The Pump summary table of SWMM5.0.022 and the Percent Time off Columns

Subject:  The Pump summary table of SWMM5.0.022 and the Percent Time off Columns

The pump summary table at the end of the SWMM 5 report file has two columns for the time off the pump curve BUT the two columns are only informative if the pump is a type 4pump.  If the pump type is 1, 2 or 3 then the low column is always 0 and when the volume, depth or head is either below the lowest point in the point curve or above the highest point in the pump curve the pump summary table lists the time off either low or high in the High column.

xMin is  the 1^st point in the pump curve for either volume, depth, head or depth, respectively for pump1, pump2, pump3 and pump4 type pumps

xMax is the last point in the pump curve for either volume, depth, head or depth, respectively for pump1, pump2, pump3 and pump4 type pumps

Use the SWMM 5 Scatter Graph to show the Pump Curve used during the Simulation

Subject:  Use the SWMM 5 Scatter Graph to show the Pump Curve used during the Simulation

You can use a scatter graph to show the relationship between the pump during the simulation and the Storage Depth.   If the pump is on the curve based on the pump summary table then the scatter graph should  look like the pump curve.  The pump summary table in the  SWMM 5 RPT also shows you the time off the pump curve low and high. 

The Importance of Viewing Results at the Proper Time Scale in SWMM5 and InfoSWMM Models

Subject:   The Importance of Viewing Results at the Proper Time Scale

In SWMM 5 when you are simulating rapidly changing flow – such as pump flows – it is important to  remember that you are only seeing the results of the simulation at your selected report time step.  Here is an example model with the same number of pump starts for all three simulations (318), the same  average time step during the simulation (10 seconds) but different report time steps.  The conception of the pump starts is totally different visually depending on the selected report time steps.  You should always compare the starts using the pump graphs and the pump summary table.    The percent utilized and the number of pump start ups tells you  the mean pump start length or in this case 153 seconds or 45.1 percent of 30 hours divided by 318 pump starts.

Pump Volume per Pump Event in SWMM 5

Subject: Pump Volume per Pump Event in SWMM 5

You can calculate the volume per startup event by using the Pump Summary Table in SWMM 5 and copying a few columns to Excel.   

1.   Go to the Pump Summary

2.   Copy Pump Name, Total Volume and Pump Startups to Excel

3.   Divide to get Pump Volume per Event

You will now have the average volume per event.

Pump	Total	Total Volume	Pump
Name	Volume (ML)	L Per Event	Startups
PUMP-11	0.006082	202.73	30
PUMP-13	0.005539	184.63	30
PUMP-15	0.006241	208.03	30
PUMP-17	0.0064	213.33	30
PUMP-19	0.005405	180.17	30
PUMP-21	0.006199	206.63	30

Inc.

Comparison of the H2OMAP SWMM5 Hazen Williams Force Main Solution to a HW Solution

Note:  Comparison of the H2OMAP SWMM Hazen Williams Force Main Solution to a HW Solution

In this example, we compare the force main head loss in four links in H20Map SWMM to the head loss in a steady state HazenWilliams solution for the same length pipe, diameter and flow (Figure 1).  The H2OMap SWMM model has a large constant dry weather inflow at the wet wells which floods the wet well and causes a constant pump flow to the force main (Figure 2).  TheHW calculator is located here http://www.engineeringtoolbox.com/william-hazens-equation-d_645.html and a comparison forHW head loss in PSI for 5000 feet long, 3 inch diameter pipes with HW Coefficients of 130, 120, 110 and 100, respectively, is shown in Table 1.   The SWMM 5 equation loss (PSI Diff) and the PSI loss from the HW calculator are very close for all four links. 

Table 1.  Steady State comparison between HW Calculator and H2OMAP SWMM/SWMM 5 Force Main calculations.

HW	SWMM5	SWMM5	SWMM5 Loss	Loss
Coefficient	Psi UP	PSI Dn	PSI Diff	PSI HW Calculator
130	84.563	44.88	39.683	39.82
120	88.772	43.765	45.007	45.16
110	91.798	41.426	50.372	50.54
100	95.354	38.727	56.627	56.82

Figure 1.   H2OMAP SWMM Wet Well, Pump, Force Main and Gravity Main Network.

Figure 2.  Constant Pump Flows

Steady State Flow Analysis in InfoSWMM using a Ramp DWF

Subject:  Steady State Flow Analysis in InfoSWMM using a Ramp DWF

This can be easily created using a few steps in InfoSWMM. 

Step 1:  Using Scenario Explorer make a cloned Child Scenario and a cloned DWF Set which will be later modified.

Step 2:  Using DB Manager and the BlockEdit tool and increase the mean DWF by a factor of 10, 100 or 1000 to drown out all Wet Wells and cause the pumps to turn on and stay turned on during the simulation in the newly created DWF Set.

Step 3.  Run the batch manager and create two output files – Normal and Steady State for comparison.

Step 4.  You can now compare the two scenario's using Output Manager and the Compare Graph tool.  The Ramped Model should have constant flows in both links and pumps.  It was not necessary to change any of the patterns.

Step 5.  The model is still  in balance – the excess DWF Inflow ends up as flooded flow and is listed as Internal Outflow.

