In this lab, you will practice downloading, manipulating, mapping, and analyzing publicly available hydrology data from a variety of online websites to study the Buffalo-San Jacinto watershed subbasin, which encompasses the greater Houston region. Specifically, you will work with watershed and flowline data from the National Flood Interoperability Experiment (NFIE), stream gauge data from the National Water Information System (NWIS), and soils data from the Soil Survey Geographic Database (SSURGO).

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First, you will need to establish a a project folder, where you will store all of the files associated with this lab assignment. When working in a public computer lab environment, we recommend saving your work on an external USB drive. For the purposes of illustration throughout these lab instructions, the the project folder will  will be located directly on a USB drive, which is mapped as the F: drive, though your USB drive letter may vary. If you wish to nest your your project folder inside  inside other folders within the file organization scheme on your USB drive, ensure ensure that no spaces or special characters are used anywhere along  along the entire file path of your your project folder.

1. Using Windows Explorer, navigate to  to the location where you would like to locate your your project folder (likely the E: or F: drive).
2. Create a  a new folder inside  inside your selected location and and name it  it “HydrologyLab”. Remember not to use any spaces. Note the full file path of your your HydrologyLab folder folder.

Connecting to a project folder

Now that you have created a a project folder for  for this lab, you will need to create a new ArcGIS Pro project in it.

1. On the Desktop, click the  the Start menu and  menu and select ArcGIS >  > ArcGIS Pro.
2. In the ‘ArcGIS Pro’ window, select Map.
   
   
   
   
3. In the ‘Create a New Project’ window, for 'Name', type "HydrologyLab".
4. For 'Location', click the  the Browse button  button to navigate to the the HydrologyLab folder  folder created. Once the HydrologyLab folder is selected, click OK.
5. Uncheck Create a new folder for this project.
6. Click OK.
   
   
   
   

Because you created a new project using the Map template, the project opens with a single map already created; however, it is generically named named Map, so you will give it a more descriptive name to differentiate it from the maps created in future labs.

1. In the Contents pane, click Map once to select it. Then, click directly on the Map text a second time and rename it  it "Lab1".
   
   
   
   

Downloading NFIE data

Your Your project folder and  and geodatabase have  have been created, so you are ready to download your first set of online GIS data. You will start by downloading data from the National Flood Interoperability Experiment (NFIE), which is searchable on the ArcGIS Online platform.

1. In a web browser, go towww.arcgis.com.
2. In the search box in the top right of the website, type “NFIE “NFIE-Geo Regions”.

If no items are returned, it is likely because you are signed in to your Rice account and the content is limited to Rice University content by default.

1. If necessary, in the 'Filters' section on the left sidebar, toggle off Only search in Rice University, at which point the proper layer should appear.
   
   
   
   
2. Click the  the NFIE-Geo Regions web  web map.
   
   
   
   
3. On the right, click to  to Open in Map Viewer.
4. On the map, click to  to select the the Texas-Gulf region region, which encompasses Houston.
5. In the pop-up, click More info.
6. In the Content section, right-click the  the NFIEGeo_12.gdb.zip file and  file and select Download Download.
   
   

1. Navigate to  to the location where the zipped file has been downloaded.
2. Right-click the downloaded  the downloaded NFIEGeo_12.gdb zip file and and select Extract All….
3. In the ‘Extract Compressed (Zipped) Folders' window, click Extract.
4. In the new extracted folder window that opens, right-click the extracted  the extracted NFIEGeo_12.gdb folder and  folder and select and  and Copy.
5. Navigate back  back to your your HydrologyLab folder folder.
6. Paste the  the NFIEGeo_12.gdb folder  folder directly inside your your HydrologyLab folder folder. Do NOT paste them inside the the HydrologyLab.gdb geodatabase geodatabase.
7. Ensure that your  that your HydrologyLab folder  folder appears as shown below.
   
