Including support for Army Corp WL data

[saeed-moghimi-noaa]

@gseroka @allenea @carolakaiser @SorooshMani-NOAA

All

Here I am adding some communication between @allenea @carolakaiser and others on how to access Army Corps WL data and its relative vertical datum.

It would be great if we continue this discussion here to have good documentation up until we find a brave volunteer to implement the support in Searvey.

Please tag other here as well,
Thanks
-Saeed

Update
I revised the quoted email formatting style to be easier read:

FYI... I followed up with the US Army Corp (for southern region location) and the only way to know those offsets is by looking at the [dated] website. It looks like most gages are going to be in NGVD29 and the numbers seem to line up with the VDatum offset to NAVD88. However, that likely doesn't apply for all gages from what I've been told. So it may take some reverse engineering to determine what the offset to get to NAVD88 is and from there you could use VDatum to figure out which datum correction gives you that offset value. Or we'll have to manually collect those offsets and store them somewhere that they can be referenced.

Eric

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Thank you. That's what we'll do. I just wanted to make sure there was no better streamlined approach for determining that information.

Best,

Eric

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If memory serves correct NGVD29 is predominant. You can navigate to the gage on the site and it should tell you what datum is used.

lb

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Hi Lysanias,

This is very informative. Thank you for providing such a quick reply.

I am noticing one key piece of information missing. This piece about the "Adjustment for vertical datum NAVD88 (2009.55): -0.96 ft." is important because I don't see in any of these options the vertical datum which the gage collects data in isn't explicitly stated. Maybe all gages are NGVD29?

https://rivergages.mvr.usace.army.mil/WaterControl/stationinfo2.cfm?sid=01300

If that is the case, can you confirm or provide documentation that supports that assumption? I used VDatum and it shows the offset to be -0.961. So not exact but pretty close.

Is this information in the API/web service anywhere or is there documentation that provides this information?

V/r,

Eric

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Eric,
RiverGages

The only parameter that may need to change is the site id unless you are pulling time series data. GetVariableInfo, GetSites, and GetSiteInfo only rely on the “site”parameter while GetValues, and GetFValues require the additional parameters to be set to pull the correct data. All parameters require a value for all methods even if they are not used by the method because of how ColdFusion components operate when invoked.

The first link is an example of how to query for site information. The other methods query for meta-data and observations:

https://rivergages.mvr.usace.army.mil/watercontrol/webservices/rest/webserviceWaterML.cfc?method=RGWML&meth=getSites&site=rcki2&location=rcki2&variable=HP&beginDate=2019-03-25T00:00&endDate=2019-03-26T23:59&authtoken=RiverGages&authToken=RiverGages

Below are all the "Meth"-ods for the RiverGages WaterML webservice. All the URL parameters are always required for any call; follow the above example as a template.

• GetValues
• GetVariableInfo
• GetSites
• GetSiteInfo
• GetFValues (same as GetFalues except it only returns observed/measured values versus forecast values)

lb

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Eric,

We have a web service that provides temporal and meta-data. I will send you the details.

lb

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Hi,

I was wondering if you had an API or some sort of way for us to easily look up things like lat/lon, gage elevation, gage datum, offset to NAVD88 to other offsets that you have collected and provided via the website. Do we have to manually go through the website and record these offsets?

We have learned about this method for retrieving data, however, we aren't sure what datum this data is in or what offsets we need to make to correctly adjust the water level datum.

https://rivergages.mvr.usace.army.mil/watercontrol/webservices/rest/webserviceWaterML.cfc?method=RGWML&meth=getValues&location=01300&site=01300&variable=HG&beginDate=2020-04-05T00:00&endDate=2020-04-10T23:59&authToken=RiverGages

Can you please advise?

Eric

[SorooshMani-NOAA]

@abdu558 please look at this ticket. This is another one of the sources that we'd like to add. We'll talk about development tomorrow in the meeting. Looking forward to seeing you there!