SWMM 5.1 Update History Or Key Changes
Build 5.1.002 ----------------------- Engine Updates: 1. A bug that prevented hotstart files with the latest format from being read was fixed. 2. Only non-ponded surface area is saved for use in the dynamic wave surcharge algorithm (when water depth is close to the node's crown elevation). GUI Updates: 1. Creation of auxilary forms on startup was moved from the main form's OnActivate event to its OnCreate event, while creation of the map form was moved tothe OnShow event. 2. The routines for saving and reading the main form's position and size in the swmm5 .ini file were modified. 3. A memory leak related to copying cells from the grid editor used in various dialogs was fixed.-----------------------
1. SWMM can now read the new file format for precipitation
data retrieved online from NOAA-NCDC.
2. A new choice of infiltration method, the Modified Horton
method, has been added. This method uses the cumulative
infiltration in excess of the minimum rate as its state
variable (instead of time along the Horton curve),
providing a more accurate infiltration estimate when
low rainfall intensities occur.
3. RDII interface files created internally by SWMM are now
saved in a binary format to reduce storage space. The ASCII
text format for these files is still supported for users
that find it desireable to create the files outside of SWMM.
4. Two new categories of LID controls, one for Green Roofs and
another for Rain Gardens, have been added so they no longer
have to be configured from the Bio-Retention Cell control
(although that option still remains). The Green Roof uses
a new Drainage Mat layer to store and convey the water that
percolates through the soil layer.
5. Users can now add their own groundwater outflow equation to
a subcatchment, to be used in place of or in addition to the
standard equation. Similar to treatment functions, the equation
can be any mathematical expression that uses the same ground-
water variables that appear in the standard equation.
6. Evaporation of water from open channels has been added.
7. A new conduit property named Seepage Rate (in/hr or mm/hr)
has been added to model uniform seepage along the bottom
and sloped sides of a conduit.
8. Infiltration from storage units is now referred to as
seepage, to be consistent with seepage from conduits. The
only required parameter is a seepage rate (in/hr or mm/hr).
Previous data files that supply a set of Green-Ampt
infiltration parameters will still be recognized.
9. Separate accounting and reporting of evaporation and
seepage losses in storage units is now made.
10. Open rectangular channels now have a new parameter that
specifies if one or both side wall surfaces should be
ignored when computing a hydraulic radius (to provide
improved support for quasi-2D modeling of wide channels
and overland flooding).
11. New Dynamic Wave Analysis options have been added for
the maximum number of iterations and head tolerance used
at each time step. The percentage of time steps where
convergence is not achieved is also now reported.
12. Users can now set the flow tolerances that determine if
flow routing calculations can be skipped because steady
state conditions hold.
13. Control rules can now use a conduit's OPEN/CLOSED status
in both premise conditions and action clauses.
14. The meaning of the link view variable "Capacity" has been
changed. For conduits it is now the fraction of the full
cross section area filled by the flow, while it is the
control setting for all other types of links (the meaning
of the control setting varies by link type -- see the Help
file or the Users Manual).
15. The link Froude number view variable has been replaced with
the link's flow volume, the subcatchment Losses variable has
been replaced by two new variables - Evaporation and
Infiltration, and upper groundwater zone Soil Moisture has
been added as a new view variable.
16. The Node Inflows Summary table of the Status Report now
includes a new column that lists the mass balance error
in volume units for each node.
17. A new summary table, Link Pollutant Load, has been added
that displays the total mass load of each pollutant that
flows through each link.
18. Using a Drain Delay time of 0 for Rain Barrel LIDs now means
that the barrel is allowed to drain continuously, even as it
is filling during wet weather periods.
19. The requirement that an impervious surface must be dry
(have no more than 0.05 inches of standing water) before
it could be subjected to street sweeping has been dropped.
20. After runoff ceases and a land surface goes dry due to
evaporation, any remaining mass of pollutant originating
from direct deposition or upstream runon is assumed to be
unavailabe for future washoff (it shows up as Remaining
Buildup in the mass balance report).
21. The way that wet weather washoff inflow loads are
interpolated across a flow routing time step was modified
to produce a better match between the reported total runoff
load and total quality routing inflow load.
22. The method used to select a time step for processing RDII
unit hydrographs was modified to consider the case where
K (the ratio of rising limb to falling limb duration) is
23. When the moisture content of the upper groundwater zone
reaches saturation, the depth of the lower saturated zone
is now set equal to the full aquifer depth (minus a small
24. Conduits with negative slopes whose absolute value is
below the Minimum Slope option will have their slope
changed to the positive minimum value, thus allowing
them to be analyzed using the Steady Flow and Kinematic
Wave routing options.
25. The Avg. Froude Number and Avg. Flow Change columns in the
Flow Classification Summary table have been replaced with the
fraction of time steps that flow is limited to normal flow
and the fraction of time steps that flow is inlet controlled
26. An error condition now occurs if a pump's startup depth
is less than its shutoff depth.
27. Only the upstream node for orifice and weir links is now
checked to see if its maximum depth needs to be increased
to meet the top elevation of the orifice or weir opening.
28. Weirs are no longer allowed to operate as an orifice when
they surcharge. Instead any excess flow will flood the
29. A warning message is now written to the Status Report if
the crest elevation of a regulator link is below its
downstream node's invert.
30. When a reporting time falls in between a computational time
step during which a pump's on/off status changes, the reported
pump flow is the value at either the start or end of the time
step depending on which is closer to the reporting time (i.e.,
no interpolation is used).