   
   
   
8. Return to  to ArcGIS Pro.

Adding feature data in ArcMap

Unfortunately, any changes you make to files outside of ArcGIS Pro are not automatically reflected inside ArcGIS Pro. Since you just added new files to your your HydrologyLab folder folder, you will need to refresh your your HydrologyLab folder  folder in order for them to appear.

1. In the Catalog pane on the right of the map view, expand Folders, right-click your  your HydrologyLab folder folder, and and select Refresh.
2. Expand the  the HydrologyLab folder  folder > NFIEGeo_12.gdb geodatabase  geodatabase > Geographic feature  feature dataset to preview what feature classes, or layers, it contains.

3. Drag the  the Geographic feature  feature dataset from the Catalog pane into the the Lab1 map  map view.

If you ever close the Catalog pane, you can reopen it by clicking the View tab on the ribbon and then clicking the Catalog Pane button.

The polygons in the the Subwatershed layer  layer represent all of the subwatersheds within the Texas-Gulf Coast Region 12, which you selected when initially downloading the data from the ArcGIS Online website. Now you will examine the attributes of this subwatershed data.

1. In the Table of Contents, right-click the  the Subwatershed layer and  layer and select Attribute Table. Expand the size of the table, if desired.

You will notice three of the columns are labeled labeled HUC_8, HUC_10, and and HUC_12, which correspond to the subbasin, watershed, and subwatershed codes respectively. HUC stands for hydrologic unit code, which is a unique identification number assigned to each hydrologic unit in the United States. Further to the right, you will see additional columns containing the actual names of the HUC-10 watersheds and HUC-12 subwatersheds.

1. Close the  the Subwatershed attribute  attribute table.

Adding an online basemap

First, you would like to identify the subwatersheds within the greater Houston region, but, without any additional reference layers regarding streets or administrative boundaries, this would be very difficult to do. Fortunately, you can utilize various basemaps of the world hosted online by Esri, rather than having to obtain all of the GIS reference layers yourself. Because these basemaps are being hosted online, they cannot be edited and can sometimes be slow to load.

Though the Topographic basemap has already been added to your map by default, it appears in the background , it and is visually obscured by the other data layers.

1. In the Table of Contents, uncheck the  the StreamGage, Flowline, Catchment and  and Waterbody layers layers, leaving only the the Subwatershed layer  layer visible.

The basemap is still not visible beneath the the Subwatersheds layer layer, so you will need to make that layer transparent.

1. In the Table of Contents, click the Subwatershed layer to select it.
2. On the ribbon, click the and select the Subwatershed layer. Click Appearance Tab.
   

1. Under effects, type “60”  “60” to change the transparency of the layer.

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Ultimately, you want to select all of the subwatersheds that lie within the Buffalo-San Jacinto subbasin in which Houston is located, but first you will need to look up the HUC-8 code corresponding to this subbasin.

1. Use the navigation tools to to zoom in to  to the Houston region. On the Tools toolbar, make sure that the Explore tool is is on.
2. In Map Display, click near  near the center of Houston.

In the ‘Identify’ window, notice that the the HUC_8 field  field contains the code 12040104, which corresponds to the Buffalo Bayou-San Jacinto subbasin. The first two digits (12) stand for the region (Texas-Gulf Region). The next two digits (1204) stand for the subregion (Galveston Bay-San Jacinto). The next two digits (120401) stand for the basin (San Jacinto). The last two digits (12040104) stand for the subbasin (Buffalo-San Jacinto). The additional two digits added to create the HUC-10 and HUC-12 codes stand for the watershed and subwatershed, respectively.

1. Close the  the pop-up window.

Performing an attribute query

Now you are ready to perform an attribute query to select all of the subwatersheds within the Buffalo-San Jacinto subbasin (HUC-8 = 12040104).

1. On the Map tab, select Select  Select by Attributes….
   

1. In the Geoprocessing pane, use ‘Layer  ‘Layer Name or Table View’ drop-down menu to to select Subwatershed.
2. Use the ‘Selection Type’ drop-down menu to to select New selection.
3. Click Add Clause.
   
