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Showing posts from September, 2012

### How to Use Trace Upstream, Domain Manager and Facility Manager in InfoSewer to Find the CE

Subject:   How to Use Trace Upstream, Domain Manager and Facility Manager in InfoSewer to Find the CE

How to Use Trace Upstream, Domain Manager and Facility Manager in InfoSewer to Find the CEby dickinsonreSubject:   How to Use Trace Upstream, Domain Manager and Facility Manager in InfoSewer to Find the CE
InfoSewer does not have table of node continuity errors only an overall continuity error balance.  If you have a continuity error then you can use the process of divide and conquer to find the continuity error.  Start at the Outlets and using the Trace Upstream command, Domain Manager and Facility Manager take out whole sections of the network until you isolate the section of the network with the continuity error.    Here are the steps you can take:
Step 1.             Use Trace Upstream Network to find the and place in a Domain the Upstream Network (Figure 1). Step 2.                          Once the upstream domain is created use the Domain Manager to add in any extra links without n…

### InfoSWMM (d/D v. Surcharge d/D)

Subject:   InfoSWMM (d/D v. Surcharge d/D)

What is the difference between the output variables d/D and Surcharge d/D in InfoSWMM and H2OMap SWMM

The d/D is calculated as link capacity based on the midpoint depth of water in the link or Link depth/ Link Maximum Depth
Since the depth in the link is restricted to the Maximum Depth the d/D value is always between 0 and 1
The Surcharged d/D is calculated from the end node depths at each end of the link
The two node depths are averaged and the value of Surcharge d/D is the Average Node Depth / Link Maximum Depth,
The value of Surcharge d/D varies from 0 to a large number depending on the maximum depths of the nodes and the possible surcharge depth of the nodes
The value of d/D is based on the middle of the link and the value of Surcharge d/D is based on the average of the node depths at the end of the link.  They may be and often are different.   However, if you have a Surcharge d/D greater than 1 it will indicate at least…

### Reasons A Pump H-Q Curve may be Different than the Design Curve

Subject:   Reasons A Pump H-Q Curve may be Different than the Design Curve

From Allan R. Budris and Water World

Actual system H-Q curve not known: The actual current system H-Q curve may be different than the original system design. Once a plant is commissioned and the plant is put in service, the system head begins to change. In the short term, levels change in the tanks and wells, valves open and close, and filter screens become clogged. As maintenance occurs, pipe schedules are changed, equipment is changed and new equipment is added into the system. In the long term, equipment loses efficiency, scale forms on the internal pipe walls and the plant undergoes expansion and contraction. Even when new, the original calculated system curve may differ from the actual system performance due to the assumptions used in the calculation, such as 10 year old pipe. Any pump change should, therefore, start with the development (confirmation) of the true current pumping system “Head-Capacity” curve,…

### Storage Nodes in InfoSWMM and H2OMAP SWMM

Subject:   Storage Nodes in InfoSWMM and H2OMAP SWMM

Figure 1 shows how to use the various constants, coefficients and exponents in the Storage or Wet Well data of H2OMAP SWMM.     If you have a Wet Well or Storage Diameter you should convert the Wet Well diameters into an Area with the units of either square feet or square meters.  The computed area will then be a constant or coefficient in the Attribute Browser.  You would only use the exponent or a table of depth and area if the Wet Well area varies with depth.