Hydrography Seminar Series - Session 9 (NHDPlus HR)

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Detailed Description

The USGS Hydrography Seminar Series shares success stories from users, provides information on the National Hydrography Dataset (NHD), Watershed Boundary Dataset (WBD), NHDPlus High Resolution (NHDPlus HR), and other related products, and provides a forum for users to learn more about hydrography-related topics. Seminar 9 is an overview of the NHDPlus HR.


Date Taken:

Length: 00:56:56

Location Taken: Reston, VA, US


For more information, contact nhd@usgs.gov or visit https://nhd.usgs.gov

[00:05] Alan Rea: USGS Hydrography Seminar on NHDPlus High Resolution for May 23rd, 2017. Again I'm Al Rea, a Co-Lead for the NHD [National Hydrography Dataset].

[00:21] Could we have the next slide, please?

[00:25] Today, these are the people who'll be speaking. I just introduced myself.

[00:31] Also speaking will be Ariel Doumbouya who's Acting Senior Hydrography Project Lead at the NGTOC, the National Geospatial Technical Operations Center, also Karen Adkins who's a contractor and very much a part of our team at the USGS, and Tatyana DiMascio who's a NHD point of contact with our team there at the NGTOC.

[01:01] If we could go ahead and move to the next slide. This just gives you an idea of what we'll be talking about today. We'll start with an overview of the NHDPlus High Resolution, which I will give. Then after that, we'll go into the workflow and how the data are produced, data access, the review and QC [Quality Control] effort on the Beta products that we're releasing, something called "Refresh" which we'll explain, and a new attribute called the VisibilityFilter.

[01:41] Also I’ll ask that if you have questions, you send those questions to us through the chat window which is on the upper part of your screen if you have the WebEx home page visible. If you've made it full screen, if you put your cursor at the top of that screen, then there will a menu that will come down and show. You can open the chat window there and send us any questions.

[02:18] We'll leave time at the end of the presentation for answering those questions. You can put those into the chat anytime during the presentation, but we'll answer them at the end.

[02:34] Could we have the next slide, please?

[02:38] I wanted to just start out and just give you brief introduction to the NHDPlus High Resolution. It's basically available. We've just released it in Beta version for the seven hydrologic regions that are shown in dark blue there on that inset map. We are continuing to work on the rest of the conterminous U.S., which we expect to complete sometime in 2018. Then, we will be following that with working to complete the data for Alaska, Hawaii and in the U.S. territories in the following years.

[03:27] What the NHDPlus High Resolution is, is basically a scalable geospatial hydrography framework. It is built from the high resolution NHD, also the Watershed Boundary Dataset, and the 3DEP [3D Elevation Program] elevation data.

[03:49] It really brings modeling down to a very local neighborhood level, but still allows us to nest all of that information into a national context, and its connected national network. It is very similar to the NHDPlus Version 2 if you are very familiar with that, but it just has a lot more detailed input datasets and output datasets.

[04:20] Next slide, please.

[04:24] What I want to do here is talk slightly a little bit about the history of the NHD and to give you an idea of where we are now. There's more history before this, but the NHD as we know it really was first released nationally in 2000 at the 1:100,000 scale.

[04:52] After that, there were two separate efforts that took place and one was known as the NHD High Resolution. That one focused on producing a higher level of detail, larger scale data going into the NHD. That was first focused at the 1:24,000 scale, but it also very quickly evolved in many localities and several states to be even larger scale, higher resolution data to the point where today the NHD High Resolution is quite a hybrid dataset of several different scales.

[05:35] For the conterminous US, it's all at least 1:24,000 scale or larger, and there are several whole states that are at much larger scale than that.

[05:48] At the same time that that was going on, a separate group was working on adding additional functionality to the network, and additional network navigation capabilities, and a set of attributes that we call Value Added Attributes.

[06:07] What we're doing now is we're bringing those two lines back together so that we can go forward as a community using a single hydrographic framework, but this new framework will have the ability to generalize to many different scales.

[06:29] Next slide, please.

[06:30] The NHDPlus, just to give you a little bit of background about it, and these next several slides really apply to both the medium resolution NHDPlus and the High Resolution, which is new, what we're just now building.

[06:53] Conceptually, they're both the same. What we do is we combine the NHD hydrography, the watershed boundaries from the WBD, and the elevation data from 3DEP to create an integrated set of several datasets. The most important one of these datasets is the catchments. A catchment is created for each segment and each NHD flowline, so each segment in the stream network.

[07:22] Next slide, please.

