Hysteresis Effect in the Link Flow versus Depth Relationship in SWMM 5

Subject:  Hysteresis Effect in the Link Flow versus Depth Relationship in SWMM 5

You can often get a hysteresis effect for the Flow versus Depth relationship in SWMM 5 due to the five component St. Venant equation used to simulate the flows (http://swmm5.blogspot.com/2010/12/what-are-units-for-five-st-venant-flow.html) .  A hysteresis effect is having two or more flow values for the same depth value in the link. For example, this image shows how the link 8100 has a different flow for the same depth in the rising and falling limb's of the hydrograph.  This is due to the different values for the upstream and downstream head, hydraulic radius and cross sectional area during the falling and rising hydrograph, respectively.

Flow Units In InfoSWMM may be different then the Output Link Flow Units

Note:  Flow Units In InfoSWMM may be different then the Output Link Flow Units

The flows units selected in Run Manager determines the flow units of all incoming units including DWF, Inflow Time Series and other features in pump curves and other curves.  The output unit manager determines what you see when you make a graph of the link flow.  For example, you can have dry weather inflow of CFS and output units of GPM or MGD if you so request and set the correct flags in the interface.

 

Export from WeatherUnderground using the CSV File Export Option to InfoSWMM

Note:  Export from WeatherUnderground using the CSV File Export Option to InfoSWMM

 Weather Underground is a site that provides excellent local weather information in the form of graphs, tables and csv files. You can use the data very easily in InfoSWMM by copying from Excel to a time series in InfoSWMM. Here is the rainfall for a storm event in Tampa, Florida in September 11, 2010

Step 1: Export from WeatherUnderground using the CSV File Export Option

Step 2: The data imported from the csv file to Excel and after the text to columns tool is used looks like this in Excel. The data is now ready to be imported into InfoSWMM after the time column is adjusted to fall on even 5 minute intervals. In Excel you can use the formula @ROUND((B2)/"0:05:00",0)*"0:05:00" to round all of the time values to 5 minutes. If you do not do this step then you will have problems in InfoSWMM due to the rainfall interval not being equal to the defined raingage interval.

Step 3: You will need to format the new rounded time as a time format for import into a InfoSWMM time  series.  The time series is created in the operation tab of the attribute browser.

Step 4: Open up and make a new time series in InfoSWMM.

Step 5: Copy and then paste the date, rounded time column and rainfall column into the InfoSWMM time series columns.

 Step 6:  Make a raingage in the DB Table in InfoSWMM that will use the time series you just made.  In the case of the Weather Underground data we will use inches, intensity, a rainfall interval of 5 minutes, time series and the name of the time series.  SCF should be 1 for Snow conversion and do not need to include a Filename or Station name as we are not using an external file.

Time Step Selection in InfoSWMM and SWMM5

1^st The time step you use in SWMM 5 is controlled from the top by the rainfall interval (Figure 1):

1.   All of your time steps should be less than the rainfall interval,

2.   The hydrology time step should be less than or equal to the smallest raingage rainfall interval in your network,

3.   The hydraulic time step should be less than or equal to the hydrology time step and should be based on the hydraulic needs of the your network.  Short length links, pump and weirs may require a smaller maximum hydraulic time step.

2^nd The report time step controls what you see in the graphics output of SWMM 5. If you see a large difference between that you see in the graphics output and the report text file it is because you have a large difference between the report time step and the average time step used during the simulation.

Solution: If there is a large discrepancy in the graphics and report text file then the best solution is to reduce the maximum time hydraulic time step so it is closer to the average time step and also to make the report time step closer to the Maximum time step (Figure 2).

Figure 1:  Relationship between the rainfall, hydrology and hydraulic time steps.

Figure 2:  Relationship between the minimum, average and maximum simulation time steps and the report time step.

InfoSewer Flow Attenuation Sensitivity

InfoSewer Flow Attenuation Sensitivity 

The three Run manager parameters, Maximum Number of Segments, Minimum Travel Distance and the Minimum Travel Distance in InfoSewer and H2OMAP Sewer affect the shape and flow attenuation of the flow in a link.  The effect of using the flow attenuation is to reduce the peak flow and spread out the flow compared to the No Flag option (Figure 1). 

Figure 1.  Effect of the Flow Attenuation Option in infoSewer and H2OMAP Sewer

InfoSewer Inflow Control for a PUMP

InfoSewer Inflow Control for a PUMP

You can control the pumps in InfoSewer and H2OMap Sewer by using a Pump Control which will control the pump based on:

1.       Volume

2.      Level

3.      Discharge

4.      Inflow

5.      Time

If you use a By Inflow control the pump speed of the pump is increased or decreased to make the Upstream Wet Well Level Constant (Figure 1).

