Fifty Years of Watershed Modeling – Past, Present and Future

Fifty Years of Watershed Modeling –

Past, Present and Future

September 24-26, 2012
Boulder, Colorado

On behalf of Engineering Conferences International and the conference chairs, Anthony S. Donigian, Jr. (AQUA TERRA Consultants), andRichard Field (US Environmental Protection Agency/ORD [retired], Michael J. Baker Jr., Inc.), it is my pleasure to extend this invitation to you to participate in Fifty Years of Watershed Modeling – Past, Present and Future to be held September 24-26, 2012 at NCAR (National Center for Atmospheric Research – Center Green Campus) in Boulder, Colorado.

Continuous Simulation using SWMM 5 LID and Groundwater Features in a Linked 1D/2D Network using InfoSWMM 2D for a 50 Year Period

has been accepted for Poster Presentation at the forthcoming conference Fifty Years of Watershed Modeling: Past, Present and Future to be held September 24-26, 2012 at National Center for Atmospheric Research (NCAR – Center Green Campus) in Boulder, Colorado.

Huff Distribution SWMM 5 Model

Huff Distribution SWMM 5 Model by dickinsonre via Blogger http://www.swmm5.net/2013/08/huff-distribution-swmm-5-model.html

A SWMM 5 Model made from the Art of Jack Yerka

Subject:   A SWMM 5 Model made from the Art of Jack Yerka

A SWMM 5 Model made from the Art of Jack Yerka by dickinsonre Subject:   A SWMM 5 Model made from the Art of Jack Yerka The attached example SWMM 5 model has small rectangular conduits with a constant inflow based on a background image from Jack Yerka. via Blogger http://www.swmm5.net/2013/08/a-swmm-5-model-made-from-art-of-jack.htm

Rules for NRSCS Unit Hydrographs in InfoSWMM

Subject:  Rules for NRSCS Unit Hydrographs in InfoSWMM

Rules for NRSCS Unit Hydrographs in InfoSWMM and H2OMap SWMM by dickinsonre Subject:  Rules for NRSCS Unit Hydrographs in InfoSWMM and H2OMap SWMM Rules or Guidelines for NRSCS Unit Hydrographs if used as the Hydrology Option in InfoSWMM and H2OMAP SWMM: 1.       The Unit Hydrograph CN comes from the Subcatchment Table and the NRCS_CN Column 2.      Time of Concentration is from the TC column in the Subcatchment Table 3.      The Infiltration Model should be from the CN infiltration Model Column in the Subcatchment Database Table 4.      The CN in the Soil Database Table should be the same as the CN in the Subcatchment Database Table 5.      If the Depression Storage is zero in the Subcatchment Database Table then the Initial Abstraction in inches will be calculated as 0.2*(1000/CN-10) internally in the engine 6.      Initial Abstraction or IA in US Units =  0.2*(1000/CN-10) in American Units via Blogger http://www.swmm5.net/2013/08/rules-for-nrscs-unit-hydrographs-in.html

Low Impact Development Options in H2OMAP SWMM and InfoSWMM

Subject:  Low Impact Development Options in H2OMAP SWMM and InfoSWMM

Low Impact Development Options in H2OMAP SWMM and InfoSWMM by dickinsonre Subject:  Low Impact Development Options in H2OMAP SWMM and InfoSWMM The five options are: 1.       Rain Barrel 2.      Bio Retention Cell 3.      Infiltration Trench 4.      Vegetative Swale 5.      Porous Pavement  and be entered as controls in the Hydrology Section of the Operations Browser of H2OMAP SWMM or InfoSWMM (Figure 1) Figure 1.  The Attribute Browser Operation Tab allows you to enter LID Controls for your LID Modeling. via Blogger http://www.swmm5.net/2013/08/low-impact-development-options-in.html

How to Make a SWMM 5 Interface File from InfoSWMM

Subject:  How to Make a SWMM 5 Interface File from InfoSWMM

 The steps are easy:

1.       Make all Links Inactive by using the Facility Manager

2.      Save the flows to the OUTFLOWS file of InfoSWMM

3.      The Outlet Node of Each Subcatchment will be save to the Text File

4.      Use the Created OUTFLOWS file as the INFLOWS file in SWMM5

How is the Orifice Setting Used in SWMM 5 RTC Rules?