[07:26] Here's a picture of several catchments. You can see there's one catchment for each line segment in the NHD network. There's also a catchment for each coastal line segment as well.

[07:40] These cover the entire continental U.S., so that if you drop a drop of water anywhere on the U.S., you would instantly know where in the stream network that water would flow to, and that is by intersecting with the catchment areas.

[08:02] Catchments really are important because they allow us to track the land areas that drain to the stream network, and that way, we can relate conditions on the landscape and landscape processes to the stream network. This is really the first step in modeling the complete hydrologic system.

[08:22] Next slide, please.

[08:24] Here is a basic comparison of NHDPlus Version 2, the medium resolution dataset that's been around now for about a dozen years, and the new high resolution NHDPlus that we're just creating. Nationally, the number of catchments in the medium resolution is about 2.7 million. We'll be going to about 20 million, or even possibly as many as 30 million in high resolution NHDPlus when that's finally complete.

[09:00] We'll be using a 10 meter resolution elevation model or DEM versus the 30 meter that was used for Version 2. Of course, we use that hybrid scale high resolution NHD which is 1:24,000 scale or better versus the 1:100,000 scale that was used for NHDPlus Medium Resolution.

[09:28] We have updated versions of the WBD, and basically our catchment size will go from about 1.2 square miles to around two tenths of a square mile, approximately, in the high resolution NHDPlus.

[09:46] The size of catchments is obviously going to be quite variable in the high resolution NHDPlus because the high resolution NHD itself has a very differing stream density or density of flowlines in the NHDPlus. As far as flow estimates, we have mean annual and mean monthly for the NHDPlus Medium Resolution, but for High Resolution right now, we're only doing the mean annual. We'll probably be adding the mean monthly later at a later time.

[10:28] Next slide, please.

[10:33] I want to show you just some applications of the NHDPlus using the Medium Resolution just so you can see some of the things it has been used for that might give you ideas about things that could be done with a high resolution NHDPlus.

[10:50] Next slide, please.

[10:52] This is showing the area in the Northeastern US that was done with the SPARROW model, which is a water quality model. It uses flows from the NHDPlus as well as the catchment areas.

[11:08] Next slide.

[11:11] This is just some of the results of SPARROW modeling in the northeast. It shows where phosphorus and nitrogen are coming from on the landscape.

[11:22] Next slide, please.

[11:25] You can also use the SPARROW model to see what type of sources are contributing in different areas. This is showing atmospheric point sources - developed lands in agriculture - by state for the Connecticut River Basin that’s as it is delivered to the Long Island Sound. It's a very useful way of modeling water quality.

[11:54] Next slide, please.

[11:54] These are some results from an application called ICWater which is a desktop application that's used for incident response. When there's a spill, such as the spill that were acid mine drainage from the Gold King Mine which was accidentally spilled into the Animas River in Colorado a year and a half or so ago, this application was used to estimate how quickly the water would move downstream and where.

[12:33] Next slide, please.

[12:36] This is some of the results of that model, the ICWater Model, and it shows the colored segment are the stream segments that would be where the plume would go in the eight days following the spill before it got to Lake Powell down on the Colorado River.

[13:00] Next slide, please.

[13:03] What you're seeing here is a simulation of something called the National Water Model, which is being used now in real time. Actually, this has been run for the whole part of the country that you can see here. It's being used to forecast floods. This is being run at the NCAR, the National Center for Atmospheric Research.

[13:34] It's giving us a very much more detailed forecast for flooding. It's actually improved the spatial detail in flood forecasting by more than 700 times. So, there is extremely great amount more information in the flood forecasting models that they're able to do this way.

[14:00] Could we go to the next slide?

[14:05] There are literally hundreds of other applications that have been built from the NHDPlus Medium Resolution. We are hoping and expecting lots more applications to come from the high resolution NHDPlus.

[14:21] I wanted to add just here a little bit of information about what we are calling the Beta release of the NHDPlus High Resolution. This is really the first iteration. The Beta is the first iteration in what we hope to be a cycle of continuous improvement.

[14:44] We do expect to find some problems. We also hope that the data, as it is, is pretty useful for a lot of purposes.

[14:55] We have really focused our efforts on making the new process for the high resolution NHDPlus automated so that we can come back, fix the errors, and refresh within a really fairly short time period.

[15:14] Our goal is to get a refresh done approximately six months after we release the Beta data for any particular [Hydrologic] Region. We'll continue to do that afterwards as needed based on how much the data itself had been changed and how much it's been updated.

