Full Equations Utilities (FEQUTL) Model for the Approximation of Hydraulic Characteristics of Open Channels and Control Structures During Unsteady Flow

U.S. GEOLOGICAL SURVEY WATER-RESOURCES INVESTIGATIONS REPORT 97-4037

*ERR:nn* MESSAGES

FEQUTL contains a fairly extensive set of error messages to detect errors in the input as early as possible. However, errors could be encountered that are not yet detected in the FEQUTL software. When previously undetected errors are identified, the program code will be changed so that these errors may be detected before computational problems or incorrect results are caused. However, it is possible to specify the input so that no errors are detected in FEQUTL computations and still the input is improperly defined through some error on the part of the user. As a simple example, the offsets utilized for the boundary points on a cross section may be given in a valid form and also may specify a valid cross section. However, the cross section may not be the correct size because an incorrect map scale was applied to the measurements. This error cannot be detected in FEQUTL computations because the input is valid, but incorrect for the application. Thus, there are three types of errors possible: an error that can be detected in FEQUTL computations and is detected; an error that could have been detected in FEQUTL computations, but no code for the detection is available; and an error that, by its nature, cannot be detected at any time in FEQUTL computations. Over time as the model is applied, the number of errors of the first type will increase and the number of errors of the second type will decrease. However, the number of errors of the third type will stay the same.

The error messages are given in numerical order in the following list. Gaps may be present in the order as changes are made so that the absence of a numbered message does not necessarily imply that some message has been omitted. Furthermore, the order of numbering is arbitrary.

In many cases the message includes numbers and, in a few cases, character strings. Values of numbers and character strings will depend on the specific occurrence of the error. The positions of these occurrence-dependent values are denoted by 'nn' for an integer number, 'ff' for a floating point number (one containing a decimal point or in the floating point format), and 'aa' for a character string.

*ERR:500*CONVERSION ERROR IN LINE:

A line of input that cannot be converted from character form to internal form has been detected. This can result from many user errors. An input field that should contain a number probably included one or more characters. Therefore, the conversion cannot be made. This can result from typing the letter 'O' instead of the digit '0'. An input line may have been omitted so that the wrong line of input was read. The values on the line may be in the wrong columns so that an input field that should contain a number contains an alphabetic or special character that should not appear. Also, all the input items may be numbers, but an error in spacing the input places two decimal points in one field.

*ERR:501* UNKNOWN COMMAND.

A command has been read that cannot be found in the current list of commands. The current list of commands is defined by the standard header information (section 5.1) that appears at the head of each input to FEQUTL. It might be that the current version of FEQUTL supports the command invoked, but the header information is from a previous version of FEQUTL that does not support the command. The header information must be corrected and the model run attempted again. The command could have been mistyped and, therefore, could not be found.

*ERR:502* INVALID VALUES FOR NRZERO OR DZLIM BOTH MUST BE > 0.0

The input values for NRZERO, the depth for the near-zero values, and DZLIM, the maximum change in argument, both applying to cross-section tables only, must be > 0 (see section 5.1). At least one of the values has been given as zero.

*ERR:503* TOO MANY COMMANDS IN SYSTEM FILE. LIMIT= nn

More commands have appeared in the header to the input than are allowed in FEQUTL. The parameter MAXCMD must be increased in the INCLUDE file ARSIZE.PRM (appendix 2) and FEQUTL must be recompiled and linked to allow for more commands.

*ERR:504* NUMBER OF SUBSECTIONS= nn > nn

The number of subsections for a cross-section specification has exceeded the number allowed in FEQUTL. The parameter PMXSUB must be changed in the INCLUDE file ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked to permit more subsections.

*ERR:505* SUBSECTION NUMBER TOO LARGE AT OFFSET= ff

A line segment of the cross-section boundary has been assigned to a subsection number, which is larger than the number of subsections given earlier in the input when the Manning's n values were given (sections 5.8-5.9-5.10). Thus, the cross section cannot be processed because the line segment has no assigned value of n.

*ERR:506* ONLY ONE POINT GIVEN ON BOUNDARY OF THE CROSS SECTION.

At a minimum, two points must be given on the boundary of the cross section before the cross section is defined. A mistake has likely been made in a subsection number such that the input of the cross section is determined to be complete in FEQUTL computations when it is not complete (see sections 5.8-5.9-5.10).

*ERR:507* NUMBER OF POINTS IN CROSS SECTION > nn

The number of points given on a cross section is larger than the current internal maximum allowed in FEQUTL. The size of the parameter PMXPNT must be increased in the INCLUDE file ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked.

*ERR:508* SECTION VIOLATES MONOTONICITY AT OFFSET= ff

The cross-section offsets should be nondecreasing and an offset has been detected that violates this condition. Either the user specification for checking monotonicity of offsets is incorrect or an error in the cross section is present.

*ERR:509* TABLE# < 0 OR TABLE# > nn

A function-table number is out of range. If the upper range is too small, the parameter PMXTAB in the INCLUDE file ARSIZE.PRM (appendix 2) should be changed to a new value, and FEQUTL must be recompiled and linked.

*ERR:510* DUPLICATE TABLE NUMBER.

A table number already in use has been detected. The table numbers should be changed so that each table in a run of FEQUTL is unique.

*ERR:511* UPSTREAM CROSS SECTION MISSING FOR BRIDGE

An upstream cross section must be present for execution of the bridge routine, and no upstream cross section has been read. The last cross section processed, before the bridge routine is called, should be specified as the upstream cross section for the bridge. This bridge-loss method is no longer supported in FEQUTL. It remains in the code for the benefit of users with stream-system models developed for versions of the FEQUTL code prior to version 4.0. These users are encouraged to revise the models to apply the WSPRO (Shearman, 1990) bridge routines (section 4.1).

*ERR:512* DOWNSTREAM CROSS SECTION MISSING FOR BRIDGE

A downstream cross section must be present for execution of the bridge routine, and no downstream cross section has been read. The downstream cross section for the bridge should appear in the input to FEQUTL before the input of the upstream cross section for the bridge. The upstream cross section for the bridge should appear in the input to FEQUTL immediately before the input for the bridge. This bridge-loss method is no longer supported in FEQUTL. It remains in the code for the benefit of users with stream-system models developed for versions of the FEQUTL code prior to version 4.0. These users are encouraged to revise the models to apply the WSPRO (Shearman, 1990) bridge routines (section 4.1).

*ERR:513* BASE CURVE# > 3 OR < 1.

In the Bureau of Public Roads (Bradley, 1970) bridge-loss method, three base curves are available for the loss coefficient. A base curve number outside this range has been detected. This bridge-loss method is no longer supported in FEQUTL. It remains in the code for the benefit of users with stream-system models developed for versions of the FEQUTL code prior to version 4.0. These users are encouraged to revise the models to apply the WSPRO (Shearman, 1990) bridge routines (section 4.1).

*ERR:514* PIER TYPE < 0 OR > 8.

The pier type for the Bureau of Public Roads (Bradley, 1970) bridge-loss method must be in the given range. A pier type has been found that is outside this range. This bridge-loss method is no longer supported in FEQUTL. It remains in the code for the benefit of users with stream-system models developed for versions of the FEQUTL code prior to version 4.0. These users are encouraged to revise the models to apply the WSPRO (Shearman, 1990) bridge routines (section 4.1).

*ERR:515* NUMBER OF ENTRIES IN PIER NUMBER-WIDTH TABLE > nn

The number of entries in the pier description in the Bureau of Public Roads (Bradley, 1970) bridge-loss method is too large. The current limit is 25 and cannot easily be changed. This bridge-loss method is no longer supported in FEQUTL. It remains in the code for the benefit of users with stream-system models developed for versions of the FEQUTL code prior to version 4.0. These users are encouraged to revise the models to apply the WSPRO (Shearman, 1990) bridge routines (section 4.1).

*ERR:516* ELEVATION FOR PIER NUMBER-WIDTH TABLE IS DECREASING AT:ff

The elevation in the pier description in the Bureau of Public Roads (Bradley, 1970) bridge-loss method is decreasing and is, therefore, invalid. This bridge-loss method is no longer supported in FEQUTL. It remains in the code for the benefit of users with stream-system models developed for versions of the FEQUTL code prior to version 4.0. These users are encouraged to revise the models to apply the WSPRO (Shearman, 1990) bridge routines (section 4.1).