Subject:  How is the Orifice Setting Used in SWMM 5 RTC Rules?

How is the Orifice Setting Used in SWMM 5 RTC Rules? by dickinsonre Subject:  How is the Orifice Setting Used in SWMM 5 RTC Rules? The Real Time Control Rule for Orifice Setting can be a function of a Setting constant, Setting from a Curve, Setting from a PID controller and a Setting from a Time Series (Figure 1).    The Setting affects the Full Depth of the Orifice at each time step.  The setting which ranges from 0 to 1 can either completely close or open theorifice (Figure 2).   You will have to use the equivalent in ICM or else the settings derived from the SWMM 5 time series need to be multiplied by the orifice depth to have the same effect in ICM that it had in SWMM 5.    Figure 1.  The Possibilities for defining the Setting of an Orifice in SWMM 5 from a H2OMAP SWMM RTC dialog.    Figure 2.  The Setting affects the Full Depth of the Orifice at each time step.  The setting which ranges from 0 to 1 can either completely close or open the orifice. via Blogger http://www.swmm5.net/2013/08/how-is-orifice-setting-used-in-swmm-5.htm

How to Use the H2OMAP SWMM Calibrator for RTK Calibration

Subject:  How to Use the H2OMAP SWMM Calibrator for RTK Calibration

Step 1.   Initial Guess of the RTK data as the start of the Messy Genetic Algorithm process

Step 2. Use Min and Max Bounds of 50 and 150 Respectively and Apply the Solution at each iteration

Step 3. Check the Comparison Graph and Correlation Coefficient at Each Step

Step 4.  It should take just a few iterations if you have a good estimate of the initial RTK parameters

Step 5. Final Values with a Rsquare of 0.96 between Observed and Simulated

 

How Does a TYPE3 Variable Speed Pump Work in SWMM 5?

Subject:   How Does a TYPE3 Variable Speed Pump Work in SWMM 5?

In a SWMM 5 Type3 pump the flow is a function of the head difference between the downstream node head and the upstream node head (Figure 2) but the pump rules can be overwritten by a RTC Rule as in the attached example.   The RTC Controls in the example change the pump setting as a function of the depth in the Wet Well.  There is one pump between the Wet Well and Force Main but the Pump Setting varies from the RTC rules based on the depth in the Wet Well (Figure 1). As you can see in the composite Figure 2, the setting varies from 0, 1, 2 and 3 during the course of the simulation.

Figure 1.  How a Pump Flow is Calculated in SWMM 5.

Figure 2   RTC Rules and Schematic of a TYPE3 Pump in SWMM 5 with Force Mains Added along with three depth settings for a Variable Speed Pump or VSP.

How Does a TYPE2 Pump Work in SWMM 5?

How Does a TYPE2 Pump Work in SWMM 5?

Subject:   How Does a TYPE2 Pump Work in SWMM 5?

A SWMM 5 Type2 pump flow is a function of the depth at the upstream node (Figure 1) but the pump rules can be overwritten by a RTC Rule as in the attached example in which the pump is only turned on then the flow in the upstream link 8040 is greater than 25 cfs.

Figure 1.   RTC Rules and Schematic of a TYPE2 Pump in SWMM 5.

What are the Types of Force Mains (FM) in SWMM 5?

Subject:   What are the Types of Force Mains (FM) in SWMM 5?

What are the Types of Force Mains (FM) in SWMM 5? by dickinsonre Subject:   What are the Types of Force Mains (FM) in SWMM 5? There are five ways to model a force main in SWMM 5 for the combination of full and partial flow in the force main (Figure 1): 1.       Full Flow using Darcy-Weisbach for the friction loss 2.      Full Flow using Hazen-Williams for the friction loss 3.      Full Flow using Manning's n for the friction loss 4.      Partial Flow uses Manning's n for the friction loss for Force Main Equation options If you use Darcy-Weisbach or Hazen-Williams then an equivalent Manning's n for a force main that results in the same normal flow value for a force main flowing full under fully turbulent conditions is calculated internally in SWMM 5 in forcemain.c ·         Equivalent n for H-W is 1.067 / Hazen-Williams Coefficient  * (Full Depth / Bed Slope) ^ 0.04  ·         Equivalent n for D-W is (Darcy-Weisbach friction factor/185) * (Full Depth) ^ 1/6   Figure 1.  Types of Full and Partially Full Force Mains in SWMM 5 via Blogger http://www.swmm5.net/2013/08/what-are-types-of-force-mains-fm-in.html

How is RDII Storage Simulated in SWMM 5?

