files with Other Software .. 366 Section 7 - Data 37 Tabular Data Import .. 37 Automated Tabular Import .. 37 Importing a TR-20 Data File .. 37 Importing Data from autocad .. 38 HydroCAD Technical 39 Section 8 - Understanding 41 What is Stormwater and why does it need to be modeled?

5 41 Understanding 42 Section 9 - Units of 43 Section 10 - Rainfall 45 Intensity-Duration-Frequency Data .. 45 IDF Library .. 46 Synthetic Rainfall Distributions .. 46 Rainfall Library .. 47 Custom Synthetic Rainfall Distributions .. 47 Importing TR-20 Rainfall Data .. 47 Rainfall Events .. 47 Unit 48 Unit Hydrograph 48 Section 11 - SCS Curve 49 Curve Number Effects .. 49 Curve Number Lookup 49 Composite Curve Number .. 49 Unconnected Impervious 50 Separate Pervious/Impervious Runoff .. 50 Adjustments for Antecedent Moisture Condition .. 51 Section 12 - Time of 53 Lag/Curve Number Method .. 53 Sheet Flow 54 Shallow Concentrated Flow .. 55 Channel Flow .. 55 Travel Time Through Lakes and Reservoirs.

6 56 Other Tc Procedures .. 56Tc Restrictions .. 567 Section 13 - SCS Unit Hydrograph 57 Data 57 Runoff Generation .. 59 Special Considerations .. 61TR-55 and the Tabular Method .. 62 Section 14 - Santa Barbara Urban 63 Runoff Procedure .. 63 Special Considerations .. 64 Section 15 - Rational 65 Runoff Procedure .. 65 Special Considerations .. 66 Frequency Factor .. 66 Section 16 - Reach Routing 67 Reach Routing Curves .. 67 Reach Routing Limitations .. 69 Reach Routing Table .. 70 Reach Routing Methods .. 71 Storage-Indication 71 Muskingum-Cunge Method .. 72 Simultaneous Reach Routing .. 75 Effects of Reach Routing .. 76 Section 17 - Pond Storage 77 Prismatoid Storage .. 79 Vertical Conic Storage.

7 80 Round Pipe Storage .. 81 Box Pipe 82 Elliptical and Arch Pipe 82 Parabolic Arch Storage .. 83 Prefab Chamber Storage .. 84 Custom 858 Section 18 - Pond Hydraulics 87 Sharp-Crested Rectangular 88 Broad-Crested Rectangular 89V-Notch Weir .. 90 Trapezoidal Weir .. 91 Weir Rise .. 92 Custom Weir/Orifice .. 92 Asymmetrical Weir .. 93 Submerged Weirs .. 94 Dam Breach .. 95 Rectangular Orifice in a Vertical 96 Rectangular Orifice in a Horizontal 97 Orifice Discharge Coefficient .. 97 Circular Orifice .. 98 Orifices Under Low-Head Conditions .. 99 Modeling a Grate .. 99 Culvert Flow .. 100 Tube & Siphon Flow .. 102 Constant-Flow Outlet Device .. 104 Special Outlet Device .. 105 Pump Calculations .. 106 Exfiltration Calculations.

8 108 Tips for Using Exfiltration .. 110 Discharge 111 Discharge Velocity .. 111 Section 19 - Pond Routing 113 Stage-Storage Calculations .. 113 Stage-Discharge Calculations .. 113 Compound Outlet Devices .. 114 Pond Routing Procedures .. 115 Storage-Indication 115 Additional Routing Features .. 117 Dynamic Storage-Indication Method .. 117 Simultaneous Pond 118 Tailwater 119 Reverse Flows .. 120 Section 20 - Detention 121 Section 21 - Hydrograph 1239 Section 22 - Link 125 Basic Applications .. 125 Advanced Settings .. 125 Elevation Settings .. 126 Link Routing Procedure .. 126 Using a Link to Model a Large Watershed .. 127 External Hydrograph Files .. 128 Hydrograph Export Settings .. 128 Section 23 - Land-Use Analysis & Pollutant 129 Section 24 - Calculation 131 Section 25 - Frequently Asked 143 Section 26 - 147 Appendix A1: Hydrologic Soil Groups.

9 149 Appendix A2: Runoff Curve Numbers .. 150 Appendix A3: Curve Number Adjustment for AMC .. 154 Appendix B1: HydroCAD Rainfall Library .. 155 Appendix B2: SCS Synthetic Rainfall Distributions .. 157 Appendix B4: Rainfall Depth Maps .. 159 Appendix C: Manning's Number Table .. 162 Appendix D1: Broad-Crested Weir Coefficients for Sharp-Edged 164 Appendix D2: Broad-Crested Weir Coefficients for Assorted Profiles .. 165 Appendix E: Culvert Entrance Loss Coefficients .. 166 Appendix F: Sheet Flow Roughness Coefficients .. 167 Appendix G: Velocity Factors .. 168 Appendix H: Cross-Sectional Area & Perimeter Equations .. 17110 Introduction to HydroCAD11 Introduction to HydroCADThis section contains general informationabout HydroCAD and the capabilities to HydroCAD12 Introduction to HydroCAD13 Section 1 - What is HydroCAD ?

10 HydroCAD is a Computer Aided Design program for Modeling the hydrology and hydraulics ofstormwater runoff, commonly referred to as H&H. HydroCAD uses procedures developed by theSoil Conservation Service (now the Natural Resources Conservation Service), plus a wide range ofother standard H&H calculations, to produce a fully-integrated, interactive Stormwater modelingsystem. Although HydroCAD was initially developed for use in the United States, it has globalapplication due to its ability to incorporate local rainfall and soil is commonly used to generate runoff hydrographs for a given watershed and study theirflow through a drainage system consisting of natural and/or artificial components. This allows thedesigner to verify the adequacy of the drainage system, or to predict where flooding or erosionproblems are likely to occur.