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EPA SWMM5 update history
The history of SWMM5 updates (from the first official release in October 2004 to the current SWMM5.0.022) is listed below in reverse chronological order.
SWMM 5.0 Update History
Build 5.0.022 (04/21/11)
1. The following fixes and updates were made to the LID module of the code (lid.c):
- a. The Drain Delay time for a Rain Barrel LID is now correctly converted internally from hours to seconds.
- b. The meaning of the Conductivity property of an LID's Storage layer has been changed. It is now defined as the saturated hydraulic conductivity of the native soil below the layer instead of the conductivity of the layer itself.
- c. Storage layers are now optional for Bio-Retention Cells and Permeable Pavement LIDs by allowing the layer height to be zero. One should still enter a non-zero conductivity for the layer if infiltration into native soil is allowed.
- d. If the top width of the overland flow surface for an LID is zero then any excess water above the surface storage depth simply spills out instantaneously.
- e. The calculation of infiltration in a Vegetative Swale was corrected so that a swale with vertical sides will produce the same results as a fully pervious subcatchment with the same dimensions, roughness, and slope.
- f. The water initially stored in all LID units is now reported in the Status Report's Runoff Continuity table.
- g. Error messages are now generated if the surface layer vegetation volume fraction is less than 1, if the area of all LIDs in a subcatchment is greater than the total area or if the total capture area of all LIDs is greater than the subcatchment's total impervious area.
2. Missing values for accumulation periods within an NWS rain file are now processed correctly. See rain.c.
3. A new error message (318) is now generated if a user-prepared rainfall file has its dates out of sequence. See rain.c, err.h, and err.c.
4. Evaporation during wet time periods was including rainfall and run-on as moisture available for evaporation when it should only be the current ponded depth. See subcatch.c.
5. Curve Number infiltration was modified to use only direct precipitation, not including runon or internally routed flow, to compute an infiltration rate. See infil.h, infil.c, subcatch.c and lid.c.
6. A new error message (110) is now generated if the ground elevation of a subcatchment is less than the initial water table elevation of its groundwater aquifer. See gwater.c, err.h, and err.c.
7. A check was added to the tailwater term of the groundwater flow equation to insure that the term is zero when no tailwater depth exists. See gwater.c.
8. Checks were added to the solution of the governing groundwater mass balance equations to catch conditions where the lower zone depth is greater than the total depth or when the upper zone moisture content is greater than the porosity. See gwater.c.
9. A divide by zero error no longer occurs when computing the hydraulic radius of an empty Filled Circular pipe whose filled depth is zero. A similar error for the hydraulic radius of an empty trapezoidal channel whose bottom width was zero was also eliminated. See xsect.c.
10. The critical or normal depth adjustment made for a conduit is no longer allowed to set the depth to zero -- some small depth level is always maintained. See dynwave.c.
11. The Pump Summary Report was expanded to include number of start- ups, minimum flow, and time off both the low and high ends of the pump curve. See objects.h, link.c, stats.c, and statsrpt.c.
12. When the setting of an orifice or weir was changed to 0 (to completely block flow) the flow depth in the element wasn't being set to 0. This was only a reporting error and had no effect on the flow routing calculations. See link.c.
13. The Node Surcharge Summary in the Status Report did not report a ponded node as being surcharged. This was only a reporting error and had no effect on the flow routing calculations. See stats.c.
1. A new map view variable for subcatchments, the percent of area occupied by LID controls, was added. This view allows one to easily distinguish which subcatchments have been assigned LIDs and which haven't.
2. The LID Control Editor now checks to see that data fields that require fractions (such as vegetative volume, void volumes, soil porosity, etc.) contain valid entries.
3. The LID Group Editor now checks that the total area of all LIDs assigned to a subcatchment does not exceed the area of the subcatchment and that the total percentage of impervious area treated by these LIDs does not exceed 100.
4. Comments applied to Time Patterns are no longer lost when a project is saved and re-opened at a later time.
5. The File | Export | Hostart option now saves the current groundwater state correctly.
Build 5.0.021 (09/30/10)
1. A code refactoring error in build 5.0.019 that resulted in no recovery of infiltration capacity during dry periods has been fixed. See subcatch.c.
2. The pervious area adjustment used in 5.0.019 for evaporation and infiltration to a subcatchment's groundwater zone was corrected. See gwater.c.
3. The accounting of evaporation loss from just the pervious area of a subcatchment has been corrected. See subcatch.c.
4. The rainfall + runon used to compute infiltration is no longer pre-adjusted by subtracting any evaporation loss. See subcatch.c.
5. The rate for Green-Ampt infiltration is no longer allowed to be less than the smaller of the saturated hydraulic conductivity and the available surface moisture. See infil.c.
6. The available surface moisture for Green-Ampt infiltration is considered 0 if its value is less than a small tolerance. See infil.c.
7. Evaporation and infiltration losses from Storage nodes under Kinematic Wave and Steady Flow routing are now accounted for properly. See flowrout.c.
8. The Pollutant Loading summary tables in the Status Report now lists results for all pollutants in a single table instead of listing just 5 pollutants per table. See report.c.
1. The anchoring of the components on either side of the splitter bar on the Data Browser panel was changed to insure that the main window is displayed correctly when SWMM is first launched.
2. The incorrect display of link slopes on the study area map under the Elevation Offsets option was corrected.
Build 5.0.020 (08/23/10)
1. A refactoring bug that prevented SWMM from reading rainfall data from external rainfall files was fixed. See gage.c.
Build 5.0.019 (07/30/10)
1. The ability to explicitly model five different types of Low Impact Development (LID) practices at the subcatchment level has been added. Consult the LID Controls topic in the Help file for details. See lid.c, lid.h, infil.c, infil.h, input.c, inputrpt.c, project.c, statsrpt.c, and subcatch.c.
2. Pollutant buildup over a given landuse can now be specified by a time series instead of just a buildup function. Consult the Land Uses / Buildup topic in the Help index for more details. See landuse.c and keywords.c.
3. An option was added to allow evaporation of standing water to occur only during periods with no precipitation (the default is the current practice of allowing evaporation in both wet and dry periods). See climate.c, enums.h, keywords.c, objects.h, project.c, subcatch.c, and text.h.
4. Storage node losses from evaporation and infiltration are now computed directly within the flow routing routines to produce better conservation of mass. See objects.h, routing.c, dynwave.c and node.c.
5. The check to see if flow in a link should not exceed the normal flow now uses just the upstream Froude number rather than both up and downstream numbers. See dynwave.c.
6. The maximum trials used when evaluating the flow and head equations at a given time period for dynamic wave routing was increased from 4 to 8. See dynwave.c.
7. The Ponding calculation for dynamic wave flow routing was changed once again to obtain better continuity results. The depth in a surcharged node that can pond is not allowed to rise higher than just beyond full depth in any single time step. After that, its change in depth is determined by the node's ponded area. Similarly, the depth of a ponded node is not allowed to drop more than just below full depth in any single time step. See dynwave.c and node.c.
8. For Kinematic Wave and Steady Flow routing, a node's ponded area is no longer used to infer a ponded depth when a node floods with Ponding turned on. Instead, the water depth is simply set to the node's maximum depth and the ponded area parameter is simply used as a indicator as to whether the node can pond or not. (This differs from dynamic wave routing where the ponded area directly influences ponded depth through the solution of the momentum and flow conservation equations.) See flowrout.c.
9. As a consequence of the preceeding update, the Node Flooding Summary table in the Status Report no longer displays the maximum ponded volume in acre-inches (or hectare-mm). Instead it displays the maximum ponded depth (ft or m) for Dynamic Wave flow routing or the maximum ponded volume (1000 ft3 or 1000 m3) for other forms of routing. See stats.c and statsrpt.c.
10. The groundwater mass balance equations were returned to the form they had in release 5.0.013 since they were not correctly accounting for the water volume transferred between the saturated and unsaturated zones due only to a change in the water table depth. See gwater.c.