Figure 1.  Inflow Control for  PUMP in InfoSewer and H2OMAP Sewer will change the Pump Speed of the pump to make the Wet Well level constant

InfoSewer Maximum Number of Segments Sensitivity

InfoSewer Maximum Number of Segments Sensitivity

The three Run manager parameters, Maximum Number of Segments, Minimum Travel Distance and the Minimum Travel Distance in InfoSewer and H2OMAP Sewer affect the shape and flow attenuation of the flow in a link.  The effect of decreasing the Minimum Travel Distance is to reduce the peak flow and spread out the flow as the number of segments increases(Figure 1).  The smaller the minimum travel distance, which has the effect of increasing the number of segments in a link up the limit of the parameter Maximum Number of segments, the smaller the peak and the more attenuation of the flow in InfoSewer.

There is three ways to control attenuation in InfoSewer: (1) use the flow attenuation option, (2) increase the Maximum Number of Segments per link and (3) decrease the Minimum travel distance.    You can also use all three parameters to make more segments per link for long links and only a few segments for short links.

Smoother Switching Between Pumps in SWMM 5 - A better simulation of a VSP?

Subject - Smoother Switching Between Pumps in SWMM 5 - A better simulation of a VSP?

An oft requested feature in SWMM 5 is the ability to better simulate a variable speed pump.   The basic feature we are trying to model is multiple pumps between two nodes, one pump curve for all of the pumps and the ability to turn on and turn off the pumps based on either the head or depth at a Wet Well (Figure 1).  You can turn on or off the pumps Pump1, Pump2 and Pump3 based on the depth at the Wet Well but this feature is stepwise linear and usually uses three pump curves.  A better way to simulate this feature is to use the SWMM 5 Real Time Rules (RTC) to simulate the Pump setting based on a control curve.  

The Pump flow at any time step is the Pump Flow estimated from the Pump Curve (Figure 2) * The Pump Setting (Figure 3)

Each of the three pumps has a different Control Curve (Figure's 4, 5 and 6, respectively) which turns on or turns off the Pump based on a range of Wet Well Depths.  The overall effect is that the total flow summing all three pumps together is smoother (Figure 7 and Figure 8) and the user can simulate different pump speeds based on the same pump curve depending on which pump is currently on.

Figure 1.   Example RTC Rules and VSP Pumps in a SWMM 5 model.

Figure 2.  The Pump Curve Used for all 3 Pumps

  

Figure 3.  The Pump Setting for all Three Pumps

Figure 4.   Pump Control Curve for Pump 1.  The Pump has a Setting of ¼ between 0.5 and 3 feet at the node Wet Well and zero otherwise.

Figure 5.   Pump Control Curve for Pump 2.  The Pump has a Setting of 1/2 between 3 and 5 feet at the node Wet Well and zero otherwise.

Figure 6.   Pump Control Curve for Pump 3.  The Pump has a Setting of 1 above 5 feet at the node Wet Well and zero otherwise.

Figure 7.  The Flow in all 3 Pumps.

  

Figure 8.  The total flow from all three Pumps to the downstream node.

Leaping Weir Example in SWMM 5 and InfoSWMM, Alternative

Leaping Weir Example in SWMM 5 and InfoSWMM, Alternative

This is an example SWMM 5 model that can be imported into InfoSWMM or H2OMap SWMM using the Exchange/Import Command.   The low flow falls over the berm of the leaping weir into a rectangular open channel but the the "falls" is governed by an OULET Depth/Discharge Type in SWMM 5.  The flow increases in the OUTLET until a depth of 1 feet is reached where the weir starts to operate.  The OUTLET increases in flow from zero to 1 feet but still flows at a reduced rate when the weir starts to operate.  The weir stops flowing when the depth goes below 1 foot on the berm.

SWMM 5 Input File Link
Background Image

Leaping Weir With Low Flow Depth/Discharge OUTLET

H2OMAP Sewer and InfoSewer DB Queries to find Loading Manholes

Subject:   H2OMAP Sewer and InfoSewer DB Queries to find Loading Manholes

This Database Query (DB) will find all loading Manholes with a Load1 and a Load2 greater than 0.  InfoSewer has up to ten possible loads in a Manhole.  You can use the DB Query (Figure 1) to create a Query Report to show all of the Manholes with a non zero loading for both Load1 and Load2.  New Queries can be made to show any combination of the ten Manhole Loadings either by altering the DB Query or creating a new DB Query.