SWMM 5 Clocktime RTC Rules for Pumps, Weirs and Orifices

Subject:  SWMM 5 Clocktime RTC Rules for Pumps, Weirs and Orifices

You can use the Control or RTC rules in SWMM 5 to adjust the settings of the weirs, pumps and orifices based on the clock time each day of your simulation.  Here is an example that will adjust orifice height every ½ hour for 7 orifices at one time using two sets of rules.

RULE R1a 

; Half hour setting

IF SIMULATION CLOCKTIME = 0:30:00 

OR SIMULATION CLOCKTIME = 1:30:00  

OR SIMULATION CLOCKTIME = 2:30:00 

OR SIMULATION CLOCKTIME = 3:30:00 

OR SIMULATION CLOCKTIME = 4:30:00 

OR SIMULATION CLOCKTIME = 5:30:00 

OR SIMULATION CLOCKTIME = 6:30:00 

OR SIMULATION CLOCKTIME = 7:30:00 

OR SIMULATION CLOCKTIME = 8:30:00 

OR SIMULATION CLOCKTIME = 9:30:00 

OR SIMULATION CLOCKTIME = 10:30:00

OR SIMULATION CLOCKTIME = 11:30:00

OR SIMULATION CLOCKTIME = 12:30:00 

OR SIMULATION CLOCKTIME = 13:30:00  

OR SIMULATION CLOCKTIME = 14:30:00 

OR SIMULATION CLOCKTIME = 15:30:00 

OR SIMULATION CLOCKTIME = 16:30:00  

OR SIMULATION CLOCKTIME = 17:30:00 

OR SIMULATION CLOCKTIME = 18:30:00 

OR SIMULATION CLOCKTIME = 19:30:00 

OR SIMULATION CLOCKTIME = 20:30:00 

OR SIMULATION CLOCKTIME = 21:30:00 

OR SIMULATION CLOCKTIME = 22:30:00

OR SIMULATION CLOCKTIME = 23:30:00

THEN ORIFICE R1 SETTING = 0.90

AND  ORIFICE R2 SETTING = 0.90

AND  ORIFICE R3 SETTING = 0.90

AND  ORIFICE R4 SETTING = 0.90

AND  ORIFICE R5 SETTING = 0.90

AND  ORIFICE R6 SETTING = 0.90

AND  ORIFICE R7 SETTING = 0.90

RULE R1b

; hour setting

IF SIMULATION CLOCKTIME = 0:00:00

OR SIMULATION CLOCKTIME = 1:00:00

OR SIMULATION CLOCKTIME = 2:00:00

OR SIMULATION CLOCKTIME = 3:00:00

OR SIMULATION CLOCKTIME = 4:00:00

OR SIMULATION CLOCKTIME = 5:00:00

OR SIMULATION CLOCKTIME = 6:00:00

OR SIMULATION CLOCKTIME = 7:00:00

OR SIMULATION CLOCKTIME = 8:00:00

OR SIMULATION CLOCKTIME = 9:00:00

OR SIMULATION CLOCKTIME = 10:00:00

OR SIMULATION CLOCKTIME = 11:00:00

OR SIMULATION CLOCKTIME = 12:00:00 

OR SIMULATION CLOCKTIME = 13:00:00

OR SIMULATION CLOCKTIME = 14:00:00 

OR SIMULATION CLOCKTIME = 15:00:00

OR SIMULATION CLOCKTIME = 16:00:00

OR SIMULATION CLOCKTIME = 17:00:00

OR SIMULATION CLOCKTIME = 18:00:00 

OR SIMULATION CLOCKTIME = 19:00:00 

OR SIMULATION CLOCKTIME = 20:00:00 

OR SIMULATION CLOCKTIME = 21:00:00 

OR SIMULATION CLOCKTIME = 22:00:00 

OR SIMULATION CLOCKTIME = 23:00:00

THEN ORIFICE R1 SETTING = 0.5

AND  ORIFICE R2 SETTING = 0.5

AND  ORIFICE R3 SETTING = 0.5

AND  ORIFICE R4 SETTING = 0.5

AND  ORIFICE R5 SETTING = 0.5

AND  ORIFICE R6 SETTING = 0.5

AND  ORIFICE R7 SETTING = 0.5

How to see the effect of the Pump Setting in the RTC Rules of InfoSWMM and H20MAP SWMM

Subject:  How to see the effect of the Pump Setting in the RTC Rules of InfoSWMM and H20MAP SWMM

Step 1.   Pump Startup and Shutoff Depth

Depths to turn the Pump On and turn the Pump Off.  In this example, the pump will be off when the Wet Well Depth is less than 2 feet, the Pump will be off between a Wet Well Depth between 2 and 5.75 feet if the Pump is currently Off and the Pump will be On between a Wet Well Depth between 5.75 and 2 feet.

Step 2.   RTC Rule for the Pump Setting when the Wet Well Depth is less than 6.25 feet.  We need to add the AND statement so that the setting is only reset when the Pump is On.   You do not want the pump setting to be reset when the pump should be off.

Result 1:  The Pump Speed Ratio tells you the Pump Setting

Result 2:  RTC Control Rules in the RPT File if you click on Show Control Actions

Result 3:   The depth at the Wet Well and the Flow in the Pump

Result 4:  A mixed graph of the Wet Well Depth and Pump Flow shows the effect of the RTC.

Result 5:  The RTC Rule can also been seen flow to the Pump Curve.