Subject:  How is RDII Storage Simulated in SWMM 5?

How is RDII Storage Simulated in SWMM 5? by dickinsonre Subject:  How is RDII Storage Simulated in SWMM 5? If you are using the SWMM 5 Rainfall Dependent Infiltration and Inflow(RDII)  feature you can also use the RDII storage parameters to change the RDII runoff by simulating the storage in the Sewershed.   The code in RDII.C as implemented by Lew Rossman of the EPA keeps track of used and unused initial abstraction or IA (Figure 1) When there is rainfall the following actions are taken: ·         The raindepth available to be convoluted by the RDII unit hydrograph method is reduced by unused IA ·         The amount of IA used up is then updated   When there is no rainfall ·         A portion of the IA already used is recovered using the recovery rate parameter and the variable IAUsed  Figure 1.  The long term effect of the RDII storage on the generated RDII Unit Hydrographs.  IA1, IA2 and IA3 are the Storage values for the short, medium and long term UH's. via Blogger http://www.swmm5.net/2013/08/how-is-rdii-storage-simulated-in-swmm-5.html

Four factors in Rainfall Dependent Infiltration and Inflow or RDII in SWMM 5

There are Four factors in Rainfall Dependent Infiltration and Inflow or RDII in SWMM 5:

There are Four factors in Rainfall Dependent Infiltration and Inflow or RDII in SWMM 5 by dickinsonre There are Four factors in Rainfall Dependent Infiltration and Inflow or RDII in SWMM 5: 1.   The fractional response to Rainfall or R from 0 to 1 2.   The Time Base of the Unit Hydrograph or T in hours * Dimensionless K Shape Factor 3.   The Sewershed Contributing Area in acres or hectares and 4.   The Maximum, Initial Abstraction and Recovery Rate for R on a Monthly Basis in units of inches, mm or mm/day, 5.   The fifth and probably the most important factor is the Rainfall via Blogger http://www.swmm5.net/2013/08/there-are-four-factors-in-rainfall.html

How is the Soil Saturated Conductivity Used in SWMM 5 Green-Ampt?

Subject:   How is the Soil Saturated Conductivity Used in SWMM 5 Green-Ampt?

How is the Soil Saturated Conductivity Used in SWMM 5 Green-Ampt? by dickinsonre Subject:   How is the Soil Saturated Conductivity Used in SWMM 5 Green-Ampt? How sensitive is the infiltration loss and rate to the Soil Saturated Conductivity parameter in the SWMM 5 Green-Ampt  infiltration method.   Figure 2 shows how the total infiltration loss and total loss rate vary as you change the soil saturated conductivity from 1 to 0.1 to 0.01 inches/hour.  Internally, Ks is used to check saturation and in the computation of the soil infiltration rate. Two of the checks are: ·         In low rainfall everything infiltrates as irate less than Infil>Ks and ·         In the check to see if the soil is already saturated.    Figure 1.  The three parameters for Green-Ampt Infiltration in SWMM 5 Figure 2.  The sensitivity of the total infiltration loss to the soil saturated conductivity in a continuous simulation via Blogger http://www.swmm5.net/2013/08/how-is-soil-saturated-conductivity-used.html

  

How is Capillary Suction Head Used in SWMM 5 Green-Ampt?

Subject:   How is Capillary Suction Head Used in SWMM 5 Green-Ampt?