Figure 1. DB Query to find Manholes with Load1 and Load2 greater than 0.0

Figure 2.  Query Report for the DB Query

How to Use Group Delete to Make A Smaller Model in SWMM 5

How to Use Group Delete to Make A Smaller Model in SWMM 5

Use Select All, Group Delete and the Tag Feature

1.        Label or Tag all of your Subs as Out and make the one you really want to simulate called Domain
2.       Select the whole model using the Select All command
3.       Delete all Subs with Out and only the Domain will remain
4. 
   

Calibration data in H2OMAP SWMM, InfoSWMM and SWMM 5 does NOT have to be at the same time step

Calibration data in H2OMAP SWMM, InfoSWMM and SWMM 5 does NOT have to be at the same time step pic.twitter.com/S1leombWqs
— RDickinson (@RDickinson) July 1, 2013

Canada Day and a SWMM 5 Model with Flow Dividers

Canada Day and a SWMM 5 Model with Flow Dividers

Happy Canada Day,  A SWMM 5 Model with Canada Day as the WaterMark along with an Interesting SWMM 5 Model with Flow Dividers - it only works in Kinematic Wave Mode

Flow Divider Inp File
Canada Day Image

Check out my animated twitter snapshot

Check out my animated twitter snapshot. https://t.co/G5L0jwPAJ1
— RDickinson (@RDickinson) June 26, 2013

Cities Are a New Kind of Complex System: Part Social Reactor, Part Network

Cities Are a New Kind of Complex System: Part Social Reactor, Part Network

Scientists have derived a series of mathematical formulas that describe how cities' properties vary in relation to their population size, and then posits a novel unified, quantitative ... full story  from Science Daily http://www.sciencedaily.com/releases/2013/06/130620142925.htm

Two Pass InfoSewer Solution

Two Pass InfoSewer Solution

🔰The Two-Pass InfoSewer Solution method refines the estimation of flow within sewer networks by employing a dual-stage analysis. Initially, in the first pass, the system calculates the loads at each manhole and subsequently deduces the flow in the connecting links. This initial flow estimation is utilized to determine the preliminary depth-to-diameter ratio (d/D), the values of which you are presently mapping.

🔰Subsequently, the second pass of the solution process takes place. This stage is critical as it accounts for complex hydraulic phenomena, including backwater effects, surcharge conditions, and pressurized flow. It is during this phase that the depth-to-diameter ratio is adjusted, often resulting in an increased d/D value compared to the initial pass. This adjusted d/D is depicted in the Hydraulic Grade Line (HGL) plot.

🔰Utilizing the adjusted d/D from the second pass provides a more accurate indication of pipeline capacity and performance, particularly identifying pipes operating at or above 75% fullness. This metric is essential for effective sewer system management, offering a clearer insight into the potential for overflow and the need for infrastructural intervention.

Adjusted d/D is a better way of finding those pipes that are more than 0.75 full

How to Locate Parallel Pipes in H2OMAP SWMM

How to Locate Parallel Pipes in H2OMAP SWMM

You can use the command *Utility/Network Review Fix/Locate Parallel Pipe/Show as Domain *or as list of ID's

Utility/Network Review Fix/Locate Parallel Pipe/Show as Domain 

Massive Flooding In Alberta Canada Forces 75,000 To Flee

By Rebecca Leber posted from Climate Progress on Jun 22, 2013 at 3:00 pm

Alberta, Canada. Credit: AP

Parts of Alberta, Canada were hit by extreme flooding the size of New York State on Friday, forcing 75,000 to evacuatetheir homes. Hit by heavy rain, people have abandoned their cars and low-lying residences in flooded waters Mayor Naheed Nenshi described as “an ocean at the moment.”

Across the world, cities in Germany have also been wrecked by flooding — one estimate puts the damage as high as $7.7 billion. Climate science explains that global warming leads to a 5 to 10 percent increase in rainfall, and subsequently leads to a higher risk of flooding.

As Climate Central notes in its reporting on the Calgary floods: “A study published in the journalNature Climate Change on June 9 found that flood frequency as well as the number of people at risk of inundation from flood events are both likely to increase as the world continues to warm.”

Heavy precipitation extremes, which sometimes result in river flooding, have been increasing in much of the U.S. east of the Mississippi River. Credit: Climate Central.

Alberta is home to controversial tar sands development, where the city of Calgary happens to be a source of climate denier arguments: The Calgary Herald, an influential paper in western Canada, has spouted climate denier points on its editorial page. The University of Calgary, meanwhile, was once paid to distribute resources opposing climate change science.