   
   
   

1. Select HUC-8, and and is equal to, in the first two fields.
2. Type "12040104" in the last field.
   Verify that your ‘Select By Attributes’ pane appears as shown on the following page and and click Add.
   
   
   
   
3. Click Run.
4. In the Table of Contents, right-click the  the Subwatershed layer and  layer and select Selection >  > Zoom To Selection.
   
   

Exporting selected features

Now that the Buffalo-San Jacinto subwatersheds have been selected, they can be exported into a separate layer stored in your your HydrologyLab geodatabase geodatabase.

1. In the Table of Contents, right-click the  the Subwatershed layer and  layer and select Data >  > Export Features….

Notice that, by default, the ‘Export Data’ window is set to export only the selected features using the coordinate system of the data source. Also notice that the output feature class defaults to the the HydrologyLab geodatabase geodatabase, because you initially set this as your default geodatabase.

1. For ‘Output feature class:’, rename Subwatershed_CopyFeatures to “SubwatershedsNew”.
2. Ensure your ‘Copy Features’ window appears as shown below and and click Run.
   
   
   
   

Since you’ve exported the particular subwatersheds of interest, you may now remove the master master Subwatersheds layer  layer from your map document.

1. Right-click the  the Subwatershed layer and  layer and select Remove.

Saving ArcGIS projects

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1. On the Quick Access toolbar, click the  the Save button button.
   

At the top of the Table of Contents window, notice that the leftmost List By Drawing Order button is currently selected.

1. At the top of the Table of Contents, click the  the List By Source button button.
   

The Source tab displays the full file path locations of all the data layers referenced in your map document. By default, the map document will store this full file path to all of your data files.

1. At the top of the Table of Contents, click the  the List By Drawing Order button  button to return to the list of data layers.

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Now you would like to highlight the boundary of the entire Buffalo-San Jacinto subbasin, but if you tried to change the outline of the current subwatersheds layer, it would change the outline around all subwatersheds. Instead, you will dissolve all the subwatersheds into a single subbasin feature stored in a new feature class inside your your HydrologyLab geodatabase geodatabase.

1. Next to the Map tab, click the  the Analysis tab and and select Tools.
2. On the search bar, type "Dissolve" and and press Enter. Double-click Dissolve (Data Management Tools).
   
   
   
   
3. In the top right corner of the ‘Dissolve’ window, click question  question mark icon.

Read the ‘Dissolve’ window help and review the sample illustration. Notice that this tool dissolves boundaries based on common values in a particular field. In this case, you will dissolve the subwatersheds based on their common subbasin value, resulting in a file showing only the larger subbasin boundary.

1. For ‘Input Features’, drag in the  in the SubwatershedsNew layer  layer from the Table of Contents or or select the  the SubwatershedsNew option  option from the drop down box.
2. For ‘Output Feature Class’, rename the  the feature class from “SubwatershedsNew_Dissolve” to “Subbasin”.
3. For ‘Dissolve_Field(s)’, select the  the HUC_8 field field, since this is the field containing the common subbasin value you wish to dissolve on.
4. Ensure your ‘Dissolve’ window appears as shown below, and and click Run.
   
   
   
   
5. In the Table of Contents, toggle the new  the new Subbasin layer  layer off and on to get a better idea of the result of the Dissolve tool.
6. In the Table of Contents, right-click the  the Subbasin layer and  layer and select Attribute Table.

Notice that only the dissolve field, in this case the the HUC_8 field field, was preserved. Because multiple subwatersheds were dissolved into a single subbasin, it is not possible to retain all of the attributes of each separate subwatershed.

1. Close the  the attribute table.

In order to see all the layers simultaneously, you will give the subbasin boundary a hollow outline.

1. In the Table of Contents, click the  the rectangle symbol beneath the the Subbasin layer  layer name to to open the  the ‘Symbology’ tab.
2. On the top of the tab, click Properties Properties.
   

