Showing posts from August, 2013

The Link Time Step in SWMM 5, InfoSWMM and H2OMap SWMM

Introduction:  This set of blogs uses the 1000 year rainfall/runoff/hydraulics model that you can download at to show the inner workings of SWMM 5 and by extension InfoSWMM and H2oMap SWMM using a QA/QC version of SWMM 5 with extended graphics.   I always hope that seeing the inner workings of a SWMM 5 feature helps to understand the code, sensitivity and importance of a parameter.   It also helps show sometimes when a parameter is not important.  

Discussion:  Here we look at the link time step for a 100 year simulation.   If you use the Variable Time Step in SWMM5 with the CFL Adjustment factor the program will compute the needed link time step at each simulation time step based on the last time steps depth, velocity and width.  The link time step is
Link Time Step = Adjustment Factor * CFL Explicit Time Step for the Controlling Link
The time step is larger for low flows and decreases as the flow in t…

IO9- What really causes that amazing "after the rain" smell?

From the great blog and website, IO9, an explanation about the why it smells so nice after a rainfall  What really causes that amazing "after the rain" smell?
After a rainstorm, especially a rain storm that breaks a long dry spell, the world smells different. What causes that strange, clean, earthy smell? A few things that aren't so clean. One of the benefits of living in California is the extraordinary smell you get after the first rain of the fall. Generally it's in October or November, in a climate where warm summer rainstorms are unheard of and nothing has seen moisture in half a year. Right after the rain there's an intense smell that you have to huff while you can. It's incredibly strong. But we're not the only place that gets such a smell. People everywhere notice it, and scientists have a few theories as to what causes it. Some of the smell, especially the parts that people identify as "clean," probably come from ozone. Oxygen atoms usual…

What Node and Link Invert Elevations Does SWMM 5 Use?

Note:What Node and  Link Invert Elevations Does SWMM 5 Use?

SWMM 5 uses the following Node information from the user: ·Node Invert Elevation,
·The Node Rim Elevation which is the Node Invert Elevation + the Maximum node depth
·The Ponded Area when the Ponded  Area option is used
·The Surcharge Depth above the Node Rim Elevation

SWMM 5 uses the following link information from the user: ·The Link Upstream Offset Depth or Offset Elevation and
·The Link Downstream Offset Depth or Offset Elevation
·The Link Maximum Depth or Diameter

SWMM 5 calculates the following information internally: ·The Pipe Crown Elevation at the upstream and downstream link nodes.  The Pipe Crown is the Pipe Diameter + Link Offsets
·The Node Highest Pipe Crown Elevation,  the new rim elevation will be used in the program
·The Surcharge Depth above the Rim Elevation if the Node has a Surcharge Pressure Depth at the Node during the simulation,
oIf the Surcharge Depth is 0 then the program will either lose the flooded water or s…

InfoSWMM Error Messages and Arc Map Invalid Characters

InfoSWMM Error Messages and Arc Map Invalid Characters
A few other invalid characters are shown here in addition to the space character.  The Arc Map Link is if you want more information. 000354 : The name contains invalid characters Resource Center Description Any database may have naming restrictions for table and field names. For instance, a table in a file geodatabase cannot include a space. Solution Alter the name to remove any invalid characters. For instance, consider using an underscore (_) in place of a space. Geoprocessing methods exist that allow you to validate table and field names. Consider using either the ValidateTableName or ValidateFieldName function to ensure your name is valid. Learn more about validating table and field names.
·Any field names start with an invalid character (`~@#$%^&*()-+=|\\,<>?/{}.!'[]:;_0123456789) ·Any field names contain an invalid character (`~@#$%^&*()-+=|\\,<>?/{}.!…

UK Environment Agency Study Confirms Leading Capabilities of InfoWorks ICM

Press Room | Products | News | Events | The Company UK Environment Agency Study Confirms Leading Capabilities of InfoWorks ICM Innovyze Smart Integrated Catchment Solution Excels in Examination of Two-Dimensional Modeling Solutions Broomfield, Colorado, USA, August 20, 2013 — Innovyze, a leading global innovator of business analytics software and technologies for smart wet infrastructure, today announced the excellent performance of its industry-leading InfoWorks ICM solution, as reported in the UK Environment Agency’s recent “Benchmarking the latest generation of 2D hydraulic flood modelling packages” publications catalogue (August 14, 2013).InfoWorks ICM successfully completed all tests and was singled out as a solution that fully supports the ability to link two-dimensional flood models to one-dimensional elements. The validation by this leading UK agency further highlights InfoWorks ICM as a market leader in the high-performance modeling of two-dimensional overland flow.

The Environme…

Vacuum Sewers

Vacuum Sewers Compiled by:Beat Stauffer (seecon international gmbh) Source:
Executive Summary Vacuum sewerage systems consist of a vacuum station, where the vacuum is generated, the vacuum pipeline system, collection chambers with collection tanks and interface valve units. In contrast to conventional gravity sewerage systems with intermediate pumping stations, the permanent pressure within the vacuum system is maintained below atmospheric pressure. Moreover, vacuum technology reduces water consumption considerably, enabling flexible installations regardless of topography and water availability. In addition, it allows for the use of alternative wastewater handling (blackwater and greywater separation). InOutBlackwaterFaecal SludgeGreywater,BrownwaterUrine or YellowwaterFaeces,ExcretaEnergy Blackwater,