11. Controls based on flow rates now properly account for the direction of flow when they are evaluated. This may require users to add an extra condition clause to a rule that only applies for flow in the positive direction (e.g., AND Link XXX FLOW >= 0.0). See controls.c.
12. The Villemonte correction for downstream submergence is now also used for partly filled orifices (instead of just for weirs). See link.c and dynwave.c.
13. A missing term in the equation used to check for submerged inlet control for Culvert conduits was fixed. See culvert.c.
14. If a non-conduit link is connected to a storage node then its contribution to the node's surface area is now ignored. See dynwave.c.
15. The automatic adjustment of the maximum depth of a link's end nodes to be at least as high as the link's crown no longer applies when the link is a bottom orifice. See link.c.
16. A fatal error message is now generated if a conduit's entrance, exit, or average loss coefficient value is negative. See link.c.
17. Requests to do internal routing of runoff between impervious and pervious sub-areas of a subcatchment when only one type of sub-area exists are now ignored. See subcatch.c.
18. The check on the error condition of a node having both incoming and outgoing dummy conduits was modified so as not to get fooled by Outlet-type links. See toposort.c.
19. The Ignore Snowmelt switch is now internally set to true whenever there are no snow pack objects defined, so that precipitation is not mistakenly converted to snow for a project with temperature data. See gage.c and project.c.
20. When reading min/max daily temperatures from a climate file, the values are now swapped if the minimum is greater than the maximum. See climate.c.
21. When the Hargreaves method is used to compute an evaporation rate from daily temperature values, negative rates are no longer allowed. See climate.c.
22. Several bugs that prevented SWMM from detecting and reading Canadian DLY02/04 climate files correctly were fixed. See climate.c.
23. An error message is now generated if a time series used for rainfall is also used for another purpose in a project (since it will cause the two uses to be out of synch). See error.h, error.c, gage.c, climate.c, control.c, and inflow.c.
24. An error message is now generated if two Rain Gages with files as their data source use the same Station IDs but different names for the data file. See rain.c, error.h, and error.c.
25. When zero rainfall values appear in a rain file or time series they are now skipped over and treated as a dry period, the same as would occur had they not been entered in the first place. See gage.c.
26. A bug that caused the data in an evaporation time series to be out of synch with the simulation time clock has been fixed. This only affected evaporation data supplied from time series and not monthly average data or data from climate files. See climate.c.
27. The water quality mass balance now correctly accounts for any initial mass in the system created by using a hot start file. See massbal.c.
28. For models that only compute runoff and have a reporting time step less than the wet time step, the latter is internally set equal to the former. See swmm5.c.
1. The Data Browser was updated to include the newly added Low Impact Development (LID) objects and new dialog forms were added to specify LID design data and their placement within a project's subcatchments.
2. You can now open a project input file by dragging it from Windows Explorer (or the Desktop) and dropping it anywhere in SWMM's main window.
3. A new checkbox was added to the Evaporation page of the Climatology Editor to include the option to evaporate only in dry periods.
4. The choices for Function type on the Buildup page of the Land Use Editor were extended to include an external time series (EXT).
5. SWMM will now continue to use the period (".") as the decimal separator even if the user or the system changes the Windows Regional Settings while the program is running.
6. A new installer program is now used that places the example data sets in the user's My Documents\EPA SWMM Projects folder.
7. The components below the horizonal splitter bar on the Data Browser panel were placed in their own panel component so that the splitter would work correctly under Windows 7.
Build 5.0.018 (11/18/09)
1. Reporting of the total infiltration + evaporation loss for each Storage Unit (as a percent of total inflow to the unit) was added to the Storage Volume Summary table in the Status Report. See objects.h, node.c, stats.c, and statsrpt.c.
2. Double counting the final stored volume when finding the nodes with the highest mass balance errors has been eliminated. See stats.c.
3. A warning message was added for when a Rain Gage's recording interval is less than the smallest time interval appearing in its associated rainfall time series. (An error message is issued if the recording interval is greater than the smallest time series interval.) See gage.c and text.h.
4. Hot Start interface files now contain the final state of each subcatchment's groundwater zone in addition to the node and link information they have always had. See routing.c.
5. To avoid confusion, the actual conduit slope is now listed in the Link Summary table of the Status Report rather than the adjusted slope that results from any conduit lengthening. See link.c and dynwave.c.
6. The Status Report now displays only those summary tables for which results have been obtained (e.g., if the Flow Routing option is turned off, then no node or link tables are displayed). See massbal.c and statsrpt.c.
7. Some code re-factoring was done to place rain gage validation and initialization in separate functions. See project.c, gage.c, and funcs.h.
8. The engine version number was updated to 50018 (this update had been overlooked since release 5.0.010). See consts.h.
1. A bug that prevented Status Report files from being deleted from a users TEMP folder when they were no longer in use was corrected. Users should check their TEMP folders (usually in c:\Documents and Settings\
\Local Settings\Temp) for old files that begin with "swm". These can safely be deleted.
2. The project input file created for use by SWMM's Add-On Tools now contains all project data, including map coordinates and element tags.
Build 5.0.017 (10/7/09)
1. The Ponding routine for dynamic wave flow routing was once again modified, this time to account for the special case where a node transitions between surcharged and ponded conditions within a single time step. This should correct the large continuity errors experienced with ponding under release 5.0.016. See dynwave.c.
2. Error 112 (a conduit's elevation drop exceeds its length) is now treated as a Warning condition and not a fatal error. In this case the conduit's slope is computed as in earlier versions of SWMM (elevation drop / length) instead of using the more rigorous right-triangle method of HEC-RAS. See link.c and text.h.
3. Inflow interface files no longer have to contain data for all of the same pollutants defined in the current project (e.g., they can contain just flows or some subset of the pollutants). See iface.c.
4. Instead of using the rain gage's recording interval as the time step for processing a set of RDII unit hydrographs, the smaller of the wet runoff time step and the time to peak of the shortest unit hydrograph in the set is now used. As a result, it is now permissible to use hydrographs whose time to peak is shorter than the rain gage recording interval. See rdii.c.
5. Under Curve Number infiltration, infiltration now stops when the maximum capacity (initially equal to 1000/CN - 10 inches) is completely used up. See infil.c.
6. The small tolerance used to determine how much ponded depth in excess of depression storage is needed to initiate runoff was removed. This produces a smoother runoff response for some data sets. See subcatch.c.
7. A default concentration for dry weather flow has been added to the Pollutant object. It can be overriden for any specific node by editing the node's Inflows property. See landuse.c, routing.c, and objects.h.
8. For water quality routing, the simplified analytical solution to the CSTR mixing equation was replaced with a more robust finite difference approximation. This seems to avoid numerical problems with high decay rates. See qualrout.c.
9. First order decay was not being applied to pollutants transported through conduits under Steady Flow routing. To do this correctly required writing a special water quality routine just for Steady Flow routing. See qualrout.c.
10. A small minimum depth tolerance was introduced for treatment to occur at nodes and to have non-zero concentrations in conduits. See qualrout.c.
11. Large water quality mass balance errors in systems that provide treatment at nodes were eliminated by correctly accounting for both the inflow mass and mass in storage when computing the mass lost to treatment. See treatmnt.c.
1. The property editor for Pollutant objects was modified to accommodate the new default dry weather flow concentration property.
2. The default dry weather runoff time step was reduced from 15 to 5 minutes and the default total duration was changed from 0 to 6 hours.
3. The Ruler tool now displays a small square where the user begins their measurement so that its easier to create a closed polygon when measuring an area.
Build 5.0.016 (6/22/09)
1. A new option was added to compute daily evaporation from the daily temperature values contained in a climate file using Hargreaves' method. (See climate.c, enums.h, keywords.h, and text.h).
2. When the Ponding option is turned on, nodes that can pond are no longer always treated like storage nodes that never surcharge. Now they are only treated this way after ponding occurs. Otherwise they behave like a normal node. (See dynwave.c).
3. The small tolerance used to decide when a storage node was full or not has been removed since for very small time steps it could cause a currently full storage unit to remain full even if there was some small net outflow from it. (See node.c).