1.  For ‘Color:’, use the drop-down menu to to select No Color.
2. For ‘Outline Color:’, used the drop-down menu to to select Black.
3. For ‘Outline Width:’, type “ “2”.
4. Click Apply.

Now you would like to create a new layer based on the watersheds in the Buffalo-San Jacinto subbasin. In order to facilitate symbolization and labeling of the watershed names, you will now dissolve the subwatersheds into their respective watershed boundaries using the HUC-10 code.

1. Repeat steps  steps above, but for ‘Output Feature Class’, rename the  the feature class “Watersheds” and for ‘Dissolve_Field(s)’, check the  the HU_10_NAME field field.

You no longer need the original subwatersheds layer for this section. The rest of the analysis will be done with the new new Watersheds layer layer.

1. In the Table of Contents, uncheck the original  the original SubwatershedsNew layer layer.
2. In the Table of Contents, drag the  the Subbasin layer  layer above the Watersheds layer, so it is fully visible again.

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1. In the Table of Contents, right-click the  the Watersheds layer  layer and select Symbology.
2. Use the drop-down menu to to select Unique values.
3. Use the ‘Value Field’ drop-down menu to to select the  the HU_10_NAME field field.
4. Use the ‘Color Scheme’ drop-down menu to to select the  the color ramp of your choice.
   
   

While you could have also dissolved using the the HU_10 field field, the watershed name is probably more meaningful to you than the HU_10 code.

Notice that the subwatersheds from the previous layer have now been grouped into 8 watersheds within the Buffalo-San Jacinto subbasin.

1. As before, apply 60% transparency to the  to the Watersheds layer layer.
2. Make sure that the the Watersheds layer is  layer is selected in  in Contents and and click Labeling  Labeling under Feature Layer tab on the main tab display.
3. Select HU HU_10_Name in the Field drop-down menu.
4. Click the  the Label icon to turn on the labels.
   
   

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Creating a layout

1. On the main tab, click Insert  Insert > New Layout > ANSI Landscape > Letter.
2. Click Insert  Insert tab and and click Map  Map Frame.
3. Select Select the Lab1 map under Map.
   

1. Select Layout  Layout tab and and click Activate Activate.
2. Right-click Watersheds  Watersheds layer and and click Zoom  Zoom to Layer.
3. Select Layout  Layout tab and and click Close  Close Activation.
   

Using techniques you learned last week, create a suitable map, as described for the map layout to be turned in below. If you would like to orient the page in landscape, open the ‘Page and Print Setup’ window from the File menu. All map elements, such as text, legends, north arrows, and scale bars can be added to the layout from the Insert menu.

1. Select Select Share Tab and and click Export  Export Layout.
   

1. Save your  your map document.

FOR MAP LAYOUT TO BE TURNED IN

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1. In the Table of Contents, check the  the Flowline and  and Catchment layers  layers to make them visible.

Performing a spatial query

Now you would like to select out only the flowlines within the Buffalo-San Jacinto subbasin, but this is not possible with an attribute query, so you will instead use a spatial query.

1. On the Main menu, select Select By Location….
2. For ‘Input Feature Layer’, use the drop-down menu to to select Flowline.
3. For ‘Relationship’, use the drop-down menu to to select "Have their center in".
4. For ‘Selecting Features’, check the  the Subbasin layers layers.

This setting ensures that catchments and flowlines which share the outside border with the subbasin will not also get selected.

1. Ensure your ‘Select by Location’ window appears as shown and and click Run.
   
   

All of the flowlines catchment areas that are within the subbasin are now selected.

1. Export the selected  the selected Flowline features  features into your your HydrologyLab geodatabase and  geodatabase and name the  the new feature class “Flowlines”.
2. Remove the original  the original Flowline layer  layer from the Table of Contents.
3. Repeat step 1-7 using Catchment layer as Input Feature Layer and and name the  the new feature class “Catchments”.
4. Uncheck the  the Catchments layer layer, so it is no longer visible.
5. In the Table of Contents, click the  the line symbol beneath the the Flowlines layer  layer name.
6. In the ‘Symbology’ window under Gallery, select the  the Water (line) symbol.
7. Open the  the Flowlines attribute  attribute table.
8. Right-click the  the LENGTHKM field and  field and select Statistics… Statistics….

