[tz] America/Creston

Chris Walton Chris.Walton at telus.com
Fri Dec 2 04:01:38 UTC 2011

There are two areas within the Canadian province of British Columbia that do not currently observe daylight saving:
a) The Creston Valley (includes the town of Creston and surrounding area)
b) The eastern half of the Peace River Regional District (includes the cities of Dawson Creek and Fort St. John)

Creston does not have a dedicated zone file; it is assumed that residents of Creston should use "America/Dawson_Creek".
This assumption can be inferred from a comment that is currently embedded in the tz database's northamerica file; the comment reads:
        "Matthews and Vincent (1998) write that Creston is like Dawson Creek.".

Earlier this year I stumbled across a detailed article about the time keeping history of Creston; it was written by Tammy Hardwick who is the manager of the Creston & District Museum.  The article was written in May 2009.
According to the article, Creston has not changed its clocks since June 1918.  i.e. Creston has been stuck on UTC-7 for 93 years.
Dawson Creek, on the other hand, changed its clocks as recently as April 1972 (as is correctly reflected in the current tz database).

The current tz rules state that a separate zone file should be created for regions that differ after 1970.
So... I am proposing the addition of "America/Creston" to the database.

Unfortunately the exact date for the time change in June 1918 remains unknown and will be difficult to ascertain.
I e-mailed Tammy a few months ago to ask if Sunday June 2 was a reasonable guess.  She said it was just as plausible as any other date (in June).  She also said that after writing the article she had discovered another time change in 1916; this is the subject of another article which she wrote in October 2010.

Here is a summary of the three clock change events in Creston's history:
1. 1884 or 1885: adoption of Mountain Standard Time (GMT-7) # Exact date unknown
2. Oct 1916: switch to Pacific Standard Time (GMT-8)  # Exact date in October unknown;  Sunday October 1 is a reasonable guess.
3. June 1918: switch to Pacific Daylight Time (GMT-7)  # Exact date in June unknown; Sunday June 2 is a reasonable guess.

On Oct 27/1918 when daylight saving ended in the rest of Canada, Creston did not change its clocks.
By not changing the clocks, Creston had effectively transitioned itself back to Mountain Standard Time.

During WWII when the Federal Government legislated a mandatory clock change, Creston did not oblige.
Creston was able to claim that it had moved itself back to the Pacific Time Zone and could observe daylight saving (Pacific War Time) without changing the clocks.
After the war, Creston conveniently moved itself back to Mountain Standard Time, again with no change to the clocks.

There is no guarantee that Creston will remain on Mountain Standard Time (UTC-7) forever.  The subject was debated at least once this year by the town Council.

Here is a proposed zone entry for the northamerica file:
# Zone  NAME            GMTOFF  RULES   FORMAT  [UNTIL]
Zone America/Creston    -7:46:04 -      LMT     1884
                        -7:00   -       MST     1916 Oct 1
                        -8:00   -       PST     1918 Jun 2
                        -8:00   1:00    PDT     1918 Oct 27 2:00
                        -7:00   -       MST     1942 Feb  9 2:00
                        -8:00   Canada  P%sT    1945 Sep 30 2:00
                        -7:00   -       MST

Alternatively the dates in Oct 1916 and June 1918 could be omitted since we don't know what they are; this would cause zic to default to Oct 1/1916 and June 1/1918.
# Zone  NAME            GMTOFF  RULES   FORMAT  [UNTIL]
Zone America/Creston    -7:46:04 -      LMT     1884
                        -7:00   -       MST     1916 Oct
                        -8:00   -       PST     1918 Jun
                        -8:00   1:00    PDT     1918 Oct 27 2:00
                        -7:00   -       MST     1942 Feb  9 2:00
                        -8:00   Canada  P%sT    1945 Sep 30 2:00
                        -7:00   -       MST

Note the use of the Canada rule in 1942 results in the use of "PWT(pacific war time)" and "PPT(pacific peace time)".

The zone.tab entry should look like this:
CA      +4906-11631     America/Creston    Mountain Standard Time - Creston, British Columbia

# # # # # # 

And now one last tidbit:

In the first of Tammy's articles she quotes the Friday November 1/1918 edition of the Creston Review.
The quote includes these two statements:
	'Sunday the CPR went back to the old system of time...'
	'... The daylight saving scheme was dropped all over Canada at the same time,'
These statements refer to a transition from daylight time to standard time that occurred nationally on Sunday October 27/1918.  This transition was also documented in the Saturday October 26/1918 edition of the Toronto Star.
The Toronto Star articles reads as follows:
	'BACK TO OLD TIME - Canada Returns to Orthodox Measurement of Time To-morrow Morning.
	Ottawa, Oct. 26.---"Daylight saving" comes to an end Sunday morning, October 27,
	at 2 o'clock, when Canada returns to the orthodox measurement of time.  Either
	the simple ceremony of stopping the clock for an hour or sliding the hands forward
	11 hours should be carried out.  To turn the hands back would be to injure its

My reason for providing these two references to the October 27/1918 transition, is that the tz database currently defines it as being on Thursday October 31 instead of Sunday November 27.  This is an error that presumably needs to be corrected in the rules for "Canada", "Regina", "Vanc", "Winn", and "Edm".


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