1D diagnostics messages

Message

Description

E1003

Berlos - no. of data sets must not be > 30 or < 1

The number of Bernoulli Loss data sets (stage, area, loss value) must be between 1 and 30

E1004

'Unit' data error at line 'l'

• An error has been detected in 'unit' at line number 'l'. Possible causes include:
• The number of data sets does not equal the specified number in the above unit;
• A tab has been included in a data field;
• A decimal place is included in an integer field;
• Character type data in a numeric type field (check 'o', 'l', 'z');
• Unexpected increase or decrease in tabulated values (e.g. time decreasing in HTBDY data);
• Number of data fields detected not as stated in the documentation (i.e. missing data);
• INITIAL CONDITIONS omitted from the datafile.

E1005

'Unit' unit unacceptable as first data unit - 'unit' data error at line 'l'

A 'unit' is not allowed as the first unit in a datafile.

E1006

'Unit' - no. of stage/gate opening datasets < 2 - 'unit' data error at line 'l'

A minimum of 2 pairs of stage and gate opening data are necessary in unit 'unit'.

E1007

'Unit' - maximum no of gates is x - 'unit' data error at line 'l'

A maximum of 50 gates is allowed in a single vertical sluice unit, or 100 for a radial gate unit.

E1008

Maximum number of nodes is exceeded

The maximum number of nodes for the licence of Flood Modeller has been exceeded. Contact Flood Modeller Support to upgrade your licence.

E1009

Maximum number of units is exceeded

The maximum number of units for the licence of Flood Modeller has been exceeded. Contact Flood Modeller Support to upgrade your licence.

E1011

Unidentified unit with type = 'x'. data error at line 'l'

This indicates a possible typing error with a unit type identifier at line 'l'. Also check that for the preceding unit the number of data sets is equal to the number specified.

E1013

The EGGFORM option is not yet available,try using a CIRCULAR conduit with a suitable diameter

Eggform conduits are not permitted.

E1014

Supercritical flow between 'label1' and 'label2'. You should use the option for dealing with Froude numbers greater than 1

Supercritical flow has been detected - see the General System Parameters topic for how to use the supercritical flow option.

E1017

Negative flow at 'label' - the direct method cannot handle backflow over structures yet.

During iterations the direct steady state method has calculated backflow over a structure.  If backflow is not physically realistic then the error may be avoided by changing the flow splits in the initial conditions.  Otherwise use the pseudo time stepping steady state method.

E1018

Maximum no. of iterations exceeded, error = 'x'% , fw='y', label = 'label'

The direct steady state method was unable to solve the equations at the structure at 'label'.  The error may be avoided by changing the initial conditions, reviewing the structure data or by using the pseudo time stepping steady state method.

E1019

No solution on 'unit' 'label'

The direct steady state method was unable to solve the equations at the structure at 'label'.  The error may be avoided by changing the initial conditions, reviewing the structure data or by using the pseudo time stepping steady state method.

E1020

Water level exceeded maximum section data level dflood ( X.00m)
 Check model, extend section data or increase dflood

This error message most likely appears at the start of the simulation (i.e. straight away after the crash) and suggests that the initial conditions need improving.

The user can look into extending section data and increasing dflood parameter, but if these operations are not successful or are not practical, then the following can be carried out:

- increase the minimum flow of the model;

- incrementally build the model and generate the initial conditions as you progress (this would also help to identify any troublesome areas of the model);

-run the model in steady state to generate the initial conditions.

If there are a number of structures or junctions in the model, then the recommendation could be to manually add an initial estimate of the split of the flows (For example, if there is a bride unit and a spill, 100% of the flow can be assigned to the bridge).

E1022

Not a recognised type number. The type number given is as follows: - 'x'

Please Contact Flood Modeller Support with full details of the problem

E1022

Error writing OTTA file

Do not select the 'Write Otta File' option.

E1023

ERROR in unit type 'unit' which is attached to the following labels:- 'label1'  'label2'  

Specifies the unit type and labels for the preceding error message. Error details are provided in the preceding error message.

E1027

Error at line 'l' value of rsmd should not be less than 10

FSR parameter RSMD (residual soil moisture deficit) must be greater than or equal to 10

E1028

Error at line 'l' wrong number of unit hydrograph ordinates. Max number of allowed ordinates is

For a user specified unit hydrograph, the maximum number of ordinates is 1000. Also, check that it is positive.

E1029

Error - data interval too small for unit hydrograph calculation or Time to Peak too large.

The number of unit hydrogrpah ordinates calculated (Tb/dt) exceeded 1000 - either the time base of the unit hydrograph is too large or the data interval is too small.

E1033

Incorrect percentage runoff code of 'x' in subroutine prcal

This indicates an error in setting Percentage Runoff (PR) flag or data for hydrological boundaries - check input data.

E1036

Storm return period of 'x' too small to estimate rainfall depth. Minimum allowed is 2 years.

Storm return period must be at least 2-year for FSR and 1-year for FEH boundaries.

E1038

Areal reduction factor equation very inaccurate for durations less than half an hour.

A storm duration of at least half an hour is required for ARF calculations.

E1039

Water level below invert. label(node) = 'label'('n'); water level = 'x'

This indicates poor initial conditions, a data error or the onset of an instability.

E1042

HTBDY - No of data pairs must be > 1

Make sure that at least one H:T pair has been specified in the boundary.

E1044

Previous unit was not a RIVER or CONDUIT

The units immediately upstream and downstream of an INTERPOLATED section must be rivers or conduits (not a mixture).

E1045

It is not allowed to have interpolated sections between the following sort of geometrical conduits: Rectangular, Circular, Sprungarch, Fullarch. You should use REPLICATE instead of INTERPOLATE Labels involved: 'label1'   'label2'

Regular-shaped (geometric) conduits may not be INTERPOLATED, but can be REPLICATED.

E1046

You must have a RIVER or CONDUIT downstream of INTERPOLATED sections

The units immediately upstream and downstream of an INTERPOLATED section must be rivers or conduits (not a mixture).

E1051

Format error in numerical data. junco data error at line

Check for typing errors in the junction labels at the line specified.

E1056

The direct method cannot be used with automatic controllers

The control module may not be used with the direct method - use logical rules (in MANUAL mode) for control, or pseudo-timestepping for steady-state runs.

E1057

Number of errors found in node labels is 'x'.

This message gives the total number of errors found following the network check. A description of the errors and the labels involved is displayed prior to this message. Possible causes of the errors include:

• Not obeying the labelling rules given in the documentation (e.g. labels existing not asscioated with two units; rivers not connected correctly);
• Incorrectly typed labels;
• Tabs in-between labels;
• Labels not left-justified in field widths of 12 (or 8 for old data files), or a mixture of the two;
• A steady results file has been used to provide initial conditions but the node labels have been altered;
• Incorrect node count on line 2 of the data file;
• Initial conditions section (separate file, or part of the of the dat file) is not complete, or contains too many labels.

E1065

Variable outside linearization range with range 'x1' to 'xn' variable = 'x'

The range of the data ('x1' to 'x') within the specified unit needs to be increased to include the current value of the variable 'x'. This message may also indicate the onset of instability if the value of 'x' is unrealistic. However, extending the range may be sufficient to overcome a temporary instability (e.g. allowing negative flow in a QHBDY).

E1066

Variable outside interpolation range. 'x'set range = 'x1'  'xn', X point = 'x' incr = 'y1', nend = 'y2', nset = 'y3'

The range of the data ('x1' to 'x') within the specified unit needs to be increased to include the current value of the variable 'x'. This message may also indicate the onset of instability if the value of 'x' is unrealistic. However, extending the range may be sufficient to overcome a temporary instability (e.g. adding a Preissmann slot or increasing dflood).

E1072

rn must be greater than 1

The index (exponent) of head in the weir equation (user-input for general and notional weirs) must be greater than unity.

E1073

cd outside allowed range

The coefficient of discharge (user-input for general and notional weirs) must be greater than zero and less than 3.

E1074

cv outside allowed range

The coefficient of velocity must be greater than unity for a notional weir.

E1075

Weir breadth must be positive.

The breadth of the weir must be greater than zero.

E1079

Maximum no. of network iterations exceeded

The direct steady state solver was unable to solve the network in the specified number of iterations (default 25). A solution may be obtainable by improving the flow split estimates in the initial conditions or by using the pseudo time stepping steady method. The direct method temporary results are available by selecting this option from the Diagnostics tab on the 1D Simulation interface, and provide information of possible problem units; this also produces intermediate initial conditions in the zzd file which may also be imported and used as alternative splits. The number of direct method iterations can also be increased via the Backward compatibility tab on the 1D simulation interface, although it is unusual for a simulation to acheive convergence after more than 25 iterations.

E1080

Number of data points is less than 2. 'unit' - data error in line 'l'

A minimum of 2 data sets are required to define the river, bridge or conduit section or rainfall boundary data.

E1081

Number of data points is greater than 'x'. Data error in line 'l'

A maximum of 400 data sets are allowed for defining the river, bridge or conduit section.

E1091

FULL ARCH CONDUIT. The height of the crown can never be greater than half of the width. Check your datafile please.

A conduit arch takes the form of a section of a circle; therefore, its maximum height is restricted to half its width.

E1094

Reverse flows not valid in syphon spillways

Check that the downstream head can not realistically exceed the upstream head; if not, check the model schematisation, or an instability may be occurring. If it can, then consider an alternative way to model the situation.

E1095

Error at line 'l': decreasing cross section distance

The cross chainage data for a river section must not be less than that of the data line above (overhangs are not allowed)

E1096

Error above line 'l': panel contains zero and non-zero Manning's n

Panels (those parts of the section separated by '*'s) must not contain a mixture of zero and non-zero 'n' values. Check the data for the RIVER SECTION which includes line 'l'.

E1097

Error above line 'l': cross-section contains all zero Manning's n

All the 'n' values in the section are zero (zero conveyance) - this is not allowed.

E1098

Number of height points is greater than 'x'.

The maximum number of data points (400) + inserted extra points allowed for defining the river, bridge or conduit section has been exceeded.

Message

Description

E1100

Model is diverging. No solution has been found with the current time step. You should try decreasing the time step or improving the initial conditions

A very large (>10^16) matrix coefficient has been found - this indicates the onset of an instability. This is the earliest unit within the data file at which this error has been found - the source of the instability may be at this unit, or nearby.

E1105

No data in 'unit' at line LINE before 'x' hrs

Model start time is before the first time specified in the time series for this unit. Extend the time data to cover the required run length.  Check that the number of data sets is equal to that specified (n1).

E1106

No data in 'unit' at line LINE after 'x' hrs

Model end time is after the last time specified in the time series for this unit. Extend the time data to cover the required run length or use EXTEND or REPEAT flags.  Check that the number of data sets is equal to that specified (n1).

E1108

Tolerance for the direct method cannot be negative

A negative direct method tolerance has been specified in the datafile (General System Parameters) or 1D Simulation interface (Parameters tab).

E1109

Tolerance for the direct method cannot be greater than 0.1

A direct method tolerance greater than the maximum of 0.1 has been specified in the datafile (General System Parameters) or 1D Simulation interface (Parameters tab).

E1111

None of the labels in the initial conditions have been tagged.  Add a 'y' in the initial conditions section (column 14 [or 10 for old files] of the initial conditions section via a text editor) to indicate at which labels results are required.

None of the labels in the initial conditions have been tagged. Add a 'y' in column 10 of the initial conditions to indicate at which labels results are required.

E1112

Number of labels in initial conditions = 'x'. number of labels in data file at line 2 = 'y'

The number of labels in the initial conditions does not equal the number specified in line 2 of the General System Parameters.  If the cause of this error is not apparent then set the number of labels equal to those in the initial conditions and reply 'y' to the 'network check' prompt to obtain details of the labels involved. This error will also occur if the steady results file has been used to provide the initial conditions and the node labels have been changed following the earlier run.

E1113

Data error at line 'l'

An error has been detected in line 'l' of the initial conditions.  Check for non-numerical data after column 14 (10 for old files) of the initial conditions.

E1114

Data error in zzs file at line

An error has been detected in line 'l' of the '.zzs' file which is being used to provide initial conditions.  Check for non-numerical data after column 14 (10 for old files) in the steady state results. If the data reads '**********', this indicates the calculated value was out of range.

E1115

Data error at line

Check the data file for bad data (e.g. tabs and non-numerical data where numerical data is expected). Consult the Data Fields section in the Help for the unit in question for the expected format.

E1117

Data error at line 'l'. lower Froude Number greater or equal to higher value

The higher Froude number specified (Parameters tab on the 1D Simulation interface, or line 2 of the General System Parameters) must be equal to or greater than the specified lower Froude number. The convective acceleration term in the momentum equation is altered between these two values when approaching critical flow.

E1118

Error in reader

Check that the number of nodes in the model is neither greater than the maximum licence allowed of 1000 nor negative. A premature end of file will also generate this error.

E1119

Previous unit was not a RIVER or CONDUIT

A replicate unit must be preceded by a river or conduit unit.