4. Spurious warnings for negative elevation offsets no longer appear when the "*" entry is used for the offset value or when the offset elevation value is within a small tolerance of the node invert elevation. (See link.c).
5. When the water level at a storage node exceeds the highest level supplied in its Storage Curve, an extrapolated surface area from the curve is now used only if the curve is sloping outward (i.e., surface area is increasing with depth at the top of the curve). If instead it slopes inward then the last surface area entry in the curve is used. (See table .c).
6. Comma delimited NCDC rainfall files, both with and without station name, can now be recognized and read correctly by SWMM. (See rain.c).
7. Space delimited NCDC rainfall files with empty spaces in the condition code fields can now be read correctly. (See rain.c).
8. A bug created in release 5.0.015 that caused incorrect RDII inflows to be computed when the rain gage recording interval was less than the runoff wet time step has been fixed. (See rdii.c).
9. A new error check was added to detect if the time base of an RDII unit hydrograph is less than its rain gage recording interval. (See rdii.c).
Build 5.0.015 (4/10/09)
1. Storage unit nodes have a new optional property named Infiltration
that can store Green-Ampt infiltration parameters for the unit and
thus allow it to serve as an infiltration basin. The Green-Ampt
infiltration model was modified to explicitly include the effect
of ponded water depth on infiltration rate. (See infil.c,
massbal.c, node.c, and objects.h).
2. Different sets of Initial Abstraction parameters (maximum depth,
initial depth, and recovery rate) can now be specified for each
of the three unit hydrographs (short term, medium term, and long
term) that comprise an RDII Unit Hydrograph group (see keywords.h,
keywords.c, objects.h, rdii.c, and text.h).
3. A Meander Modifier was added to a Transect's parameters. It is the
ratio of the length of a meandering main channel to the length of
the overbank area that surrounds it. This modifier is applied to
all conduits that use this particular transect for their cross
section. It assumes that the length supplied for these conduits is
that of the longer main channel. SWMM will use the shorter overbank
length in its calculations while internally increasing the main
channel roughness to account for its longer length. (See dynwave.c,
flowrout.c, link.c, objects.h, and transect.c).
4. NWS files in space delimited TD 3240 or 3260 format that include a
station name field have been added to the types of rainfall files
that are automatically recognized by SWMM (see rain.c).
5. The 2 GB binary output file size limit for runs made under the GUI
that was inadvertently added into release 5.0.014 was removed
6. Any backflow that flows into an outfall node due to the head
condition at the node is now correctly reported as part of the
node's Total Inflow result (see node.c).
7. A fatal error is now generated if the smallest time interval between
values in a rainfall time series does not match the recording time
interval specified for the associated rain gage object (instead of
internally adjusting the gage interval and issuing a warning message)
(see error.c, error.h, and gage.c).
8. The normal flow limitation for dynamic wave flow routing based on
the Froude number now requires that the latter be greater or equal
to 1.0 for both the upstream and downstream flow depths rather just
for either of these (see dynwave.c).
9. An reporting error for the overflow rate into the ponded volume for
a node that floods under dynamic wave flow routing was corrected
10. The practice of not allowing a computed top surface width to be less
than the width at 4% of the full conduit depth for dynamic wave flow
routing has been dropped in favor of using the actual width, no matter
how small (see dynwave.c).
1. Data entry forms were modified to support the new modeling features
described in the Engine Updates items (1) - (3).
2. A problem with the way that conduits with elevation offsets were
displayed in profile plots drawn prior to a run was corrected.
Build 5.0.014 (1/21/09)
Rain Gages (gage.c, table.c, error.c, error.h, and objects.h)
1. The recording interval for a rain gage is now automatically adjusted
to be no greater than the smallest time interval for the gage's time
series data (with a warning message written to the Status Report).
2. When two or more rain gages reference the same time series data, a
fatal error message is now generated if the Rainfall Formats
(intensity, volume, or cumulative volume) for the gages are not all
3. The Green-Ampt infiltration rate was corrected for the case when
the surface becomes saturated part way through the current time step.
4. The saturated hydraulic conductivity is no longer needed by the
Curve Number method to compute a regeneration rate for infiltration
capacity. The latter is now set simply to the reciprocal of the user
supplied drying time. Thus the CN method now requires only two param-
eters (the CN and the drying time).
5. An optional monthly adjustment pattern can now be used to modify the
recovery rate of infiltration capacity by month of year. The name of
this pattern is specified as part of the Evaporation data. See the
Help file or the Users Manual for details. (This also affects files
climate.c, keywords.c, project.c, enums.h, objects.h, and text.h).
Flow Routing (flowrout.c, node.c, inflow.c, link.c, and objects.h)
6. A new Minimum Slope option has been added. When this option is non-
zero a computed conduit slope is not allowed to be below this value.
The default is 0. (Note: the slope of a conduit whose elevation
difference is below 0.001 ft is first computed using this elevation
difference and then is compared to the Minimum Slope value.) (The
following files were also changed for this feature: keywords.c,
project.c, enums.h, globals.h, text.h).
7. An optional Baseline Time Pattern was added for external inflows at
nodes. It can be used to apply a periodic adjustment to the baseline
inflow value by month of year, day of week, etc. See the Help file or
the Users Manual for more details.
8. Specific conduits can now be designated as Culverts and have Inlet
Control flow computed for them under Dynamic Wave flow routing.
9. The rating curve used to determine flow through an Outlet can now be
based on either the freeboard depth above the outlet bottom (as
before) or on the head difference between the upstream and downstream
10. The calculation of the maximum outflow that a node can release over
a time step should be based on the initial volume, not the final
volume, at the node.
11. A problem with the program not accepting an ideal pump when the
connecting upstream conduit had an adverse slope was fixed.
12. The formula used to compute conduit slope was modified to match that
used by HEC-RAS.
13. A problem with the program crashing when the No Routing option was
selected in combination with the Save Outflows Interface File option
was fixed (see output.c).
14. Under Steady Flow and Kinematic Wave routing one can now use a Dummy
conduit that connects to a node at higher elevation without having
to specify an inlet offset.
Dynamic Wave Flow Routing (dynwave.c, link.c, and node.c)
15. Under-relaxation of flows for pumps between iterations of the
governing equations is no longer used since it can produce a
solution that does not conform to the pump's operating curve.
16. Instead of the average area, the upstream weighted area that
accounts for near-supercritical flow is now used in the dQ/dH
term for conduits.
17. The upstream/downstream Froude numbers used to check for normal
flow are now computed using hydraulic depth rather than flow depth.
18. When ponding is allowed, ponded volume is now computed from the
computed nodal depth rather than adjusting the depth to accommodate
the ponded volume based on the excess of inflow versus outflow. This
is a return to the original method that was used up until Release
5.0.010 and makes ponding (which is actually a form of storage)
consistent with the way that storage nodes are normally treated.
19. The volume at the inlet node of Type I pumps (where an implicit
wet well is assumed to occur) is now determined on the basis of
computed depth, just as with storage nodes, rather than computing
depth from the change in volume.
20. The possible closing of tide gates on outfalls directly connected
to orifice, weir, or outlet links is now correctly accounted for.
Conduit Cross-Sections (xsect.c)
21. The modified baskethandle (MODBASKETHANDLE) cross-section shape
was extended to allow the circular top to have any desired radius
equal or greater than half the section's width. It thus becomes
an upside down version of the Rectangular-Round shape. The section
geometry functions for both shapes received extensive revision.
Control Rules (controls.c)
22. "SIMULATION MONTH" and "SIMULATION DAY" (meaning month of the year
and day of the week, respectively) have been added to the types of
time conditions that can be used in a control rule condition clause.
Pollutant Buildup/Washoff (subcatch.c, landuse.c, and consts.h)
23. Washoff of a user-specified initial buildup when there is no buildup
function specified now works correctly.
24. The way that concentrations in runoff are combined with those
from runon and direct rainfall was modified so as to produce more
consistent results, especially when a BMP removal value is appled.
Water Quality Routing (qualrout.c, routing.c, treatmnt.c)
25. For storage units, the finite difference form of the mass balance
equation was replaced with the analytical CSTR solution.