*ERR:517* ONLY TYPE RDFLOW IS VALID FOR A BRIDGE

Only the bridge option RDFLOW is supported for the Bureau of Public Roads (Bradley, 1970) method. If no flow over the roadway is possible, the top of road elevation should be made so large that water will never overtop the road, and flow tables that yield zero flow should be input. This bridge-loss method is no longer supported in FEQUTL. It remains in the code for the benefit of users with stream-system models developed for versions of the FEQUTL code prior to version 4.0. These users are encouraged to revise the models to apply the WSPRO (Shearman, 1990) bridge routines (section 4.1).

*ERR:518* SUBSET AND SECTION ARE DISJOINT

A subset from a cross section has been specified, either in the bridge computations or in a floodway specification. The subset is such that it is not contained within the cross section. Therefore, the subset cannot be computed. The specification of the subset should be checked for the location of the center of the bridge opening relative to the upstream cross section. The Bureau of Public Roads (Bradley, 1970) bridge-loss method is no longer supported in FEQUTL. It remains in the code for the benefit of users with stream-system models developed for versions of the FEQUTL code prior to version 4.0. These users are encouraged to revise the models to apply the WSPRO (Shearman, 1990) bridge routines (section 4.1).

*ERR:519* EXPECTED Q CARD BUT FOUND:aa

A printer output file from WSPRO should contain a Q card--that is, a line specifying the flow. The Q card was not found in the FEQUTL computations; instead, the given string was found. A problem may be in WSPROT14 (section 5.22): the version of WSPRO utilized could have changed the output from the pattern utilized in the version of WSPRO on which command WSPROT14 is based, or the printer file may be incomplete.

*ERR:520* NEGATIVE DEPTH= ff AT NORMAL-FLOW SECTION.

A water-surface elevation given in the WSPROQZ command (section 5.21) is below the bottom of the normal-flow section. Either the normal-flow section contains an invalid bottom elevation or the water-surface elevation is in error.

*ERR:521* NUMBER OF SUBAREAS= nn INCONSISTENT WITH NUMBER OF n VALUES=nn

The number of subareas and the number of n values must agree in a WSPRO input. A disagreement between these two values has been found in WSPROX (section 5.23).

*ERR:522* NUMBER OF n VALUES=nn INCONSISTENT WITH NUMBER OF BREAKPOINTS ON ND.

The number of n values must be compatible with the number of breakpoints on the ND record giving the variation of roughness with water level in the WSPROX command (section 5.23). In this case, the numbers disagree.

*ERR:523* NO GR CARDS FOUND FOLLOWING XT CARD.

No ground points have been given after a template section header in the WSPROX command (section 5.23). The template section is then undefined.

*ERR:524* THERE ARE nn ITEMS FOR FLOW-LINE DATA. ONLY 1, 3, OR 5 ITEMS ARE VALID.

An invalid number of flow-line data items have been detected in WSPROX (section 5.23). An odd number of items should always be input.

*ERR:525* SPACE FOR ELEVATION ARGUMENTS EXHAUSTED

arguments are added in FEQUTL to those defined by the unique breakpoint elevations, which are found in the cross-section specification in order to improve the accuracy of the conveyance estimation. In this process, the space allocated for these arguments has been filled to capacity. The space allocated for arguments is the same as the number of points in the cross section. Therefore, the PARAMETER pmxpnt must be increased in the INCLUDE file ARSIZE.PRM (appendix 2) and FEQUTL must be recompiled and linked.

*ERR:526* NEGATIVE DEPTH= ff AT CRITICAL-FLOW SECTION.

In the command WSPROQZ (section 5.21), the elevation derived for the water surface in the critical-flow section has been computed below the bottom of the critical-flow section. The elevation of the bottom of the critical-flow section could be in error. The offset from the water-surface elevation or the water-surface elevation also could be in error.

*ERR:527* FLOW UNDEFINED AT DNS ELEVATION= ff

In the command WSPROQZ (section 5.21), the flow is undefined. Probably a result of previous errors already reported. A defined flow must be present, and no flows have been read.

*ERR:528* NUMBER OF CONDUITS= nn > nn

The number of pipes or conduits in a multiple-pipe or multiple-conduit installation (sections 5.16 and 5.17) has exceeded the number allowed in FEQUTL. The maximum number of pipes allowed is the same as the number of subsections. Thus, the parameter PMXSUB must be increased in the INCLUDE file ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked.

*ERR:529* TOO FEW INTERSECTIONS. FLOODWAY ELEVATION LIKELY BELOW SECTION. IL = nn IR = nn

The defining elevation for the floodway (section 5.12) specified by a given decrement in elevation does not intersect the cross-section boundary. Message may not appear because the condition should be detected in ERR:530.

*ERR:530* DEFINING ELEVATION BELOW CHANNEL BOTTOM.

The defining elevation for the floodway (section 5.12) specified by a given decrement in elevation is below the current channel bottom. Either the cross section is too high or the defining elevation is too low.

*ERR:531* FLDWAY ELEV= ff HIGHER THAN LEFT END ELEV= ff

The defining elevation for the floodway (section 5.12) specified by a given elevation is higher than the left end of the cross section. The cross section must always be defined to an elevation at least as high as the defining elevation.

*ERR:532* FLDWAY ELEV= ff HIGHER THAN RIGHT END ELEV= ff

The defining elevation for the floodway (section 5.12) specified by a given elevation is higher than the right end of the cross section. The cross section must always be defined to an elevation at least as high as the defining elevation.

*ERR:533* INVALID FLOODWAY OPTION IN ABOVE LINE

A floodway option (section 5.12) has been given that is not supported in FEQUTL. Probably an error in entering the option.

*ERR:534* IN LINE ABOVE, USET SELECTED BUT ONE OR BOTH LIMITS MISSING.

In the USET option for the floodway (section 5.12), the user must give both limits and one or both limits are missing from the input.

*ERR:535* NFRAC= nn > MAXPRO=nn. UNABLE TO CONTINUE.

MAXPRO, the maximum number of profiles computed in WSPRO, must be larger than the number of partial free flows to be computed for each downstream elevation. All the profiles for at least one downstream elevation must be completed in WSPROQZ computations (section 5.21). The value of NFRAC is too large for that to be possible. Either NFRAC must be reduced, or a version of WSPRO must be applied with which a larger number of profiles may be computed.

*ERR:536* RECORD ID= aa UNKNOWN.

A record identification (record id) has been found that is not known. This could be an error in the WSPRO input, or a new record id could have been added to WSPRO after WSPROX (section 5.23) was developed.

*ERR:537* STANDARD FLOOD ELEVATION BELOW CHANNEL BOTTOM.

The standard flood elevation given for the conveyance-defined floodway (section 5.12) is computed to be below the current channel bottom. Either the cross section is too high or the standard flood elevation is too low.

*ERR:538* NO INTERVAL FOUND FOR KTAR ON RIGHT

In a conveyance-defined floodway (section 5.12), the target conveyance is computed and a search from left to right is used to find an interval of the cross-section boundary that will contain the value of the reduced conveyance. No such interval could be detected. This indicates that some problem is present in the search method or that something is incorrect for either the shape of or the roughness distribution for the cross section.

*ERR:539* NO INTERVAL FOUND FOR KTAR ON LEFT

In a conveyance-defined floodway (section 5.12), the target conveyance is computed and a search from right to left is used to find an interval of the cross-section boundary that will contain the value of the reduced conveyance. No such interval could be detected. This indicates that some problem is present in the search method or that something is incorrect for either the shape of or the roughness distribution for the cross section.

*ERR:540* TABLE NUMBER= nn NOT FOUND

A referenced table number intended to supply information for the command could not be found. The referenced function table must be input using the command FTABIN (section 5.13) before the current command is encountered in the input.

*ERR:541* X AND Y VALUE COUNT= nn IS ODD. BOTH VALUES MUST BE ON THE SAME INPUT RECORD.

An even number of boundary points on each record of WSPRO input should be detected in WSPROX (section 5.23). The offset and elevation of a point on the boundary of the cross section must both appear on the same input record. A case has been found in which this is not true. This could result from an error in delimiting values on the record.

*ERR:542* SECTION ID= aa HAS NO STATION VALUE.

The given section has no station value in the WSPRO input. A station value must be entered.

*ERR:543* CREST BELOW APPROACH INVALID.

In computation of the flow over embankment-shaped weirs, using the EMBANKQ command (section 5.6), the given crest elevation is determined to be below the bottom of the approach channel.

*ERR:544* WEIR WIDTH MUST BE POSITIVE

In computation of the flow over embankment-shaped weirs, using the EMBANKQ command (section 5.6), the width of the crest is less than or equal to 0. This is invalid. The crest must always have a positive width so that the head relative to the crest can be computed.