E1120

REPLICATE/INTERPOLATE must be preceded by a RIVER or REPLICATE with a positive chainage

The replicated or interpolated unit indicated followed a channel unit with zero chainage. This is not allowed - this unit is now at the beginning of a reach and there is nothing to replicate or interpolate. In the absence of any other data, you may choose to copy the section data from the section immediately upstream.

E1121

There is a spill label assigned to the last river unit in a reach. This is not allowed

A spill applies between the section to which it is attached, and the next section downstream. In this case, there is no downstream section.

E1123

Unit type may not be connected to reservoir at label 'l'

A reservoir is connected to another reservoir, junction or RNDSC - this is not allowed. Put a BERNOULLI LOSS, SPILL or RIVER/CONDUIT between the units as appropriate.

E1128

You must have at least two consecutive RIVERs or CONDUITs to form a unit. Data error in file at line 'l'

Check that the unit following line 'l' is either a RIVER, CONDUIT, REPLICATE or INTERPOLATE section and that the keyword is correctly spelt. Also check that the distance to next cross section is nonzero for the current unit, which is the first in a reach.

E1129

It is not possible to find a solution with the current time step - You should try to decrease the time step and run it again

A very large matrix coefficient has been found - this indicates instability. This is the earliest unit within the data file at which this error has been found - the source of the instability may be at this unit, or nearby.

E1131

Water level outside channel boundary between 'label1' and 'label2' - intrp failure in rkutta (intok = 'x')

The direct steady solver has calculated a water level outside the channel boundary: check the channel data at 'label1' and 'label2'; improve the flow split estimates in the initial conditions; or use the pseudo time stepping method. This indicates an instability at this unit or just downstream (upstream if flow is supercritical, using the Direct Method Transcritical Solver); try examining the data here or add extra interpolated sections.

E1133

X' extra sections gave insufficient accuracy between 'label1' and 'label2'. This may be due to the water level exceeding the max level of section data. Try extending your section data.

The direct steady method failed to solve the flow equations to sufficient accuracy.  Check and/or extend the channel data at 'label1' and 'label2'; improve the flow split estimates in initial conditions; use the pseudo time stepping method. This error may also occur if extra BERNOULLI LOSS units are required; e.g. between a RIVER and CONDUIT unit. This indicates an instability at this unit or just downstream (upstream if flow is supercritical, using the Direct Method Transcritical Solver); try examining the data here or add extra interpolated sections.

E1139

'Unit' - no. of stage/gate opening datasets > 4. 'unit' data error at line 'l'

Obsolescent tidal sluice units RNTRS/RNDSC only - the number of stage/gate opening data pairs must be between 2 and 10 inclusive.

E1159

Length of crest in direction of flow must be > 0.1 - rnweir data error at line 'l'

Increase the length of the round-nosed, broad-crested weir crest in the direction of flow to a minimum of 0.1m.

E1168

'x' unit(s) not yet available with the direct method - run terminated

The units listed above this message are not available for the direct steady state method. Either substitute alternative units or use the pseudo time stepping method. This should not apply to any currently supported units.

E1169

Pump is in stopped mode; This mode is incompatible with the direct method.

The direct method cannot handle zero flow through in-line structures.

E1179

Remote upstream control not yet available. For use with the direct method.

Use pseudo-timestepping for steady runs, or time or logical control (in MANUAL mode) to control.

E1184

'unit' - third label required for WATER3 option - 'unit' data error at line 'l'

For 'water' mode the label for remote water level control must be specified after the two normal unit labels; alternatively, use logical rules.

E1185

Values given must be greater than zero

Either the operating rate or maximum opening has been set to zero, or the maximum setting is set less than the minimum.

E1188

No gate opening given for MANUAL operation

MANUAL mode has been chosen, but no setting has been given. Set a value in the control table.

E1189

No initial gate opening given for AUTO operation

Gates starting in AUTO mode used to require an initial setting (obtained from the control table). NB This should no longer be possible

E1195

Matrix structurally singular. iflag = -1 no value for matrix column 'x' this column is associated with label 'l'

This error indicates an inconsistency in the model network or initial conditions. It may be caused by invalid model connectivity, inappropriate zero flow or zero coefficients otherwise obtained, e.g. by bad data not otherwise picked up. Details of labels involved can be obtained by responding 'y' to the 'network check' prompt.

E1196

Matrix numerically singular. iflag = -2

This message indicates mathematical indeterminacy, caused by the solution matrix being singular (non-invertible). This may be caused by an unexpected or temporary area of zero flow altering the structure of the matrix. This can often be resolved by setting the Matrix Dummy Coefficient (Parameters tab on the 1D Simulation interface) to a small number, e.g. 0.001 or lower. This will preserve the intended structure of the matrix and make it less likely to be singular, whilst having a negligible effect on the solution.

E1197

Row or column index out of range. iflag = -12

This error indicates an inconsistency in the model network connectivity. Details of labels involved can be obtained by responding 'y' to the 'network check' prompt.

E1198

Dir = 'x' reverse flow direction hn1 = 'y' hn2 = 'z' node = 'n'

The direct steady method has calculated a flow reversed on a spill and has not been able to continue computations.  A solution may be obtainable by improving the flow split estimates in the initial conditions or by using the pseudo time stepping steady method.

E1199

Error in spill at line 'l'. bank chainage must increase for each data pair

If a vertical spill section is required use a small increment to the chainage (eg 0.01m).

Message

Description

E1200

Maximum gate opening MUST be less than radius plus height of pivot

This opening is not physically possible - check the maximum gate settings and gate dimensions.

E1201

Gate opening MUST be less than radius plus height of pivot

This opening is not physically possible - check the maximum gate settings and gate dimensions.

E1202

Gate radius MUST be greater than height of pivot

A radial sluice unit must be dimensioned so that the gate can fully shut if required, this the radius must be greater than or equal to the height of pivot above weir crest. Check the dimensions of the gate, or consider an alternative method (e.g. an orifice unit in parallel or a nonzero minimum setting) if permanent undershooting is required.

E1203

Number of data points in SPILL unit must be must be greater than 1

Check the spill data and add more data points.

E1210

Negative flow specified at a Q:T boundary - this is not permitted in the current version of the direct method ('label')

Change the schematisation to allow a positive Q:T or use the pseudo time stepping steady method

E1211

Perturbation matrix is singular

The direct steady method has detected a mathematical singularity - this is often caused by zero flows. A solution may be obtainable by: removing the zero flow reach slightly opening closed sluice gates using the pseudo time stepping steady method

E1219

cv outside allowed range

The coefficient of velocity specified for a general purpose weir unit must be between unity and 1.5 inclusive.

E1221

rlimit outside allowed range

The modular limit specified for a general purpose weir unit must be between zero and unity inclusive.

E1230

Suter pump - numerical data outside allowable range

Allowable number of characteristics per stage is between 1 and 50 inclusive.

E1234

Generic error code used for problems that would cause Flood Modeller  to crash, usually due to a potential mathematical error.  For example, the code would appear if the breadth of a weir was set to a negative value

The solution is dependent on the particular error, which is detailed further in the error text. For further information on a particular error, please Contact Flood Modeller Support.

E1237

SAAR must be positive for event rainfall calculation

Consult the appropriate handbook or software (e.g. FEH) for an appropriate SAAR (Standard Average Annual Rainfall) value.

E1238

Event Rainfall flag is expected to be OBSER, FEHER, FSRER, or PMFER

The correct rainfall flag will be set by choosing the correct option in the User Interface. If editing in a text editor, consult the Data Fields section for the Hydrological Boundary for the correct format.

E1239

Positive non-zero value is expected for the OBSERVED event rainfall

An observed event rainfall has been entered, but no rainfall depth set. This must be entered, and should be equal to the sum of the rainfall profiles (if user-input profile chosen; Tip: enter the rainfall profile in the table and select OK - the warning message will advise of the sum of the rainfall values, which can then be entered in the rainfall depth box).

E1241

Catchment Wetness Index flag is expected to be OBSCW, FSRCW or PMFCW

The correct CWI flag will be set by choosing the correct option in the User Interface. If editing in a text editor, consult the Data Fields section for the Hydrological Boundary for the correct format.

E1243

Percentage Runoff Flag is expected to be BSPR, FEHPR, FSRPR or F16PR

The correct PR flag will be set by choosing the correct option in the User Interface. If editing in a text editor, consult the Data Fields section for the Hydrological Boundary for the correct format.

E1244

Error in OBSERVED percentage runoff, it must not be > 100.0

An FSR/FEH boundary has been used with Observed PR (percentage runoff), which was set greater than 100. Check the data input.

E1245

Error in OBSERVED percentage runoff, it must not be <0.0

An FSR/FEH boundary has been used with Observed PR (percentage runoff), which was not set, or was set negative. Check the data input.

E1246

Time to Peak Flag is expected to be OBSTP, FEHTP, F16TP, FSRTP or R124TP

The correct Tp flag will be set by choosing the correct option in the User Interface. If editing in a text editor, consult the Data Fields section for the Hydrological Boundary for the correct format.

E1247

Positive non-zero value is expected for the OBSERVED Time to Peak, TP

An FSR/FEH boundary has been used with Observed Tp (time-to-peak), which was not set, or was set negative. This is not allowed. Check the data input.

E1248

Positive non-zero value is expected for the Calibration factor of TP

An FSR/FEH boundary has been used with a zero or negative Tp (time-to-peak) calibration factor. Since this is a multiplicative factor, it must be positive. Check the data input.

E1249

Base Flow Flag is expected to be OBSBF or F16BF

The correct BF flag will be set by choosing the correct option in the User Interface. If editing in a text editor, consult the Data Fields section for the Hydrological Boundary for the correct format.

E1250

Positive non-zero value is expected for the catchment area, carea

Consult the appropriate handbook or software (e.g. FEH) for the appropriate catchment area.

E1253

Unit Hydrograph Flag is expected to be OBSUH, FSRUH, UBRUH or SCSUH

The correct UH flag will be set by choosing the correct option in the User Interface. If editing in a text editor, consult the Data Fields section for the Hydrological Boundary for the correct format.

E1255

Rainfall Profile Flag is expected to be OBSRP, WINPMP or SUMPMP

The correct rainfall profile flag will be set by choosing the correct option in the User Interface. If editing in a text editor, consult the Data Fields section for the Hydrological Boundary for the correct format.

E1256

Number of rainfall values outside range

Check that the number of rainfall values in an observed rainfall profile is greater than zero. The maximum is 4601 - check that this is not exceeded; if it is, consider increasing your time interval, splitting up your simulations or select an alternative hydrological method.

E1258

ERROR in calculated percentage runoff at subroutine prcal, it is > 100.0

Percentage runoff is calculated from a combination of SPR and dynamic PR. An unrealistically high value of CWI or total precipitation, or a high value of SPR may cause this to exceed 100. Check these values and refer to the documentation for further

E1262

Error in routine interp in fsrqt - value out of range

The FSR (and FEH) methods interpolate values for Storm Return Period (from Flood Return Period), CWI (from SAAR) and two year growth factor (from m5 rainfall). It is likely that one of these values is out of range.

E1266

Calculated no of unit hydro. Ordinates, x, is greater than max allowed of y

The number of hydrograph ordinates after convolution has exceeded the maximum, due to either too many unit hydrograph ordinates or rainfall profile values.

E1267

For SUMRP unequal return periods are unacceptable. This can, however, be forced by using the parameter FORCE.

For FSR/FEH boundaries, the summer flood and storm periods should be set equal. This can be relaxed by not selecting 'FORCE' equal return periods.

E1268

Invalid Velocity Flag at line 'l'

Velocity calculations in MUSKINGUM units should be calculated using the keyword VQ POWER LAW, VQ RATING or VQ SECTION.

E1269

Power law constants cannot be negative at line l

The constants in the Power Law relationship, a, b, V0 and Q0, may not be negative.

E1285

Reservoir/Pond level is lower than or the same as the previous level

The elevations in a reservoir or pond unit should be entered in ascending order. Otherwise, inconsistencies in interpolating areas/volumes may occur. Check input data.

Message

Description

E1301

No flow boundaries have been defined therefore direct steady method is not applicable

The direct method requires a QT-type boundary at each upstream branch end of the model

E1302

No head boundaries have been defined therefore direct steady method is not applicable

The direct method requires a HT/QH-type boundary at each downstream branch end of the model

E1324

Number of q:h data pairs exceeds the maximum permitted

A QHBDY or QH control unit may contain a maximum of 500 Q:H data pairs.

E1330

Efficiency values must be greater than zero and less than or equal to one: effopt = 'e'

User input value of optimal efficiency, 'e', for the PUMP unit must be positive and no greater than 1.

E1331

Optimal head and flow values must both be positive: qopt = 'q'; hopt = 'h'

User input values of optimal flow, 'q', and head, 'h', for the PUMP unit must be positive.

E1332

Number of switch data sets must be > 1

This applies to the PUMP unit - ensure that the number of time control values is at least two.