26. An inflow rate adjustment was added when routing quality through
conduits under Dynamic Wave flow routing to help lower the mass
27. The formula for updating the hydraulic residence time (HRT) in a
storage node was revised.
28. Quality routing under Steady Flow routing is now treated as a
special case where the concentration within a conduit simply equals
that of the upstream node.
29. Any reverse flow into the system that occurs at an Outfall node is
now treated as an external inflow with respect to water quality and
will therefore contain whatever pollutant concentration was specified
for external inflows at the node even if no external flow inflow was
defined. This feature can be used to model saltwater or contaminant
intrusion in tidally influenced channels.
30. The mass balance equations were re-formulated in a simpler fashion.
31. The flow equation was re-expressed in terms of distances above the
aquifer bottom instead of absolute elevations.
32. The equation for computing the maximum infiltration rate that the
upper zone can accept was corrected.
33. Snow removal for a subcatchment now works by removing snow once the
"Depth at which removal begins" is reached. The fraction of this
amount that remains on the surface is whatever is left over after
all of the redistribution options are satisfied.
34. The "Depth at which removal begins" value is now correctly converted
to internal units of feet.
35. A problem with no RDII being produced when two or more RDII unit
hydrographs utilized the same rain gage was fixed.
Time Series (table.c, error.c, error.h, objects.h)
36. Time Series data can now be imported from an external file instead
of having to be listed in the project's input file. See the Users
Manual or the Help file for details.
37. A user can now choose to ignore any combination of the following
process models when running a simulation: Rainfall/Runoff, Snowmelt,
Groundwater, Flow Routing and Water Quality (swmm5.c, project.c,
runoff.c, subcatch.c, routing.c, keywords.c, keywords.h, text.h,
Status Report (statsrpt.c)
38. The heading for the maximum flow column in the Link Flow Summary table
was changed to "|Flow|" to show that the flows listed are absolute
39. The labels "Mgal" and "Mltrs" were replaced with "10^6 gal" and
"10^6 ltr", respectively.
40. The widths for the various types of flow volume fields (e.g., runoff
volume, node inflow volume, etc.) were increased in size.
Binary Output File (output.c)
41. The Report Start Time written to the binary results is now
adjusted to be be one reporting period prior to when the first
result is reported so that the GUI uses the correct date when it
Output Report (command line version) (report.c)
42. Time series tables for reported subcatchments now report Snow Depth,
Groundwater Elevation, and Groundwater Flow (provided that snowmelt
and groundwater processes are included in the simulation).
1. Support was added for the following new engine features:
a. minimum conduit slope option
b. culvert designation for specific conduits
c. monthly infiltration recovery Pattern
d. Baseline Time Pattern for external inflows
e. updated Modified Baskethandle cross-section shape
f. either depth-based or head-based Outlet rating curves
g. options to ignore selected process models
h. use of an external file as source of time series data.
2. Regarding 1h above, the Time Series Editor dialog was modified to
include the external data file option.
3. A new category of Simulation Options named Reporting has been
added. When this category is selected for editing in the Data
Browser, a Reporting Options dialog appears from which one can
limit the number of objects whose simulation results are saved
and can be reported. The default is to save results for all
4. The Group Editing feature was extended to include subcatchment
Snow Packs and Groundwater Flow parameters.
5. The Help -> Tutorial menu command now works correctly to launch the
newer HTML version of the SWMM5 Tutorial Help file.
6. The File -> Export -> Hotstart File command now converts metric
results to internal SWMM US units before saving them to the hotstart
7. Commas are no longer recognized as item separators when reading input
files since this was causing problems when a comma was used in the ID
name of an object (which is allowable).
8. The coordinates of the default natural areal depletion curve for snow
packs were changed to correspond to those appearing in the National
Weather Service publications on which SWMM's snow melt routines were
9. A problem with not loading a specified startup input file when
epaswmm5.exe is launched from the command line (or from an Explorer
shortcut) was fixed.
10. A problem with the simulation progress meter not displaying the correct
number of elapsed days during long-term simulations was fixed.
11. A problem with Profile Plots not being updated correctly when users
changed certain display options was corrected.
12. The following updates to the Profile Plot feature were made:
i. The selected links are now checked to make sure that they exist
and form a connected path.
ii. The vertical axis scaling can now be set from the Profile Plot
iii. The filled-in water level at junctions is now drawn only as high
as the maximum junction depth (i.e., the ground surface), even if
the HGL is higher.
13. A problem with copying just a single column of a Tabular Report to the
clipboard or to a file was corrected.
14. A problem with the selection buttons on the Time Series and Tablular
Report Selection dialog becoming stuck in the disabled mode was fixed.
15. If an external file (such as a rainfall climate, or interface file)
resides in the same directory as the project file then the directory
path portion of the file name is omitted when the file name is saved
within the project file. This will make it easier to share project
files with other users and computers.
16. The name of the "Rainfall" theme variable was changed to "Precipitation".
17. When the Auto-Backup program preference is selected, a backup file is now
created whenever the current project file is saved to disk, not just when
the project is first opened.
Build 5.0.013 (3/11/08)
1. The check on acceptable values for site latitude was
corrected (see climate.c).
2. The definition and implementation of the PID controller
was changed. See the Help file or the Users Manual for
details (see controls.c).
3. The following changes were made to the dynamic wave flow
routing routine in dynwave.c:
a. A new method that places more weight on upstream conduit
geometry as the Froude number approaches 1 was added.
b. A code re-factoring error that crept into the inertial
term of the momentum equation was corrected.
c. The flow in a fully flowing open channel can no longer be
greater than the full normal flow.
d. The Normal Flow Limit based on both slope and Froude number
was modified to simply implement the two criteria together
in the same fashion as they are done individually.
e. A check was added that prevents any flow out of a node that
f. The ponding computation was reverted back to that of 5.0.009
(depth is computed from volume rather than volume computed
from depth) to better maintain flow continuity.
g. Using the maximum allowable change in depth at a node as a
criterion for selecting a variable time step was restored.
4. The crown elevations of any connecting non-conduit links are
now considered when determining a node's crown elevation (see
5. The possibility that the initial setting of an orifice was not
being made correctly was eliminated (see link.c).
6. Error checks were added to test for invalid numbers in a hot
start file (see routing.c).
1. Checks were added to test for erroneous values in an INI file
that would prevent a graph from displaying properly.
Build 5.0.012 (2/4/08)
1. The summary results tables written to the Status Report file
have been updated and expanded. See the Users Manual for more
details. Code changes to support this were made to dynwave.c,
flowrout.c, funcs.h, inputrpt.c (a new module), keywords.c,
keywords.h, link.c, objects.h, output.c, report.c, stats.c,
statsrpt.c (a new module), and text.h.
2. Conduit offsets can now be specified as an absolute
elevation or, as before, a relative depth above the node
invert. The same is true for the bottom of orifices, weirs,
and outlets. The "Link Offsets" setting in the GUI and the
corresponding LINK_OFFSETS entry in the project's input file
determine which option, DEPTH or ELEVATION, is in effect.
(see project.c, link.c, keywords.c, keywords.h, globals.h,
3. A PID-type controller has been added to the types of
modulated control rules that are available. See the Help
file or the Users Manual for instructions on how to use
this feature (see controls.c and keywords.c).
4. In the simulation results, "flooding" is now considered to
occur whenever the water level exceeds the top of a node,
whether ponding occurs or not. Before, flooding was only
recorded when there was no ponding and node overflow was lost
from the system (see dynwave.c, flowrout.c, massbal.c, node.c,
stats.c, and statsrpt.c).
5. The point at which the time to drain the upper soil zone for
Green-Ampt infiltration is first calculated was moved from time
0 to the time when the first rainfall period occurs. This fixes
a problem where different runoff hydrographs were being produced
when a project's start date was shifted slightly (see infil.c).
6. The criteria used to determine when steady state flow
conditions exist were changed to more closely follow those
used in SWMM 4 (see routing.c and the Help File or Users
Manual for the Skip Steady Periods option).