*ERR:545* MORE THAN nn OFFSETS FOR EMBANKMENT

The number of offsets for specifying the embankment crest and approach channel exceeds the space allowed. The parameter PMXOFF must be increased in the INCLUDE file ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked.

*ERR:546* INVALID SURFACE OPTION:NEED PAVED OR GRAVEL

The only two surface options valid for EMBANKQ (section 5.6) are PAVED or GRAVEL, and some other option (other than END) has been detected.

*ERR:547* COLUMN ARGUMENTS MUST BE STRICTLY INCREASING

A 2-D table has been detected with column arguments that are not strictly increasing. This indicates an error in the preparation of the table or corruption of the table file.

*ERR:548* MORE THAN nn UPSTREAM HEADS

More than the allowed number of upstream heads has been requested for EMBANKQ (section 5.6). The parameter PMXNHU must be increased in the INCLUDE file ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked.

*ERR:549* MORE THAN nn FRACTIONS OF FREE DROP

More than the allowed number of fractions of free drop has been requested. The parameter PMXFRC must be increased in the INCLUDE file ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked.

*ERR:550* TABLE TYPE= nn UNIMPLEMENTED IN FTABIN. VALID TYPES ARE:nn nn

An unsupported table type has been detected in the FTABIN command (section 5.13). A list of currently supported types is given. The version of FEQUTL must be compatible with the input file processed.

*ERR:551* NO CONTROL FOUND FOR TRANSITION IN FRFTRN.

A control point for the given downstream head could not be found in either of the two cross sections in EXPCON (section 5.7) computations. This error can usually be eliminated by increasing the extension on the upstream cross-section function table to a large value, usually 100 ft or more above its current extent. The EXT option should be utilized if the table is read from a file. If the table is computed in the same input and is stored using the SAVE option (sections 5.8- 5.9- 5.10), one side of the table may be extended by 100 ft or more, making the extension vertical. If this extension is placed in its own subsection, the extension will be simulated as a frictionless wall. If this does not correct the error, friction losses should be added (if none are present), or friction losses should be reduced, if present. It also may be that the expansion losses are too small. Large amounts of velocity-head recovery may result in problems in finding a critical control.

*ERR:552* FOUND AT LEAST nn ITEMS. EXPECTED NO MORE THAN nn

In processing a line of user input, more items have been found than expected. The input for extra input items on a line should be checked. The line where the error was detected is shown as part of the output.

*ERR:553* EXPECTED AN INTEGER NUMBER BUT FOUND aa INSTEAD.

In processing a line of user input, a sequence of characters has been detected instead of an integer number. Some error in the order of input values was detected. For free-format input, skipped values must be indicated by a double comma or by an asterisk (*) place holder.

*ERR:554* EXPECTED A NUMBER BUT FOUND aa INSTEAD.

In processing a line of user input, a sequence of characters has been detected instead of a number (integer or otherwise). Some error in the order of input values was detected. For free-format input, skipped values must be indicated by a double comma or by an asterisk (*) place holder.

*ERR:555* EXPECTED AN IDENTIFIER BUT FOUND aa INSTEAD.

In processing a line of user input, a sequence of characters that is not an identifier has been detected instead of an identifier. The proper spelling of identifier names must be checked. An identifier must begin with an alphabetic character. An error in the order of input values may have been detected. For free-format input, skipped values must be indicated by a double comma or by an asterisk (*) place holder.

*ERR:556* FOUND ONLY nn VALUES ON LINE BUT EXPECTED nn

In processing a line of user input, an insufficient number of values was read. The input line must be checked for omitted values.

*ERR:557* VERTICAL VARIATION OF ROUGHNESS COEF. ALREADY DEFINED IN SUBSECTION NUMBER nn

A duplicate definition of vertical variation of roughness has been given in the subsection in the FEQXEXT command (section 5.9). Vertical variation of roughness must be specified at only the first point of the subsection.

*ERR:558* DIGITIZED INPUT NOT SUPPORTED

A special form of input created by a digitizer is not currently supported in FEQUTL.

*ERR:559* COEFFICIENT OF DISCHARGE <= 0.0 OR > 1.0

A coefficient of discharge input by the user has been detected to be invalid.

*ERR:560* APPROACH SECTION TABLE NUMBER DOES NOT REPRESENT A CROSS SECTION.

The approach-section table given in CRITQ (section 5.4) or GRITTER (section 5.14) is not a cross-section table. Some error is present either in the number given or in the number assigned to the computed cross-section table.

*ERR:561* CONSTRICTED SECTION TABLE NUMBER DOES NOT REPRESENT A CROSS SECTION.

The constricted-section table given in CRITQ (section 5.4) is not a cross-section table. Some error is present in either the number given in CRITQ or in the number assigned to the computed cross-section table.

*ERR:562* SOLUTION DOES NOT EXIST AT DEPTH= ff CONSTRICTED SECTION IS NOT A CONSTRICTION!

In computation of a critical-flow table utilizing CRITQ (section 5.4), supercritical flow has been computed in the approach section. The computations have not been completed at the given depth. It is likely that the cross section given as the constricted cross section is not a constriction relative to the approach cross section at all depths.

*ERR:563* CONSTRICTED FLOW TABLE NUMBER IS INVALID. TYPE MUST BE 2.

The constricted-flow table in GRITTER (section 5.14) is of the wrong type. The wrong table number has been specified, or an error in entering the table type has been made.

*ERR:564* MISSING n-VALUE AT DEPTH NUMBER nn

A value of Manning's n is missing at the nn-th depth number for a subsection. The missing n value must be supplied.

*ERR:565* BOTTOM ELEV. OF APPROACH SECTION ABOVE BOTTOM ELEV. OF CONSTRICTED SECTION.

The bottom of the approach section must not be at a higher elevation than the bottom of the constricted section. Gravity and friction forces are ignored, and as a result any drop in elevation in the downstream direction results in errors.

*ERR:566* INSUFFICIENT SPACE IN ITAB/FTAB TO SAVE TABLE IN CRITQ. NEED nn MORE ELEMENTS.

The critical-flow table is to be saved internally in FEQUTL so that it can be referenced after it is computed just like a table entered utilizing the FTABIN command. Insufficient space has been allocated in the function table-storage system for the critical-flow table. The parameter MRFTAB must be increased in the INCLUDE file ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked.

*ERR:567* aa IS INVALID OPTION FOR VERTICAL VARIATION OF ROUGHNESS.

The following options are supported in FEQXEXT (section 5.9) for vertical variation of roughness: NCON, HYDY, or MAXY.

*ERR:568* ONLY ONE STATION EXISTS FOR FLOW LINE: aa AT STATION ff

In computation of sinuosity of a flow line, only one station has been detected on the flow line named. This is insufficient to define sinuosity. At least two stations must be present on the flow line.

*ERR:569* INSUFFICIENT SPACE IN ITAB/FTAB TO SAVE CROSS SECTION TABLE. NEED nn MORE ELEMENTS

Saving a cross-section table within FEQUTL has been requested but the space in the FTAB/ITAB system is filled to capacity. The parameter MRFTAB must be increased in the INCLUDE file ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked.

*ERR:570* ZERO DEPTH BEFORE NEGATIVE RESIDUAL WHILE SEEKING TYPE 1 LIMIT.

Zero depth in the approach cross section has been computed in the CULVERT command (section 5.5) when trying to find a negative residual in a search for the limiting elevation at section 1 for culvert-flow type 1. This may indicate a problem with the solution process or a large drop in elevation between the approach section and the entrance to the culvert. A large enough drop may invalidate the solution procedure.

*ERR:571* RISE= ff < MIN RISE= ff OR > MAX RISE= ff

The value of rise given for an arch-shaped conduit either is less than the minimum value of rise for a standard pipe or it is greater than the maximum value for a standard pipe. If the measurement is not in error, then the internal tables in MULCON (section 5.16) must be extended or detailed measurements must be taken of the dimensions of the conduit so the shape can be defined and a cross-section table computed.

*ERR:572* SPAN= < MIN SPAN= ff OR > MAX SPAN= ff

Same meaning as ERR:571 except that the span was given as the defining dimension.

*ERR:573* OFFSET SPACE FILLED IN MULCON.

The space for storing offsets has been filled in MULCON (section 5.16) when processing a request for analysis of multiple conduits.

*ERR:574* SPAN <= 0.0 INVALID FOR TYPE=CIRC.

The value of span is utilized as the diameter of the pipe; therefore, the value may not be omitted if the type is CIRC in the MULCON command (section 5.16).