E1333

Invalid switch type keyword: 'a'

Control method for pumps must be TIME, LOGICAL or CONTROLLER

E1334

Unrecognised pump mode keyword: 'a'

Valid PUMP modes can be only ON, OFF, STOPPED or OPEN

E1336

Missing control label for controller switch type

When using controller mode (PUMP unit), the controller label field must be used

E1338

Time multiples must be positive: itmult = 'i';timstr ='t'

Invalid time unit keyword, 't', entered, or user defined time multiplier 'i' is zero/negative (PUMP, SLUICE or GATED WEIR units)

E1339

Unrecognised pump mode: imnew='m'

A bad pump mode 'm' has been set. Valid modes are 0-2 and 10-14. This should not be possible, but could occur if the initial condition mode is invalid.

E1340

Number of Suter points must be between 1 and 133. nsut = 'n'

The number of calculated points, 'n', on the pump curve exceeds the maximum. This may be caused by too many user-input points. A maximum of 89 extra points are extrapolated using Suter's method, leaving at least 44 user-input data sets available.

E1341

No corresponding pump mode given for MANUAL operation at model time "m" hours.

No operating mode was given in the PUMP control table when in MANUAL mode.

E1343

Number of head, flow, efficiency data sets must be between 1 and 50.

The number of user-input flow-head-efficiency data sets exceeds the maximum (now 133). Note that the effective maximum is considerably less, otherwise error E1340 is likely to be flagged.

E1344

Error reading data in datafile.

Data read error in flow-head-efficiency table for PUMP unit. Most likely caused by non-numeric characters present in the field

E1345

Head, flow and efficiency cannot all be simultaneously greater than zero.

Head and flow values have been input as greater than zero; efficiency is greater than 1. This is not permitted.

E1346

Invalid number of switch data sets: 'n'

Number of time control data sets, 'n', in the pump unit is less than one - at least one must be added to the control table.

E1347

Unknown switch type: type code = 'a'

Control method for pumps must be TIME, LOGICAL or CONTROLLER

E1348

Unable to find control unit for controller mode: 'c'

No control unit existed associated with the controller label 'c'. (PUMP unit)

E1349

Unknown instruction code for logical switching: 'a'

Instruction to operate a pump in logical rules must be 'PUMP'. Instruction 'a' supplied.

Message

Description

E1401

Skew angle of bridge > 45 ; Must be in range 0 < =angle < =45.

Skew angle for USBPR bridge must be less than 45 degrees. Check input data.

E1402

Width of bridge< =0.0. Data error in bridge attached to 'label1', 'label2'

Distance between faces of dualled bridge (Arch or USBPR) is input as zero - this is not allowed. Check "Bridge Width" input data.

E1403

Invalid bridge abutment code. Should be 1, 2 or 3. Data error in bridge attached to 'label1', 'label2'

Check USBPR bridge 'Abutment Type' input data.

E1404

Pier coefficient out of range. Must be >=0.0 and < =8.0. Data error in bridge attached to 'label1', 'label2'

Invalid pier calibration number (USBPR bridge - Pier Data). Must be between 0 and 8.

E1405

Invalid bridge pier description. 'x'(Number of piers), 'y' (type of shape of bridge soffit), 'z' (type of bridge pier cross sectional type).Data error in bridge attached to 'label1', 'label2'.

Invalid shape description (USBPR bridge - Pier Data). See USBPR section in Help for valid combinations.

E1406

Number of bridge piers >0 , with Width of bridge piers < =0.

Pier width must be positive if piers are specified (USBPR bridge - Pier data)

E1410

Too many culverts in bridge attached to 'label1','label2'.

Maximum number of flood relief culverts in a USBPR bridge is 20.

E1411

Culvert drowning coefficient must be <1. Data error in bridge attached to 'label1','label2'

Check USBPR bridge Flood Relief Culvert data

E1412

Culvert invert level is greater than soffit level. Data error in bridge attached to 'label1','label2'.

Check USBPR bridge Flood Relief Culvert data

E1421

Number of arches < 0 in line 'l'

The number of arches in a bridge unit has been set negative - check the data file at line 'l'.

E1422

Number of arches exceeds the maximum of 'x' (maximum number of arches).

The current maximum number of arches in a bridge unit is 25.

E1423

USBPR Bridge error on arch 'x' (number of arch) x coord of left side of arch must coincide with cross chainage point

The cross chainage value for the bridge opening must also be present in the bridge section data (i.e. the arch must be sprung from a point directly in vertical line with a cross-section data point).

E1431

Too many markers in bridge channel section at line 'l'.

Left and right embankment markers have been specified more than once for the same bridge section - this is not allowed.

E1432

Left or Right markers wrong in bridge section.

Left and right embankment markers are the wrong way round, or only one of them has been set.

Message

Description

E1510

Unrecognised direction keyword keyword should be UPSTREAM or DOWNSTREAM

Only UPSTREAM and DOWNSTREAM are allowed keywords for the CULVERT BEND/ GENERAL HEAD LOSS unit.

E1511

Invalid loss coefficient:Loss coefficient must be value between 0 and 10.

The loss coefficient for the CULVERT BEND/ GENERAL HEAD LOSS unit must be in the range 0-10; advisory warnings appear if the value is above 1 (general) or 0.5 (bend)

E1512

Upstream section for a BEND/LOSS unit in upstream control must be a RIVER or CONDUIT unit.

The CULVERT BEND/ GENERAL HEAD LOSS unit needs to be able to calculate flow areas at the unit in the control direction, so this unit must be a channel section. Use remote nodes if this is not connected directly to such a unit.

E1513

Invalid loss coefficient: Loss coefficient should be value between 0 and 1.

Invalid value given for the loss coefficient for a CULVERT OUTLET unit

E1514

Unit upstream of a CULVERT OUTLET unit must be RIVER or CONDUIT unit.

The CULVERT OUTLET unit must be at the downstream end of a properly formed reach of CONDUIT units. This is so that flow areas and velocities within the culvert barrel can be calculated. Use remote nodes if this is not connected directly to such a unit.

E1515

Unrecognised conduit type code. Should be A or B

This code determines the equations used in submerged inlet control. Only Type A or Type B is valid. Please refer to the Culvert Inlet topic for more information.

E1516

Value of unsubmerged inlet control loss coefficient should be between 0 and 1; current value is x

Invalid value given for the unsubmerged inlet control loss coefficient for a CULVERT INLET unit.

E1517

Value of exponent for inlet control should be between 0 and 3; current value is:x

Invalid value given for the unsubmerged inlet control for a CULVERT INLET unit.

E1518

Value of submerged inlet control loss coefficient should be between 0 and 0.1; current value is x.

Invalid value given for the submerged inlet control loss coefficient for a CULVERT INLET unit.

E1519

Value of submerged inlet control adjustment factor should be between 0 and 1; current value is x

Invalid value given for the submerged inlet control adjustment factor for a CULVERT INLET unit

E1520

Value of outlet control loss coefficient should be between 0 and 1; current value is x

Invalid value given for the outlet control loss coefficient for a CULVERT INLET unit

E1521

Value of trash screen width should be greater than 0; current value is x

Invalid value given for the trash screen width for a CULVERT INLET unit.

E1522

Value of trash screen bar proportion should be between 0 and 1; current value is x.

Invalid value given for the trash screen bar proportion for a CULVERT INLET unit.  This number represents the proportion of the total trash screen area that is occupied by the bars.

E1523

Value of trash screen blockage ratio should be between 0 and 1; current value is x.

Invalid value given for the trash screen blockage ratio for a CULVERT INLET unit.  This number represents the proportion of the trash screens total area that is blocked by debris.

E1524

Value of trash screen head loss coefficient should be greater than 0; current value is x

Invalid value given for the trash screen head loss coefficient for a CULVERT INLET unit.

E1525

Unit downstream of a CULVERT INLET unit must be a RIVER or CONDUIT unit.

The CULVERT INLET unit must be at the upstream end of a properly formed reach of CONDUIT units.  This is so that flow areas and velocities within the culvert barrel can be calculated. Use remote nodes if this is not connected directly to such a unit.

E1526

Maximum number of transcritical points exceeded between l1 and l2

The maximum number of transcritical points (super-subcritical and sub-supercritical transitions) for the Direct Method Transcritical Solver is 50. The 51st such point occurred between nodes l1 and l2.

E1528

Junction at l1 appears to be neither a join nor a split

This should not be possible. If it occurs, check the connectivity of the junction at node l1.

E1529

Unable to find unit number n in list of river reaches transcritical point found in non-river between l1 and l2

This should not be possible. If it occurs, check the nth unit of the model (labels l1 and l2) - this should be a channel unit.

E1530

Internal error - invalid transcritical point type n between l1 and l2

This should not be possible. If it occurs, please Contact Flood Modeller Support.

E1532

Upstream/downstream nodes of unit l1 are not rivers/conduits. Direct supercritical method cannot handle this try adding a dummy reach at either end

Supercritical flow has occurred in the Direct Method Transcritical Solver at two consecutive non-channel units at node l1 - a dummy reach needs to be inserted between them for the method to work.

E1533

Cannot find label l1

The adjoining unit at the end of a reach cannot be found. Check the connectivity at label l1.

E1534

Save interval (or timestep) must be positive

A zero or negative save interval (interval at which results are saved) or timestep has been entered - check the 1D Simulation interface or the ief file.

E1536

Upstream/donwstream/remote/constriction section label l1 does not exist.

The remote node label (or reference node label for a blockage unit) does not exist - check that it exists in the network. Pay attention to case (1D node labels are case sensitive).

E1537

Upstream and/or downstream river units at bridge not found; upstream label used = l1; downstream label used = l2; use remote nodes if river units are not adjacent to the bridge

Check the connectivity of the bridge unit in question - a bridge must be connected directly (1st/2nd labels) or remotely (3rd/4th labels) to channel units, from which to obtain areas, and hence velocities. If the nodes up/downstream are not channel units, use remote nodes.

E1538

Culvert flow failed to converge

Could not find a solution for the flood relief culvert flow within a bridge.

E1539

Perturbation failed.

Direct method could not find a solution at the qh control or pond unit. Try adjusting the flow splits in the initial conditions.

E1540

No nodes found

No nodes present in the model - this message can appear only if the 'write Unit Data Store' option is chosen, and should not in fact be possible.

E1541

Country must be ENGLAND, IRELAND, SCOTLAND or WALES

The FSSR16 unit must specify either ENGLAND, IRELAND, SCOTLAND or WALES as the country - the method applies only to UK/Ireland. For other countries, the US SCS method may be considered.

E1542

Value of s1085 must be positive for time to peak calculation

S1085 (stream slope measurement) must be positive - used in time to peak calculation for FSSR16 unit.

E1543

Value of MSL must be positive for time to peak calculation

MSL (main stream length measurement) must be positive - used in time to peak calculation for FSSR16 unit.

E1543

Value of DPSBAR/DPLBAR must be positive for time to peak calculation, or PROPWET must be between 0 and 1.

Invalid catchment descriptor as used in an FEH unit - either DPLBAR, DPSBAR are zero or negative, or PROPWET is outside the range 0-1 (see individual error text for details)

E1544

SOIL must be between 0 and 1.0

Obsolescent FSR unit only - invalid SOIL value entered.

E1545

Time step must be positive

Time interval for hydrological boundary is entered as zero or negative. Check the unit form or data file.

E1546

Urban fraction/extent cannot be <0 or> 1

Invalid value entered for Urban Fraction (FSSR16) or URBEXT (FEH/ReFH) - must be between 0 and 1.

E1547

Storm duration of x is less than or equal to zero.

A zero or negative storm duration has been entered for a hydrological boundary.

E1548

[Time] interpolation error

Error in the multipurpose interpolation routine used for hydrological boundaries caused by the reference table (for the independent variable) having two equal values.

E1549

INTERPOLATE unit must have a positive chainage

An INTERPOLATE unit has been entered with zero or negative chainage (distance to next cross section) - this is not permitted - an INTERPOLATE unit cannot terminate a reach.

E1550

A reach has more than 100 interpolated sections (split the reach using a RIVER)

There can not be more than 100 consecutvie INTERPOLATE units. If more are needed, then replace one with a RIVER unit with appropriate section.

E1551

Numb=0 in INTERPOLATE

This should not be possible - this should equal the number of consecutive INTERPOLATE units. If this error occurs, please contact Flood Modeller Support.

E1552

Total chainage must be positive

The total [cumulative] chainage of consecutive INTERPOLATE units is zero or negative - this is not allowed.

E1555

Unit type may not be connected to junction at label l1

A junction may not be connected directly to another junction or a reservoir. Combine the nodes into a larger junction or insert a dummy reach/unit between the two.

E1562

dx must be positive

A dx value has been assigned, and discovered in the 2d or sediment module. This should have been trapped previously.

E1564

... number of data points is less than 2

Less than two points have been entered in the wavespeed/attenuation data table (VPMC only) or the VQ rating table in any Muskingum unit.

E1565

... number of data points greater than n

The maximum number of points (currently 452) has been exceeded in the wavespeed/attenuation data table (VPMC only) or the VQ rating table in any Muskingum unit.

E1566

Lateral inflows cannot be used with MUSKINGUM units.

Lateral inflows are not allowed with MUSKINGUM fixed (i.e. not VPMC, XSEC or RSEC) units. NB This error code also appears if a lateral inflow is connected to the last section of a reach.

E1567

Zero wavespeed or chainage Ensure that the reach is not dry.

This error occurs in calculating Muskingum VPMC routing parameters. It may be alleviated by selecting a nonzero smoothing factor, so that the wavespeed is always positive.