7. The optional user-assigned maximum flow limit for conduits was
made operational for all flow routing options, not just Dynamic
Wave routing (see link.c).
8. SI unit conversion problems for both a pump's on/off depth
settings and its pump curve slope values were fixed (see link.c).
9. The possibility that ponding could occur at the inlet (wet well)
node for a Type I pump was added (see dynwave.c).
10. A mistake in the Hazen-WIlliams head loss formula for force
main conduits was corrected (see forcmain.c).
11. The minimum limit of 0.0001 on flow area and hydraulic radius
computed from flow depth during dynamic wave routing was removed
since flow depth is already limited by this amount (see dynwave.c).
12. The flow direction test added for checking UPSTREAM CRITICAL and
DOWNSTREAM CRITICAL flow conditions in dynamic wave flow routing
was removed to prevent solutions from becoming stuck (see
13. The use of a maximum allowable change in depth at a node as a
criterion for selecting a variable time step for dynamic wave
flow routing was dropped (see dynwave.c).
14. A more refined method for computing the flow across a bottom
orifice at low heads was implemented. (see link.c).
15. The head loss calculation caused by flap gates in weirs was
extended to orifices as well (see link.c).
16. The computation of depth as a function of area for a trapezoidal
channel was extended to consider the case where the user used
0 for the side slopes (making it a rectangular channel - a
holdover from SWMM 4) (see xsect.c).
17. A bug introduced in 5.0.010 that was preventing RDII from being
computed for unit hydrographs that used the same rain gage as
another unit hydrograph was fixed (see rdii.c and objects.h).
18. Pollutant loading from RDII was corrected to be based on the
pollutant's specified RDII quality rather than its rainfall
quality (see routing.c).
19. The "Snow Only" option for the buildup of a pollutant was never
actually implemented and has now been added (see subcatch.c).
20. Additional error checking for valid snow melt and snow pack
input parameters was added (see snow.c, error.c, and error.h).
21. The same runoff threshold is now used for both pollutant washoff
(when above the threshold) and buildup (when below the threshold)
to avoid non-zero runoff concentrations from being reported
during periods with negligible runoff (see subcatch.c).
22. The values for total system outflow and system flooding that are
saved to the binary results file at each reporting time step are
now set equal to the same values that are used for computing the
overall flow continuity error, thus avoiding inconsistent system
outflow values being generated for some data sets (see output.c).
23. For the command line version of SWMM, the default END_TIME option
was corrected from being 24 days to 0 days (i.e., midnight of the
END_DATE value) (see project.c and swmm5.c).
1. The Status Bar on the bottom of the main window was given a new look,
with drop down buttons added for changing the Link Offsets convention
and the project's flow units.
2. A combo-box was added to the Nodes/Links page of the Project Defaults
dialog to select the Link Offsets convention (in addition to the
button on the Status Bar).
3. The choice of Flow Units was removed from the General Options page
of the Simulations Options dialog and placed into a drop down button
on the main window's Status Bar. (As before, one can also set flow
units from the Nodes/Links page of the Project Defaults dialog.
4. A Bookmarks panel was added to the Status Report window to make it
easier to navigate between different sections within the report.
5. A new Measurement Tool button was added to the Map Toolbar that
allows one to measure the distance of a polyline or the area of a
polygon drawn directly on the study area map.
6. Storage Units were added to the choice of objects that can be
edited using the Group Editor dialog.
7. The length assumed for non-conduit objects displayed on a profile
plot was reduced from 100 ft to 10 ft.
8. A "View Conduits Only" option was added to the Profile Plot Options
dialog that makes the plot display just the water depth in the
conduits along the profile and not show the HGL and ground surface.
This allows one to get a better view of how full a conduit is.
9. The Project Data viewer (launched when Project | Details is selected)
can now be split into two views by selecting Window | Split from its
menu bar (or Window | Remove Split to remove the split view).
10. The number of decimal places set for each computed variable on the
Number Formats page of the Program Preferences dialog is now saved
between sessions as the other preferences are.
11. Current simulation results are now always saved between sessions
(if requested by the user) even if data were modified after the
last run was made. In this case, when the project is opened again,
the Run Status icon will show that results are available but need
12. If the user changes the display format of a Date/Time axis in the
Graph Options dialog and checks the Default box in the dialog, then
this format will be used for all future time series plots for the
13. A problem with the Profile Plot dialog not always identifying the
path of fewest links between two nodes when asked to do so was
14. Entries in the [REPORT] section of a project input file that were
used to define reporting options for the command line version of
SWMM 5 will no longer be lost when the project is run under the
GUI version of SWMM. The GUI version simply ignores them but adds
them into the project file whenever it is saved.
15. Conduit lengths and areas were always being re-computed after the
study area map's dimensions or distance units were changed with the
Map Dimensions dialog rather than only when the user selected the
re-compute option on the dialog.
16. The backdrop map now pans to the correct position when the Edit |
Find Object command is used to locate an object that is currently
not in view on the staudy area map.
17. The problem of having the name of a subcatchment's outlet node
or groundwater node be lost whenever that node was converted to
another type using the study area map's right-click popup menu
18. The Statistics Report analyzer was failing to include the last
event in its calculations for some data sets.
19. Additional input validation was added to the Snow Pack editor form.
Build 5.0.011 (7/16/07
1. A bug that prevented Weir and Outlet settings from being
updated after they were changed by control rules was fixed
2. The control setting for a Weir was not being accounted
for when computing an equivalent orifice coefficient for
surcharged flow or when computing flow through a V-notch
weir (see link.c).
3. The reported depth of flow through a Weir was not taking into
account the Weir's control setting (see link.c).
4. An update made in 5.0.010 to how ponded depths and volumes are
computed under dynamic wave flow routing was corrected (see
5. The equations used to mix the quality of runon, rainfall and
ponded water over a subcatchment were revised to prevent
numerical instability at very low volumes (see subcatch.c).
6. Missing values in NCDC rainfall files that use the 'M' flag
are now added to the total number of missing records reported
1. A bug introduced in release 5.0.010 that neglected to place
quotation marks around Map Labels and backdrop file names
(which can have spaces in them) when a project was saved to
file and which caused problems when the project was re-opened
has been fixed.
Build 5.0.010 (6/19/07)
1. All "float" variables were re-declared as "doubles"
(except for those variables written to binary interface
files) and the engine was re-compiled using the Microsoft
VC++ 2005 compiler.
2. A new NO ROUTING option was added which allows a run to
ignore any flow routing and only compute runoff (see
swmm5.c, keywords.c, stats.c, and enums.h).
3. A new type of pump, an Ideal Pump, was added which pumps at a
rate equal to the inflow to its inlet node and does not use a
pump curve (see enums.h, link.c, and flowrout.c).
4. A new type of conduit shape, a Custom Shape, was added which
allows users to define their own cross-sectional geometry for
closed conduits. To implement this feature, a new type of curve,
a Shape Curve, was added which records how the width of the
cross-section varies with height. (See keywords.c, link.c,
project.c, report.c, shape.c, xsect.c, enums.h, funcs.h,
globals.h, objects.h, and text.h).
5. Another new type of conduit shape, a Circular Force Main, was
added. It is a circular pipe that uses either the Hazen-Williams
or Darcy-Weisbach equations, instead of the Manning equation,
for pressurized flow only. The Hazen-Williams C-factor or the
Darcy-Weisbach roughness height is one of the shape's parameters.
The choice of which equation to use (for Force Mains only) is a
new global option. (See project.c, forcmain.c, dynwave.c,
keywords.c, link.c, xsect.c, enums.h, globals.h and text.h).
6. Pumps can now have startup and shutoff inlet node depths supplied
directly as part of a pump's properties rather than as part of a
control rule. (See link.c, routing.c, objects.h, and funcs.h).
7. Orifices can now have timed gate openings and closings as in
SWMM 4 (i.e., the SWMM 4 ORATE parameter). (See link.c and
8. Unit Hydrographs used for RDII inflows can now have an initial
abstraction loss associated with them. Consult the Users Manual
or the Help file for details. (See rdii.c and objects.h).