Symbolizing features using a single symbol

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From the ‘Statistics of Flowlines’ window on the right of map display, you can see there are 543 flowlines in the Buffalo-San Jacinto basin whose average length is 1.94 km and total length is 1052 km.

1. Calculate statistics on the AreaSqKM  on the AreaSqKM  field in the the Catchments attribute  attribute table.

Based on the statistics you have just seen, calculate the answers to the questions listed for the map layout to be turned in on the following page. In order to add the statistics to your map layout, you will insert a rectangle text element.

1. If necessary, go to the  the Catalog window and click Layouts on top of the map display to get in layout mode.
2. Click the  the Insert tab. Select the  the drop down menu of Text and click Rectangle.
   
   
   
   
3. Drag a  a rectangle on your map layout to insert a rectangle text element.

You can edit the text and customize the rectangle appearance by double-clicking on the rectangle text element.

1. Save your  your map document.

FOR MAP LAYOUT TO BE TURNED IN

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Symbolizing features by quantities using graduated symbols

1. Open the  the Flowlines Symbology  Symbology tab.
2. Use Symbology drop down menu to select to select Graduated symbols.
3. Use the ‘Field’ drop-down menu to to select the  the Q0001C field field, which contains the mean annual flow.
4. Click the  the line next to Template to change the symbology of your flowlines.
   
   
   
   
5. Save your  your map document.

FOR MAP LAYOUT TO BE TURNED IN

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1. In the table of contents, check the  the StreamGages layer  layer which you brought in at the beginning with the the Geographic feature  feature dataset from the the NFIEGeo_12 Geodatabase.
2. On the Main menu, click Select By Location….
3. For ‘Input Feature Layer’, check the StreamGage  the StreamGage layer.
4. For ‘Relationship’, use the drop-down menu to to select within within.
5. For ‘Selecting Features’, use the drop-down menu to to select Subbasin.
6. Ensure your ‘Select by Location’ window appears as shown and and click Run.
   
   

All of the stream gages that are within the subbasin are now selected.

1. Export the selected  the selected StreamGage features  features into your your HydrologyLab geodatabase and  geodatabase and name the  the new feature class “SubbasinStreamGages”.
2. Remove the original  the original StreamGage layer  layer from the Table of Contents.
3. Save your  your project.
4. When you are finished creating your layout, close ArcGIS Pro.
   
   

FOR MAP LAYOUT TO BE TURNED IN

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Downloading SSURGO data

1. In a web browser, go to http://arcgis.com.

This is the ArcGIS website.

1. On the top right search bar, search for SSURGO  SSURGO Downloader.  

1. Scroll down and  down and click the  the result SSURGO Downloader.
   

1. On the right hand side of the page page click View  View Application.
   

1. In the search bar in the top corner, type Houston Houston, TX.
   

1. Click in  in the Buffalo-San Jacinto subbasin to select it and and click the  the Download link.
   

1. Right-click on  on your downloaded downloaded BuffaloSanJacinto_12040104.ppkx file and and select Show  Show in folder. Copy the  the file.
2. Navigate back to your HydrologyLab folder.
3. Paste the BuffaloSanJacinto_12040104.ppkx file directly inside your HydrologyLab folder. Do NOT paste it inside the Hydrologylab.gdb geodatabase.
4. Single Single click the  the file and press Enter.
5. A new ArcGIS Pro window will open. You will complete Part 5 using this window. Do not delete your previous ArcGIS Pro window. 

A map package (.mpk), contains both a map document (.mxd) and all data layers referenced by that map document. The new instance of ArcGIS Pro will open showing the different soil classes within the subbasin.

