Error 173: time series has its data out of sequence

One of the more common errors we encounter in the technical support department for PCSWMM is problems with SWMM5 input time series having its data out of sequence. All of the tabular data in each SWMM5 Time Series object (whether or not it is actually used by the model) needs to move successively forward in time (i.e. each data point must occur at a later date/time than the previous data point). SWMM does a data integrity check when it loads a input file and the error message "Error 173: time series X has its data out of sequence" is produced if this criteria is not met.

I have listed some of the most common causes of this error here (in the hopes of saving you some time one day).

1. A data point at hour 24, and another data point at hour 0 the next day (i.e. a second data point occurring at the same time as the previous data point). For example:

06/11/2009 22:00:00 59.2
06/11/2009 23:00:00 80.6
06/12/2009 24:00:00 2.4
06/12/2009 00:00:00 1.4
06/12/2009 01:00:00 0.6

2. The wrong day assigned to hour 0 (i.e. the previous day). For example:

06/11/2009 23:00:00 80.6
06/11/2009 00:00:00 1.4
06/12/2009 01:00:00 0.6

3. The wrong order for the month and day. SWMM5 expects dates to be in MM/DD/YYYY format.

4. Repeated data (i.e. a chunk of the time series is repeated further down in the table).

5. Simply one or more wayward data points (i.e. a date/time stamp somewhere in the tabular data is simply in the wrong place).

The best tip I can give regarding this issue is that if this error shows up in your status report, there is definitely data out of sequence. So if you can't find it at first, keep looking. If it is "out of sequence", there is a good chance the date/time stamp reported in the error is not located at the position in the time series where you would expect it, so look elsewhere. If you send it to us to find for you, you'll owe us lunch!