Figuring out dive site Zone Codes?

Hi all,

Maybe I'm just incompetent, but I can't seem to figure out Zone Codes.

When I happen to know the name of a site, it's no problem: just use the map to look up the name & cross-reference the number. But if I don't know the name of the site, I can't seem to figure it out. There's no series of clickable maps beyond the main zones, is there?

FYI, I'm looking for names/codes for Vieques in the Spanish Virgin Islands [TWA]. The listed names are utterly inscrutable to me & don't correspond to the dive guides I've seen.



Figuring out dive site Zone Codes?


From the "Geographic Zone Codes" web page you select the zone ("TWA" for example).  When the next page appears, click on the Region name on the displayed map ("Region 6 -Greater Antilles & Virgin Islands" for example).  On the next map that appears, select the two-digit code area of interest ("Puerto Rico 63" for example).  You're then given one more map where you can select the four-digit code area ("Vieques Island 6305" for example).  When you click that name, you then have a tabular listing of all sites in that four-digit zone code.  I presume you’d done that already.


The final table lists ONLY those sites where a REEF survey has already been conducted.  The site name is usually what was on the submitted REEF survey.  Often the survey was conducted at a recreational dive site.  In that case it's given the name that dive operators use for that site.  However, different people may call the site different names so it can be confusing.  If possible, the REEF survey should have coordinates for the site so that subsequent surveys are assigned the correct eight-digit code - if there is any doubt as to dive site location.


Often when the site name seems cryptic ("Vieques VC1" for example), it's because the REEF survey was done in conjunction with a related scientific research effort.  That research effort would assign site names based on whatever system works best for that research program.  Therefore you get what seems like random letters/numbers.   The research sites may or may not be associated with recreational dive sites.  Only by matching coordinates would REEF/you know. 


REEF usually doesn't give out its site coordinates.  There are a few reasons for that.  For example, some dive operators and researchers provide site coordinates to REEF only if those coordinates remain confidential.   Another reason might be that REEF would not want certain sites to be targeted by fish collectors or fishing operations.  The bottom line is that you personally can’t use coordinates to locate sites on the REEF database.  Instead all you can do is look on the REEF database to see if you recognize the site name.  If the name isn't listed, check with the dive operator to see if the site might have other names it might go by.   If you still don't get a match, then tell REEF you are submitting a new site name.  If you can provide coordinates for that new site, then REEF can crosscheck your site coordinates to those it already has.  If there isn't a match, then a new eight-digit GIS code will be added to the database based on your survey.  If your site coordinates match a site already listed, then your dive survey site will be given that matching eight-digit code.


Sorry this was such a long explanation, but I wasn't sure how far along you got to finding site names (GIS Codes).  If you find a match between your dive site and the dive site name listed in the REEF database, then you're set.  If you don't find it on the database, then you'll probably be the first to make a survey at that dive site.


I hope the above helps.




If I misspoke, or if someone else has more insight to Zone Codes, PLEASE chime in…


AAT Member (TWA) - REEF Member Since 1998

Aha. Gotcha.

Thanks for the explanation. For some reason it hadn't occurred to me that the sites were intentionally being shielded.

I'll just use Google Earth to locate a GPS coordinate & submit that, I guess. That's a bit problematic because I generally freedive in warm water. Without scuba's limitations of time & exertion I often end up surveying in large areas or over multiple sites, i.e. all the way around a cay or bay, from in-shore to rather off-shore, knee-deep to 40', sand to turtle grass to reef.

Seems more natural & accurate to report a map location than a coordinate, but I suppose it doesn't really matter all that much.

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