HydroCAD is an integrated solution for the analysis, design, and
documentation of complete drainage systems using standard hydrograph techniques. Compared
to other programs that require several separate modules, HydroCAD is faster, easier to
use, costs less, and does so much more. Here is a brief overview:
On-Screen Routing Diagram
Exclusive on-screen routing diagram shows the interconnections between the
subcatchments, reaches and
ponds that make up each watershed.
This eliminates the need to manually prepare a flow diagram and makes routing changes a
snap. Automatic diversions are shown right on the
diagram as a secondary or tertiary outflow. And a "discarded" outflow is
available for exfiltration
losses. Hydrographs are automatically generated, summed and routed based on the diagram.
Design changes are automatically propagated throughout the system with the minimal
re-calculation feature, much like a spread-sheet. On-screen diagram also provides a
simple point and shoot interface for quick data entry, calculations, reports and
graphics. The diagram can also be annotated with text and custom images.
Generates complete runoff hydrographs using the SCS Unit Hydrograph procedure.
Provides full TR-20 runoff compatibility and improved accuracy over the
Extensive rainfall library includes SCS type I, IA, II, and III, plus Florida, Illinois,
and many other storms,. You can also download
local rainfall data and generate custom synthetic rainfalls, or setup custom
storms if required. Long time spans are
accurately handled with unlimited hydrograph points.
Santa Barbara Urban Hydrograph
Switch or compare
runoff methods at any time. The SBUH method can be used with any rainfall
distribution, and works together with all the other features described here.
Allows separate runoff calculation for pervious and impervious areas.
Curve Number Weighting
Each subcatchment allows an unlimited number of sub-areas, each
with fully automatic curve number lookup from the SCS/NRCS curve number
tables. Extensive on-line help includes complete listing of hydrologic
soil groups. Composite CN value can be calculated for all sub-areas,
or separated according to pervious and impervious areas.
CN values can be automatically adjusted for unconnected impervious areas. Curve number
usage can be reported on a project-wide basis.
Time of Concentration
Each subcatchment may have an unlimited number of flow segments,
using any combination of Tc procedures including TR-55 sheet flow, shallow
concentrated flow, upland method, lag method, channel flow, plus direct entry of circular, rectangular,
vee, trapezoidal, and parabolic channels. Travel time can also be
calculated for lakes and reservoirs.
Each project can have an unlimited number of rainfall events (2-year, 5-year,
water-quality, etc), allowing easy event changes and multi-event reporting.
Events can be automatically defined for most counties in the United States.
Rainfall reports display depth or intensity in tabular or graphical format.
Displays multiple storms at once for easy comparison. Works with all
standard and custom rainfall tables, plus
local rainfall data from NOAA, NRCC and other
rainfall editor makes it easy to create custom rainfall definitions, or create
synthetic storms automatically from local rainfall data..
HydroCAD includes a library of common unit hydrograph tables, including the SCS
UH (peak factor=484), Delmarva UH (PF-284), and many others.
Unit Hydrograph reports provide graphical and tabular representations, with the
ability to compare and create custom UH definitions.
Generates trapezoidal hydrographs using the Rational Method or Modified
Rational Method, with fully adjustable rise/fall rates. Automatic
curve management with frequency factors and critical-duration analysis.
Supports rainfall data from NOAA, NRCC, and other web sites. Switch instantly between SCS and Rational Method at any time
for a quick comparison of results. (Although the SCS method is preferred
for routing, Rational Method is sometimes used for pipe sizing.)
Land-Use Analysis and Pollutant Loading
sub-area can be associated with a specific land-use and pollutant
concentrations, allowing automatic land-use reporting and pollutant loading
calculations. Options include single-event loading or annual loading by
the Simple method. Details here.
A reach is frequently modeled as a flow segment within a subcatchment.
Alternatively, a separate reach routing may be performed for rectangular, vee,
trapezoidal, and circular channels. Other shapes can be modeled using a
custom cross-section (with constant or variable Manning's value), or by based on wetted perimeter
or gauge data. Several reach routing procedures are available, including
Muskingum-Cunge as used in the current Win-TR-20 release. Circular
channels (pipes) can be automatically sized for peak flow, or a full culvert
analysis is available by using a pond with culvert outlet.
Automatic hydrograph routing for any "pond," from a small catch basin
to a large lake. Basic pond routing is performed by the
storage-indication method (same as the Modified Puls method or Level
Pool routing). For more complex situations involving tailwater
dependencies, interconnected ponds, or even tidal tailwater effects, HydroCAD
also provides a dynamic storage-indication routing or
Automatically calculates pond stage-discharge curves for weirs (broad crested,
sharp-crested, V-notch, trapezoidal, rectangular, and custom), culverts (round, box,
arch or elliptical, under all flow
conditions), orifices (horizontal or vertical), orifice arrays (grates &
perforations), custom weir/orifice devices, overlapped (compound) weirs,
valves, tubes, siphons, skimmers, constant-flow outlets, and user-defined
devices. Devices may be combined to model complex devices like
stand-pipes, with automatic
transition from weir to orifice flow depending on head. Individual devices may be directed
to a secondary or tertiary outflow and routed separately to create a diversion.