E1568

Slope must be positive.

This may occur in a MUSX-XSEC unit (channel slope), or a Flat-V weir unit (V-slope), netierh of which is allowed to have a zero slope.

E1569

Channel section data error. At least 2 section points and a positive slope are required for velocity calculation at line n

This occurs in a MUSK-XSEC unit with a VQ SECTION velocity calculation if there are less than two section points or a zero/negative slope (a positive slope is required for normal depth).

E1570

Attempt to read results from before start of run. Start your run with structure in MANUAL mode.

When using rules based on previous results (OLD*), the historic time referred to by the OLD* function preceded the model start time, and the condition is therefore not available. One must use the affected units in MANUAL mode (or use alternative rules for this period) for a time greater than or equal to the greatest time amount looked back, i.e. if OLD* references a condition 900s ago, the rules must not take effect until 15 minutes into the simulation.

E1571

Error attempting to read earlier result.

Generic read error from zzn file in accessing results for rules based on previous results (OLD*). The zzn file may be corrupt.

E1572

Unrecognised operation type

Invalid operator for rules based on previous results (OLD*). Valid operators are OLDH (head), OLDF (flow), OLDM (mode) and OLDS (unit state). Check the rules syntax.

E1573

Weir discharge coefficient must be greater than 0

Weir discharge coefficient was set zero or negative in a PUMP (in open mode), ORIFICE or SYPHON unit.

E1574

Surcharged discharge coefficient must be greater than 0

Surcharged discharge coefficient was set zero or negative in a PUMP (in open mode), ORIFICE or SYPHON unit.

E1575

Pump bore area must be greater than 0

Bore area was set zero or negative in a PUMP (in open mode), ORIFICE or SYPHON unit.

E1576

Soffit must be higher than invert

The soffit level was set higher than or equal to the invert level in a PUMP (in open mode), ORIFICE or SYPHON unit - this is not allowed.

E1577

Bridge soffit is more than 10m above cross section. Please extend your section data or modify the arch dimensions.

The soffit of the bridge is not allowed to exceed the bridge section data by more than the input parameter dfloodb (default 10m). This is to allow section properties to be interpolated at a reasonable resolution. One can add extra depth to the section data by adding extra points at the left and right extremeties and extending them vertically.

E1578

icount is zero - arch error

This should not be possible - this should be the number of section data points contained underneath an arch. Check that the arch is sprung from a point directly above existing section data.

E1579

Conduit section should start with x=0 at invert centre line

The first and last point of a (symmetrical) CONDUIT SECTION must both be at x=0. If required, one can use the Modify tool in the unit form to add/subtract a constant value from a table of (x-)values.

E1580

Unrecognised time factor keyword

An invalid time factor keyword or a zero/negative time multiplier was entered for the time units. Common valid keywords are 'SECONDS', 'MINUTES', 'HOURS', 'DAYS'. See the data fields section for the relevant unit for a full list.

E1581

Flood Modeller has detected a different label length in the initial conditions file from the value in operation in the datafile. This is not allowed.

This can occur if using a model data file (default label length 12) with initial conditions from an old model (label length 8), or vice versa. It is recommended to convert all models to label length 12. To convert a model data file from length 8 to length 12, start with a blank file in the User Interface, use the Load 1D Network in the Home tab and save. The new imported model will automatically become a 12-character length label model. To convert an initial conditions file from length 8 to length 12, ensure that the header reads 'label12', as opposed to 'label', and insert four blank spaces between each node label and the 'y' tag; note that the 'y' tag should now be in the 14th column.

E1582

Maximum number of pond data lines exceeded (max=50) at label l1

A maximum of 50 elevation/area data pairs are currently allowed in the POND unit.

E1583

INTERPOLATE must be preceded by a RIVER or REPLICATE with a positive chainage

The preceding channel unit has a chainage (distance to next cross section) value of zero. This is not allowed (nothing to interpolate). Check the connectivity of your model, and that a positive chainage was entered in the preceding section unit.

E1584

Non-channel unit found in the middle of a reach. Reach must end with dx = 0.

The last section unit in the reach had a nonzero distance to next cross section value. The last section of a reach (i.e. before a structure, boundary or junction is encountered) must have a distance to next cross section value of zero.

E1585

Length of weir in direction of flow is more than 100 x width of crest. This is not acceptable

The length of the weir has exceeded the breadth by a factor of 100 or greater. This invalidates the limits of applicability, and is also unlikely. Check that the correct dimensions for each has been entered.

E1586

Crest length must be positive

A zero or negative length has been entered for the weir - check inputs.

E1587

Unknown controller operation mode

Control sub-mode within LOGICAL or CONTROLLER mode must be either 'AUTO' or 'MANUAL'. Check inputs.

E1588

Unknown sluice gate operation mode

Invalid control mode detected - must be 'TIME', 'LOGICAL', 'CONTROLLER', 'WATER1', 'WATER2' or 'WATER3'.

E1589

No time data available in switch data set for current model time

The model time is not covered by the times in the control table. Ensure that the times within encompass all the simulation run time. Use the EXTEND flag if necessary.

E1590

Unable to find controller label for controller mode

Controller label referenced by unit in CONTROLLER mode is not found in the control file.

E1591

Unknown controller operation mode

Invalid control mode found - should be CONTROLLER or LOGICAL (MANUAL or AUTO).

E1592

Error in floodplain section at line n. Chainage must be positive for friction flow

Friction flow has been specified for a FLOODPLAIN SECTION unit, but the chainage was entered as zero. A positive chainage is required for the slope, in order to calculate friction flow.

E1593

First matrix element is zero

This occurs in the spline interpolation module, and is most likely caused by a non-increasing independent variable. Check that all these values are in strictly ascending order.

E1594

Xset points are not all distinct. Xset range = x1, x2; X point = x3; ... nset = n.

This occurs in the spline interpolation module by having non-distinct values of the independent variable close to the current point in question (x3). The range of the independent variable is x1-x2, and there are n points in the table. This information may assist in identifying the table being interpolated.

E1595

Gate orientation must be FORWARD or REVERSE

Invalid keyword entered for the GATED WEIR unit orientation - this must be 'FORWARD' or 'REVERSE'. Check inputs.

E1596

ctc must be greater than 0

Discharge coefficient for throat control in a GATED WEIR unit has been entered as zero/negative. Check inputs.

E1597

cgt must be greater than 0

Discharge coefficient for gate control in a GATED WEIR unit has been entered as zero/negative. Check inputs.

E1598

crev must be greater than 0

Discharge coefficient for reverse flow in a GATED WEIR unit has been entered as zero/negative. Check inputs.

E1599

dr must be greater than 0

Modular limit in a GATED WEIR unit has been entered as zero/negative. Check inputs.

Message

Description

E1600

Only one gate is allowed in gated weir

Currently in a GATED WEIR unit, only one gate is allowed per unit. To connect more gates in parallel, copy the unit and connect multiple units at their upstream and downstream ends via junctions.

E1601

Gate height must be greater than zero

Gate height in a GATED WEIR unit has been entered as zero/negative. Check inputs.

E1602

Gate crest higher than max. gate height

Input or calculated gate crest level has exceeded the maximum level of the gate for a GATED WEIR unit. Check user input opening values, and also maximum gate opening.

E1603

Crest is lower than sill

Input or calculated gate crest level is below the sill for a GATED WEIR unit. Check user input opening values, and also minimum gate opening.

E1605

Unit version number n is not supported in this version of Flood Modeller

The version number for the Unit in the data file is newer than the version of Flood Modeller being run. You'll need to upgrade to a newer version of Flood Modeller. Contact Flood Modeller Support for details.

E1606

Negative breach width xm is invalid

User has entered a negative width of x in the BREACH units. Check inputs.

E1607

Negative breach side slope x is invalid.

User has entered a negative slope of x in the BREACH units. Check inputs.

E1608

Error in breach: unable to fit breach, check the breach and associated spill section

An extension of the breach geometry (either at the left or right end) does not reach the spill geometry, thus a breach cannot be formed from the original spill unit. Check the dimensions of the breach and spill unit.

E1610

Invalid blockage proportion x. Proportion p must have 0.0 < = P <=1.0

An invalid blockage proportion has been entered. Note that the valid range is 0 to 1. Check inputs.

E1611

Upstream/Downstream/Constriction unit of a blockage (connected or remote) must be RIVER, CONDUIT or BRIDGE unit.

In order to calculate velocities, units connected to a blockage unit must have an area, i.e. be section units. If this is not the case for the units connected directly, appropriate units may be connected remotely (3rd, 4th and 5th labels) from which to obtain areas.

E1612

Invalid loss coefficient: Loss coefficient must be at least 0.

A negative value for the loss coefficient has been entered for the blockage unit. Check inputs.

E1613

OPEN pump operation is specified but parameters for OPEN operation are not set

Pump mode has been specified as being in OPEN mode, but the input or calculated mode is not 'OPEN' (or a valid open mode numeric 10-14).

E1614

Selected node l1 for OLD rules has been removed from the output list

The node label l1 is not in the results list. Check that the node exists in the model and that its tag is set to 'y' in the initial conditions.

E1620

Unit not supported in this version of Flood Modeller

The version number for the Unit in the data file is newer than the version of Flood Modeller being run. You'll need to upgrade to a newer version of Modeller. Contact Flood Modeller Support for details.

E1621

Invalid lateral inflow weight factor (= x) entered for connecting unit

Error in lateral inflow unit - the area or reach weight factors must be positive and sum up to one, therefore a negative value or a value exceeding one is not permitted.

E1622

User defined weight factors do not sum to 1.0

Error in lateral inflow unit - the area or reach weight factors must be positive and sum up to one (or less than one if only partially using weight factors).

E1623

Unrecognised connecting boundary node entered: l1

The node attached as the inflow to the lateral inflow unit must be an inflow or rainfall-type boundary.

E1624

Link to lateral inflow not recognised

Check connectivity of the lateral inflow unit and lateral nodes.

E1625

Reservoir connected to reach - weighted lateral inflow at l1

A lateral inflow into a reservoir unit may not be weighted by reach length - change the weighting method in the lateral inflow unit to area or user defined, or override for this node only using a user defined (custom) weighting.

E1627

Connected Muskingum to l1 has zero reach length

A lateral inflow has been connected to a Muskingum unit of zero length, i.e. the last section in a reach. This is not allowed, since the inflow is applied to the length immediately downstream of the section. One needs to attach the lateral inflow to the section at the upstream end, or remove it.

E1628

Weight factor type not recognised: l1

The weight factor keyword must be one of 'REACH', 'AREA' or 'USER', to denote whether the weighting of the lateral inflow is determined by relative length of reach, surface area (e.g. for rainfall) or user-specified, respectively. Check inputs.

E1629

Muskingum section connected to area distributed lateral - l1

A lateral inflow connected to a Muskingum unit cannot be weighted by area - this is because the width, and hence surface area of a Muskingum unit is not generally known.

E1630

This Muskingum type will not receive lateral inflows

Lateral inflows are not allowed with MUSKINGUM fixed (i.e. not VPMC, XSEC or RSEC) units.

E1631

Zero reach length river section connected to lateral inflow

A lateral inflow has been connected to a channel unit of zero length, i.e. the last section in a reach. This is not allowed, since the inflow is applied to the length immediately downstream of the section. One needs to attach the lateral inflow to the section at the upstream end, or remove it.

E1640

Number of data pairs must be greater than zero

No rainfall/time data pairs have been entered in the table for a Rainfall-Evaporation boundary (REBDY) unit.

E1641

No input data types recognised

Rainfall-type boundary does not have any of the following specified: Rainfall, Evaporation, Evapotranspiration or Infiltration. Data for at least one of these must be present.

E1642

No data in l1 at line n before/after x hrs

The rainfall input data does not exist at the specified simulation time. Ensure that the rainfall data encompasses the start and end time of the simulation, using the EXTEND/REPEAT functionality if desired.

E1643

2 data points with same time

Two rainfall data points have been input with the same time. This is not allowed. Check input data.

E1644

Time values are not increasing.

The data in an REBDY are not in ascending time order. Check input data.

E1669

Zero or Negative slope encountered in Normal depth boundary This is not permitted.

A positive slope is required in order to calculate normal depth. This can be overcome by entering a user-defined slope value, or using a remote slope node (4th label) so that the mean slope is positive (i.e. downhill).

E1672

Remote label not found or not connected to a channel section.

The remote node label (3rd label) in an NCDBDY unit, if specified, must be of a channel type, from which to calculate conveyance.

E1673

No valid path found from upstream to downstream slope extents.

The upstream slope extent (4th label) in an NCDBDY must be connected by a single direct route to the downstream section. If there are alternative routes (e.g. the network is branched in between) or the route is complex, the user may be advised to enter a user-specified slope value.

E1674

No section data specified or available for normal/critical depth boundary.

Section data has been specified for the geometry of an NCDBDY but is empty, or the node is not a channel unit. Make sure the data is entered if specified, or that the node (or remote node) is coincident with a channel unit

E1675

Zero area or width in Critical depth boundary

A zero area or width has been detected in the NCDBDY critical depth boundary. Critical depth is not possible. This may be because the channel has run dry, or a conduit is running full.

