NetSTORM Toggle Menu

NetSTORM is CDM Smith's software for hydrologic data analysis and collection system model pre- and post-processing. The software performs:

  • Storage – Treatment – Overflow Runoff Modeling
  • Precipitation intensity – duration – frequency (IDF) analysis
  • Time series aggregation and synthetic disaggregation
  • Data acquisition and formatting from US National Weather Service sources
  • SWMM and MOUSE calibration and statistics tools

NetSTORM adapts selected algorithms originally included in the U.S. Army Corps of Engineers HEC-STORM program and extends the STORM methodology to simulate systems with multiple control structures. It has been used in CSO, SSO, industrial stormwater, and pump station planning studies worldwide. NetSTORM was used to establish stormwater detention basin design guidelines for the California Stormwater BMP Handbooks. NetSTORM is designed for Windows operating systems. It operates in SI and English units. It is available for free download and use.

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SWMM Resources

Internet resources discussed in the CDM Smith University Introduction to SWMM class are listed here

SWMM SWMM 5 SWMM-Users list SWMM-Users archives Legacy versions Bob D's pages SWMM4 help SWMM4 manuals Example runoff calcs
Met Statistics NWS rainfall atlases NetSTORM atlas Monthly evaporation Precip normals Wind speed State climate offices Canadian IDF
Met Data NOAA NCEI NCEI viewer LCD Community Rain Network KNMI Explorer USU viewer Wunderground MesoWest California NOAA Global Daily NOAA metadata
Hydrology US Water Dashboard Soils calculator Horton parameters Green-Ampt parameters Evaporative depth NWS river hydrology USGS hydrography tracing US soils Modified G-A
Hydraulics Tide data Natural channel Manning’s N Open channel Manning's N Closed conduit Manning's N FHWA Manual HEC-22 (form loss coefficients etc.) NCHRP Culvert Losses USACE Sea level calculator Normal flow spreadsheet
Guidance EPA CSO Guidance for Monitoring and Modeling EPA Model Development Guide CIWEM Code Of Practice NRCS Engineering Handbook USACE manuals New Zealand Modeling Guidelines
Vendors Aquanuity AquaTwin AutoDesk InfoWorks ICM Bentley SewerGEMS CHI PCSWMM DHI MIKE+ Innovyze XPSWMM
Freeware EPA SSOAP EPA GI Toolkit HEC-SSP NGS coordinate conversion NOAA VDatum NOAA WCT USGS Hydrologic Toolbox USGS PeakFQ USGS StreamStats
Open Source EPA repository EPA GUI repository swmmtoolbox (Python) MatSWMM pyswmm OWA SWMM swmmr
GIS Global hydrography US National Map Viewer USGS TopoView USGS Historic Topo Explorer USDA Soils Nautical charts David Rumsey maps
Videos Ted Cleveland (Texas Tech) EPA SWMM Bob Dickinson (Innovyze) (InfoSWMM and EPA SWMM) Bentley Introduction to SWMM (EPA) Hydrology 101 with XPSWMM


NetSTORM is provided as-is for the public. Comments and questions directed to Mitch Heineman or Ajay Prasad at CDM Smith are welcome, but no support is promised, other than through CDM Smith. Papers and reports referencing NetSTORM are listed below. Refer to the help file or the Introduction to NetSTORM PDF included with the program's installation for help getting started. Both are installed to the software directory (e.g. \program files\netstorm).

Version history

- add 0.1 resolution option for metric data disaggregation
- fix bug in SWMM Read routines affecting read of elements.dat file
- fix bug for long folder names in Global Hourly data
- fix bug in IDF output for display of powers of 10 (10.0 was displaying as ****)
- fix bug for pre-1900 dates in Annual Series IDF plots
- improve IDF report appearance
- User-specified Gage info files for IDF analysis no longer look for country and elevation. Include gage info reference at top of rainfall file, e.g., # "C:\myfiles\gageinfo.dat"
Metadata file contains one or more gages with format:
;gageID, Name, Latitude, Longitude
RG1, "Washington School", 39.3000, -77.9000
- ASOS data acquisition updated to obtain files from NOAA website instead of discontinued FTP; minor interface improvements for reading ASOS

- Graph annual maximum series for annual totals and selected durations; exclude missing years
- Obtain metadata for non-NOAA rain gages from filename following # in file header
- Mann-Kendall trend test added to IDF and annual totals
- Optionally use standard IDF constraint correction factors based on NOAA Atlas 14
- Global hourly data download also saves temperature file