9. A new criterion was added to determine when a conduit has
supercritical flow and therefore normal flow conditions
might apply. It is based on both water surface slope and
the Froude number (as opposed to just one or the other).
(See dynwave.c, project.c, keywords.c, enums.h, and text.h).
10. A Flow Instability Index is now computed for each non-pump link.
It counts the number of time steps in which the link's flow is
either higher or lower than the flows at the previous and next
time steps. The Status Report lists the links with the five
highest indexes. (See objects.h, stats.c, and report.c).
11. Node volumes are now initialized to take account of any initial
ponding that may be implied by the node depth stored in a hot
start file (see flowrout.c).
12. The area corrections to the inlet and outlet loss terms under
dynamic wave flow routing that were introduced in Build 5.0.008
were removed (see dynwave.c).
13. To comply more closely with standard hydraulic practice, the
head across an orifice is now computed with respect to the
midpoint of its opening, rather than to the bottom. Also,
orifices are now treated the same as weirs in terms of not
contributing any surface area to their end nodes (see link.c
14. The partly opened setting for an orifice is now interpreted as
fraction of the full orifice opening height available rather
than as the fraction of the full area available. Also, the
equivalent discharge coefficient for a partly full orifice is
now re-computed whenever the setting of the orifice changes
15. In kinematic wave flow routing, when a conduit's inflow is
limited to its maximum normal flow, its corresponding inflow
area is now correctly normalized to the full flow area (see
16. For dynamic wave flow routing, the criteria used to check if
a node is not full before using its depth to compute a variable
time step was corrected to avoid excessively small time steps
17. The width v. depth table for circular shapes was expanded to 51
entries to match that of the other tables for this shape (see
18. The number of entries in the geometry tables for irregular
cross-sections was increased to 51 entries (see objects.h).
19. For Divider nodes, both end nodes of the diversion link are now
checked to see if one of them is connected to the divider node
20. Conditions on Outlet links are now correctly recognized in control
rule statements and an error message is now generated if more than
one rule clause is placed on the same line (see controls.c).
21. When the Ignore Rainfall option is used, a rain gage's rainfall is
now properly initialized to 0 to prevent a spurious rainfall value
from being reported (see gage.c).
22. An explicit check is now made in the engine (which already exists
in the GUI) to see if the ID name of the outlet of a subcatchment
exists as both a node and a subcatchment. If so, then Error 108
is thrown. (See subcatch.c).
23. The column in the Node Depth Summary of the Status Report that
previously displayed the total volume of ponded water at each
node (but was labelled "Total Flooding") now displays the maximum
volume of ponded water at each node and is labelled "Max Vol. Ponded".
Also, flow values appearing in the Status Report's tables were expanded
to 3 decimal places for MGD and CMS units, and an additional
decimal place was added to ponded area and conduit length in the
report's Input Summary tables (see stats.c and report.c).
24. When a node is ponded under dynamic wave routing, the water depth
is now always set equal to the ponded depth rather than the smaller
of the ponded and dynamic depths (see dynwave.c).
25. A more efficient way of processing the mathematical expressions
used in treatment functions has been implemented (see mathexpr.h,
mathexpr.c, and objects.h).
26. A bug in the Groundwater routine that allowed infiltration to
continue even when the entire groundwater table was saturated was
fixed as was a metric units conversion error on computed groundwater
flow (see gwater.c).
27. The locations of the left and right overbank stations for an
irregular channel transect are now adjusted by the Station Modifier
multiplier, in the same way as all of the other station locations
across the transect are.
28. An error in computing the flow contribution of the triangular
ends of a trapezoidal weir was corrected (see link.c).
29. A roundoff error under kinematic wave and steady flow routing that
sometimes caused nodes to be incorrectly reported as ponded was
fixed (see flowrout.c).
1. A "Tools" item was added to SWMM's main menu. The existing menu
options to set Program Preferences and Map Display Options were
moved there. In addition, it contains a "Configure Tools" option
that can be used register add-in tools with SWMM 5. Consult the
Users Manual or the Help file for more information regarding add-
2. A "None" option was added to the choice of routing methods on the
General page of the Simulation Options dialog to accommodate the
new No Routing analysis option.
3. The Property Editor for Pumps was modified to allow the Pump Curve
field to remain blank (or accept a *) to signify the new Ideal type
pump and to accept startup and shutoff depths.
4. The Property Editor for orifices was modified to include a Time To
5. The Unit Hydrograph Editor dialog was modified to include the new
Initial Abstraction parameters.
6. The Analysis Options dialog was modified to accommodate the new
supercritical flow criterion.
7. The Cross-Section Editor and the Curve Editor were modified to
accommodate the new Custom cross-section shape feature as well as
the new Circular Force Main shape.
8. The File | Export menu has a new option that, once a run has been
successfully made, will export the node and link results at the
current time period being viewed to a Hotstart file.
9. The popup menu for toggling the map's Auto-Length feature was
replaced with a check box on the Status Panel.
10. A check box was added to the Map Dimensions dialog to ask if conduit
lengths and subcatchment areas should be recomputed when the Auto-
Length setting is on.
11. The Group Delete feature now offers the option of only deleting
objects with a specific value for their Tag property.
12. Ponded Area was added to the list of node parameters that can be
assigned a default value through the Project >> Defaults menu item.
13. The epaswmm5.ini file that contains a user's program preferences
is now saved to the users Application Data folder, in a sub-folder
named EPASWMM, rather than to the user's home folder.
14. Conduit slopes are no longer displayed as absolute values, so that
negative slopes will show up on a thematic display on the study area
map and will also be identified when a map query is made.
15. The bitmap image on the Run speed button was replaced.
16. The automatic identification of a connected path of links between
two nodes specified on the Profile Plot dialog now uses the path
with the smallest number of links.
17. The Study Area Map's Zoom Out feature no longer uses a zoom out
to previous extent. Instead it zooms out relative to the current
center of the map.
18. The Animator toolbar was made a permanent part of the Map Browser
19. The operation of the date and time controls on the Map Browser panel
were modified to work correctly with reporting times that are larger
than 1 day.
20. The options on the Map Query dialog were extended to allow one to
identify all nodes on the map that have been assigned a particular
type of external inflow (Direct, Dry Weather, RDII, or Groundwater).
Build 5.0.009 (9/19/06)
1. A climate file in the user-prepared format will no longer
be confused with one using the Canadian format (see
2. The minimum runoff which can generate pollutant washoff was
changed from 0.001 in/hr to 0.001 cfs (see subcatch.c).
3. A new RDII event now begins when the duration of a
continuous run of dry weather exceeds the base time of
the longest unit hydrograph rather than arbitrarily being
set at 12 hours (see rdii.c).
4. Problems with dynamic flow routing through long force mains
connected to Type 3 and Type 4 pumps have been corrected (see
dynwave.c and link.c).
1. A problem in displaying profile plots when all elevations
are below zero has been corrected.
Build 5.0.008 (7/5/06)
1. The conversion from the Horton infiltration drying
time input parameter to an equivalent regeneration
curve constant was corrected.
2. Pipe invert elevations at outfalls are now measured
relative to the outfall stage elevation rather than
the outfall's invert elevation.
3. Entrance/exit minor loss terms for dynamic wave flow
routing are now adjusted by the ratio of the mid-point
to entrance/exit areas to improve the energy balance.
4. A possible error in computing flow depth from head when
checking the normal flow limitation based on the Froude
number for dynamic wave flow routing was corrected.
5. A potential problem with converting the units of rainfall
read from an external file was corrected.
6. The equivalent length of orifices and weirs was changed
from being a minimum of 200 ft to a maximum of 200 ft.
7. Problems in displaying washoff mass balance results for
pollutants expressed as Counts/Liter were fixed.
8. The reporting of total system maximum runoff rate in the
Status Report's Subcatchment Runoff Summary table has been
9. The subcatchment pollutant washoff process was
reprogrammed to provide more rigorous mass balance
results for the case where runoff from one subcatchment
is routed over another subcatchment or when there is
direct deposition from rainfall.