*ERR:575* RISE AND SPAN ARE 0.0. ONE MUST BE > 0.0

Either rise or span must be given in MULCON (section 5.16). A case where neither value was given has been detected.

*ERR:576* TYPE= aa UNKNOWN

The given pipe type is not known in the MULCON command (section 5.16).

*ERR:577* RISE AND SPAN MUST BE > 0.0 FOR TYPE TE

Both the rise and span must be given for true-elliptical pipe in the MULCON command (section 5.16) because no standard dimensions are available to infer one dimension from the other when only rise or span is given.

*ERR:578* APPROACH REACH LENGTH= ff < 0.

The approach-reach length must be positive in the CULVERT command (section 5.5).

*ERR:579* APPROACH LOSS COEF. < 0 OR > 1.

Loss coefficient is only meaningful between 0 and 1 in the CULVERT command (section 5.5).

*ERR:580* Not in use.

*ERR:581* APPROACH EXPANSION COEF. < 0 OR > 1.

Loss coefficient is only meaningful between 0 and 1 in the CULVERT command (section 5.5).

*ERR:582* ROUNDING/BEVELING FACTOR < 1 OR > 1.5.

The factor to account for rounding/beveling of a culvert entrance is outside the range established by Bodhaine (1968) in the CULVERT command (section 5.5).

*ERR:583* DEPARTURE CONTRACTION COEF. < 0 OR > 1.

Loss coefficient is only meaningful between 0 and 1 in the CULVERT command (section 5.5).

*ERR:584* WINGWALL FACTOR < 1 OR > 1.25.

The factor to account for wingwalls is outside the range established by Bodhaine (1968) in the CULVERT command (section 5.5).

*ERR:585* PROJECTION ADJUSTMENT < 0.90 OR > 1.

The factor to account for a projecting entrance is outside the range established by Bodhaine (1968) in the CULVERT command (section 5.5).

*ERR:586* LOSS OPTION: aa INVALID.

The only loss option supported is MOMENTUM in the CULVERT command (section 5.5).

*ERR:587* CULVERT CLASS: aa INVALID.

In the CULVERT command (section 5.5), culvert class must be: BOX, PIPE, MITER, or RCPTG.

*ERR:588* TYPE 46 COEF.: ff < 0.60 OR > 1.

The discharge coefficient is outside the range established in the CULVERT command (section 5.5).

*ERR:589* TABLE TYPE NOT 6 OR 13.

Only table types 6 or 13 can be computed in the CULVERT command (section 5.5).

*ERR:590* TABLE NUMBER: nn IS NOT OF A CLOSED CONDUIT.

The given table number does not represent a closed conduit when a table number for a closed conduit is required in the FEQUTL computations.

*ERR:591* aa IS A BAD CROSS SECTION OPTION.

An unknown option for a cross section has been detected. Valid options are: EXTEND, MONOTONE, NEWBETA, NEWBETAE, NEWBETAM, NOEXTEND, NOOUT, NOSAVE, OLDBETA, OUT1, OUT12, OUT20, OUT21, OUT22, OUT23, OUT24, OUT25, SAVE, SAVE1, SAVE12, SAVE20, SAVE21, SAVE22, SAVE23, SAVE24, and SAVE25.

*ERR:592* TYPE= nn INVALID FOR 2-D FLOW TABLES.

Only types 6, 13, and 14 are valid for 2-D tables.

*ERR:593* WEIR COEF. TABLE NUMBER MUST BE GIVEN.

A weir-coefficient table number for flow over embankment-shaped weirs is not available in FEQUTL storage. It must be input using FTABIN (section 5.13).

*ERR:594* MAXIMUM DEPTH BEFORE POSITIVE RESIDUAL WHILE SEEKING TYPE 1 LIMIT.

The top of the cross-section table has been encountered before finding a positive residual in the search for the limiting elevation at the approach section for culvert-flow type 1. The table must be extended to higher elevations and FEQUTL must be run again.

*ERR:595* TAB#= nn OVERFLOW SEEKING CRIT. DEPTH FOR FLOW= ff TABLE MAXARG= ff

Critical depth could not be computed even though elevations at the top of the table have been reached. Either the flow is in error or the table must be extended.

*ERR:596* TAB#= nn UNDERFLOW SEEKING CRIT. DEPTH FOR FLOW=ff

Critical depth could not be computed in the given table even though elevations at the bottom of the table have been reached. The flow is likely invalid or there is a problem in the solution method.

*ERR:597* INITIAL DEPTH= ff 0 IN SFPSBE.

The initial depth for the computation of a steady-flow profile for subcritical flow is negative, which indicates an undetected input error or a problem with the solution method.

*ERR:598* TAB#= nn OVERFLOW SEEKING SUBCRITICAL SOLUTION. MAXARG= ff

A subcritical solution could not be calculated before elevations at the top of the table were reached. The flow is probably too large for the conduit, or there is a problem with the solution method. The table must be extended and FEQUTL run again.

*ERR:599* INITIAL DEPTH= ff 0 IN SFPSPE.

The initial depth for the computation of a steady-flow profile for supercritical flow is negative, which indicates an undetected input error or a problem with the solution method.

*ERR:600* TYPE= nn INVALID TYPE FOR SUBMERGENCE TABLE.

The table type for a submergence table must be 2, 3, or 4 in the CULVERT (section 5.5) or EMBANKQ (section 5.6) commands.

*ERR:601* TABLE#= nn INVALID SUBMERGENCE VALUES AT TABLE START.

A submergence table in the CULVERT (section 5.5) or EMBANKQ (section 5.6) commands must start with an argument of 0.0 and a function value of 1.0, indicating no reduction in free flow when no submergence is present.

*ERR:602* TABLE#= nn NO SUBMERGENCE IN SUBMERGENCE TABLE.

Submergence effects on the flow were not detected in a table given as a submergence table in the CULVERT (section 5.5) or EMBANKQ (section 5.6) commands. A submergence table must indicate a reduction in flow at some point resulting from the downstream head on the overflow-crest elevation.

*ERR:603* ROADWAY MOMENTUM FLUX FACTOR= ff < 0 OR > 1.

The roadway momentum-flux factor must always be positive but must not exceed 1.0 in the CULVERT command (section 5.5).

*ERR:604* WIDTH FACTOR FOR DEPARTURE REACH 1.0

The width factor for testing the cross section for the beginning of the departure reach must always exceed 1.0 in the CULVERT command (section 5.5).

*ERR:605* BEGINNING ELEV. FOR DEP. RCH.= ff > CLVRT EXIT ELEV. ff

The elevation of the beginning of the departure reach must not be higher than the culvert invert (section 5.5). No abrupt positive step can be present at the exit of the culvert.

*ERR:606* UPSTREAM LINEAR SINUOSITY IMPOSSIBLE FOR FLOW LINE: aa AT STATION: ff NO UPSTREAM STATION EXISTS.

A request for the upstream linear sinuosity in the CHANNEL command (section 5.2) cannot be done at the station because no station is present upstream on the flow line.

*ERR:607* TABLE# 0

A table number must always be positive in the context of the type of table under consideration.

*ERR:608* SUBMERGED ROAD FLOW WITH FREE CULVERT FLOW NOT YET SUPPORTED.

Submerged road flow resulting before the flow through the culvert also is submerged and is not yet supported in FEQUTL.

*ERR:609* ROAD CREST ELEV. HEAD DATUM INVALID.

Probable user error. A road crest below the head datum indicates that water is flowing over the road before water will flow through the culvert. This is not a normal road crossing. If the CULVERT code (section 5.5) is used for a nonroad crossing for which this relation between elevations is true, then the culvert-flow and the flow over the weir crest must be computed in separate tables and then combined with Code 5 Type 6 in FEQ simulation.

*ERR:610* FREE DROP= ff 0 NOT YET SUPPORTED.

A negative free drop indicates velocity head recovery through the culvert system. The approach losses should be increased in the CULVERT command (section 5.5) to force a drop in water-surface elevation. Increasing APPEXP to 1.0 is one option to circumvent this error.

*ERR:611* H/L CRIT RATIO < 0 IN EMBANK.

The critical ratio of head to embankment width applied to distinguish high-head flow from low-head flow is negative in the CULVERT (section 5.5) or EMBANKQ (section 5.6) commands. This is not possible, and the ratio is set to the default of 0.15 for flow over embankment-shaped weirs.

*ERR:612* H/L MAX RATIO < 0 IN EMBANK.