- Many improvements to IDF output tables
- Improved algorithms for reading 1-minute ASOS and Global Hourly NOAA datasets to better match certified hourly data

- New menu item to download data from NOAA's 30,000-station Global Hourly precipitation database (Read | Get NOAA Global Hourly)
- Improved formatting and metadata for IDF output

- IDF: HTML-formatted output, frequency estimates extended to 1000 years, confidence intervals added, station info reported from NOAA HOMR database
- IDF: Constrained observation adjustments for 1-168 hour GEV
- IDF: optional start/end years
- STORM: user-specified DWF

- Hourly precip can be downloaded data from NCDC web service directly from a dialog box in the software. - Hourly rainfall synthetic disaggregation accommodates new NCDC time format (midnight = 0:00)
- Graphing capabilities added to the rainfall IDF tool
- Various routines refactored for clarity and improved error handling
- ASOS 1-minute data conversion restored to functionality
- SWMM binary output reader (CSReporter) updated to read both SWMM 5.0.22 and 5.1 output correctly
- CSReporter cross-tab functionality updated to report node inflows instead of depth
- Read NCDC Quality Controlled Local Climatological Data (QCLCD) forms
- Windows 32- and 64-bit compatibility
- CS plotter can plot multiple timeseries
- CSReporter.mdb has changes to tables "Conduit Hydrographs", "Junction Hydrographs", "_ConduitSmooth" and "_JunctionSmooth".
-LegendName field added for displaying custom legend names on calibration plots

- Windows 7/8 32- and 64-bit compatibility
- CS plotter graphics improved, Willmott index of agreement added
- IDF output identifies US COOP and WBAN station names
- new NCDC US hourly format added
- Read dialogs simplified
- various old precipitation data formats dropped
- Powerpoint macro to import calibration plots

- Updates to CSInterfacer - Bug fixes to CSReporter - Updated help file - CSReporter - Reads SWMM Binary Out files
- CSReporter - Reads and plots multiple modeled timeseries
- CS Interfacer - Includes tool for data exchanges among MOUSE, HSPF SWMM etc. See CS Interfacer for more information
- IDF Analysis - Bases interevent times on minutes, not just hours between events
- IDF Analysis - Uses fitted return period to IDF event listings
- IDF Analysis - Excludes missing periods from period of record to improve plotting positions and IDF statistics
- Rainfall analysis - Implements character gage names
- IDF Analysis - LP-III fit for flow data (cutoff≠0)
- Rescale and Reformat - Pad Zeroes handles multiple gages

- CSReporter - Updates MOUSE data import routine to run faster
- CSReporter - Import timeseries for upto 1000 elements from MOUSE results file
- CSReporter - Added functionallity to import Subcatchment Hydrographs from SWMM report file

- Fix SWMM5 data import in MGD for CSReporter
- Smoothing function to use GageInterval in Gages table for CSReporter
- Fix for CSO Statistics
- Calibration Event Summary export to ModGage.xls
- Calibration Hydrograph: Added markers to observed data timeseries plot
- Fix problem reading SWMM 5 output files
- Fix problem in Transform|Rescale/Reformat
- Fix problem in loading SWMM5 output files to CSReporter
- New C# code base replaces previous VB6 version.
- Complete revamping of SWMMReporter. Now CS Reporter
- Multi-structure NetSTORM modeling and Gradually Varied Flow calculator omitted.
- Correct error in sub-daily aggregation for last record of a gage
- Handle pre-1900 dates properly in IDF analysis
- Read new GHCN format
- Read USHCN WTEQ data
- Update USHCN Monthly to Version 2 dataset
- Ignore brackets in raw ASOS data
- Improve Compute Snowmelt output
- Known issues: Transform|Rescale/Reformat not working, SWMM5 output files can't be loaded to CSReporter

- Read | Precipitation imports NWS 1-minute ASOS DSI 6406 precipitation
- Read | US Historical Climatology Network imports international Daily GHCN data
- CSO Stats function in SWMM reporter counts events by overflow occurrence or by storm
- Tables _CSOStormsCalc, CSOStorms, _ModelOutfallByStorm, _CSOStatsByStorm added to SWMMReporter.mdb
- SWMM Plotter plots flows in CFS or MGD
- Observed and modeled statistics can be switched off in SWMM Plotter graphs
- User can modify SWMM Plotter output folder location from dialog
- Offset field in Gages table is subtracted from observed junction depth timeseries
- Data grids displaying SWMM output timeseries hidden to fix 'Out of Memory' error
- ImageImport.pptm sorts plots in ascending order
- Known issue: IDF analysis ignores multiple file requests

