# Category: Hydrology

Posts about runoff, groundwater, infiltration, RDII etc

## SWMM 5 Precipitation Options

Subject:  SWMM 5 Precipitation Options

You can have design storms, monitored storms of any length of the time from minutes to centuries, use intensity, volume or cumulative precipitation, use both rainfall and

## Runoff Routing Options Example in SWMM 5

Subject:   Runoff Routing Options Example in SWMM 5

There are six options for runoff routing in SWMM 5:

·         All Runoff to an Outlet Node

·         All Runoff to another Subcatchment

·         All

## Sensitivity Analysis in InfoSWMM and H2OMAP SWMM

Subject:  Sensitivity Analysis in InfoSWMM and H2OMAP SWMM

It is easy to perform sensitivity analysis in InfoSWMM and H2oMAP SWMM using the Scenario Manager, Dataset manager, Block

## How is the Volume Calculated in the SWMM 5 Groundwater Component?

Subject:   How is the Volume Calculated in the SWMM 5 Groundwater Component?

The groundwater component of SWMM 5 is found in the gwater.c code.  It (as is all of SWMM 5) is

## How is the Mass Balance Calculated in the SWMM 5 Groundwater Component?

Subject:   How is the Mass Balance Calculated in the SWMM 5 Groundwater Component?

The groundwater component of SWMM 5 is found in the gwater.c code.  It (as is all of SWMM 5

## The Groundwater Flow Component in SWMM5

Subject:  The Groundwater flow in SWMM 5 Groundwater

The Groundwater flow in SWMM 5 is actually made up of three components:

1.   groundwater flow computed from the coefficient a1 and exponent b1…

## Detention Pond Infiltration and Evaporation Losses in SWMM 5

Subject:  Detention Pond Infiltration and Evaporation Losses
You can also add a storage pond infiltration and surface evaporation losses to the pond.  The surface evaporation is

## Additional Suite Features in InfoSWMM and H2OMAP SWMM

1.   Dry Flow Allocation for your Sanitary or Combined Sewer Model
2.   Subcatchment Manager to estimate the impervious, slope, width

## InfoSWMM 11 (for ArcGIS 9, 10) and H20MAP SWMM v10 Updated for the new SWMM 5.0.022 Engine

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EPA SWMM 5 Build 5.0.022 (04/21/11)
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1. The following fixes and updates were made to the LID module of the code (lid.c):

a. The Drain …

## Tributary Area to a Node in SWMM 5 or InfoSWMM

Note:  Tributary Area to a Node in SWMM 5 or InfoSWMM
Here are the steps you neeed to take to calculate the tributary area of a node in InfoSWMM:

## Drainage Wells or a Vertical Exfiltration Trench in InfoSWMM

Subject:  Drainage Wells or a Vertical Exfiltration Trench in InfoSWMM

Note, this is just one way to model an Exfiltration Trench.  The source for the image below is Rice Creek Watershed

## Pump / Force Main System in InfoSWMM and SWMM 5

Subject:  Pump / Force Main  System in InfoSWMM and SWMM 5

The basic system consists of:

1.          Wet Well and its associated physical parameters,
2.          Pump Type
3.          Defined Pump Curve,
4.          Downstream Pressure Node and
5.          Downstream

## How to change the Maximum Infiltration in a DB Table of InfoSWMM and H2OMAP SWMM

Note:  How to change the Maximum Infiltration in a DB Table of InfoSWMM and H2OMAP SWMM

There are a lot of methods in InfoSWMM and H20MAP SWMM to change the infiltration data.  You

## The Time Base is T + T*K from the Time(T) and Storage (K) values for RDII in SWMM5

Note:  Each of the RDII UH’s has a base time for the convolution of the RDII from each UH.  The Time Base is T + T*K from the Time(T)

## SWMM 5 Aquifer has a Saturated and Unsaturated Zone

Note:  The unsaturated upper zone soil moisture varies between the initial upper zone moisture fraction to the porosity fraction for the soil.  The soil moisture content is for the SWMM5 Aquifer which

## SWMM5 Runoff and Depth Relationships

Note:  The surface runoff is a non linear function of the independent depth in both the pervious and impervious areas of the subcatchments.   No surface runoff occurs until the depth over either the

## SWMM5 Groundwater Flow Components

Note:  There are three sub flow components in the calculation of the groundwater flow from a SWMM 5 Subcatchment.

1st ComponentFlow = Groundwater Flow Coef. * (LowerDepth – Aquifer Bottom

## SWMM 5 Subcatchment Runoff and Depth Relationship

Note:  The surface runoff is a non linear function of the independent depth in both the pervious and impervious areas of the subcatchments.   No surface runoff occurs until the depthover either the

## What are the LID Control Flow Source Options in SWMM 5?

What are the LID Control Flow Source Options in SWMM 5?

The SWMM 5 options for Low Impact Development (LID) controls on a Subcatchment are very flexible, exciting, possibly

## The relationship between the rainfall, total losses from the previous area, evaporation and infiltration only rate for SWMM 5

Subject:  The relationship between the rainfalltotal losses from the previous areaevaporation and infiltration only rate.

The total loss from a subcatchment pervious area is the sum of the …

## EPA National Stormwater Calculator

Released today by the EPA (Dr Lewis Rossman) is a USA Nationwide Stormwater Calculator

Here is a new tool, based on SWMM, that may be of interest. It provides non-modelers with a quick