The maximum ratio for head to embankment width applied to issue a warning message is negative in the CULVERT (section 5.5) or EMBANKQ (section 5.6) commands. This is not possible, and the ratio is set to the default of 0.32 for flow over embankment-shaped weirs.

*ERR:613* aa IS AN UNKNOWN UNITS OPTION.

The units option must be either METRIC or ENGLISH and the input must begin in column 9.

*ERR:614* MAXIMUM NUMBER OF SUBSECTIONS= nn EXCEEDED IN REASUB.

In the process of reassigning subsection numbers to avoid noncontiguous applications of the same subsection, more subsection numbers have been added than can be currently stored in FEQUTL. The parameter PMXSUB must be increased in ARSIZE.PRM (appendix 2), and FEQUTL must be recompiled and linked.

*ERR:615* NEWBETA FAILURE. VALUE < 1

Estimates of the kinetic-energy-flux and the momentum-flux correction coefficients are computed in the NEWBETA option. These coefficients should never be less than 1.0, but a value less than 1.0 has been computed.

*ERR:616* RISE AND SPAN MUST BE > 0 FOR TYPE: BOX

Both the rise and span for a box culvert must be given in the MULCON command (section 5.16).

*ERR:617* NO CONTROL FOUND FOR TRANSITION IN FRFTRN WITH RESERVOIR.

A control for a transition could not be found in EXPCON (section 5.7) computations when one end of the transition was a reservoir. Reducing or eliminating the frictional term by giving the length of the transition as zero may solve the problem. However, the error may indicate that the cross-section information is erroneous or that the critical-flow value in the cross section is invalid.

*ERR:618* UPSTREAM SECTION OUT OF ORDER IN EXPCON.

The input line with UP as the location designator does not appear in the expected place in the input for the EXPCON command (section 5.7).

*ERR:619* DOWNSTREAM SECTION OUT OF ORDER IN EXPCON.

The input line with DU as the location designator does not appear in the expected place in the input for the EXPCON command (section 5.7).

*ERR:620* LOSS COEFFICIENT < 0 OR > 1: ff

The loss coefficient for the proportion of the difference in velocity heads is out of the valid range for the EXPCON command (section 5.7).

*ERR:621* U TO D COEFFICIENTS AND TABLE NOT FIRST.

The loss coefficient for flow from the upstream section to the downstream section and the table number used to store the results do not appear in the proper place in the input for the EXPCON command (section 5.7).

*ERR:622* D TO U COEFFICIENTS AND TABLE NOT SECOND.

The loss coefficient for flow from the downstream section to the upstream section and the table number used to store the results do not appear in the proper place in the input for the EXPCON command (section 5.7).

*ERR:623* EXPCON REQUIRES AT LEAST ONE CROSS SECTION. NONE WERE FOUND.

No cross sections were detected in the input for the EXPCON command (section 5.7).

*ERR:624* DOWNSTREAM HEADS NON-INCREASING AT: ff

The downstream heads in EXPCON (section 5.7) must be increasing. A decrease has been found.

*ERR:625* TAB#= nn OVERFLOW SEEKING NORM. DEPTH FOR FLOW= ff TABLE MAXARG= ff

Normal depth cannot be calculated for the given flow. The cross-section table maximum argument has been exceeded. If the flow is unreasonable, some other error may be present in the input. If the flow is reasonable, a problem may be present with the cross-section table, or a problem may be present in the solution method.

*ERR:626* TAB#= nn UNDERFLOW SEEKING NORM. DEPTH FOR FLOW= ff

Normal depth cannot be calculated for the given flow. The depth has become zero in the process. If the flow is zero, some other input error may be the cause, or an error is present in the solution method.

*ERR:627* SLOPE OF CHANNEL IS STEEP.

The slope of the channel is steep for this flow level. Either the channel should be made rougher or the slope should be reduced so that the flow will remain subcritical. CHANRAT (section 5.3) is valid only when the flow is subcritical at all flow levels in the channel.

*ERR:628* CHANNEL LENGTH 0.0. MUST BE > 0.0.

The channel length must be positive in CHANRAT (section 5.3) to be valid.

*ERR:629* ERRKND= nn INVALID. RANGE 0 THROUGH 3.

An invalid range for the error kind for integration in CHANRAT (section 5.3) has been detected. This error should not appear unless the user is trying to override the default value.

*ERR:630* UPSTREAM HEADS NON-INCREASING AT: ff

A nonincreasing sequence of upstream heads has been detected. They must be strictly increasing.

*ERR:631* NO SOLUTION IN SFPSBE. YC= ff Q= ff

A solution for the steady-flow profile in a culvert cannot be calculated. The critical depth and the flow are given in the error message. This error can result for many reasons. It may indicate a problem in the solution pattern for culverts.

*ERR:632* AT ELEVATION= ff SUBSECTION AREA 0 IN SUBSECTION NUMBER= nn CHECK FOR INPUT ERROR OR SWITCH TO NAVM= 1.

A subsection of a cross section with a negative area has been found in the input. This indicates that there is an input error resulting in a large overhang in the channel wall or that an overhang is present. If a large overhang is present, then the method of applying a wetted-perimeter weighted-average value of roughness will have to be used.

*ERR:633* ONLY ONE POINT REMAINS ON THE CROSS SECTION. AUTOMATIC EXTENSION REQUIRED TO COMPUTE.

Only one valid point is present in the cross section. This could result if a table is developed to represent the subsection of the stream for CHANRAT (section 5.3) at a culvert or overflow dam. Extension of the low end of the cross section may be done if the boundary at the low side of the section can be treated as frictionless. Otherwise, one or more points should be added to the section description to extend the low side to match the elevation of the high side.

*ERR:634* Not in use.

*ERR:635* Not in use.

*ERR:636* Not in use.

*ERR:637* LINES OUT OF ORDER. LAST LINE READ:

A particular line type was expected in the HEC2X command (section 5.15), but it was not read. For example, if the number of points for the GR lines is incorrect on the X1 line of the HEC-2 (U.S. Army Corps of Engineers, 1990a) input, this error will be issued if there are not enough GR lines present. This also can result with X4 and NH lines.

*ERR:638* GR LINES FOUND BUT NC OR NH LINE MISSING.

X1 and GR lines have been read in HEC2X (section 5.15) but values of n are unknown. Thus, an NC or NH line is missing in the HEC-2 (U.S. Army Corps of Engineers, 1990a) input.

*ERR:639* X1 REFERS TO PREVIOUS GR DATA BUT NO GR DATA ARE IN HAND.

An X1 line has indicated that the previous GR lines should be used for the ground points, but the previous GR lines have not been read in HEC2X (section 5.15). Lines may be out of order in the HEC-2 (U.S. Army Corps of Engineers, 1990a) input.

*ERR:640* NUMNH= nn > 20 ON NH LINE.

Limit for the number of n values on an NH line in the HEC-2 (U.S. Army Corps of Engineers, 1990a) input used in the HEC2X command (section 5.15) has been exceeded.

*ERR:641* NELT= nn > 20 ON X4 LINE.

The limit for the number of added ground points on the X4 line in the HEC-2 (U.S. Army Corps of Engineers, 1990a) input used in the HEC2X command (section 5.15) has been exceeded.

*ERR:642* NH LINE DOES NOT COVER CROSS SECTION.

The last station on the NH line in the HEC-2 (U.S. Army Corps of Engineers, 1990a) input is less than the last station for the current definition of the ground points for the cross section. Thus, the specification of the horizontal variation of Manning's n stops before the end of the cross section is reached.

*ERR:643* MANNING n= ff 0 IN SUBSECTION nn

A value less than or equal to zero for Manning's n has been detected in the given subsection in the HEC-2 (U.S. Army Corps of Engineers, 1990a) input. Probable error in the format of the input so that the value is set to zero in the HEC2X command (section 5.15).

*ERR:644* TABLE IS NOT FOR CLOSED CONDUIT. NO CHANGES MADE.

A cross-section table that does not appear to be a closed conduit has been detected in QCLIMIT (section 5.18) computations. Therefore, no changes to the critical flow have been made.

*ERR:645* CROSS-SECTION TABLE FOR QCLIMIT MUST BE TYPE=22 OR 25 BUT TYPE= nn FOUND.

The cross-section table must be of type 22 or 25 in QCLIMIT (section 5.18) computations, but another type has been detected. Probable error in the cross-section table number.

*ERR:646* aa IS INVALID MODE FOR HEC2X COMMAND.

An invalid string for the mode has been read in the HEC2X command (section 5.15). Valid modes are: INDIRECT, DIRECT, CHANNEL, indirect, direct, or channel.