E1676

No sign change detected in normal depth equation. Normal depth could not be calculated

No solution could be found for the normal depth equation. Normal depth may be higher than the top of the section data. Check the section data and extend if necessary; this may also be a sign of model instability.

E1678

Data error at line n. Dry lower depth greater or equal to dry higher depth

The lower depth limit used to relax the convective acceleration term in the momentum equation has been entered as higher than the upper limit. Check the input run parameters (low flow options).

E1680

Maximum number 50 of lateral connections for quality run exceeded

A maximum of 50 lateral inflow connections are permitted for a hydraulic simulation for 1D Quality. This is due to the maximum capacity in the 1D Quality connectivity.

E1681

Data error at line n. no RAD FILE tag found

The 'RAD FILE' line is not present in the GENERAL section at the top of the data file. This is required for CES simulations. Ensure the data file is saved as being v2.2. compatible, or later.

E1682

Data error at line n. no GENERAL tag found

The 'GENERAL' line is not present in the GENERAL section at the top of the data file. This is required for CES simulations. Ensure the data file is saved as being v2.2. compatible, or later.

E1683

Failed CES dll function call to SetRoughnessFile

Failed to load the SetRoughnessFile function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1684

Failed CES dll function call to GetRoughnessLoadingErrors

Failed to load the GetRoughnessLoadingErrors function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1685

Failed CES dll function call to AddSection

Failed to load the AddSection function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1686

Failed CES dll function call to PopulateSection for section id: l1

Failed to load the PopulateSection function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1687

Failed CES dll function call to AddSectionRoughness for section id: l1

Failed to load the AddSectionRoughness function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1688

CES dlls have not been initialised

Failed to load the CES dlls convey.dll and/or conveycalcs.dll. Check that the Flood Modeller and CES versions are compatible, and that the files convey.dll and conveycalcs.dll are present in the FloodModeller/bin folder or on the system path.

E1689

Failed CES dll function call to CalculateConveyance for section id: l1

Failed to load the CalculateConveyance function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1690

Failed CES dll function call to GetDepthIntervals

Failed to load the GetDepthIntervals function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1691

Failed CES dll function call to GetEddyViscosity

Failed to load the GetEddyViscosity function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1692

Failed CES dll function call to GetMinDepth

Failed to load the GetMinDepth function in convey.dll. Check that the Flood Modeller and Flood Modeller versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1693

Failed CES dll function call to GetNoPanels

Failed to load the GetNoPanels function in convey.dll. Check that the Flood Modeller and Flood Modeller versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1694

Failed CES dll function call to GetRelaxation

Failed to load the GetRelaxation function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder  folder or on the system path.

E1695

Failed CES dll function call to GetTemperature

Failed to load the GetTemperature function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the  FloodModeller/bin folder or on the system path.

E1696

Failed CES dll function call to GetMaxIterations

Failed to load the GetMaxIterations function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1697

Failed CES dll function call to SetRelaxation

Failed to load the SetRelaxation function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder  or on the system path.

E1698

Failed CES dll function call to SetDepthIntervals

Failed to load the SetDepthIntervals function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1699

Failed CES dll function call to SetEddyViscosity

Failed to load the SetEddyViscosity function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

Message

Description

E1700

Failed CES dll function call to SetMinDepth

Failed to load the SetMinDepth function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder folder or on the system path.

E1701

Failed CES dll function call to SetNoPanels

Failed to load the SetNoPanels function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1702

Failed CES dll function call to SetMaxIterations

Failed to load the SetMaxIterations function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1703

Failed CES dll function call to SetTemperature

Failed to load the SetTemperature function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1704

Failed CES dll function call to GetHytMultiplier

Failed to load the GetHytMultiplier function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder  folder or on the system path.

E1705

Failed CES dll function call to SetHytMultiplier

Failed to load the SetHytMultiplier function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1706

Failed function call to fn_requestoutputs_at_timestage for section: l1

Failed to load the RequestOutputsAtTimeTStageD function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1707

Failed function call to fn_get_isis_tables for section: l1

Failed to load the GetIsisTables2 function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1708

Failed CES dll function call to FnGetMinMax_Output_Elevations for section id: 'l1

Failed to load the GetMinMaxOutputElevations function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the  FloodModeller/bin folder or on the system path.

E1709

Failed CES dll function call to fngetmaxarea for section: l1

Failed to load the GetMaxArea function in convey.dll. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the  FloodModeller/bin folder or on the system path.

E1720

Too many substrings in rule l1

The depth of rule l1 is too large - try simplifying the rule, splitting into more than one if appropriate.

E1721

Parse error in rule l1

Error in parsing the rule data in l1. Check the syntax - check that the node label is spelt correctly (case-sensitive), the operators used are valid and for correct bracketing

E1722

Logical storage capacity exceded in rule l1

Rule l1 is too large - try simplifying the rule, splitting into more than one if appropriate.

E1723

Error in rule l1

A non-numeric value was read from Rule l1 when a numeric value was expected. Check the rule syntax.

E1724

Failed CES dll function call to SetConvTolerance

An error occurred whilst calling the CES dll in setting the convergence tolerance. Check that the CES_CONVERGENCE_TOLERANCE value in the ief file is entered correctly and is valid. Check also that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1725

Failed CES dll function call to GetConvTolerance

An error occurred whilst calling the CES dll in obtaining the convergence tolerance. Check that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1726

Failed CES dll function call to SetConveyanceType

An error occurred whilst calling the CES dll in setting the conveyance type. The value for CES_ROUGHNESS in the ief file should be 'LOWER', 'UPPER', or 'RECOMMENDED'. Check also that the Flood Modeller and CES versions are compatible, and that convey.dll is present in the FloodModeller/bin folder or on the system path.

E1727

Rule l1 has already been defined. Note that only the first 10 characters of the name are significant.

A duplicate rule name has been detected in the same unit. Note that only the first 10 characters of the rule name (e.g. 'Rule 1' are read).

E1728

Rule ALL is not valid. It could be confused with the keyword ALL in the TIME RULE DATA SET.

Naming a rule beginning with the characters 'ALL...' is not permitted. The keyword 'ALL' is reserved for the time-rule-data set table to denote all rules to apply. Rename the rule.

E1729

Fatal error in 2D solver

The program has terminated due to a fatal error in the 2d solver (e.g. TUFLOW); check the diagnostics for the 2d solver for more information.

E1730

Indeterminate flow direction in qxbdy

This should not be possible - the orientation of QXBDY could not be determined. Check the model connectivity.

Message

Description

E1800

Unknown bank type for section id: label1

An invalid bank type has been entered in CES Section node 'label1'. Valid types are 'RO', 'RI', 'RS', 'LO', 'LI', 'LS' or blank. Check data for node 'label1'

E1801

Sinuosity can only provided on a left bank in section id: 'label1'

A sinousity value in the CES section data table is only valid if coincident with a left bank marker. Check data for node 'label1'

E1802

Even number of bank markers required for section id: 'label1'

Each left bank marker in a CES section data table must have a corresponding right bank marker. Check data for node 'label1'

E1803

Put roughness chainage in ascending order for section id: 'label1'

The roughness table in a CES section unit must be entered in ascending cross-chainage order. Check data for node 'label1'

E1804

Put section chainage in ascending order for section id: 'label1'

The cross section data table in a CES section unit must be entered in ascending cross-chainage order. Check data for node 'label1'

E1805

RO bank marker must follow LI for section id: 'label1'

A left bank marker in a CES section data table must have a corresponding (and opposite - outer must match with inner) right bank marker. No other bank marker may be in between the two. Check data for node 'label1'

E1806

RI bank marker must follow LO for section id: 'label1'

A left bank marker in a CES section data table must have a corresponding (and opposite - outer must match with inner) right bank marker. No other bank marker may be in between the two. Check data for node 'label1'

E1807

LI bank marker must follow RO for section id: 'label1'

A left bank marker in a CES section data table must have a corresponding (and opposite - outer must match with inner) right bank marker. No other bank marker may be in between the two. Check data for node 'label1'

E1808

LO bank marker must follow RI for section id:'label1'

A left bank marker in a CES section data table must have a corresponding (and opposite - outer must match with inner) right bank marker. No other bank marker may be in between the two. Check data for node 'label1'

E1809

RS bank marker must follow LS for section id: 'label1'

A left straight bank marker in a CES section data table must have a corresponding right straight bank marker. No other bank marker may be in between the two. Check data for node 'label1'

E1809

RS bank marker must follow LS for section id: 'label1'

A left straight bank marker in a CES section data table must have a corresponding right straight bank marker. No other bank marker may be in between the two. Check data for node 'label1'

E1810

LS bank marker must follow RS for section id: 'label1'

A left straight bank marker in a CES section data table must have a corresponding right straight bank marker. No other bank marker may be in between the two. Check data for node 'label1'

E1811

Date out of range in section: 'label1'

The date of the simulation is invalid for the CES component - check the run times in the ief file are set and are covered by the time series data in the roughness (*.rad) file for all roughness zones in the CES Section node 'label1'.

E1813

No section data to calculate conveyance for section id: 'label1'

Error returned in call to CES to calculate conveyance. Check the cross-section data has been fully entered for CES Section node 'label1'.

E1814

No roughness data to calculate conveyance for section id: 'label1'

Error returned in call to CES to calculate conveyance. Check the roughness data has been fully entered for CES Section node 'label1'.

E1815

Roughness zone not found in roughness file for section id: 'label1'

Error returned in call to CES to calculate conveyance. Check the roughness zones entered in the roughness data for CES Section node 'label1' are all contained in the corresponding roughness (*.rad) file. Check the General section for the rad file being used.

E1818

[No message]

This error should never appear. No roughness file has been found, and CES sections are being used. This error should be trapped and explained elsewhere.

E1819

Data error at line X. failed to load roughness file.

The roughness file (*.rad) specified in the General section could not be loaded, and CES sections are present in the model. Check that the *.rad exists on the specified path, and is valid.

E1820

Non unique section name found for section id/replicate: 'label1'

The CES (or replicated CES) Section name 'labell1' has already been processed from the data file. Two channel sections of the same name in the same data file are not allowed. Check data and remove/rename one of the node labels.

E1821

Start date is out of the range specified in the roughness file for section id: 'label1'

The start date/time of the simulation is invalid for the CES component - check that real dates/times in the ief file are set and the start time is covered by the time series data in the roughness (*.rad) file for all roughness zones in the CES Section node 'label1'.

E1822

Finish date is out of the range specified in the roughness file for section id: 'label1'

The finish date/time of the simulation is invalid for the CES component - check that real dates/times in the ief file are set and the finish time is covered by the time series data in the roughness (*.rad) file for all roughness zones in the CES Section node 'label1'.

E1824

Section not found: 'label1'

CES section node 'label1' was not found when attempting to process the CES properties. This error should have been previously trapped, but check the connectivity and CES section data for this label.

E1825

At least two bank markers required for section id: 'label1'

At least one pair of left/right bank markers are required for each CES Section. Check section data for CES Section node 'label1'

E1827

Failed CES dll function call to FnAddInterpolate for interpolated section, cannot find upstream section for section id: 'label1'

The upstream CES section associated with node 'label1' was not found when attempting to process the CES properties. Check the connectivity and CES section data for this label.

E1828

Failed CES dll function call to FnAddInterpolate for interpolated section, cannot find downstream section for section id: 'label1'

The downstream CES section associated with node 'label1' was not found when attempting to process the CES properties. Check the connectivity and CES section data for this label.

E1830

Cannot find urban unit.

A connectivity error has occurred involving an Urban unit. Check connectivity for all Urban units.

E1831

This urban throughflow unit is not associated with an urban unit.

An urban throughflow unit must be associated with an urban unit. Check the urban units' connectivity.

E1832

The data store cannot accurately store the urban unit's number.

This error should not occur. Please Contact Flood Modeller Support.

Message

Description

E1900

Cannot allocate memory, status = n

A memory allocation error has occurred. This may be because the model is too large, or the machine's memory is low. If the problem persists, please Contact Flood Modeller Support, quoting the status error number, n.

E1926

CES units must be present either side of a chain of interpolates; labels involved are l1 and l2

If interpolating between CES Section units, ensure that a CES Section unit is both immediately before and after the consecutive INTERPOLATE units. Ensure that none of the INTERPOLATE units has a distance to next cross-section of zero.

E1926

Geometric conduits must be attached to another of the same type; labels involved are l1 and l2

A geometric conduit (e.g. circular, rectangular, arch or sprungarch) must be connected to one of the same type, though the dimesnions may change. If you need to change the type, insert a junction or other unit (e.g. loss) between the two, remembering that at such a break, the last unit before the junction, etc. must have a distance to next section of zero. Note that for the direct method, any change in dimensions along a reach will be ignored.

E1999

Error opening/closing file f1

An input/output error occurred with file f1. Check that the file in question is not read-only, and is not in use by another application. Check the Windows Task Manager for any processes that have crashed, but not properly stopped.

E1999

Can not have PMF Catchment Wetness Index flag with non-PMF profile

The flag for CWI has been set to 'PMFCW' for a non-PMF event in the FEH unit. Check the data file for the unit in question. Set the flag to 'FEHCW' to use standard FEH CWI, or 'OBSCW' and use an observed CWI.