[15:37] In this process, the user community, you folks out there on the landscape, are really critical to this process. We really need for you to download the data, use it, find problems, tell us what you find, and tell us where those problems are so that we can fix that and get it improved.

[16:02] It's only going to improve if people use it and provide us feedback, So, don't wait until someone else fixes it. Please, we really need your help to make the data better.

[16:18] Next slide.

[16:21] Next up, Ariel Doumbouya is going to talk about the workflow and how we produce NHDPlus High Resolution.

[16:29] Ariel Doumbouya: Thank you, Al. This is a very high level overview of what our workflow looks like. This is for the Build/Refresh process. We'll talk more about what that Refresh process means a little bit later today.

[16:42] There are five steps to what we're doing. We're going to focus mostly for my part on these first three.

[16:50] The first thing we do is prep our components, those Ingredient Datasets that Al was talking about  - the NHD, the WBD and the 3DEP data - and then we deliver them to our contractor. From there, that's where we actually build the NHDPlus High Resolution Beta product.

[17:05] They deliver that back to the USGS. From there, we go into our Beta distribution. This is where we’re making the data publicly available and sharing it with all of you, and then we go into QC process where we're engaging outside reviewers to help us improve that product - exactly what Al was just mentioning on his last slide.

[17:27] From there, we are implementing revisions to the NHDPlus High Resolution data. That goes into our component dataset. That may be the NHD needs updated, that may be the WBD.

[17:39] When we're working through this process, we're actually engaging with our stewardship community. It's not necessarily USGS who will implement those changes, but we are working with our partners in determining which edits we would like to incorporate and who will be responsible for those.

[17:54] From there, that's when we'll go into our next stage, which we'll talk about at the end of the presentation or near the end of the presentation, which where we actually rebuild the NHDPlus product using those corrected component datasets to create the NHDPlus Refresh Version 1 and then distribute that publicly as well.

[18:15] What's really important about this process is that we were focused on engaging the medium resolution NHDPlus team, including Horizon Systems who did much of the development work for that medium resolution product. Our goal was to use what we had learned from that process to support the high resolution and elevation hydrography data. For us, it was about modernizing the process to support that high resolution data.

[18:44] This is just one other view of our workflow - very much simplified. But you can see we have our ingredient datasets with the NHD, WBD, and our 1/3 arc second seamless DEMs. That goes into the Build/Refresh process which is the actual software that creates the NHDPlus High Resolution data, and then we deliver that data to all of you as Hydrologic Subregions or HU4s.

[19:07] This graphic or map shows our current availability of data, but it's not just about that focus. One of the focuses of this slide is the data availability, but the second is about user engagement. If you look at the blue areas you see at the map here, this is where NHDPlus High Resolution data is currently available, and we may also have some QC review in work.

[19:37] We currently have approximately 20 percent of conterminous United States HU4s available. We expect to have 40% coverage by the end of the year. In the green areas that you see on the map, this is where we'll be producing NHDPlus High Resolution data at a later date. These areas are currently open for NHD and WBD editing.

[20:01] For those of you that are on the phone, if you're a part of our stewardship community and you have edits that you'd like to incorporate to the source data so that we can have that in the NHDPlus High Resolution product, these are the areas where we would highly encourage you to start performing that work.

[20:16] In the orange or the coral areas, depending on your screen, this is where we're preparing data for NHDPlus creation. We like to limit the editing in these areas, close editing a bit, so that we can prepare the data for delivery to the contractor.

[20:35] Then, in the yellow areas - but really all areas, O.K. - the USGS is actively seeking volunteers for our Beta review and QC. We'll talk more about that later in the presentation.

[20:51] This is another look at that map, but here we have it in a tabular view. This is essentially our current program of work, and it's in approximate priority order. There were a number of considerations when we determined the sequence, but overall, this pretty much represents - starting with some of our easier units first - and consulting with some large projects that would need the NHDPlus High Resolution data.

[21:16] This also gave some of our other  high priority areas time to prepare their source data for the NHDPlus High Resolution process.

[21:24] Again, these items in blue here - same color scheme - are currently available as Beta data, and then the following colors just represent our future plans including some pilots in Alaska and Canada.

[21:36] Just to point out, all of this information is also available on our NHD website at https://nhd.usgs.gov. Feel free to go there and we'll always keep this current. We're always posting updates as things develop and we have more data available.

[21:51] Next, I’ll talk a little about data access. Al’s given an overview of the NHDPlus product overall. I've given you a little bit about the workflow and production, but for those of you who would like to start downloading this data and use it, we'd like to give you some more information there.