*ERR:647* MANNING'S n = 0 IN SUBSECTION nn VALUE SET TO 1.0. PLEASE CORRECT AND RECOMPUTE.

A zero value for Manning's n has been read in the input to FEQX or FEQXLST (sections 5.8 and 5.10, respectively). A value has been given so that computations can continue, but the conveyance results will be incorrect. The missing value should be supplied and the table should be recomputed.

*ERR:648* NO UPSTREAM HEADS GIVEN

No upstream heads have been given for the EMBANKQ command (section 5.6). An ascending series of upstream heads must be supplied and the command must be tried again.

*ERR:649* DOWNSTREAM LINEAR SINUOSITY IMPOSSIBLE FOR FLOW LINE: aa AT STATION: ff NO DOWNSTREAM STATION EXISTS.

The sinuosity cannot be computed in the CHANNEL command (section 5.2) using the downstream-linear option because no downstream station is present.

*ERR:650* PARABOLIC SINUOSITY IMPOSSIBLE FOR FLOW LINE: aa AT STATION: ff. THREE CONSECUTIVE STATIONS NEEDED.

Three consecutive stations are needed on a flow line for the parabolic sinuosity options to be applied in the CHANNEL command (section 5.2).

*ERR:651* TOO MANY ENTRIES IN LSATAB. NUMBER= nn

The number of flow lines has exceeded the space provided. The parameter PMXNFL in the INCLUDE file ARSIZE.PRM

*ERR:652* CROSS SECTION SPACE FULL IN INSPNT. NEED nn POINTS BUT ONLY nn AVAILABLE.

The space for the boundary points on a cross section has been filled to capacity during insertion of offsets for flow lines. The parameter PMXPNT must be increased in the INCLUDE file ARSIZE.PRM (appendix 2) and FEQUTL must be recompiled and linked.

*ERR:653* PWC SINUOSITY OFFSET= ff NOT IN THE OFFSETS FOR THIS CROSS SECTION.

The offset for the boundary of the part of the cross section to which a value of PWC sinuosity applies must be one of the offsets in the sequence of boundary points. An offset has been read in the CHANNEL command (section 5.2) that does not match any point on the boundary of the cross section.

*ERR:654* NO VALUES FOUND ON INPUT LINE.

An input line with a label has no other values. At least one value must be given.

*ERR:655* NO HEADING VALUES AVAILABLE. LINES OUT OF ORDER.

The flow-line names have not been defined, yet information for the lines has been given. A heading line is missing. The order of the input lines must be checked.

*ERR:656* NUMBER OF SECTIONS > nn. INCREASE PMXSEC AND RECOMPILE.

Too many cross sections given in a sinuosity-definition table. The parameter PMXSEC must be increased in the INCLUDE file ARSIZE.PRM (appendix 2) and FEQUTL must be recompiled and linked.

*ERR:657* LENG SPECIFIED BUT NO INITIAL STATION FOUND. SPECIFY AN INITIAL STATION BEFORE THE FIRST LENG LINE.

A LENG line has been read in the CHANNEL command (section 5.2), but the initial station is not known. A station line defining the initial value of stationing for each of the flow lines must be supplied.

*ERR:658* INITIAL STATION MISSING FOR LENG FIELD CONTAINING: ff.

The LENG field in the CHANNEL command (section 5.2) has a missing initial station value. An initial value must be supplied for that flow line.

*ERR:659* STATION MISSING FOR OFFSET: ff

The station is missing for the given offset in the CHANNEL command (section 5.2). The missing station must be supplied.

*ERR:660* NUMBER OF SINUOSITIES: nn DOES NOT MATCH NUMBER OF STATIONS: nn INPUT OUT OF ORDER?

The number of sinuosities given or implied by sinuosity options on a SINU line in the CHANNEL command (section 5.2) must match the current number of flow lines.

*ERR:661* BLANK HEADING IN FIELD NO.:nn INVALID.

A blank heading value has been found. A heading must always be given explicitly. There are no defaults.

*ERR:662* STATION MISSING FOR SINUOSITY= ff

A sinuosity has been given, but no station has been given in the CHANNEL command (section 5.2). Input might be out of order. The station or length line must be ahead of the other lines for a cross section in the sinuosity-definition table.

*ERR:663* NUMBER OF OFFSETS= nn INCOMPATIBLE WITH NUMBER OF FLOW LINES= nn

The number of offsets must match the number of flow lines or be one less than the number of flow lines in the CHANNEL command (section 5.2).

*ERR:664* LABEL FOR 1-D AXIS NOT FOUND. MUST BE AXIS, axis, OR Axis.

The flow-line label for the longitudinal axis was not detected in the CHANNEL command (section 5.2). One of the three options shown must be used.

*ERR:665* LENG VALUE NUMBER nn IS UNDEFINED.

The value nn on the LENG line in the CHANNEL command (section 5.2) is undefined. A default value may have been used in error, or an earlier error has resulted in this error.

*ERR:666* STAT VALUE NUMBER nn IS UNDEFINED.

The nn-th value on the STAT line in the CHANNEL command (section 5.2) is undefined. A default value may have been used in error, or an earlier error has resulted in this error.

*ERR:667* OFFS VALUE NUMBER nn IS UNDEFINED.

The nn-th value on the OFFS line in the CHANNEL command (section 5.2) is undefined. A default value may have been used in error, or an earlier error has resulted in this error.

*ERR:668* SINUOSITY DEFINITION: aa UNKNOWN. ASSUMING CUBIC.

A sinuosity-definition identifier is unknown. A cubic spline is applied in CHANNEL (section 5.2) computations as a default.

*ERR:669* SINUOSITY OPTION: aa UNKNOWN. ASSUMING LINEAR.

A sinuosity-definition identifier is unknown. A linear fit is applied in CHANNEL (section 5.2) computations as a default.

*ERR:670* THERE ARE: nn VALUES ON THE LINE BUT ONLY nn HEADING VALUES

A line of input in the sinuosity-definition table in the CHANNEL command (section 5.2) has a number of items differing from the number of headings.

*ERR:671* INVALID NAME FOR AN INPUT LINE: aa. VALID NAMES ARE: STAT, LENG, OFFS, SINU, HEAD, AND END.

The input line names also may be in all lowercase in the CHANNEL command (section 5.2).

*ERR:672* CHANGE IN SINUOSITY VARIATION INVALID. CHECK NUMBER OF OFFSETS OR STATIONS.

The sinuosity variation must be either PWL or PWC and cannot change along a flow line in the sinuosity-definition table in the CHANNEL command (section 5.2).

*ERR:673* NUMBER OF FLOW LINES= nn TOO SMALL. MUST BE AT LEAST TWO FLOW LINES.

Two flow lines is the minimum number required to define the correction coefficients for channel curvilinearity in the CHANNEL command (section 5.2).

*ERR:674* CHANGE IN DIRECTION OF STATIONING AT STATION: ff INVALID.

The stationing along the flow lines in a sinuosity-definition table in the CHANNEL command (section 5.2) must always increase or always decrease. A direction change has been read.

*ERR:675* STATION MATCH AT STATION: ff INVALID.

Two consecutive stations match along a flow line in the CHANNEL command (section 5.2). This is invalid. All stations on a flow line must be distinct.

*ERR:676* INCONSISTENT STATIONING. FLOW LINE STATIONS MUST ALL INCREASE OR MUST ALL DECREASE.

This error may result from a combination of earlier errors in the CHANNEL command (section 5.2).

*ERR:677* OFFSET= ff PREVIOUS OFFSET= ff

Offsets on an OFFS line in the CHANNEL command (section 5.2) must always increase.

*ERR:678* CROSS-SECTION STATION= ff NOT FOUND.

The given station value could not be detected in the sinuosity-definition table. The CHANNEL (section 5.2) input must be checked for a missing cross section in the sinuosity-definition table or for an extra cross section following the sinuosity-definition table.

*ERR:679* INVALID CROSS SECTION COMMAND: aa IN THE CHANNEL COMMAND.

Valid cross section commands in the CHANNEL command (section 5.2) are: FEQX, FEQXLST, FEQXEXT, and ENDCHAN.

*ERR:680* CHANNEL COMMAND ENDED IMPROPERLY. FINISH ENCOUNTERED BEFORE ENDCHAN.

ENDCHAN should always be used to end the input for the CHANNEL command (section 5.2).

*ERR:681* SPACE OF nn POINTS IN SETMUD TOO SMALL.

The space available for adding the points defining a mud line has been filled to capacity. The parameter PMXPNT must be increased in the INCLUDE file in ARSIZE.PRM (appendix 2) and FEQUTL must be recompiled and linked.