How is Capillary Suction Head Used in SWMM 5 Green-Ampt? by dickinsonre Subject:   How is Capillary Suction Head Used in SWMM 5 Green-Ampt? How sensitive is the infiltration loss and rate to the capillary suction head parameter in the SWMM 5 Green-Ampt  infiltration method.   Figure         1 shows how the total infiltration loss and total loss rate vary as you change the suction head from 12 to 6 to 3 inches.    Internally the suction head is used in infil.c of SWMM 5 by adding the suction head to the ponded water on the pervious area in the parameter c1 of the implicit Green-Ampt SWMM5 solution. C1 =  (Suction Head + Depth of Ponded Water) * IMD or Initial Moisture Deficit    Figure 1.  The sensitivity of the total infiltration loss to the capillary suction head in a continuous simulation via Blogger http://www.swmm5.net/2013/08/how-is-capillary-suction-head-used-in.html

How Does the Green Ampt Initial Moisture Deficit Work in SWMM 5?

Subject:   How Does the Green Ampt Initial Moisture Deficit Work in SWMM 5?

How Does the Green Ampt Initial Moisture Defiict Work in InfoSWMM and SWMM 5? by dickinsonre Subject:   How Does the Green Ampt Initial Moisture Defiict Work in InfoSWMM and SWMM 5? This graph shows the values of the internal SWMM 5 parameters for Green Ampt Infiltration for the pervious area of a Subcatchment during a simulation.  The parameters are: ·         Soil Moisture = IMD Max – (FUMax – FU)/Upper Soil Zone Depth ·         FU or current moisture content of the upper zone of the of the soil ·         FUMax which is the saturated moisture content of the upper zone in feet and stays constant during the simulation ·         IMD Max is the user defined Initial soil moisture deficit and is a fraction Figure 1.  How Soil Moisture changes over time. Figure 2.  Soil Moisture and IMD are related – the Soil Moisture has a maximum of IMDMax. via Blogger http://www.swmm5.net/2013/08/how-does-green-ampt-initial-moisture.html

How Does Green Ampt Cumulative Event Infiltration work in SWMM 5?

Subject:   How Does Green Ampt Cumulative Event Infiltration work in SWMM 5?

How Does Green Ampt Cumulative Event Infiltration work in SWMM 5? by dickinsonre Subject:   How Does Green Ampt Cumulative Event Infiltration work in SWMM 5? This graph shows the values of the internal SWMM 5 parameters for Green Ampt Infiltration for the pervious area of a Subcatchment during a simulation.  The parameters are: ·         F or FTOT which is the cumulative event infiltration at the start of a time interval in the internal units of feet in SWMM 5, ·         FU or current moisture content of the upper zone of the of the soil ·         FUMAX which is the saturated moisture content of the upper zone in feet and stays constant during the simulation  Figure 1.  How FTOT, FU and F change over time Figure 2.  A closer look at how FTOT or F and FU Change over time in a Green Ampt Pervious Area Simulation. via Blogger http://www.swmm5.net/2013/08/how-does-green-ampt-cumulative-event.html

How are Negative Transect Elevations Used in SWMM5?

Subject:   How are Negative Transect Elevations Used in SWMM5? 

How are Negative Transect Elevations Used in SWMM5? by dickinsonre Subject:   How are Negative Transect Elevations Used in SWMM5? You can have negative elevations in the Transects of SWMM 5 as the elevations are transformed internally to relative depths above the node inverts in the SWMM 5 engine (Figure 1).   The slope of the link is calculated from the link offset elevations (Figure 3) and the cross sectional information for the irregular link in SWMM 5 (Figure 2) is computed from the Transect data (Figure 4).   The Water Surface elevation of the link is based on the node inverts (Figure 5). Figure 1.  Transect Editor of SWMM 5 Figure 2.  The Transect Data is Used in the Irregular of HEC-RAS Shape of SWMM 5 Figure 3.  The slope of the link with the Transect is calculated from the link upstream and downstream offset elevations – not the Transectdata which is relative. Figure 4.  Transect Data Transformed into Tables of Area, Hydraulic Radius and Width from the Transect Data internally in SWMM 5. Figure 5.  HGL of the Water Surface Elevation from the Node Invert and Link Offset Elevations. via Blogger http://www.swmm5.net/2013/08/how-are-negative-transect-elevations.html