[22:11] This is our NHD website, and on the left side, there's a link that says "Get Data Products and Map Services" and then from there you can link to our data products and services.

[22:22] Just as a side note for the services, that’s currently NHD and WBD only, but we will have more coming soon for the NHDPlus High Resolution.

[22:35] When you click on that link, you have two options. Both of these access the exact same data on the exact same server.

[22:44] The first option is to use The National Map Download Viewer. That's the item under the green box. The second option is to download directly from our Amazon cloud server. That's the link in the purple box.

[22:58] Another note here is that for Department of the Interior users, you may find this purple link a little bit faster.

[23:09] When using The National Map Viewer, this is just an online mapping tool for downloading NHDPlus High Resolution, NHD and WBD, in addition to other National Map themes, as shapefiles or geodatabases.

[23:25] NHDPlus High Resolution, we have as file geodatabases, but depending on the product you're looking for, there are additional file formats.

[23:34] We also have a Download Manager. That's very handy and allows a very convenient way to manage downloading multiple datasets so you can load everything into a queue and bulk download as many files as you would prefer.

[23:50] This is just a view of the TNM download viewer. When you open up this site, on the left here, I've selected NHDPlus High Resolution data because that's the product that I'm interested in for today, and then I click on the "Find Products" button.

[24:07] From there, depending on where I've zoomed in and what I have selected, you'll see that I have these two NHDPlus High Resolution data products available, and then in this case, I'm interested in 0108. You'll see there are two download options. We have both the vector data and the raster data available for download. You can choose either or you can choose both depending on your needs.

[24:35] The NHDPlus direct download link also includes both the vector and raster components for whatever hydrologic unit you're interested in, and the vector data as I've mentioned earlier, and again, this is the same data on the same server, there are just two different access points.

[24:53] The vector data is a file geodatabase and that's zipped, and the raster data are 7zip files.

[25:04] What do you get when you download this data and you unzip everything? The vector data includes that file geodatabase. Within that file geodatabase, we have the hydrography feature dataset which have all of our hydrography feature classes.

[25:18] We have our NHDPlus feature dataset which has all of those feature classes, we have all of the WBD feature classes that you're used to seeing, but in addition to that, we also have these Value Added Attributes. Those are included as tables.

[25:33] There's so much here and it's hard to fit in all in the screen. There's also so many attributes here, it's really hard to go over the ones that might be relevant to everyone on the call. For time's sake, I'm just going to highlight a few of my favorites that I find useful in my work, and that I use on a regular basis.

[25:53] The first one that I prefer to use on a fairly frequent basis is the NHDPlus EROM table. What this does, this is our Enhanced Runoff Model. It gives flow estimates from almost every single high resolution NHD flowline feature. If you look at the graphic on the left, this is actually depicting the flowlines symbolized with those flow estimates from that model.

[26:19] The next one that I'd like to use a lot is the NHDPlus Flowline VAA table. This one includes attributes like StreamOrder, StreamLevel, StreamCalc, but we also have things like drainage area square kilometer, and elevation. We have both the raw elevations and the smoothed elevations. Those can be very handy as well.

[26:42] I definitely encourage you guys to download these, dig through them and see which attributes you might find useful for your work.

[26:52] That wraps up the vector data. In addition to that, we have the raster download that I mentioned. This includes a lot of the source data - so what did we produce these rasters from. In addition to things like a shaded relief for you, flow direction grids, flow accumulation rasters.

[27:14] The power of the NHDPlus is really comes from the integration of the vector data that I mentioned, the raster data, and these Value Added Attributes mentioned above.

[27:31] With that, I'd like to switch it over to Karen Adkins and Tatyana DiMascio to talk to you a little bit about the Beta review and the QC process.

[27:44] Karen Adkins: Thank you, Ariel.

[27:54] Thanks, Ariel. This Beta data is ready to use, but we do know the data may contain some defects. So, we're asking the community to help us  improve the data by performing quality control review on the Beta dataset.

[28:10] My name is Karen Adkins and I will be discussing our overall workflow, our high level process for the Beta QC, as well as our current workflow that includes providing Esri Map Packages to help perform the review.

[28:24] Tatyana DiMascio is going to take us into the future with the Mark Up Application. She'll also talk a little bit about how to contact us if you're interested in helping with the review.