*ERR:682* CROSS SECTION TYPE= nn NOT SUPPORTED IN GRITTER. USE TYPES: 20, 21, 23, or 24.

Not all cross-section types are valid in the GRITTER command (section 5.14).

*ERR:683* FLOW AT SECTION 1 HAS FROUDE NUMBER= ff SEEKING TYPE 1 FLOW LIMIT.

A flow limit for culvert-flow type 1 has been computed in the CULVERT command (section 5.5), but at this limit the Froude number at the approach section is greater than 1. This means that the type 1 limit is invalid. If this results for the lower limit for culvert-flow type 1, the computations continue because the flow at low heads is likely type 0. However, if this results at the upper limit for culvert-flow type 1, then the approach cross section must be changed. Type 0 flow is designed to represent lower flows, not the high flows at the upper limit for culvert-flow type 1. It may be necessary to place an explicit expansion, computed with the EXPCON command (section 5.7), upstream from the culvert. The approach section used for the culvert computations would then be larger than the culvert barrel so that a reasonable limit for culvert-flow type 1 would result.

*ERR:684* NEGATIVE DEPTH AT SECTION 1 FOR TYPE 1 FLOW WHEN HEAD RATIO LIMIT THERE= ff AND THE CULVERT VERTICAL DIAMETER= ff

The input value of the maximum ratio of head on the culvert inlet to the maximum vertical culvert dimension at the inlet has been used as a first estimate of the water-surface elevation at the approach cross section in the process of finding the limit of culvert-flow type 1 in the CULVERT (section 5.5) computations. The elevation computed on the basis of this ratio produces a negative depth at the approach section. This negative elevation is most likely caused by an error in the invert elevation at the approach section resulting in a large drop, larger than the maximum vertical dimension of the culvert, between the invert elevation of the culvert at the inlet and the invert elevation of the approach section.

*ERR:685* CULVERT SOFFIT REACHED IN TY1BDY SEEKING A NEGATIVE RESIDUAL.

Subroutine TY1BDY is applied in the CULVERT command (section 5.5) to compute limits for culvert-flow type 1. In the course of these computations, the depth in the culvert inlet has reached the soffit before a negative residual was found. The computations fail because culvert-flow type 1 should not touch the soffit of the culvert. This message may mean that an error has been made in the specification of the culvert.

*ERR:686* CULVERT INVERT REACHED IN TY1BDY SEEKING A POSITIVE RESIDUAL.

Same as ERR:685 except that the depth in the culvert has reached the culvert invert.

*ERR:687* UPPER LIMIT FOR TYPE 1 FLOW DOES NOT EXIST. TYPE 0 FLOW FOUND. CULVERT REPRESENTATION MUST BE CHANGED. SEE ERROR MESSAGE SUMMARY.

Supercritical flow has been computed at the approach section (section 1) in the determination of the upper limit for culvert-flow type 1. This means that the flow is probably type 0 and not type 1. However, type 0 flow for high heads is not supported in the CULVERT command (section 5.5). Type 0 flow should be present only at smaller heads when it is likely that the area of the flow in the approaching stream could be smaller than the flow area at the culvert inlet. This means that the flow is expanding and not contracting into the culvert. All published discharge coefficients and theories of culvert-flow assume that the flow is always contracting. Therefore, several assumptions are made in the CULVERT command to represent type 0 flow. An expansion loss as a multiplication factor on the change in velocity head is used to represent the loss. The culvert representation is changed by explicitly including an expansion flow table, computed applying the EXPCON command (section 5.7). The upstream cross section for EXPCON is the approach section at which ERR:687 resulted. The downstream cross section for EXPCON is constructed to be larger in area at all flow levels than the culvert barrel. Therefore, the discharge coefficient for the culvert entrance is valid in this case. In the field, the approach section may be smaller than the culvert opening, but there is always a cross section at some point between the approach section and the culvert inlet that is larger or at least as large as the inlet area. If no cross section meeting these requirements is available, then some part of the culvert barrel is obstructed and an incorrect barrel description results. In FEQ model simulation, the two structures--the expansion and the culvert--would be connected by a short branch, perhaps 1 or 2 ft long. The cross section in this branch is the downstream cross section for the EXPCON command, which is the same as the new approach section for the culvert. The closeness of the expansion and the culvert entrance renders the discharge coefficients for the culvert less valid than if the standard culvert-approach conditions were present.

*ERR:688* TABLE#= nn HAS TYPE= nn BUT TYPE= 22 OR 25 IS REQUIRED.

The cross-section table is of the wrong type and does not contain the needed values. A table of type 22 or 25 must be entered.

*ERR:689* FLOW TYPE 6 LIMIT NOT DEFINED. APPROACH AND/OR DEPARTURE ELEVATION UNREALISTIC.

A limit for culvert-flow type 6 may not be computed in the CULVERT command (section 5.5) if the approach or departure reach has an elevation that is above the inlet or outlet soffit of the culvert.

*ERR:690* ROW ARG.= ff BELOW RANGE IN TABLE#= nn

The argument on the rows of a 2-D table of type 10 is below the minimum value for row arguments in the table. The table must be extended to lower arguments, or the cause of the smaller than expected argument must be determined.

*ERR:691* ROW ARG.= ff ABOVE RANGE IN TABLE#= nn

The argument on the rows of a 2-D table of type 10 is above the maximum value for row arguments in the table. The table must be extended to higher arguments, or the cause of the larger than expected argument must be determined.

*ERR:692* COLUMN ARG.= ff BELOW RANGE IN TABLE#= nn

Same as ERR:690 but for columns instead of rows.

*ERR:693* COLUMN ARG.= ff ABOVE RANGE IN TABLE#= nn

Same as ERR:691 but for columns instead of rows.

*ERR:694* PUT1D NEEDS LIMIT OF nn FOR FUNCTION TABLE STORAGE BUT CURRENT LIMIT IS nn

Internally computed values are stored in a 1-D function table with the PUT1D subroutine. The space remaining for function-table storage is too small. The given limit indicates the minimum required space. The parameter PMXTAB must be increased in the INCLUDE file ARSIZE.PRM (appendix 2) by at least the increase shown in the message, and FEQUTL must then be recompiled and linked.

*ERR:695* DROP FROM SECTION 1 TO SECTION 43= nn INVALID. DROP MUST BE > 0.

The decrease in elevation from the approach section (section 1) to the section just downstream from the exit of the culvert barrel (section 43) is the drop for a culvert. A drop must always be present.

*ERR:696* INITIAL SUBMERGENCE OF ROADWAY FLOW STARTS AT ELEV.= ff BUT CRITICAL-FLOW ELEV.= ff IN CULVERT EXIT. FLOW OVER THE ROAD CANNOT BE COMBINED WITH CULVERT FLOW WHEN CRITICAL FLOW IN THE CULVERT EXIT CAUSES SUBMERGENCE OF FLOW OVER THE ROAD.

The roadway elevation is too low to combine flow over the road with flow through the culvert. To simulate this condition, flow over the road should be suppressed in the CULVERT command (section 5.5) by assigning a large value for the elevation of the roadway crest. The EMBANKQ command (section 5.6) is applied to compute a separate table to represent the flow over the road. The tables computed in CULVERT and EMBANKQ are applied in parallel in FEQ to represent the two different flow paths.

*ERR:697* NEGATIVE SINUOSITY FOUND AT STATION: ff

A negative sinuosity has no meaning. It probably resulted from use of a cubic spline when the flow-line distances vary rapidly or erratically. Careful specification of the end conditions for the cubic spline can sometimes eliminate the problem. However, application of the LINEAR option for defining the slopes in the CHANNEL command (section 5.2) will always eliminate the problem.

*ERR:698* NO SUBCRITICAL SOLUTION IN STEADY-FLOW PROFILE. TRY REDUCING STEP LENGTH

A supercritical flow has been detected in the subroutine SFPSBE, Steady-Flow Profile: SuBcritical using Energy. Computation of the steady-flow profile assuming normal depth was attempted, but normal depth could not be computed. An error may be in some user specification, but this error also could result from an error in the program code.

*ERR:699* NO RESULT AT SECTION 2 FOR FLOW TYPE 0 AFTER 100 TRIES.

A solution at section 2 for culvert-flow type 0 was not obtained in the CULVERT command (section 5.5). Thus, it is assumed that culvert-flow type 0 cannot result.