- SWMM Reporter can read subcatchment data from the SWMM report file
- New tables Subcatchment Hydrographs and WellData were added in SWMMReporter.mdb file
- Read NCDC surface airways data formats as formatted by UCAR (TD-14 and TD-3280)
- Removed tooltip option which caused error in ImageImport.ppt
- Read HydroData vertical bar (|) delimited precipitation format
- SWMM Reporter moved to separate main menu item, calibration hydrographs improved
- Stochastic disaggregation preserves hourly precipitation fixing 2008.1 error
- SWMM Reporter loads multiple files and saves run IDs
- Stochastic hourly disaggregation algorithm has new spiking factor
- Customizable annual storm depth histograms added to IDF output
- SWMM Reporter also supports SWMM 4 and can append to existing datasets

- previous restrictions removed for SWMM simplification of large files
- STORM supports acre-feet as storage and treatment units
- new SWMM Reporter menus support SWMM5 calibration and statistical reports
- correct error in STORM most efficient size introduced in 2007.3
- STORM multi-run facilitates constant specification
- IDF lists percentiles
- precipitation by hour of day and month matrix added to IDF statistics
- Excel STORM includes first flush parameters
- short-duration disaggregation and multi-gage decomposition write gage IDs
- paired stochastic daily disaggregation algorithm improved
- help pages added for NetSTORM output tables
- correct error: STORM multi-runs did not process metric datasets properly after the first iteration
- SWMM simplification reads/writes comment lines
- Excel STORM uses explicit metric parameter

- allow drag-drop of input file names from Windows onto text boxes
- correct errors for SWMM simplication export of unsimplified files, improve dialogs
- all daily precipitation disaggregation options now work with all rainfall formats
- Rescale/Reformat no longer reports extraneous errors when PC setting for date order differs from m/d/y
- Excel STORM uses either rain format
- Windows Vista compatibility modifications: default to user's root folder; datasheets use MSOWC 11
- SWMM simplication checks for zero-height conduits
- date formats d/m/y and y/m/d recognized
- SWMM simplication prioritizes merging manholes with unknown inverts and handles [LOSSES] and [INFLOWS] sections
- new feature Read | USHCN daily and monthly datasets
- correct error where NetSTORM module was not reading multi-gage rain files properly
- new feature Transform | SWMM5 Simplication rationalizes SWMM5 input files. Unlicensed users can only operate on small datasets
- correct error reporting storm durations in IDF output for sub-hourly datasets
- STORM uses metric or English units
- 12 minute data options in disaggregation
- value threshold to IDF analysis excludes data points and report averages (e.g. for streamflow analysis)
- improve support messages for license expiration and IDF password

- IDF event listings in tabbed columns
- max intensity and mean event duration added to monthly and annual statistics in IDF analysis
- short-duration disaggregation and rescale/reformat dialogs improved
- fix problem where time series values greater than 100 were causing program to crash
- statistical summary at end of detailed STORM output improved
- output files open at beginning, rather than end of file
- minor reformatting of IDF drought and storm statistics
- Web hyperlinks added to About dialog
- replace final storage reporting with max storage reporting in STORM, storm list in tabbed columns
- Internet release
- improve Analyze|IDF output. Was not saving results for multiple files. Add password protection for large file analysis
- improve Transform|Reformat|Cross-tab. Was not reading sub-hourly files properly
- speed-up Transform|Rescale|Pad zeroes function

- default precipitation format changed from gggg yyy mm dd hh to mm/dd/yyyy hh:mm
- DLL runs much faster and reliably on Windows XP
- new option for computing snowmelt-equivalent precipitation
- NetSTORM date data in .dbf files now more easily read in other programs
- additional summary information in STORM output including overflow duration
- Known issue: running Paired Daily Disaggregation twice in succession causes crash
- NCDC-imported data has comment line at top giving gage ID and source file name
- computational error corrected in STORM. Internal precision of constant MGTOIN was affecting storage-treatment calcs
- new option to select geometric (previously "multi-run") or arithmetic sequencing for STORM multi-scenario runs
- error fixed in Sanitary Flow and Percent Capture calculation in NetSTORM monthly summary table
- license agreement added to installation package
- improved formatting of STORM summary output
- NCDC comma-delimited precipitation files can be imported