[28:34] The NHDPlus High Resolution Beta QC is an important part of our overall process for improving ingredient datasets, in particular the NHD and the WBD. The NGTOC partner support Points of Contact,  the POCs, work with the reviewers to identify issues, either on the ingredient datasets before the NHDPlus process proceeds - that's what we're calling our pre QC which is on the right hand side of your screen - or on the NHDPlus Beta datasets themselves.

[29:14] The POCs then coordinate with production and our partners to ensure that the edits that were made by the reviewers are validated before going into the editing process on the ingredient datasets. That's where we actually correct the datasets to make those improvements.

[29:39] The process that we're currently using - this slide depicts our workflow that we're currently using - we are providing map packages to the reviewers. These map packages contain the NHDPlus datasets, a couple reference datasets as well.

[29:59] It also contains empty feature classes so that the reviewers can add points, lines, and polygons to identify where there are problems in the data, and also indicate how to fix the problem. We're managing that through an ArcGIS Online group.

[30:17] We post the map packages, the reviewer downloads the map packages, then they perform the review according to the user guide that we've developed to help with that review.

[30:27] The yellow bubbles that you see in the middle of the screen identify some areas of review. The one area that is taking the bulk of the effort of the review is the isolated network QC. That's where we’re relying on a lot ofreviewers that have local knowledge of their areas so they can help with resolving some of those isolated networks. That's really big and important part of the QC.

[30:54] Once the review is complete, the reviewer then repackages the data that includes the edits  and any additional ancillary datasets that they bring into the map package when they're reviewing the data and post that back to the online QC group.

[31:09] That's been an effective way for us to manage the review to date. We are changing that. Tatyana is going to tell you about the Markup application.

[31:20] Tatyana DiMascio: Thank you, Karen. This is Tatyana, and as Karen mentioned, we'll take you to the future and hopefully, not too distant future. We are hoping to release a web application called Markup relatively soon. It's in the final stage of testing right now.

[31:38] What this application allows us and the community [to do], it's a web-based, user-friendly tool that would allow somebody in the general public or any NHD/WBD users to go in this web application and provide suggested corrections if they're seeing issues in NHD, WBD, or NHDPlus. We call it the "Suggestions Markup" - that's for our Markup application.

[32:08] Overall, the users will be able to view the layers. They'll be able to view all the other markups that somebody has submitted in a certain area. They'll be able to create markups for existing features, providing suggestions for corrections for existing features.

[32:33] Or they will be able to also create markups for new features if they feel like a new feature should be added somewhere, they could create a markup for a new feature.

[32:38] That goes into the web application into a database. Internally, how do we consume those markups?

[32:44] We have an ArcGIS add-on in ArcMap. This will be provided to our internal NGTOC editors, as well as our trained NHD and WBD partners in the state who would help us to implement those markups into the ingredient datasets.

[33:03] They will be able to submit queries to query the markups with the web application, and they'll be able to change the status for the markups. If they accept the markups, when it's validated, they'll flag it and then they incorporate the change to the ingredient dataset. They will flag it as resolved.

[33:20] If, for some reason, the markup doesn't get validated, it'll get flagged as won’t fix. There will be a comment providing an explanation on why something has been declined. If review is in progress, then the markup will be flagged as in progress. All of that will be reflected back to the web application. The users will be able to go in and see the status of their submitted markups.

[33:44] We're very excited. We're hoping this will improve the process significantly. It will play a key role in our NHDPlus High Resolution QC process.

[33:52] So I know both Al, Ariel, and Karen mentioned getting involved. If somebody is interested in helping with the Beta QC review process or in the future you have any other questions about applications that we're utilizing on the Refresh process, you can contact your NHD and WBD Point of Contact.

[34:20] How do you find that information?

[34:21] On our NHD website, if you to click on "Stewardship" there is a map. This map allows you to access information for your Point of Contacts, your Technical Point of Contacts, your Principal Stewards in the state, and then your USGS National Map Liaison. You'll also be able to read the Stewardship MOU if there is one in place.

[34:43] Any of those Points of Contacts should be able to direct you to the right person. They should be able to answer your questions or help you to get involved.

[34:52] If you click on the map - this is an example of California - you'll see all the contacts are listed in a little pop up box, their phone number, email address, you can contact them directly.

[35:11] Now, we'll talk a little about the Refresh process.

[35:17] You already saw this version of the slide. Right now, we are using ingredient datasets in producing the Beta version for NHDPlus High Resolution. We're giving an opportunity for the community to get involved and provide comments for the Beta version before we go to the Refresh process to create the version 1.