10. Checks for non-negative conduit offsets and orifice/
weir/outlet heights have been added.
11. A constant value and a scaling factor have been added to
Direct External inflows. See the Inflows Editor - Direct
Page topic in the Help file for more details.
12. A listing of total washoff loads for each pollutant for
each subcatchment has been added to the Status Report.
13. A new summary table of Node Inflows and Flooding has been
added to the Status Report.
14. A new summary table of Outfall flows and pollutant loads
has been added to the Status Report.
15. The 5.0.006 Engine Update #12 has been revoked.
1. The Inflows Editor was modified to accommodate the baseline
and scaling parameters added to direct external inflows.
2. The .INI file that saves a user's program preferences is now
saved to the user's home directory rather than the SWMM
3. The Select All command was extended to apply to the Status
4. A new text file viewer component was used for the Status
Report to speed up the display of the report's contents.
5. A formating error on the Horizontal Axis page of the Graph
Options dialog form was corrected. This required making
changes to the custom Chart Dialog component that is included
with the GUI's source code.
6. Some cosmetic changes were made to the look of Tabular
7. Type 3 pump curves (head v. flow) are now displayed with
head on the vertical axis and flow on the horizontal axis
when the View option is selected in the Curve Editor dialog.
Build 5.0.007 (3/10/06)
1. An "Ignore Rainfall" analysis option was added that causes
the program to only consider user-supplied external inflow
time series and dry weather flows and ignore any rainfall
inputs that would otherwise produce runoff.
2. The hydraulic radius calculations for Rectangular-Closed,
Rectangular-Triangular, and Rectangular-Round conduit shapes
were modified to account for the increase in wetted perimeter
that occurs under full flow due to the top surface.
3. Refinements were made in several places in the code that need
to distinguish between Full Flow and Maximum Flow conditions in
4. The code now properly accounts for the case where the depth at
which the maximum normal flow occurs through an irregular shaped
cross section is less than the full depth.
5. The final volume of any ponded water (caused by node flooding)
is now included in the reported flow continuity error.
6. Peak runoff flow was added to the Subcatchment Summary table
in the Status Report.
7. Non-conduit links are now included in the Link Flow Summary table
of the Status Report.
1. The Maximum Depth field in the Property Editor for a conduit with
an irregular shape now shows the correct value for any set of
transect elevation values.
2. The "Save Profile to File" button is now enabled when the user
manually adds a specified set of links to the Profile Plot dialog.
3. Link Flow Depth and Link Velocity have been added as choices for
4. The way that non-conduit links are displayed on profile plots was
changed to avoid problems that occurred for weirs and orifices with
crest heights above the node invert.
5. A problem with the way that the Group Editing function was handling
the case of irregular shaped cross sections was fixed.
Build 5.0.006a (10/19/05)
1. The formula for snow melt rate during periods with rainfall
was corrected to return its value in ft/sec rather than in/hr.
2. A problem with generating routing interface files for systems
with just nodes and no links was corrected.
1. Numerical precision problems in computing centroids for
subcatchments with very small distances between vertices
2. A problem with no calibration data being shown on a time
series graph when some of the data were outside the range
of the graph was fixed.
3. A problem with calibration data represented as dates (not
elapsed time) being shifted one reporting period over in
time series graphs that used elapsed time was fixed.
Build 5.0.006 (9/5/05)
1. A new summary table of maximum volumes and outflow rates
for each storage unit has been added to the Status Report.
2. The SWMM 4 BC parameter, which specifies a minimum groundwater
table elevation for groundwater flow to occur, was added as an
optional groundwater flow parameter. If not provided then as
before, the invert of the receiving node defines the minimum
groundwater table elevation for flow to begin.
3. A new option was added to the Action clause of a control rule that
allows the control setting for pumps, orifices, weirs, and outlets
to be defined either by a curve (of setting versus node depth, for
example) or by a time series. See the "Modulated Controls" topic
in the Help file for more details.
4. The problem with interior nodes being mistaken for outfall nodes
(depending on the orientation of the connecting links) under water
quality analyses was fixed.
5. Geometry tables for standard size elliptical pipes were added
(the standard size code number in the input file was being mistaken
for an actual dimension).
6. Storage curves of area versus depth are now linearly extrapolated
when a depth exceeds the table limit (as in SWMM 4) rather than just
keeping the area constant.
7. Evaporation is no longer computed from a storage unit when it
8. In water quality routing, concentrations in storage units are now
adjusted to reflect any evaporation loss over each time step.
9. It is now permissible to use the same hotstart file to both provide
initial values for a run and to save the final values from a run.
10. The code was modified to be able to read evaporation values from a
climate file during runs where no runoff computations are being
made (previously any evaporation in such files was being ignored in
data sets with no subcatchments).
11. A problem in the way that water quality was being routed through
dummy conduits was fixed.
12. For pollutant treatment functions that define fractional removal in
a storage unit node as a function of concentration, the concentration
used is now the inflow concentration into the node (as is done for
non-storage nodes), rather than the concentration in the storage unit.
13. The global first-order decay reaction assigned to specific pollutants
is not applied to any storage unit that has a treatment function
defined for the pollutant.
14. The total moisture available for infiltration at each time step of
the runoff process now has evaporation subtracted from it before
infiltration is computed.
15. Corrections were made to the way that the water volume in the upper
soil zone is depeleted during dry periods under Green- Ampt
16. A climate file is now positioned to begin reading at the start of the
simulation period (rather than the start of the file) unless the user
supplies a specific starting date to begin reading from the file.
17. A fatal error is now generated if the end of a climate file is reached
when seeking climate data during a run (rather than just maintaining
the same climate values for the remainder of the run).
18. The Node and Conduit flow statistics that appear in the Status Report
are now only collected over the reporting period of the simulation,
not the entire period (as would be the case when the user specifies
a Report Start Date that comes after the Simulation Start Date).
19. The computation of the initial and final groundwater storage volumes
used in the Groundwater Continuity table were corrected. This error
only affected the continuity numbers and not the computed flows and
water table levels.
1. The File >> Reopen command will now list up to 10 most recently used
2. Map coordinates are now displayed with 3 decimal places in the Status
3. The File >> Preferences dialog now contains a "Prompt to Save Results"
option. If left unchecked, simulation results will always be saved when
a project file is closed and will be available for viewing the next
time the project is opened.
4. A "Report Elapsed Time by Default" option was also added to the File >>
Preferences dialog. If checked, then time series graphs and tables will
default to using elapsed time, rather than date/time, as the time
variable. This choice can always be changed in the dialog box that
appears when a graph or table is first created.
5. Additional reporting variables were added to the list of parameters
for which Calibration Files can be used (e.g., groundwater elevation,
node flooding, etc.).
6. Percent impervious was added to the list of subcatchment themes that
can be viewed on the Study Area Map.
7. An Exceedance Frequency plot panel was added to the output produced
when a Statistics report is generated.
8. Users can now add, delete, or re-position items in the list of
links selected for a Profile Plot in the Profile Plot dialog using a
new set of buttons added to the dialog. Links are added to the list
by selecting the link either on the Map or from the Data Browser and
then clicking the PLUS button on the dialog.
9. Profile Plots can now be generated before any simulation results are
available. They include an Update button that allows one to update
the plot after editing changes have been made to any nodes or links
contained in the plot.
10. The Edit >> Find menu command (and its associated speed button) was
split into two sub-commands, one for finding objects on the map (as
before) and another for finding text within a Status Report.
11. Problems with the wrong data fields sometimes being updated in the
Group Editor were fixed.
12. The Interface File Combine utility was not working at all (the format
of the interface file had changed since the original code was written).
This has been fixed.
13. The centroids of subcatchment polygons on the map are now computed as
true centroids rather than being merely the average of the vertex
14. The Maximum Depth property is now preserved when a storage unit is
converted to a junction (by right-clicking on it and selecting
Convert To from the popup menu).
15. Map and Profile Plot animation is now turned off whenever the Animator
Toolbar is closed.
16. More universal support was provided for entering numerical values in
scientific notation throughout the GUI's various data entry fields.