E1999

Error in calculating ARF(5D)*EM-5D in CWI calculations for PMF

The storm duration for an FEH PMF must be less than 120 hours in order to perform the CWI calculation (values of EM-5D are only given up to 600hrs). Use a manual (observed) CWI value or a short storm duration.

E1999

Storm/catchment area must be positive

The catchment area was entered as zero or negative for an FEH/FSR unit, and caused an error in calculating the ARF. Note this error should have been previously trapped, and that storm area defaults to catchment area if entered as zero or negative.

E1999

Storm duration must be positive

A zero or negative storm duration was entered for the FEH unit. This is not allowed - check the input data for this unit.

E1999

Interpolate unit unacceptable as first data unit

An interpolate unit was specified as the first unit in the data file. This is not valid, since there is no previous unit from which to interpolate.

E1999

Replicate unit unacceptable as first data unit

A replicate unit was specified as the first unit in the data file. This is not valid, since there is no previous unit to replicate.

E1999

Invalid time/date format

An invalid date/time format was specified times entered in DATES format in an REBDY or GAUGE unit. The correct format for the time field is hh:mm; the correct format for the date field is dd/mm/yyyy. The time field is before the date field; both field widths are 10. Check data file input.

E1999

Storm duration (x hours) is too large/too small/not an odd integer multiple of dt

For a valid PMF calculation in an FEH unit, the storm duration must be between 1 minute and 600 hours. It must also be an odd integer multiple of the time interval in order for the PMF profile to be symmetrical, centred around a single peak value.

E1999

RPFLAG (f1) should be set to WINRP or SUMRP for PMF calculation

The rainfall profile flag (f1) in an FEH boundary unit must be set to 'SUMRP' or 'WINRP' for a PMF calculation. Check the data file; note that mixed case is not allowed.

E1999

SAAR (x) is less than the minimum allowed for PMF calculation

The SAAR value must be at least 500mm for an FEH PMF calculation - this is because the EM ratios are not specified for a SAAR value of less than 500mm.

E1999

Negative rainfall detected in PMF calculation.

A negative rainfall has been calculated for a time interval during an FEH PMF calculation. This should not occur - please contact Flood Modeller Support.

Message

Description

W2000

Poor model convergence

The model has failed to converge to a solution within the defined tolerances at at least one location for the current time step and may be the onset of instabilities within the model. Full details of the location and magnitude of the convergence error are found in the diagnostics (*.zzd) file; a greater description of their meanings is given in Convergence information. NB The error code number 2000 is only output to the diagnostics panel/information file (*.exy) and not the diagnostic log file (*.zzd).

W2001

Conduits with variable x-section are not permitted

The cross section of a conduit varies between adjacent sections. The direct steady method cannot solve this situation and assumes that the first (downstream-most) cross section applies for all sections in the reach. The pseudo time stepping steady method should be used if this approximation is unacceptable.

W2002

Conduits with variable bottom friction are not permitted

The bottom friction of a conduit varies between adjacent sections.  The direct steady method cannot solve this situation and assumes that the bottom friction for the first (downstream-most) section applies for all sections in the reach. The pseudo time stepping steady method should be used if this approximation is unacceptable.

W2003

Conduits with variable top friction are not permitted

The top friction of a conduit varies between adjacent sections.  The direct steady method cannot solve this situation and assumes that the top friction for the first (downstream-most) section applies for all sections in the reach. The pseudo time stepping steady method should be used if this approximation is unacceptable.

W2004

Conduits with variable friction forms are not permitted

The friction formula of a conduit varies between adjacent sections. The direct steady method cannot solve this situation and assumes that the friction formula for the first (downstream-most) section applies for all sections in the reach. The pseudo time stepping steady method should be used if this approximation is unacceptable.

W2005

Conduits with variable side friction are not permitted

The side friction of a conduit varies between adjacent sections.  The direct steady method cannot solve this situation and assumes that the side friction for the first (downstream-most) section applies for all sections in the reach. The pseudo time stepping steady method should be used if this approximation is unacceptable.

W2008

Water level below invert. label(node) = 'l'('n'); water level = 'x'

The water level has been calculated as below the conduit invert level and indicates that the solution is potentially unstable - the pseudo time stepping steady method will try to recover from this condition; however, if the problem persists then the following steps could be taken: check the data at 'label' for errors; improve the initial conditions; reduce the timestep or distance step; use the direct steady method or move from a previous steady result to the required flow/stage using an unsteady run. Also, check the invert level is consistent with the adjoining unit; insert a weir if appropriate.

W2010

Poor interpolation u/s of 'label' max u/s area of area1 ->  area2

The cross section area at the sections between which an INTERPOLATE section is required differs by a factor of two or more. Such large changes in area suggest that further survey data are necessary.

W2012

Flow over side spills not calculated

The direct steady method has detected flow was possible over the side spills listed in the diagnostics file (filename extension '.zzd'), but does not calculate such flow.

W2013

Very small change in flow resulting from correction (answer not found) at 'unit' 'label' q_reach = 'x' q_calc = 'y'

This indicates that the structure at 'label' is very insensitive to changes in head (obsolescent tidal drainage sluice units only). Check that the data for this unit are correct.

W2014

Unit attached to labels ''label1","label2'' running dry; water depth set to Dmin value of 'x' metres

The water level at a bernoulli loss in the direct method has been calculated as being below minimum depth. The water level has been reset to minimum depth; you are advised to check the reults and model schematisation in this area.

W2016

Steady file could not be opened, probably owing to file open to other user

Also check the read and write file attributes for the '.zzs' file.

W2017

Extra sections need to be added by the user

The direct steady method added additional sections to improve accuracy.  It is recommended that extra sections are also added to the datafile as listed in the diagnostics file (filename extension '.zzd').  The INTERPOLATE unit may be used to provide the additional data.

W2018

Indeterminate reaches have been found

The direct steady method located indeterminate reaches as listed in the diagnostics file (filename extension '.zzd'). The water levels and flows in these reaches are undetermined. This may be because zero flow has been imposed upstream of a structure.

W2019

Water level rose beyond the max level of section data. Solution computed assuming extra 3m wall for non-CES sections, or max depth x 1.5m for CES sections, at max breadth

Calculated water level exceeded the section data maximum and used the 'glass wall' vertical extension of dflood (or the CES multiplier for CES sections). The section labels at which this condition occurred are listed in the diagnostics file (filename extension '.zzd'). The survey data should be extended at these sections, particularly those with no spill attached (this is indicated inthe zzd file also).

W2020

Water level >3m above max level of section data for at least one section.

Calculated water level exceeded the section data maximum, including the 'glass wall' vertical extension of dflood (or the CES multiplier for CES sections). The section labels at which this condition occurred are listed in the diagnostics file (filename extension '.zzd'). The survey data should be extended at these sections. This may cause mass inconservancy at the sections involved.

W2021

Warning. The solution will be found with an accuracy of  'x' cm.   If you want to increase the accuracy for the direct method, decrease maximum tolerance at line number 2

A direct method tolerance of between 0.01m and 0.1m has been specified (General System Parameters, or "Direct Method Convergence Parameter" in the Parameters tab of the 1D Simulation interface). This indicates that the solution is not as accurate as is recommended. Note that a tolerance of greater than 0.1m will generate a fatal error.

W2023

Zero areas in Bernoulli Loss unit attached to labels ''label1'' and ''label2''. Zero flow will be imposed.

A zero area has been calculated at one or both nodes of the bernoulli loss unit - this usually indicates the water level is below the invert; zero flow is imposed at this unit.

W2024

'x' extra sections gave insufficient accuracy between 'label1' and 'label2'

The direct steady method was unable to obtain normal accuracy between 'label1' and 'label2'. The calculated upstream water level is not converging quickly enough. If this message occurs during the final iteration then the data at these labels may require attention.

W2025

Data error found in RNDSC gate not open at highest water depth label = 'label'

The direct steady method requires the gate to be open at the highest water depth.  The program may open the gate to 0.1m, although the user should alter the datafile as appropriate to the physical conditions. Obsolescent tidal drainage sluice units only.

W2026

CONDUIT and RIVER units should not be directly connected together; labels involved are 'label1' and 'label2'

One is advised to insert a junction, loss unit or appropriate structure between conduit section and river units. NB A river section attached to a geometric conduit unit will cause a fatal error.

W2027

No rules are currently valid for RULES unit associated with label 'label' at model time 'x' hrs.Unit will use previous setting of 'x'

Check that the rules applied cover all eventualities

W2031

'x' reservoir unit(s) in the network. Note that the flow from/to reservoirs is not calculated in the current version of the direct method

The unsteady or pseudo time stepping steady methods should be used if reservoirs are hydraulically significant features of the network with the current boundary conditions.

W2032

Water level outside channel boundary. label(node) = 'label'('n'); water level ='x'

The applied water level is below bed level or above the section maximum, and is probably an indication of model instability. This could be due to poor initial conditions or a data error. The error may be avoided by using a non-zero minimum water depth (General System Parameters, or via the Parameters tab on the 1D Simulation interface).

W2033

Warning; zero area calculated at node 'label'

A zero cross sectional area has been detected - check the RIVER data. If this message recurs several times and it seems to cause errors in the run then the minimum depth must be set to a positive value in the General System Parameters, or via the Parameters tab on the 1D Simulation interface.

W2034

N overbank spill unit(s) in the network. Note that no calculations are performed for overbank spills in the current version of the direct method

The unsteady or pseudo time stepping steady method should be used if spills are hydraulically significant features of the network with the current boundary conditions.

W2035

The HT boundary at 'label' is at the upstream end of a reach. This is not permitted

The direct steady method requires flow:time boundaries at the upstream end of reaches. Upstream stage time boundaries may cause indeterminacy and are not recommended in most cases.

W2036

The QH boundary at 'label' is at the upstream end of a reach. This is not permitted

The direct steady method requires flow:time boundaries at the upstream end of reaches.  Upstream flow head boundaries should not be used.

W2037

The qt boundary at 'label' is at the downstream end of a reach. This is not permitted

The direct steady method requires stage time or flow head boundaries at the downstream end of reaches.  Downstream flow time boundaries may cause indeterminacy and are not recommended in most cases.

W2039

no. of split parameters ('w') + no. of ht + qh boundaries ('x') does not equal no. of join parameters ('y') + no. of qt boundaries ('z')

The direct method cannot resolve the network. The cause of this condition is usually explained by the error messages displayed prior to this message. Often this is caused by in-line reservoirs in the model, or other configuration not conforming to the direct method rules. The direct method will not solve the parts of the network which are incorrectly defined and therefore the results must be checked for reaches not solved. Using the pseudo-timestepping steady state solver may be more appropriate.

W2040

Split estimates are wrong at the junction involving 'label'

The direct steady method requires that in initial conditions the total inflow and outflow at a confluence are equal. This situation should normally be resolved internally.

W2042

Illegal tidal constituent at line 'l'

There is an error in the tidal boundary data at line 'l'.  Check the datafile. See the Help file for a list of valid Tidal constituents.

W2043

Warning at line 'l'. Decreasing cross section distance

A decreasing cross-chainage value has been detected in the cross-section data. Check the data entry.

W2044

Above line'l': different values (+/- 20 %) for Mannings n encountered within one panel. Make sure L/R panel markers do not appear within an arch.

Differing values of Manning's n (of over 20%) have been entered within the same panel. You are normally advised to insert panel markers when the Manning's value changes. Note that panel markers may not appear within bridge arches.

W2045

Water level at or below reservoir invert. It has been reset to the invert 'x' m at label 'label'.

The water level within a reservoir has been reset to the invert level + minimum depth. This may be caused by poor initial conditions, or the reservoir outflow exceeding the reservoir volume. Reducing the timestep may assist the latter, as may setting the reservoir emptying factor to 1 (Low Flow Options tab on the 1D Simulation interface). Note that this message may appears a maximum of 50 times.

W2046

n lateral inflows unit(s) in the network; note that lateral inflows are set to zero in the current version of the direct method

Lateral inflows to Muskingum routing units are ignored in the direct method. Use the pseudo-timestepping steady method if preferred.

W2047

Non-rectangular control section used with notional weir. This is not available. A rectangular control section has been assumed.

An exponent exceeding 1.5 has been entered for the notional weir, indicating a non-rectangular control section. The calculation for critical depth does not take this into account.

W2048

Very small change in heads results n large change in flow during the run downstream water level close to the critical value. Results must be examined carefully. Label/s involved label1, label2

The downstream depth at a notional weir is within 5mm of critical depth, or (in steady timestepping mode only) the flow difference between successive iterations has exceeded 20%. Consequently, the results may lose accuracy.

W2050

Ratio between upstream and downstream areas exceeds 2.0 at at least one berlos. This may cause a lack of convergence and reduced accuracy. Check the unit data.

The upstream area in a Bernoulli loss unit is greater than double the downstream area. This may cause convergence problems due to oscillations between successive iterations; the user is advised to check the Bernoulli loss input data to verify the area inputs.

W2051

Estimated theta value is very large; this will be reset to (2*pi).