[35:37] This is what our refresh process looks like with the Beta version in place.

[35:42] Once we eliminate the Beta version out of the picture and version 1 comes into the picture, then this is what the refresh process looks like.

[35:56] What would trigger the Refresh process? We have discussed determining some detection change for ingredient datasets. If a lot of edits were done in either NHD, WBD, or 3DEP, then there will be some sort of mechanism in place that would flag this area for refresh process and those are the areas that would get updated from the version, whether it’s version 1 or 2, to the following version.

[36:24] We talked about the Beta QC, the current process, we want to go through QC review process and validation, we make the changes to the ingredient datasets and that kicks off the Refresh process for the version 1.

[36:43] Now, I'll hand it back to Ariel to talk about VisibilityFilter.

[36:46] Ariel Doumbouya: Thank you, Tatyana. Now, this will maybe explain why the drainage area square kilometers is one of my favorite attributes.

[36:56] The VisibilityFilter. The VisibilityFilter is essentially an attribute that we've introduced into the NHD source data that's used for scale representation. This attribute is currently available in the NHD dataset and it's applied to the NHD source data. This is a pre NHDPlus process. It is currently based on an NHD generalization process.

[37:27] What this attribute provides you is filtering of the data. This is not a generalized product. There's no actual removal of features or feature simplification. This is all about filtering the vector features.

[37:43] What we have available for NHDPlus High Resolution is Region 1 and Region 6, we have populated this VisibilityFilter attribute. What that will provide you is a method to filter your vector features at eight approximate scales.

[38:03] What the data has included is a coded value within the VisibilityFilter attribute that will indicate that the feature is appropriate for use at the defined scale and all larger scales. This is currently available for NHDFlowline, NHDWaterbody, NHDArea and NHDLine feature classes.

[38:24] If you look at this table on the right, we've listed some of the scales that we have available. The VisibilityFilter is the actual coded value or the domain that you would enter into that attribute field. We've also provided you with some sample queries that you could use.

[38:43] For example, if you wanted to take a look at the NHDPlus High Resolution product and do a comparison to the Medium Resolution, you could put a display query or you could also use a Select by Attributes query and enter VisibilityFilter greater than or equal to 100,000. That would show you the features that were appropriate for use at that scale and anything larger.

[39:10] As far as current status of this goes, we're currently in an implementation phase. This will become an automated process prior to NHDPlus High Resolution creation. The new process will allow the VisibilityFilter attribute to be populated on the NHD source data, which will then become part of the NHDPlus High Resolution product from those diagrams that we've showed you with that ingredient dataset.

[39:36] Ryan Teter is leading this program with many other across the program. He'll be populating this attributes for that NHD source data in the coming months.

[39:45] Just to give you guys a sneak peak if you haven't downloaded the data yet to see what it looks like, this is  01080203 - an 8-digit hydrologic subbasin. This shows the data with a display query for 24,000 scale. This is showing everything that's appropriate for use at 24,000 and higher.

[40:09] If I switch that scale to 100,000, you can see some features start to be essentially removed, but they're not actually removed. They're just not displayed. Then 250,000, 500,000, 1,000,000, 2,000,000, and 5,000,000.

[40:33] Very quick. Very easy. A very simple way for you to be able to go in and just query that data and select it for whatever scale you may need.

[40:43] There will be future work that will involve generalizing catchments to filter both the catchments and the attributes. Those will match the generalized vectors. But that's more that we will be working on as the NHDPlus program of work continues and we have additional coverage there.

[41:02] Just as a reminder, this is highlighting Region 6 and Region 1. It shows you where we have that VisibilityFilter information available. I strongly encourage you to download these datasets and really any other NHDPlus High Resolution Subregions you're interested in and look and see what it can do for you.

[41:24] Try out this VisibilityFilter attribute, look at some of the other NHDPlus components and see if that is something that can be helpful for you like the EROM values. That's still one of my favorites, but I think the generalization and VisibilityFilter is going to be my new favorite for my work.

[41:44] Lots of things to provide you there with the rasters, the vectors and all of those Value Added Attributes including this new one.

[41:51] With that, I will switch it back over to Al.

[41:57] Alan Rea: OK, thanks a lot, Ariel. We're seeing quite a few questions coming in, both on the chat window and in the Q&A window. I gave you the wrong information initially and said “Chat”. Either one will work if you can find either of those in the controls for the WebEx.

[42:18] Go ahead and put your questions in there. We're seeing quite a few questions come in. We'll get to those here in just a moment.

