Lab 1: Preparing Data for Analysis and Spatial Analysis

Lab 3: Geoprocessing Introduction This lab introduces geoprocessing analysis in ArcGIS. You will learn the following skills:

. Calculating statistics . Selecting features with SQL . Dissolving features . Clipping layers . Exporting data . Buffering features . Overlaying data . Calculate attribute values

Instructions Read Chapters 8 & 9 of GIS Concepts and ArcGIS Methods and answer questions in Part I. Continue with the tutorial exercises in Part II. You should copy any data you download from the course website onto your flash drive.

As you read through Chapters 8 & 9, you should follow along in ArcMap and ArcCatalog. You will be expected to use the text as reference for Part II – it will emphasize the application of tools introduced in the text.

Deliverables Answer the following questions. All labs should be typed, well organized, and stapled together. You can turn in a hard or electronic copy of your lab.

PART I: Single-Layer Analysis & Dual-Layer Analysis (pgs 323-368) What is geoprocessing and what feature in ArcGIS allows you to conduct these operations? 1. ArcToolbox has an auto-documentation feature. Why is documentation of your geoprocessing an important step in GIS analysis? 2. When is batch processing useful?

Geoprocessing: An example This lab introduces you to more advanced analysis techniques – in “geo-lingo”, the term used is “geoprocessing”. Below is an example of a series of geoprocessing steps that are implemented to find areas that with potential for pesticide use on permeable soils.

of 15 A geoprocessing flow chart

ArcToolbox ArcToolbox is one of the major ArcGIS modules used for geoprocessing, although it is “embedded” in either ArcMap or ArcCatalog. Each process in ArcToolbox is called a tool or command and can be accessed through a toolset or toolbox. Both can contain tools, toolsets, scripts, and models, but a toolbox cannot contain another toolbox

A screenshot of the ArcToolbox menu, viewed in ArcCatalog

. A user can create their own set of operations by writing a script (VBA or Python) or creating a model (ModelBuilder). Both ways can automate a series of operations that will be done repeatedly.

Some examples of what ArcToolbox allows you to do include:  import data  set projection information  re-project data  build topology for your data  create buffers  overlay two data layers & create a single layer  create models

of 15  export and convert files

Running a Tool in ArcToolbox Open the ArcToolbox window, by clicking on the toolbox icon. Navigate to the specific tool you want to use and Double-click. A window will open and allow you to set the various file inputs and outputs and other options related to the tool. If you select on the 'show help' tab on the bottom right of the window, a brief description of each input will appear in the window.

File Name Conventions You will be creating new datasets in this lab. Be sure to create names and pathways with NO spaces, periods, dashes, etc. The only valid name and pathways are underscores (_), letters and numbers. It is recommended that you get into the habit of using a standard convention for naming your datasets.

Documentation of your analysis When conducting GIS analysis, it is recommended that you create proper documentation of your datasets and analytical steps. One way to document datasets is to edit metadata in ArcCatalog to provide data about your data. Using the metadata toolbar, edit metadata to give a brief explanation of the datasets you create.

New datasets created through geoprocessing analysis carry the ‘history’ in the spatial tab of the metadata. I recommend keeping a document (word or notepad) that tracks the steps you take when conducting any analytical processing on your datasets.

PART II: U.S. Urban & Rural Populations

Problem Statement: In 2007 the world’s population achieved an unprecedented status: half the population now lives in urban areas. We want to figure what percentage of US & individual state populations are in urban areas.

. Download Lab4 data from course website and add all files onto a new .mxd doc.

. Take a few minutes to explore the datasets and get to know what kind of data you have to work with.

US Percentage

. First of all, you will notice that you do not have a dataset of the US as a whole. You will create a new dataset that summarizes all the information from the counties feature class. . Open ArcToolbox and navigate to the Dissolve tool (Data Management Tools>Generalization>Dissolve).

1. What is the function of the dissolve tool?

of 15 . Using the Counties feature class, dissolve all features (not on any specific field). Make sure that you use the Statistics field tool.

2. What fields do you need to summarize in order to answer the question in the problem statement?

. Name the new dataset USpop (in Output) and click OK.

. Add the new dataset to your map.

. Now that you have the population and area info for the whole US, you will need to find out the population of all urban areas. You could use the dissolve tool again similar to the steps you took in creating USpop, but you can also use the Statistics Tool in the attribute table to summarize data in an attribute field (pg 327).

. Open the Attribute table of Urban_dtl and right-click on the population field>Statistics

of 15 3. What percentage of the US population lives in urban areas? 4. What percentage of the US land area is urban? (You will have to add a new field, calculate area, and summarize stats to answer this question – read the next few steps to guide you).

. In order to calculate the answer to #4, you will need to know the area of the urban areas. You can calculate area, but first you want to see what projection the Urban_dtl dataset is in.

5. What is the projection?

. Project your dataset into an equal area projection and call the new dataset Urban_US_xxx, where xxx is an abbreviation for the projection you choose.

6. What projection did you choose?

. Add a new field in the Urban_US_xxx file and calculate area.

. Follow the same steps to calculate the area of the whole US.

. Using the Statistics tool get the sum of all urban areas, and the US area from the previous step, go back and answer #4.

State Percentages

. Using the Counties feature class and the dissolve tool, create a state feature class. This time you will have dissolve on the State_Name field. Remember to use the statistics tool to summarize the necessary information in attribute fields by state.

of 15 . Complete the necessary steps to the Urban_dtl feature class to create a feature class of urban areas by state. Call the file Urban_States.