Theta is the parameter used in Suter's pump curve method, which lies in the range [0,2*pi). It is likely to be greater than 2*pi only in the case of rounding errors, so rounding it down to 2*pi is appropriate.

W2052

MSL is outside FSR range (0.27 to 239)

The MSL (main stream length) used in the FSR time-to-peak calculation is outside the valid range. However, the equations used will still calculate the Tp value based on the value entered (as long as it is positive). You are advised to check the input data.

W2053

Soil is outside FSR range (0 to 0.5)

The soil index used in the FSR percentage runoff (PR) calculation is outside the valid range. However, the equations used will still calculate the PR value based on the value entered (as long as it is between 0 and 1). You are advised to check the input data.

W2054

Urban fraction should not be > 0.808

The urban fraction used in FSR or the urban extent used in FEH (e.g. for PR, Tp calculations) is higher than the valid maximum (0.808 and 0.5, repsectively). However, the equations used will still use the value entered (as long as it is less than 1). You are advised to check the input data.

W2055

RSMD is outside FSR range (15.6 to 118)

The RSMD (Residual Soil Moisture Deficit) used in the FSR Tp calculations is outside the valid range. However, the equations used will still use the value entered (as long as it is greater than 10). You are advised to check the input data.

W2056

CWI is outside expected range (50 to 150)

The CWI (Catchment Wetness Index) used in the FSR/FEH calculations for baseflow and percentage runoff is outside the valid range. However, the equations used will still use the value entered. You are advised to check the input data.

W2057

Rainfall Profile duration is expected to be the storm duration

A user-input rainfall profile has been entered for an FSR/FEH unit, but the duration (number of items in profile * time interval) does not equal the input storm duration. However, the user-input profile will still be used in calculating the quick runoff hydrograph.

W2058

Model convergence criteria were not met for one or more timesteps during the run.

The model did not converge at one or more timesteps during the simulation. Details of when, and where the model was least convergent are given in the diagnostics (*.zzd) file. You are advised to check the model in these areas, and the extent of the non-convergence (e.g. DH and DQ values).

W2059

Catchment area is outside FSR range 0.038 km2 < fsr catchment area < 9868 km2

The catchment area in an FSR/FEH boundary (used in the peak flow, base flow and ARF calculations) is outside the valid range. However, the equations used will still use the value entered (if positive). You are advised to check the input data.

W2060

Conveyance decreases by x% at level y m, depth z m

A decreasing conveyance with increasing depth was encountered (if decreasing conveyance check is switched on); this may be caused by a large increase in width with a small increase in area in the cross section and can cause convergence problems near this depth. The problem may be alleviated by inserting a panel marker, if appropriate. One can also select the "Enforce increasing conveyance" option from the Low Flow Options tab on the 1D Simulation interface, which will set the conveyance to the previous value.

W2061

S1085 is outside FSR range (0.19 to 118)

The S1085 (10%-85% stream slope) value in an FSR boundary, used in the time-to-peak calculations, is outside the valid range. However, the equations used will still use the value entered (if positive). You are advised to check the input data.

Message

Description

W2100

Invalid value given for modular limit; internally calculated value will be used during run.

A modular limit value of less than 0 or greater than 1 has been entered for a round-nosed or crump weir. The program will calculate the [variable] value of modular limit, rather than using a fixed value.

W2201

Friction law not specified correctly in bridge attached to labels label1, label2. Friction law assumed to be Mannings

The keyword on the 4th line of a bridge unit must be 'MANNING' (case sensitive). No other friction law is currently valid, and Manning's equation will be used. Check the data file.

W2202

Bridge calibration factor set to zero. Bridge attached to labels label1, label2 will have no effect.

The bridge calibration factor has been set to zero. Thus no headloss will be applied at this bridge, and therefore the bridge has no effect.

W2203

There is insignificant flow through the arches at USBPR bridge downstream of node label1. You should check bridge and culvert data or consider modelling the culverts as separate units.

The flow through the flood relief culverts is significantly higher than that through the bridge arches, and the flow through the arches may be misrepresented. You are advised to check the input data/dimensions of the arches and culverts; if the flow through the culverts is expected to be large, it may be preferable to model them separately.

W2204

Bridge downstream of label1 is surcharged. Afflux calculation may be inaccurate.

The calculated water level at a USBPR bridge unit has exceeded the bridge soffit. The method is not validated for surcharged bridges, and therefore may not be accurate. You may wish to consider modelling the bridge as an orifice.

W2205

Extrapolating base curves, base coefficient may not be reliable. Blockage ratio = m at bridge connected to labels label1, label2

The blockage ratio, m, in a USBPR bridge unit is less than 0.2. The USBPR method does not provide for such blockage ratios and the base coefficient, Kb, is extrapolated from the published values.

W2206

Extrapolating pier curves, pier coefficient may not be reliable Pier ratio J = j. Using del K (max)= 0.4 at bridge connected to labels label1, label2

The pier coefficient in a USBPR bridge unit is greater than 0.4 and has been reset to its maximum, 0.4.

W2207

Extrapolating pier sigma curves, sigma coefficient may not be reliable Using sigma (min)= 0.6 at bridge connected to labels label1, label2.

The blockage ratio in a USBPR bridge unit is less than 0.4 for a positive pier ratio, j. The pier sigma coefficient has been reset to its minimum of 0.6.

W2208

Extrapolating skew curves, skew coefficient may not be reliable. Blockage ratio = m at bridge connected to labels label1, label2.

The blockage ratio, m, in a USBPR bridge unit is less than 0.3 for a non-zero skew. The USBPR method does not provide skew coefficient values for such blockage ratios, which have therefore been extrapolated from the published values.

W2209

Failed to load convey.dll.

W2211

Failed to free memory in CES dll.

W2212

CES dll magic number error.

W2213

CES dll version error.

W2214

Failed to set Flood Modeller in CES.

W2215

Bad gauge data at time x hrs. Gauge unit at label1 disabled/record skipped.

The data for a gauge unit has fallen outside the user-defined limits. Depending on the strategy applied on such an occurrence (STRICT or PARTIAL), the whole gauge updating unit has been disabled, or the bad record skipped.

W2216

Gauge limit "PARTIAL" incompatible with "GRADIENT" option. "STRICT" limit enforcement applied

For a gauge unit, PARTIAL correction (i.e. interpolation of bad data) is not valid if the limits of validity are being applied to a gradient. Thus, if non-conformant data is found with the GRADIENT option, the gauge unit is disabled.

W2217

No method file specified for gauge unit. Using default parameters :

The method file used to specify the gauge parameters has not been specified - this should be entered in the unit form; otherwise, the default parameters as listed will be used.

W2229

Value of trash screen height is set to 0; areas will be calculated using piezometric head.

A trash screen is being used for a culvert inlet unit, but its maximum height has not been set. The velocity through the trash screen will be calculated using the piezometric head, which may be significantly greater than the trash screen soffit and therefore give unrealistically low velocities (as opposed to using the true area of the trash screen).

W2235

Variable Percentage Runoff Flag is expected to be FIXED or VARIABLE

The PRFLAG keyword in an FSR/FEH unit must either be 'FIXED' or 'VARIABLE' (case-sensitive). A FIXED percentage runoff will be used by default. Check data file.

W2236

Optimum number of internal calculation points in the reach is n. The maximum allowed number is 100. You could try increasing the timestep or decreasing the reach length.

The absolute maximum number of internal calculation points for a Muskingum unit is 100; either a user-entered maximum, or the optimum number of subnodes exceeds this. If the latter, a shorter reach length will lead to a lesser optimal number of subnodes.

W2237

MUSK-RSEC data error. Reference flow and bankful flow proportion are both zero. Setting bankful flow proportion to 1.0 and using bankful flow to calculate distance step.

For the Muskingum Routing Section (MUSK-RSEC) unit, the number of subintervals is calculated using bankfull proportion or maximum discharge. At least one of these must be specified (and positive).

W2238

Warning: panel at offset x has very small width

The panel beginning at a cross-chainage of x is less than 1mm wide. Check the input data.

W2260

WARNING: for culvert bend losses Loss coefficient should be less than 0.5. Current value is x

The recommended maximum k-value for a culvert bend loss is 0.5. A maximum value of 3 is allowed.

W2261

WARNING: Backflow encountered at culvert bend or loss unit.

Reverse flow has been encountered at a culvert bend or loss unit. This may indicate the onset of an instability.

W2262

WARNING: Backflow encountered CULVERT OUTLET unit.

Reverse flow has been encountered at a culvert outlet loss unit. This may indicate the onset of an instability. The unit may also be inappropriate for reverse flow.

W2263

WARNING: Backflow encountered at CULVERT INLET unit; outlet control equations will be imposed.

Reverse flow has been encountered at a culvert inlet loss unit. This may indicate the onset of an instability. The unit may also be inappropriate for reverse flow.

W2264

Level below culvert invert; resetting depth to dmin.

The level upstream of a culvert bend unit has been calculated as below the culvert inlet. It has been reset to minimum depth. This may indicate potential instabilities in the model.

W2266

Level below culvert invert; resetting depth to dmin.

The level upstream of a culvert outlet unit has been calculated as below the culvert inlet. It has been reset to minimum depth. This may indicate potential instabilities in the model.

W2267

No sub/supercritical depth could be found at node label1

No bounds could be found for supercritical or subcritical depth at the section, therefore not being able to guarantee finding a solution for critical depth. Critical depth may be required for culvert inlet losses, the transcritical solver, or the normal/critical depth boundary.

W2268

d/s end of a reach is neither a junction, structure, loss nor a boundary. Direct supercritical method cannot yet handle this; label involved: label1

An error was found in applying the supercritical depth calculation in a downstream direction for the direct method - the unit at the downstream end of a reach was not valid - check connectivity.

W2271

Failed to find a minimum of the energy function at label label1

A solution could not be found for the energy equation at node label1. The energy equation is used in the direct method transcritical solver at a subcritical (upstream) to supercritical (downstream) transition

W2272

Energy equation failed to converge to a subcritical/supercritical soln at node a energy equation failed to converge to a subcritical soln at node label1

The solution to the energy equation did not converge at node label1. The energy equation is used in the direct method transcritical solver at a subcritical (upstream) to supercritical (downstream) transition

W2273

Defaulting to critical depth at node label1

During the supercritical part of a reach, the direct method transcritical solver calculated a depth that was either above critical depth or below bed/invert level. The depth has been reset to critical depth by default.

W2274

Water level in Bernoulli loss unit is lower than or the same as the previous level

The water levels in the Bernoulli Loss unit input table are not in ascending order. Check input data.

W2274

Bernoulli loss area x sq m is smaller than the previous area y sq m

The areas in the Bernoulli Loss unit input table are not in ascending order. This may cause inconsistencies in interpolating areas during the computational phase. Check input data.

W2275

Two levels have zero upstream area Upstream area corresponding to level x m has been increased to 0.001 sq m

Two consecutive areas in the Bernoulli Loss unit input table have been entered as zero. This may cause inconsistencies during the computational phase - the second area has been increased to 0.001sq m. Check input data.

W2276

Water level set to adjacent lowest bed level+0.01:x

The water level upstream of a bridge unit calculated by the Direct Method was below the bed level - this has been reset to x, 1cm above bed level.

W2277

This is the last appearance of a message of the type: conduits are not permitted

A maximum of 50 warnings are output relating to variable parameters not being permitted within a conduit reach for the Direct Method.

W2278

Zero calibration coefficient: no flow

A calibration coefficient (multiplicative factor) has been set to zero for the crump or flat-v weir unit; therefore zero flow will be imposed at this unit.

W2279

Reference velocity exceeds 3 m/s at at least one berlos. This may cause a lack of convergence and reduced accuracy. Check the unit data.

The upstream velocity (calculated as discharge/[reference area]) in a Bernoulli loss unit is greater than 3m/s. The user is advised to check the Bernoulli loss input data to verify the area inputs, and hence the feasibility of this velocity.

W2280

Estimated theta value is negative; this will be reset to zero.

Theta is the parameter used in Suter's pump curve method, which lies in the range (0,2*pi). It is likely to be less than zero only in the case of rounding errors, so rounding it up to zero is appropriate.

W2281

No flow possible with zero coefficient

A calibration coefficient (multiplicative factor) has been set to zero for the obsolescent tidal drainage sluice unit; therefore zero flow will be imposed at this unit.

W2282

Minimum/initial timestep has been reduced/increased to the ...

An inconsistency was entered in the adaptive timestepping times. The hierarchy must follow: minimum timestep <= initial timestep <=save interval. The timesteps have been adjusted accordingly as described.

W2283

Conduit section should be entered anti-clockwise from invert centre line. Section has been reversed

A conduit section unit must have the data entered from the centre of the invert, in an anti-clockwise direction, to the centre of the soffit. If the second cross-chainage value lies to the left of the centre, this and all subsequent cross-chainage values have been reversed; if the soffit level is lower than the invert level, the data is assumed to have been entered backwards, and the order of all input points has been reversed. You are advised to check the input data.

W2286

Reservoir/Pond area x sq m is smaller than the previous area y sq m

The areas in a reservoir or pond unit should be entered in ascending order. Otherwise, inconsistencies in interpolating areas/volumes may occur. Check input data.