[42:26] I just want to reiterate, if you're interested in helping us with the Beta review and QC, if you already know your Regional POC for hydrography, you can go ahead and contact them directly or just email  NHD@usgs.gov and we'll get it forwarded to the correct people.

[42:51] Let us know in that email what areas in particular you're interested in doing the review on.

[42:59] Also, we'll have the recording for this seminar as well as all the previous hydrography seminars in our Seminar Series on the website that's indicated there with the link.

[43:12] There's always lots of information being posted to the NHDPlus High Resolution website, which has the link right there. Lots of information that's going on there, almost daily changing right now. Lots going on, so keep your eye on that web page.

[43:33] Lastly, you can always contact me if you have questions or want to talk to me directly. That's my contact information there.

[43:40] Now, Becci Anderson and Sue Buto are helping to manage all of the questions that have been coming in.

[43:49] Becci, you're going to ask the first question?

[43:57] Becci Anderson: Yeah, we have a question about documentation. What documentation is available for the NHDPlus High Resolution and where can it be found?

[44:07] Alan Rea: OK, I'll take that question. We decided to roll out the data before we had everything done. This is a Beta product after all. We're trying to provide access to the data soon as we can. We have a user manual that is in development right now. It'll be posted on the webpage, hopefully, pretty soon.

[44:32] Initially, we're going to put up just the data dictionary portion of the user guide, which is the most critical part. We hope we can get that up in the next few days. The rest of the user guide is going to take a little bit longer for us to get through the process. We'll have more documentation there soon.

[44:52] You can always look at the Version 2 NHDPlus User Guide if you're confused about concepts. Because again, the concepts are very, very similar, just some of the data formats and a few of the field names and so forth are different in the High Resolution.

[45:10] Next question?

[45:11] Sue Buto: How about this one? Will you incorporate the 3DEP lidar elevation data in future refreshes?

[45:21] Alan Rea: I'll take that question as well. The 3DEP lidar data is continually being added to that 1/3 arc-second or 10 meter resolution seamless national dataset. That's what we use for the NHDPlus High Resolution.

[45:45] It's resampled, so if it's one meter resolution lidar data, it gets resampled to 10 meters. That's what we're using at least for now for high resolution NHDPlus. At some point in the future, we'll probably change that to use the full resolution.

[46:05] We wanted to at least get through the country once over, probably a couple times over using the 10 meter resolution for now, but it does get represented in that data by resampling.

[46:22] So, next question?

[46:24] Becci Anderson: Yeah, this is Becci again. Will this data be available in a relational data format such as Postgres?

[46:33] Alan Rea: We are exploring the types of non-proprietary dataset formats that are out there right now. We have a project going on right now that's investigating that. Just so that you know, the data comes in a file geodatabase which is an Esri format, but you can load it into a PostGIS, you can load it in QGIS. It goes in pretty easily into both of those open source packages.

[47:09] We'll try and get a link somewhere on the web page to point you to some information about specifics on how you do that. The file geodatabase format that we're currently releasing is usable in those open source packages.

[47:28] We do plan to continue that research and offer some other formats in the future.

[47:36] Sue Buto: Next question. How will you coordinate edits between volunteers using the Markup Tool and edits made by NHD stewards?

[47:51] Alan Rea: Basically, that Markup Tool. The tool that is...I forgot the name of it. If we could go back the slides (#40) to Tatyana's slides that shows the web Markup Tool.

[48:10] There's another tool that the stewards will see all of the edits or all of the markups - it's called the “Desktop Application” there.

[48:22] Stewards, anyone who does a checkout of NHD data or WBD will see any of the markups that anybody has put in through the web application. Is that right?

[48:38] Ariel Doumbouya: Yes. Al, this was designed to be a companion to either NHD update or WBD, whatever types of edits you want to be doing. Essentially, the editors will be doing their work like normal, whether they're internal or external.

[48:52] There's a button that you can press that says "Show me Markups." That's essentially what it will do and show you your markups in your areas. You can choose to complete those markups while you're doing your regular edits, and then just status them properly, please.

[49:11] Or you can choose to disregard them and we'll be coordinating those through our other processes with our Stewardship Points of Contact and by reaching out to the stewards in those areas. They go hand in hand - they're companions.

[49:27] Does that answer everything?

[49:29] Alan Rea: Yeah, I think that does.

[49:33] Becci Anderson: All right, another question. Do you expect the QC review will result in changes to NHD and WBD or only to the specific NHDPlus products?