*ERR:700* BARREL FLOWS FULL WITH TYPE 0 FLOW. CULVERT REPRESENTATION MUST BE CHANGED. TYPE 0 FLOW INVALID AT THIS FLOW LEVEL. SEE ERROR MESSAGE SUMMARY.

See ERR:687 for how the representation must be changed.

*ERR:701* FLOW OVER THE ROAD = ff > CRITICAL FLOW AT SECTION 1 = ff FOR TYPE 0 FLOW. CULVERT REPRESENTATION MUST BE CHANGED. SEE ERROR MESSAGE SUMMARY.

Culvert-flow type 0 is not computed in the CULVERT command (section 5.5) if the flow over the road is greater than the critical flow at section 1. Flow over the road and culvert-flow type 0 are inconsistent in any case, and the combination should not be used. The change to the representation is discussed under ERR:687.

*ERR:702* OFFSET ON CREST NON-INCREASING AT OFFSET= ff

The offsets on an embankment crest for the EMBANKQ command (section 5.6) or in the CULVERT command (section 5.5) must always be increasing. The given offset violated this requirement.

*ERR:703* NUMBER OF UPSTREAM HEADS = nn TOO SMALL TO ADD HIGHHEAD FLOW LIMIT.

The head corresponding to the high-head flow limit cannot be added to the flow table because no space remains in the list of heads. The parameter PMXNHU must be increased in the INCLUDE file ARSIZE.PRM (appendix 2) and FEQUTL must be recompiled and linked.

*ERR:704* NUMBER OF UPSTREAM HEADS = nn TOO SMALL TO ADD HEAD AT ROADWAY CREST.

The head at section 1 corresponding to the minimum elevation of the roadway crest cannot be added to the flow table because no space remains in the list of heads. The parameter PMXNHU must be increased in the INCLUDE file ARSIZE.PRM (appendix 2) and FEQUTL must be recompiled and linked.

*ERR:705* ROUNDING/BEVELING VALUE < 0.0 or > 0.14

The value given for the relative rounding or beveling for the culvert entrance is outside the range supported in the CULVERT command (section 5.5). The range given is that for the tables for type 5 flow. Ranges may be smaller. The range is truncated at the limit of the particular table involved, and a warning message is issued in FEQUTL computations.

*ERR:706* WINGWALL ANGLE < 0.0 OR > 90.0 DEGREES.

A wingwall angle outside the valid range has been encountered in the CULVERT command (section 5.5).

*ERR:707* TYPE 5 SUBMERGENCE RATIO < 0.0 OR > 1.0

The ratio of depth to maximum vertical dimension at the exit that causes culvert-flow type 5 to flow full and become submerged is given the value of 0.75 by default and can be changed by the user. A user-selected value outside this range has been detected in the CULVERT command (section 5.5).

*ERR:708* RATIO OF DEPTH TO VERTICAL DIAMETER 0.5 OR 1.0

The ratio for the limit for culvert-flow type 1 has been given outside the valid range in the CULVERT command
(section 5.5).

*ERR:709* RATIO OF HEAD TO VERTICAL DIAMETER < 1.0 OR 1.5

The maximum head ratio permitted for culvert-flow type 1 or type 2 is given by default as 1.4. This limit may be changed by the user. The user-selected value is outside the valid limit in the CULVERT command (section 5.5).

*ERR:710* AT LEAST ONE SUBMERGENCE TABLE IS UNKNOWN. BOTH MUST BE KNOWN.

One or both of the tables specifying submergence on the roadway are missing. Both tables must be present even though no flow over the roadway is simulated. Flow over the roadway is always assumed to be possible in the CULVERT command (section 5.5) if the head is high enough. Therefore, the tables are required in all cases.

*ERR:711* DROP FROM SECTION 1 TO SECTION 43 < 0.01 NOT YET SUPPORTED.

A drop in water-surface elevation between section 1 and section 43 is required in the CULVERT command (section 5.5). Otherwise, computations cannot continue. The restriction is satisfied in many culverts. Recovery of water-surface elevation from section 1 to section 43 may result for steep culverts under submerged flow conditions with a small approach section. Currently in the CULVERT command, a drop in water-surface elevation must be forced for these culverts by increasing APPEXP, EXPFAC, the barrel roughness, or all three.

*ERR:712* GATE SILL ELEVATION= ff < ELEVATION OF FLOOR OF DEPARTURE REACH= ff

The sill elevation of the underflow gate must be at or above the elevation of the minimum-elevation point of the cross section in the departure reach in the UFGATE command (section 5.20). The bottom elevation in the cross section given in DEPTAB should be compared with the elevation given for SILLELEV.

*ERR:713* GATE OPENING WIDTH= ff 0.0

An invalid gate-opening width has been detected in the UFGATE command (section 5.20). The GATEWIDTH identifier must be followed by a numeric value that is greater than 0.

*ERR:714* APPROACH LOSS CD 0.0 OR > 1.0

The discharge coefficient for approach losses to the underflow gate must be greater than zero and less than one in the UFGATE command (section 5.20). Approach losses to a gate structure commonly are small so that values of 0.95 to 0.99 are realistic. A value of 1.0 is valid because this indicates that no losses in the approach section result or that the contraction coefficient already reflects those losses.

*ERR:715* CONTRACTION COEF.= ff 0.0 OR > 1.0

The contraction coefficient must be greater than zero or less than or equal to one in the UFGATE command
(section 5.20).

*ERR:716* IN UFGATE:FLAG= nn NO SOLUTION aa

This message can appear in 10 different cases in UFGATE (section 5.20) computations. In all cases an error has been detected in applying the method of false position to determine a solution to a nonlinear equation. The flow area in the approach section and in the departure section must always be larger than the flow area in the gate opening. The flow must always contract upon entering the gate opening and must always expand upon leaving the gate opening. Also, other earlier errors should be checked because computations may continue in UFGATE even if errors have already resulted. The previous errors may be the cause of this error. If none of these conditions apply, then the program code may need to be changed. If FLAG= 1, then an interval that contains a root could not be found. Therefore, false position cannot be applied. Linsley, Kraeger Associates of Mountain View, Calif., should be contacted to make program modification. If FLAG= 2, then a root could not be found in 100 attempts using the method of false position. The tolerances for convergence EPSARG or EPSF may be too small in this case. Making the tolerances slightly larger may allow convergence to a root. If changes in the tolerances do not result in convergence to a root, Linsley, Kraeger Associates of Mountain View, Calif., should be contacted to make modifications in the program.

*ERR:717* GATE SILL ELEVATION= ff < ELEVATION OF FLOOR OF APPROACH REACH= ff

The sill elevation for the underflow gate must be at or above the elevation of the approach section. The bottom elevation in the cross-section table given in APPTAB in the UFGATE command (section 5.20) should be compared with the elevation given in SILLELEV.

*ERR:718* LESS THAN TWO GATE OPENINGS GIVEN. UFGATE MUST HAVE AT LEAST TWO OPENINGS.

One or less gate opening has been input to the UFGATE command (section 5.20). At least two gate openings must be present for interpolation to be possible in a table of type 15.

*ERR:719* CROSS SECTION OFFSET NON-INCREASING AT OFFSET= ff

In standard HEC-2 (U.S. Army Corps of Engineers, 1990a) input, the offsets on the boundary for definition of changes in Manning's n in the NH lines must match the offsets on the boundary for definition of the cross-sectional shape in the GR lines. Many HEC-2 data sets have been transformed from other computer models that do not specify agreement in the offsets for defining Manning's n and channel elevation. In the analysis of such a nonstandard HEC-2 data set, the offsets on the boundary of the cross section are not increasing when addition of a point to the boundary is attempted in the HEC2X command (section 5.15) so that the added point will match the offset given on the NH line.

*ERR:720* NO SPACE LEFT IN CROSS-SECTION BOUNDARY WHEN ADDING POINT FOR NH LINE.

A point cannot be added to the cross-section boundary in HEC2X (section 5.15) computations for an offset on the NH line that was not on the boundary specified in the GR line of the HEC-2 (U.S. Army Corps of Engineers, 1990a) input data. This results because space for storing cross-section-boundary points is filled to capacity. The value of the parameter PMXPNT must be increased in the INCLUDE file ARSIZE.PRM (appendix 2) and FEQUTL must be recompiled and linked.

*ERR:721* RELATIVE PROJECTION < 0.

The relative projection for a culvert cannot be less than zero in the CULVERT command (section 5.5).

*ERR:722* ANGLE OF INLET BEVEL < 0 OR > 90 DEGREES.

The angle for the beveling of a culvert entrance is outside the valid range in the CULVERT command (section 5.5).