W2287

Two levels have zero area. Area corresponding to level x m has been increased to 0.001 sq m

Two consecutive areas in the Reservoir or Pond unit input table have been entered as zero. This may cause inconsistencies during the computational phase - the second area has been increased to 0.001sq m. Check input data.

W2288

Warning: Initial water levels upstream of RESERVOIR/POND unit are not all equal. Initial level of x m will be used.

The initial conditions file contains different levels for one or more nodes in a Reservoir or Pond unit. The initial water level used is that specified for the first node in the unit.

W2289

Discharge coefficient set to zero

The coefficient of discharge, Cd, has been set to zero for the sluice or round-nosed weir unit; therefore zero flow will be imposed at this unit.

W2290

Opening is zero - no flow possible

The gate opening has been set to zero for the obsolescent tidal drainage sluice unit; therefore zero flow will be imposed at this unit.

W2291

Warning: Initial water level at label l1 of x m is higher than the crest of the SPILL. This may cause initial instabilities.

One is normally advised to begin simulations with no flow over lateral spills, since otherwise this may lead to initial instabilities. However, it is acknowledged that this may not always be practical, e.g. for continuous simulation models. In such cases, it is imperative that good initial conditions are provided, and use of the hot-start functionality is recommended.

W2292

Failed to converge to normal depth at node l1; normal depth calculated x; slope y; Friction slope z.

A solution could not be found within the required accuracy (<1mm) for normal depth at a NCDBDY unit. The final parameters used in equation are supplied further information. If is calculated as being below bed level, it reset to level.

W2293

Linear interpolation with rainfall data/DEPTH specification not allowed. BAR data format enforced.

Linear interpolation of rainfall data is not valid - one must specify rainfall data as bar-chart type.

W2294

Crump, Flat-V weir at l1 is not connected at u/s [d/s] node to a river section. Velocity heads may be calculated incorrectly. Use of remote nodes is recommended.

The Crump Weir and Flat-V Weir units both use a discharge relationship based on total head. Therefore, velocities, and hence areas need to be obtained. These are normally obtained from the adjoining unit; however, if this is not a channel unit, this is not possible, unless remote nodes (labels 3 and 4) are specified as channel units, from which to obtain the upstream and downstream areas respectively.

W2295

5D (5×storm duration) of hours is greater than 192hrs. Seasonal PMPs have been extrapolated from FEH table and may be inaccurate

The Catchment Wetness Index (CWI) calculation for a PMP involves estimated antecedent rainfall of a duration of 5D. The FEH rainfall tables are provided for durations of up to 192 hours, therefore anything beyond this is extrapolated from the values given.

W2296

Error in rule X. WARNING: string Y can be interpreted as a numerical value and as a node label. Using numerical value of Z.

When using logical rules units, it is not permitted to reference node labels that can be interpreted as numbers, since these are often read as numeric values, and not recognised as a node label. As well as labels such as '1000', labels containing a single 'D' or 'E', but otherwise numeric, such as '20D400' may be interpreted as [exponentiated] numbers.

W2297

Date/time set in Tidal Boundary unit used in preference to those of the simulation event

It is recommended that a Tidal Boundary uses an event-based time, rather than that specified in the data file. However, this can be overridden with the data file entered date/time by leaving the appropriate check box unchecked in the unit form. The user should verify that the correct date/time is being used.

W2298

Data interval is less than one minute; PMP ratios held at the 1-min value. PMPs may be inaccurate - a longer data interval is recommended.

The PMP calculation involves estimated rainfall at each data interval, using the FEH EM ratio tables. The minimum duration in these tables is 1-minute, and for shorter durations these values are extrapolated from the values given.

W2299

Storm duration (x hours) is not an approximate integer multiple of dt (y hours). Using nearest integer multiple.

The storm duration for a PMP must be an odd integer multiple of the data interval, to allow for a symmetrical storm profile. If the storm duration is not an integer multiple (to within 0.05hrs) of the data interval, it is rounded up to the nearest integer multiple. If then this turns out to be an even multiple, a fatal error is generated.

W2300

Areal reduction factor equation for short durations (0.25-0.5hr) called. Duration = x hours. PMF results may be inaccurate.

The areal reduction factor (ARF) for a PMF is required at each time interval, which may result in a short effective storm duration. The usual equation (from Keers & Westcott) is not valid for durations less than 0.5 hours, so the ARF for shorter durations is interpreted from the graph in FEH Vol 4 Fig 3.4.

W2301

The adaptive timestepping parameter avitr should be greater than minitr

The adaptive timestepping parameter avitr denotes the maximum number of iterations at which convergence is achieved before the method tries increasing the timestep. If avitr is less than minitr, a solution is never achieved in less than avitr iterations, and therefore the timestep will never increase.

W2302

Time to peak, tp, is not an integer multiple of the data interval. The unit hydrograph peak, Up, may possibly be significantly reduced. You are advised to check the U-H data and consider a user-input (observed) time to peak if appropriate.

For the triangular unit hydrograph (UH), convolution of rainfall with the UH may miss the peak of the unit hydrograph if the peak occurs between two data intervals and lead to underestimation of the peak flow. This can be rectified by selecting a time-to-peak that coincides with a data interval. The modeller is advised to check the sensitivity to the time-to-peak. Note that the s-curve method used in ReFH also alleviates this problem.

W2313

Zero modular limit

The modular limit in the manhole unit has been set to zero. This may give unrealistic results.

W2314

Modular limit set to unity or greater. Flow will always be modular

The modular limit in the manhole unit was set greater than or equal to 1. This will force modular flow for the outlet.

W2315

Negative loss coefficient entered - this will be reset to zero

The loss coefficient in a manhole unit was set to zero; zero headloss will therefore be applied.

W2317

Downstream flow area in floodplain section constrained by modular limit or downstream constraint factor.

In a floodplain section unit, the downstream water level is below crest level or only slightly above. The downstream area used in determining friction flow has therefore been replaced by a factor (downstream constraint, or modular limit if the former not set) of the upstream flow area.

W2318

Initial adaptive timestep not read from file - using ief value.

The initial adaptive timestep was set to be read from the adaptive timestepping file but could not be found/read. The simulation has therefore defaulted to using the value set in the 1D Simulation File (*.ief).

W2319

Downstream constraining factor not set for floodplain section - using modular limit

The downstream constraint was not set in a floodplain section unit. For low downstream water levels, the downstream area used in determining friction flow has a lower limit of modular limit × upstream flow area. It is recommended that the downstream constraint factor is set.

W2320

Reservoir updating unit not connected to a reservoir.

An updating (gauge) unit with ’r;Reservoir’ option set is not connected to a reservoir unit. The updating unit will therefore be ignored.

W2321

Conduit slot dimensions (dh or height) calculated or entered incorrectly.

When using a conduit slot, an invalid dimension for the slot has been calculated (or entered). This has been replaced by a default value as stated in the specific diagnostic message.

W2322

Failed to read event data

An error occurred opening/reading the 1D event data file (*.ied). Data in this file has been ignored. To trigger a fatal error in such instances, insert the line FailOnIEDError=1 in the formsed.ini file ([Preferences] section) This .ini file is installed to C:\Users\<user>\AppData\Roaming\Flood Modeller (or  <user>\AppData\Roaming\ Flood Modeller ).

W2323

Unrealistic density input

A density value of less than 900kg/m3 or greater than 1100kg/m3 has been set in a River section unit. The value has been reset to 1000kg/m3.

W2531

Cannot find an upstream condition from which to start supercritical integration

The direct method transcritical solver requires a prescribed upstream water level if the upstream end of a reach is supercritical. This can be specified if the upstream boundary is a QTBDY by entering a third column for stage, field columns 21-30. This requires editing of the data file in a text editor.

W2532

Model start time is NOT t=0. Hydrograph start time IS t=0

This provides the user with a warning that the model simulation start time is not zero, but the hydrological boundary-generated hydrograph does start at t=0. This may be as required, but may also mean that the start of the hydrological boundary is not as required. The modeller is advised to use the time delay functionality in the hydrological boundary or start the simulation at t=0 if the hydrograph is required to coincide with the model start time.

W2533

Warning: Volumes not calculated/output for Muskingum sections in file

The volume output option has been selected, but the model contains Muskingum sections. Volumes are not calculated for Muskingum units, so the total volume or mass balance may therefore be misrepresented.

W2534

Errors occurred opening/writing to file f1

Check that the file name f1 is not opened by another application, and also that read/write access is allowed for the current user.

W2535

c0 scaling factor input error.

The c0 scaling factor (smoothing factor) is used in Muskingum units to provide a minimum wavespeed, to aid stability at low flows. The value entered is as a proportion of maximum in-bank wavespeed and must be between 0 and 1. It is not recommended to exceed 0.5.

Message

Description

N3002

Very small change in heads results in large change in flow at u1 l1.

A large rate of change of flow with respect to head was detected in the direct method at unit u1, label l1. This indicates that the results may be very sensitive to head.

N3003

Percentage runoff calculated as negative value therefore set to zero

The calculation of percentage runoff (PR) in FSR/FEH resulted in a negative PR value, which was reset to zero. This could be caused by a small CWI value or low precipitation.

N3006

NOTE: End of backflow at CULVERT INLET unit.

This indicates the time at which backflow stopped in a culvert inlet unit. This should be used in conjunction with warning W2263. The modeller should also consider the frequency and duration this occurrence, and whether backflow is appropriate at the time. This could indicate model instability.

N3007

NOTE: End of backflow at CULVERT OUTLET unit

This indicates the time at which backflow stopped in a culvert outlet unit. This should be used in conjunction with warning W2262. The modeller should also consider the frequency and duration this occurrence, and whether backflow is appropriate at the time. This could indicate model instability.

N3010

Simplified method used to compute solution at one or more sections

The convective acceleration term in the momentum equation was simplified due to a high Froude number (greater than the lower Froude number trigger point) being attained. This generally results in a hydraulic jump being smoothed out over a number of nodes, and may therefore result in a less accurate solution at high Froude numbers. The user should consider using the Direct Method Transcritical Solver, if an accurate steady-state solution is required.

N3012

Zero flow beyond l1 (osetqh)

Zero flow has been applied by the Direct Method at node label l1 and all nodes upstream of this

N3013

Transcritical point(s) occurred at one or more locations Any additional recommended sections tabulated above may be overstated

The direct method transcritical solver detected the listed transcritical locations and type. Additional sections involving these nodes may have been recommended in an earlier message, although this recommendation may be superseded by the detection of the transcritical point.

N3014

EVENT DATA FILE READ FAILED. See top of diagnostics (*.zzd) file for more info

A read error occurred for the event data (*.ied) file(s) specified earlier in the diagnostics (*.zzd) file. Check that the *.ied file exists and is not locked out by another application. The model should be rerun to take into account this event data.

N3015

Simulation event date/time overrides that set in Tidal Boundary unit

It is recommended that a Tidal Boundary uses an event-based time, rather than that specified in the data file. However, this can be overridden with the data file entered date/time by leaving the appropriate check box unchecked in the unit form. The user should verify that the correct date/time is being used.

N3016

Tidal Boundary unit used but no event date/time exists. You are advised to check that the date/time in the TIDBDY unit is appropriate.

No valid event-based time was specified (i.e. absolute time used) in the 1D Simulation/*.ief file. The tidal boundary is therefore using the date/time specified in the data file. The user should verify that the correct date/time is being used.

N3017

Tidal boundary used with the direct method. You are advised to ensure that the tide is in ebb to avoid reverse flow.

The direct method will not work with reverse flow, and will be driven by the level in the tidal boundary. This could result in a very high head being applied at the downstream end, leading to high water levels upstream (if practically, reverse flow would be applied at the time). Steady-state tidal models are not recommended.

N3018

2D Input Data check completed - simulation option not chosen Program execution terminated normally.

The TUFLOW link was chosen with the 2d data check option. The simulation was not run, but terminated after the 2d check phase.

N3019

Note: A user-input PMF time to peak is assumed to already contain the 0.67 adjustment factor

The time-to-peak (Tp) for an FEH PMF simulation is adjusted from the instantaneous UH Tp by a factor of 0.67, when calculated. However, if specifying a user-input Tp, the user should take this into account before entering the value (i.e. the software does not apply the adjustment factor to an Observed Tp).

N3025

Minimum flow has been applied at this boundary

A flow-time boundary (QTBDY) has the minimum flow value set, which has been invoked due to the input flow value falling below this.

N3026

Initial adaptive timestep read from input file

The setting for the initial timestep for an adaptive timestepping run has been obtained from the adaptive timestep file, as opposed to the event file.

N3027

2d timestep read from tcf file

The TUFLOW timestep has been read from the TUFLOW control file (*.tcf) and not the 1D Simulation File (*.ief). Setting the 2d timestep to a negative value in the 1D Simulation File allows this.

N3028

Data points omitted from deactivated section areas

The deactivation markers were set on one or more river section units. Any data points falling outside these deactivation markers are ignored.

N3029

Duplicated units found

The same unit(s) were found in both the event data file(s) (*.ied) and the main data file (*.dat). The latter (and any second occurrence in the *.ied file) are ignored.