[49:42] Alan Rea: Let's see. There are some changes that we expect that would be made to the specific NHDPlus products, such as the BurnLineEvent and Sinks. But, for the most part, we expect most of the edits are going to be done to the actual NHD or WBD dataset.

[50:07] Ariel, do you want to add anything to that?

[50:17] Ariel Doumbouya: Yeah, that is correct, Al. We anticipate that most updates will occur to the Ingredient Datasets.

[50:27] Sue Buto: What criteria are used to define the Visibility scales?

[50:33] Ariel Doumbouya: We actually did not have enough time, unfortunately, to cover that in detail today. I would highly recommend if you would like to learn more about generalization and the Visibility factor that you visit our NHD website.

[50:46] We have a page there that is dedicated to the VisibilityFilter information. We have referenced some work by Larry Stanislawski and others who have lead their research over the last few years on implementing this process and designing the rules and the criteria.

[51:03] We will be providing additional information coming up soon. We'll have some dedicated webinars happening and some presentations specifically on the VisibilityFilter, the business rules, the logic, how it's applied, how it's updated, how it's maintained, etc. More coming very soon there.

[51:25] For now, NHD website, I think “/VisibilityFilter” or something similar to that [https://nhd.usgs.gov/VisibilityFilter.html].

[51:34] Sue Buto: How does the incorporation of LiDAR derived DEM, and synthetic stream network geometry play into NHDPlus HR?

[51:41] Alan Rea: What we're planning to do is  - we're working toward a point where we will be getting our hydrography derived directly from lidar DEMs, but that process right now is not completely laid out, I would say. There are still some research questions to be done there.

[52:16] If we happen to have lidar derived hydrography that has been carefully quality controlled and put into the NHD, then if the elevation data is also coming from the lidar, it will work pretty well as our current process stands.

[52:40] Ultimately, what we hope to do is make that process faster, getting hydrography derived from the lidar DEMs, but if we have that kind of data right now, it will work quite well with the current process.

[52:58] Next question?

[53:00] Sue Buto: Will the data be available as a web service and kept up to date with that service or via that service?

[53:06] Alan Rea: Do you want to take that one, Ariel?

[53:12] Ariel Doumbouya: Yes, I can. We're currently developing NHDPlus High Resolution web services. We have a couple things that we've implemented so far. We don't have any basemap caches yet.

[53:27] We have a dynamic WMS service that we're currently using for the Markup application. Because of what Tatyana mentioned earlier, we're in the final stages of wrapping that up and getting that deployed.

[53:40] We're still in development on that, but we will be making Web services available to the public for NHDPlus High Resolution in the coming months.

[53:54] Becci Anderson: Do we have time, for maybe, just one more, Al, do you think?

[53:58] Alan Rea: Sure.

[53:59] Becci Anderson: All right. What are the major differences between the NHD 24K and the NHDPlus HR data aside from the Value Added Attribute table?

[54:09] Alan Rea: I'll take that. The major difference is that we have catchments and we have raster data, as well. We have the flow direction, flow accumulation grids.

[54:23] Then I guess the other difference is in the vintage. The NHD High Resolution is a continuously updated product, whereas, the NHDPlus High Resolution is based on snapshots.

[54:40] We take a snapshot of the NHD High Resolution, the WBD, and the 3DEP data and we embed that into the NHDPlus High Resolution, that is a static snapshot from that point on for that version of the High Resolution NHDPlus. Whereas, all of those other datasets, all of those three ingredient datasets, continue to evolve on an almost daily basis. That's another one of the major differences.

[55:13] Sue Buto: Do we have a second for one quick last one that will kind of move us into what's next?

[55:18] Alan Rea: Sure.

[55:19] Sue Buto: Two related questions. Devoting webinars to demonstrating Value Added Attributes and/or seminars that go into greater detail while again on Value Added Attributes. Less on workflow and development coordination, but more about using the dataset and the utility of the dataset.

[55:40] Alan Rea: I think that's great feedback. We'll definitely try to do that here sometime in the fairly near future. We're going to do a basically repeat of this seminar since a lot of people were not able to attend today because we actually filled up our phone line. We'll plan on doing that and then we'll try to provide another seminar in the near future after that and talk more about applications and how to use the data.

[56:17] All right, I think with that, we are going to conclude today's seminar. Thank you all for joining us. If you have any more questions or feedback, please send us an email.

[56:34] Again, NHD@usgs.gov is probably the best way to contact us, or you can contact me directly if you have feedback you'd like to give to me directly.

[56:46] Thanks again and we'll see you next time.