1. On the Map tab, click the  the Explore button.
2. In the Map Display, click on  on any of the soil classes.

By default, you will see all of the attributes of the top-most layer, which is currently the the Subbregion (Subbasin) layer. In order to see the attributes of the the Map Units (soils) layer:

1. In the ‘Explore’ drop down menu, select Selected  Selected in Contents
2. Click Map  Map Units layer in contents to select it.
3. Again in the Map Display, click on  on any of the soil classes.

Scroll down through the list of fields to see the wide variety of data available for each soil class. You may need to scroll to the right to see the actual values stored in these fields. In particular, you will be utilizing the data stored in the the Available Water Storage 0-100 cm – Weighted Average field field.

Geoprocessing: Clipping features

You will now clip the soil polygons to the extent of the Buffalo-San Jacinto subbasin.

1. On the Map tab, click the  the Analysis tab and and select the  the Tools.
2. On the search bar, type Clip and  Clip and press Enter Enter. Click Clip  Clip (Analysis Tools).
   

Read the ‘Clip’ window help and review the sample illustration. Notice that this tool clips one dataset to the extent, or shape, of another dataset.

1. For ‘Input Features’, use the drop-down menu to to select the  the Map Units layer layer.
2. For ‘Clip Features’, use the drop-down menu to to select the  the Subbasin layer layer.

Notice that the ‘Output Feature Class’ did not default to your your HydrologyLab geodatabase geodatabase, but instead to the default geodatabase that was referenced in the map package you downloaded.

1. Rename Output Feature Class to “Soils” and and click Run Run.

Notice that the resulting resulting Soils layer  layer maintains the soil class boundaries, but limits the extent of the soils layer to the extent of the subbasin boundary. You no longer need the master master Map Units layer  layer and may remove it.

1. In the Table of Contents, right-click the  the Map Units layer and  layer and select Remove Remove.
2. Open the  the Soils Symbology  Symbology pane.
3. Click Graduated  Graduated colors.
4. Use the ‘Field’ drop-down menu to to select the  the Available Water Storage 0-100 cm – Weighted Average field field.

Symbolizing features by quantities using graduated colors

Notice that the density of the polygon outlines obscures the colors of the polygons themselves.

1. Shift select select all symbols. Right click to to select Format  Format Symbols….

There is a bug in the software that sometimes prevents the ‘Properties for All Symbols’ interface from opening. As an alternative, you may shift-select all five symbols and right-click and select Properties for Selected Symbol(s)….

1. Click Properties Properties. Use the ‘Outline Color:’ drop-down menu to to select No  No Color.
2. Click Apply Apply.
3. Symbolize the  the Subbasin layer  layer using the same symbology as you used in the  Lab1 map  map document.

Now you will calculate the water storage capacity of the top 1 m of soil within the Buffalo-San Jacinto subbasin.

1. Open the  the Soils layer  layer attribute table.
2. Calculate statistics for the  for the Available Water Storage 0-100 cm – Weighted Average field field.

Based on the statistics you have just seen, calculate the answers to the questions listed for the map layout to be turned in on the following page. Note that, technically, a true calculation of the average available water storage for the subbasin would require factoring in the area of each soil polygon to calculate a weighted average. In this case, just use the statistical mean as it is listed in the ‘Statistics’ window. Similarly, the total water storage for the subbasin would require multiplying the available water storage by the area of each soil polygon and then summing the results. In this case, you may simply multiply the area of the entire subbasin by the statistical mean as it is listed in the ‘Statistics’ window.

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Exporting map documents

1. To export both your your Lab1Hydrology and  and Lab1Soils map  map documents, open each of them in turn and and click the  the Share menu and and select Export  Export Layout….
2. Navigate to  to your HydrologyLab folder.
3. Use the ‘Save as type:’ drop-down menu to to select PDF PDF.
4. Click Export Export.
5. Print both  both map PDFs to turn in
   
   

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2)      Based on your previous calculation of the area of the subbasin in km², what volume of water (km³) could potentially be stored in the top 1 m of soil in the Buffalo-San Jacinto subbasin if the soil were fully saturated with water?