31. Control rule conditions can now accept elapsed time or
time of day values as decimal hours in addition to hours:
32. The test for a control rule condition equaling a specified
elapsed time or time of day was modified to more accurately
capture its occurrence.
33. If the Water Quality analysis option is disabled then the
binary results file no longer contains any pollutant values
(of 0) for all time periods.
34. Hot Start files now contain the complete state of the watershed
and conveyance system, so that future simulations can start up
correctly where they left off.
35. The following changes to error reporting were made:
- Error 319 was re-numbered to 320 and a new Error 319
was added for a rainfall data file with unknown format.
- Format errors in external time series files are now
listed as Error 363 (invalid data) instead of Error
173 (time series out of sequence).
36. Warning messages written to the Status Report are now
single spaced instead of double spaced. See report.c.
37. The Link Summary table in the Status Report now lists conduits
with negative slopes in their original orientation instead of
in their reversed state.
38. A refactoring bug from 5.0.022 that prevented snowmelt
from infiltrating has been fixed.
39. Snowmelt rate during rainfall conditions and the updating
of the antecedent temperature index were were not being
converted from the six hour time interval used in Anderson's
original NWS snowmelt model to the hourly basis used in SWMM.
40. A refactoring bug that failed to set the maximum number of
characters high enough for a line read from a user-prepared
rainfall data file has been fixed.
41. The optional Maximum Volume parameter for Horton
infiltration was not allowing any recovery of infiltration
capacity between storm events.
42. Evaporation from the lower groundwater zone was being
computed from the rate remaining after surface and upper
zone evaporation was considered instead of from the
unadjusted rate (with a reduction afterwards if it exceeds
the remaining available rate).
43. An error in applying the Vegetation Volume Fraction parameter
to swales was corrected.
44. The time from the last rainfall used to determine when a
Rain Barrel should begin to empty wasn't being computed
45. An erroneous error message for Rain Barrel LIDs with a
zero Void Ratio has been fixed (the Void Ratio parameter
should be ignored for Rain Barrels).
46. The display of extraneous infiltration results in detailed
reports for Rain Barrel LIDs has been eliminated.
47. The check on no street sweeping for a subcatchment during
wet periods was checking rainfall over the entire study
area instead of just the subcatchment.
48. An erroneous warning message regarding negative offsets for
pumps when elevation offsets are used has been eliminated.
49. A possible divide by zero error for trapezoidal channels
with zero bottom width has been eliminated.
50. A program crash that occurred when the Ignore Routing
option was selected and results were to be saved to a
Routing Interface file has been fixed.
51. Projects that had no subcatchments or had the Ignore
Runoff switch selected were not able to evaporate water
from storage units.
52. Weekday and weekend hourly time patterns for Dry Weather
inflows are now correctly applied in a mutually exclusive
53. The Node Flooding Summary table in the Status Report now
correctly lists the peak depth of ponded water above the
node's maximum depth (i.e., its rim or ground elevation)
instead of above its invert elevation.
54. Occasional problems caused by the date/time functions not
returning an hour between 0 and 23 (for hourly time patterns)
and being off by 1 second (when writing results to outflow
interface files) have been fixed.
55. A bug introduced in release 5.0.017 that caused the
concentration after first-order decay in a storage node to
be ignored has been fixed.
56. A bug in the Total Elapsed Time listed at the end of the
Status Report for runs taking longer than 24 hours of
computer time was fixed.
57. A correction was made for the slope correction factor used
for mitered culvert inlets.
58. The procedure for finding the surface area of a storage unit
given its volume was corrected for the case where the
storage curve has a section of decreasing area with depth.
59. The procedure for finding a cross-section area given a
section factor value was corrected for the case where the
section factor table does not have its highest value as
the last entry in the table.
60. An error in computing the hydraulic radius of the Rectangular-
Triangular conduit shape as a function of flow depth was
1. The entire GUI code was ported from Delphi 7 into Delphi XE2.
2. Different color themes for the user interface can be
selected from the Program Preferences dialog.
3. The "Data" Browser panel is now named as the "Project"
4. The Object Toolbar has been eliminated. Visual objects
are now added to the map in the same manner as non-visual
objects -- by selecting their category from the Project
Browser and then clicking the Browser's "+" button (or
by selecting Project | Add... on the main menu).
5. The LID Control and LID Usage editors were re-designed to
accomodate the new LID control options.
6. Modifications were made to accept the new engine features
mentioned above (modified Horton infiltration, seepage rate
parameter for conduits, side wall option for rectangular
channels, and the additional Dynamic Wave routing options).
7. Modifications were made to accept the updated set of output
8. The summary results tables that used to appear as part of the
Status Report have been moved into a separate Summary Report
that makes it easier to view and sort them.
9. The Time Series Plot selection dialog was modified to allow
more than one kind of object/variable pair to be plotted.
10. The Graph Options dialog was modified to allow a vertical
axis to be inverted (as when plotting an inverted rainfall
hyetograph on the same graph as a runoff hydrograph).
11. The option to compute evaporation using the Hargreaves
equation wasn't being saved along with the rest of a project.
12. If pollutants are defined for a project but the Water Quality
analysis option is not selected, then after a new analysis is
made pollutants will no longer be listed as theme variables in
the Map Browser nor will they be available for graphs, tables
or statistical reports.
13. The columns for the [XSECTIONS] section of a saved project
file now includes a heading label for "Culvert Code".