How to Find Duplicate Links in InfoSWMM

1. Make a table of all  From Nodes for all of the links using Conduit Information,
2. Made an output DBF table using the summary command of the Open Attribute Table of Arc Map
3. Joined the output DBF table to the Junction layer
4. Labeled all Nodes that had more than one outgoing link
5. You can see on the screen the possible duplicate links and decide which are valid and which are not allowed

How to Find Duplicate Links in InfoSWMM pic.twitter.com/BUJvhIkGnd
— RDickinson (@RDickinson) June 23, 2013

The meaning of Geom1, Geom2, Geom3 and Geom4 in InfoSWMM and H2OMap SWMM

The meaning of Geom1, Geom2, Geom3 and Geom4 in InfoSWMM and H2OMap SWMM pic.twitter.com/ChdI3IQq6t
— RDickinson (@RDickinson) June 21, 2013

All of the rivers in the USA

Photo: mishagl: All of the rivers - Perhaps inspired by All Streets, Ben Fry’s map of all the streets in the... http://t.co/4xO9KdIdtP
— RDickinson (@RDickinson) June 20, 2013

Liu Yang introduces delegates to GIS-Based design solution InfoSewer at a packed @innovyze UK User Group

Liu Yang introduces delegates to GIS-Based design solution InfoSewer at a packed @innovyze UK User Group http://t.co/wD4Y11Wnkx
— Innovyze (@Innovyze) June 19, 2013

H2S Modeling in InfoSewer

H2S Modeling in InfoSewer, the basic model needs pic.twitter.com/OyfeMekrUU
— RDickinson (@RDickinson) June 17, 2013

How to Use Excel to Make Random X, Y Coordinates in SWMM 5

Node	X	Y	Rand X	Rand Y
A	2465753425	-1799501868	1114137518	-1734364827
B	1220423412	-915317559.2	959332294.5	-427183555.6
C	1207970112	-2970112080	939805860	-417442286.9
D	-485678704.9	2970112080	-172000249.5	1835904922
E	-2789539228	1388542964	-2050647732	326604825.1
F	-4221668742	-130759651.3	-3537896272	-59872442.99

If you have a SWMM 5 file without any X, Y  coordinates you can assume an X and a Y and then use Excel to make each pair random by using the RAND() function.  You at least will see each of the nodes on the screen with associated links.

How to Estimate the Needed Time Step for your Model using DB Tools in InfoSWMM

How to Estimate the Needed Time Step for your Model using DB Tools in InfoSWMM pic.twitter.com/zpoZyNPQaq

— RDickinson (@RDickinson) June 14, 2013

How to Make Custom Labels in InfoSWMM and InfoSewer

How to Make Custom Labels in InfoSWMM and InfoSewer pic.twitter.com/ikx0dxsl01

— RDickinson (@RDickinson) June 14, 2013

How to simulate a Quasi Steady Run in InfoSWMM, H2OMap SWMM or SWMM 5

How to simulate a Quasi Steady Run in InfoSWMM, H2OMap SWMM or SWMM 5 pic.twitter.com/4un4P19HFo
— RDickinson (@RDickinson) June 14, 2013

Steps in Merging Two InfoSWMM Models without any Scenarios

Steps in Merging Two InfoSWMM Models without any Scenariostwitpic.com/cwik9h

— RDickinson (@RDickinson) June 10, 2013

Wikipedia Traffic for the SWMM versus EPANET Articles

Subject:  Wikipedia Traffic for the SWMM versus EPANET Articles

Wikipedia has one article for EPANET and three articles for SWMM 5 (two are redirected to the Stormwater Management Model Main Article).  The statistics for the last three years (data before 2007 is unavailable) show an average of 28 visitors per day to SWMM and 16 per day to EPANET).  The search name has switched from the word SWMM to Stormwater Management Model starting in 2009.

Losses from a Subcatchment in SWMM 5 are composed of Evaporation + Infiltration = Total Losses

Losses from a Subcatchment in SWMM 5 are composed of Evaporation + Infiltration = Total Lossestwitpic.com/cv8oc5
— RDickinson (@RDickinson) June 4, 2013

Applicazione di tecnologie BMP ai sistemi di drenaggio urbano , It is about SWMM 5 and LID's

A good thesis from Italy on modelling BMP's and LID's in an Urban Environment
Applicazione di tecnologie BMP ai sistemi di drenaggio urbano

Figure 1,  Applicazione di tecnologie BMP