17. Display problems with zoom-ins on the preview plots of Transects,
Curves, and Time Series in their respective Editor dialogs were fixed.
18. In the GUI source code:
a. The custom TOpenTextFileDialog component was renamed to
TOpenTxtFileDialog so as not to conflict with a Delphi 2005
component of the same name.
b. The custom ChartDlg component was modified to add support for a
chart axis that uses Date/Time labels.
c. A new unit named Ucalib.pas was added that includes the code for
reading data from Calibration Files that was previously contained
in the Fgraph.pas unit.
d. The Delphi DFM files for the project are now packaged as text
files, not binaries, in the source code distribution.
Build 5.0.005b (6/15/05)
1. The end node offsets for conduits with the partly filled
circular cross-section shape were not being increased to
account for the depth of fill.
2. Flow through a weir was not necessarily zero when the
water level on the side of the weir at higher head was
3. The "crest height" for a Bottom Orifice is now
interpreted as having the orifice lie in a horizontal
plane the specified distance above its upstream node's
invert. This allows riser outlet pipes in storage units
to be simulated.
1. The keyword "WEIR" was not being recognized as a
legitimate type of Flow Divider node by the GUI's
input data file parser.
2. The Profile Plot could display hydraulic grade lines
that dropped below the invert of a conduit.
Build 5.0.005a (5/25/05)
1. An erroneous error message that appears when a node has
multiple outflow links with one of them being an Outlet
link has been fixed.
1. Corrections were made for the way a Profile Plot is
drawn when negative elevation values occur.
Build 5.0.005 (5/20/05)
1. An error in computing ponded depths at flooded nodes under
Dynamic Wave flow routing was corrected.
2. The wrong lookup function was being used to find water
elevations at Time Series type outfall nodes.
3. An error in interpolating values stored on a routing interface
file was corrected.
4. The rainfall file reader was confusing the standard space-
delimted format with other file formats.
5. A reporting error for rainfall time series that had no ending
zero value was corrected.
6. A problem with neglecting to compute a snowmelt coefficient
for pervious areas was fixed.
7. The keyword for specifying that pollutant buildup be normalized
to curb length was modified to accept either CURB or CURBLENGTH.
8. The conversion factor the user supplies for external pollutant
mass inflows must now convert time series values into mass
concentration units per second (e.g., 5.25 will convert from lbs/
day to mg/sec). Flow units are no longer part of the conversion.
9. The ratio of maximum to design flow listed for each conduit in
the status report was corrected to account for the number of
barrels included in the conduit.
10. The minimum elevation change applied to a flat conduit was
changed to 0.001 feet, as used in SWMM 4.
11. The maximum depth of an irregular cross-section transect is now
based on the highest elevation of all stations, rather than just
the higher of the first and last station, and vertical walls
extending up to the higest elevation are added at the first and
last station if need be.
12. The nominal width property of an irregular cross-section transect
is now taken as the top width at full depth rather than the
maximum width over all depths.
13. At outfalls where the user-specified water elevation is below
that of a free outfall, the free outfall elevation is now used.
14. A new property, the maximum allowable flow, was added to the
Conduit object. The default value is 0.0, which indicates that
no maxmimum flow is prescribed.
15. Depths at outfall nodes under Steady and Kinematic Wave flow
routing are now reported as the depth in the connecting
16. The calculation of the head over a non-surcharged, submerged weir
was corrected to be based on the height of water above the weir
crest, rather than the difference in heads on either side of the
17. The equation used to reduce the length of a weir with side
contractions was modified to fix a bug in SWMM 4.
18. A new water quality routing algorithm was written that produces
more robust results under Dynamic Wave flow routing.
19. The Compatibility Mode option under Dynamic Wave flow routing was
removed. Now there is just a single method used which has been
designed to be compatible with SWMM 4 yet produce more stable
20. A new dynamic wave routing option was added that determines which
criterion decides when conduit flow is limited to normal flow (it
represents the KSUPER parameter used in SWMM 4).
21. A new flow routing option was added that allows routing calculations
to be skipped during periods of steady flow which can greatly reduce
the time required for continuous simulations.
1. An error in reading the flapgate parameter for Weirs in an input
file was corrected.
2. Having the Property Editor positioned outside the viewable screen
area when the user changed the video settings to a lower resolution
3. The Convert To option to change nodes from one type of object to
another was fixed.
4. The Routing Time Step option is now entered as fractional seconds
on the Analysis Options form. The older format of hrs:min:sec will
still be imported correctly from previous SWMM5 input files.
5. The ability to include a startup input file on the command line
that launches the GUI was added (add /f filename to the command
line where filename is the fully qualified name of the input file
to start with).
6. Support for output results files greater than 2 gigabytes was added.
7. The display of the hydraulic grade line in Profile Plots, and its
intersection with the flow volume in conduits was improved.
8. The summary results tables contained in the Status Report were
modified to display more useful information.
9. The graph options selection dialogs were made to behave more
10. Support was added for copying and printing the graphical views of
curves, time series, and transects from within their respective
11. The SWMM 4 flow calibration data file (Extran1.dat) distributed with
the example data set Example2.inp was modified to contain the flows
actually produced by SWMM version 4.4h, rather than the original
numbers printed in the 1988 Extran manual.
In addition, the SWMM 5.0 Users Manual and Help file were updated to
reflect these changes and new additions.
Build 5.0.004 (11/24/04)
1. Fixes were made to the routines that identify and read data from the
NCDC-formatted external rain files.
2. The sign of reported velocity in links with adverse slope was
3. Reading of results from previously saved Runoff Interface files
4. The calculation of a regeneration rate constant from a soil drying
time value for Curve Number infiltration was corrected, and the
method was modified to use a constant infiltration capacity during
each rain event, rather than a continuously declining capacity.
5. A correction was made to the dynamic wave routing routine for
SWMM4 and SWMM3 compatibility modes that improves the match with
Extran results from these earlier versions of SWMM.
6. The check for zero-sloped conduits was modified to include any
conduit with elevation difference below 0.01 feet.
7. The computation of the ponded depth at flooded nodes under dynamic
wave flow routing was corrected.
8. A check was added to make sure that the reporting time step is
not longer than the run duration.
9. Surcharged and high Froude number conduits were previously excluded
from consideration when computing a variable time step for dynamic
wave routing; they are now included.
10. The code numbers for the concentration units used for each pollutant
was added to the binary output file produced from a simulation.
1. Negative values can now be entered for temperature values that
appear on several input forms.
2. The input file reader now checks to make sure that the various time-
of-day option values are valid.
3. A problem with copying the correct dates for a Tabular Report that
is being copied to the clipboard or to a file was corrected.
4. The Graph Options dialog form was modified to display the Solid
option for Style whenever a Size greater than 1 is selected. (Due
to a limitation of the Graphics library used in EPA SWMM, only
solid lines can be drawn at a thickness greater than 1.)
Build 5.0.003 (11/10/04)
1. Modifications were made to full depth entries of width tables for
closed rounded cross-section shapes to improve the numerical
stability for dynamic wave flow routing.
2. Error 405 was added to detect if the size of the binary results
file would exceed the 2.1 Gbyte system limit.
3. A units problem for RDII inflows under metric flow units was
4. A problem reading the TEMPDIR option when it contained spaces was
5. Support for Canadian DLY02 and DLY04 temperature files was added.
6. Rule-based control of crest height for weirs was corrected
(previously the control setting adjusted flow rather than the
relative distance between weir crest and crown).
1. A problem with the Group Editing feature for conduits was corrected
(the editor would update the wrong conduit parameter).
2. Execution time for long term simulations on smaller projects was
speeded up considerably by only refreshing the progress meter every
day rather than every minute.
3. The time to draw time series graphs and perform statistical analyses
on large data sets was considerably shortened.
Build 5.0.002 (11/1/04)
1. Modifications made to the Picard method used for dynamic wave
flow routing routine.
Build 5.0.001 (10/29/04)
First official release of SWMM 5.
Source: epaswmm5_updates.txt (list of SWMM5.0 bug fixes and updates).