Outlet devices may operate with fixed, differential, or dynamic (automatic)
Infiltration effects can be modeled as a pond with an exfiltration
outlet. Options include fixed flow, velocity, or conductivity, which
can be applied to the surface area or wetted area. To allow for impervious
areas, exfiltration may be limited to specific storage volumes and/or elevation
Pump & Siphon Routing
Complete pump modeling and hydrograph routing based on
the pump rating curve, on/off elevations, pipe loses, and even tailwater
effects. Also models self-priming siphons, with user-defined start and
break elevations under any tailwater condition, including dynamic tailwater.
Automatic storage calculations for common shapes
including cones, prismatic shapes, vertical and horizontal cylinders,
pipe storage, and arched chambers. Custom storage volumes may be entered
directly or calculated from surface areas. Any storage volume may be
adjusted for void space to allow for backfill, such as crushed stone.
Volumes may be embedded in each other to model complex storage
arrangements, such as stormwater chambers or perforated pipe buried in a stone bed.
Displaced volume can be automatically adjusted for thick-walled (concrete)
HydroCAD has built-in support for a wide range of prefabricated
storage chambers. Chambers can be
embedded in stone, with automatic calculation of overall stage-storage
relationship, including the displacement of thick-walled concrete chambers.
Chamber wizard performs automatic chamber
layout, modeling, and cost estimates for 100's or predefined chambers, including
automatic handling of end-caps, start/end chambers, and even pipe storage. Graphical and tabular reports make it easy to view and
compare available chambers, or create custom chamber definitions.
Special Pond Design Features
A special pond sizing report estimates the storage required to reduce pond
outflow to any desired rate. For compliance with water quality
requirements, detention time is calculated using the
center-of-mass and plug-flow methods. Other detention requirements
can be verified by using the tabular routing results.
Flexible Pipe Modeling and Automatic Sizing
HydroCAD can handle most any pipe geometry, including box, circular, elliptical,
and pipe-arch. Partially-filled culverts are easily modeled by specifying
the fill depth. Pipes can be automatically sized for pipe-full
conditions, or to achieve a specified headwater. Pipes are sized up and/or
down using any desired increment and minimum size.
A manual link provides the ability to enter any arbitrary hydrograph,
such as a pre-defined off-site flow. An import link will read a hydrograph
directly from a file. And an automatic link can interconnect separate routing
diagrams when analyzing large or complex drainage systems. A link can also be used to
establish a flow threshold, to scale a hydrograph peak or duration, to define
a tidal tailwater condition, enter an arbitrary table of tailwater vs. time, or
delay a hydrograph by a pre-set time. Details here.
Powerful Data Entry
Data entry is quick and easy with advanced features such as table editing,
built-in Manning's lookup table, and load/save from spreadsheet files.
Each screen is linked to a specific help page with full details on every
parameter and equation. Default values make it easy to handle common
day-to-day tasks, while advanced parameters (like adjustable Ia/S ratio) allow
modeling of special situations. Subcatchment data can be automatically
extracted from site plans using the Carlson
Graphics & Reports
Creates instant reports and graphics on your screen or printer. Report
Generator produces multi-page reports with automatic formatting, page headings, page
numbering, and project revision date. Project notes and detailed node notes
let you include
narratives and other documentation within each HydroCAD
report. Node comparison reports show existing vs. proposed conditions in
tabular or graphical format. Supports all Windows printer drivers, including plotters, fax,
and PDF drivers. See sample reports in PDF
format: Routing Diagram, Subcatchment,
Link, Node Listing
Flexible Input/Output Formatting
Independent selection of English or Metric units for data entry and reporting.
Units and decimal places are easily customized as
Imports external hydrograph files in a number of different formats.
Automatic import and conversion of TR-20 data files. Tabular watershed
import including subareas, curve numbers, and Tc data. Imports subarea
data directly from AutoCAD® or via Carlson Hydrology.
Reports and graphics can be exported in a wide range of file formats including TXT,
BMP, EMF, WMF, and JPEG. Hydrographs and other numerical results may be exported
in CSV format for use with spreadsheet applications. Automatic
export options allow data for an entire project (including all rainfall events)
to be automatically exported each time the project is opened, allowing dynamic
links with other software, database applications, or custom reports.
HydroCAD-10 also provides tabular export of watershed data, including subareas,
curve numbers, and Tc parameters.
Automatic Data Management
Projects can be stored on any local or network storage device, and can
be opened directly from Windows, as well as within HydroCAD. HydroCAD can
open multiple projects simultaneously, for easy comparison or transfer of
data. Automatic timed backup protects against system failures. Each project is stored in a single, compact ASCII file for easy data
management and exchange. This allows easy transmission as an email
attachment, which can be directly opened on any computer with HydroCAD
installed, including the free HydroCAD Sampler.
(Sampler users can view but not save projects with more than five
Runs on Any Personal Computer
Runs on virtually any PC under Windows 95/98/NT/ME/2K/XP/Vista/Windows7 or later.
Compact, sixty-second installation with no system
network compatible with flexible license pooling or
metered usage. Does not require other CAD
software, but includes extensive data import and transfer capabilities.
Pricing and ordering
What node capacity do I need?
Who uses HydroCAD?
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