7. What tool did you use and what parameters did you set?

. Now, to answer the question about each individual state - conduct a Spatial Join (pg 365) to create a new feature class that joins the urban information to the States attribute table.

. Look closely at your data – there is a problem with the spatial join. Turn on your Urban_states and States layers and notice how some urban areas cover multiple states. How was that handled in the join? You can investigate the problem by using the Statistics tool in the original files.

of 15 8. Does the Spatial Join create erroneous data? Explain

. Add new (double) field to the joined dataset, called ‘percent’.

. Right-click on the newly created Percent field and go to Field Calculator. Here you are going to calculate percent of urban population by entering in the formula for: (PopUrban/TotalPop2005)*100 (the actual formula will look slightly different – it will be based on your field names)

. Use the Summary Statistics (pg 329) tool to export as .dbf and turn in.

9. What percentage of each state’s population is urban? (Turn in, in table format)

Oregon Urban Map

. Now you are going to make a map of Oregon urban areas. Open a new .mxd and add the States (from last section) and Urban_dtl shapefiles.

. Zoom into Oregon and using the selection tool, highlight Oregon.

. In the table of contents, right-click on the States data layer>Data>Export Data

of 15 . Export the ‘Selected features’ onto your flash drive. Call the file ‘Oregon’

. Add the new dataset to your map document. . Now, you only want to show the urban areas in Oregon – You are going to use the Clip Tool (pg 360).

. You will find the tool in ArcToolbox>Analysis Tools>Extract>Clip.

. The input is the Urban_dtl shapefile, and Oregon is the Clip Feature.

. Save the output, OregonUrbanAreas, to your flash drive and add to your map document.

of 15 . You want to include Vancouver, WA on your map because of its relationship to the Portland Metro area. Write a definition query (right-click to the urban_dtl shapefile and go to properties>Definition query) on the urban_dtl shapefile to only display the Vancouver, WA urban area.

of 15 . Use the Append Tool (pg 364) to append the Vancouver, WA feature to OregonUrbanAreas.

. ArcToolbox>Data Management Tools>General>Append

. The input is the urban_dtl, and the target is OregonUrbanAreas.

. The append tool changes the OregonUrbanAreas file – it does not create a new file.

of 15 . Use these files to create a presentation quality map of all Urban Areas in Oregon (including Vancouver). Add label for the urban area names, population, and area. Add a title and your name.

1. Print Map (or export as a .jpg and email) and turn in.

PART III: Land-Use Regulations & the Urban Growth Boundary (UGB)

Problem Statement: How many tax lots/properties could be designated as rural reserves outside the UGB within Clackamas County? Metro is in the process of designating rural reserves that have “high value working farms and forests or have important natural features like rivers, wetlands, buttes and floodplains.”

“A rural reserve designation means that your rural land will not be considered for inclusion within the urban growth boundary for the next 40 to 50 years.”

You are going to find properties that meet the following criteria for their initial consideration in this a reserve designation. : . At least a mile from the UGB . Zoned as rural, forest, or agriculture . At least 25 acres . No building on the lot

of 15 Start by opening a new .mxd document and adding the Clackamas (taxlots in Clackamas county) and ugb_fill (the Portland Metro urban growth boundary) feature classes. You can find the Clackamas geodatabase on the PCC server here: T:\STUDENTS\GISdata\266\Lab3 . . To determine what properties are at least a mile from the UGB, you are going to create a 1 mile buffer with the Buffer Tool (pg 337).

. In ArcToolbox go to Analysis Tools>Proximity>Buffer

. Save the output as ugb_OneMile to your flash drive and add the new dataset to your map. We will come back to this dataset later.

. Next, you need to determine what properties meet the criteria for size and designation.

. Open the Clackamas attribute table and look through the different fields to see what type of information is linked to the Clackamas taxlots. You should see the owner and site addresses, land value, building value, occupancy, land use, sale price, and others.

. You will use the landuse, A_T_Acres, and bldgsqft fields to write a query to find the taxlots that are designated as rural (RUR), forest (FOR), or agricultural (AGR); at least 25 acres in size; and have no current building.

of 15 . We are going to use it to temporarily ‘hide’ any taxlots that do not meet our criteria for this analysis, by writing a definition query.

Definition Query – This tool allows you to conduct a search (or query) within your attribute table. It temporarily removes (or hides) unwanted features from a dataset based on a SQL query.

. Go to the Clackamas layer properties and write the query below.

1. How many properties fit these three criteria?

2. Create a presentation quality map that shows all the taxlots that meet this criteria. Be sure to get some base layers for your map to put these taxlots into context. Add a title, your name, scale bar, etc….all necessary map elements.

. Now – the final step is to determine what properties lie outside the UGB 1 mile buffer. You can use the Union tool (361-3) to figure this out.

1. What is the difference between the Union & Intersect Tools?

of 15 2. How can you use the attribute table to determine which taxlots fall outside the buffer?

3. How many potential properties can be considered for inclusion as a rural reserve?

4. What percentage of Clackamas county (use acreage) has ‘rural reserve potential’?

5. Of the potential reserves, what percentage is rural? Forest? Agricultural?

. After you run the Union, look closely at the taxlots that are right on the border or cut by the 1 miles buffer.

6. How (if at all), will those ‘cut’ taxlots affect the results of your calculations?

7. What happens if you change the size requirement to at least 50 acres?

8. Create a presentation quality map that highlights the ‘rural reserve potential’ properties, differentiating between rural, agr, and forests, and has the acreage by land-use designation information (perhaps in table format).

PART IV: Accessibility to North Portland Light Rail Stations

Problem Statement: Tri-Met wants to conduct an analysis that determines how accessible people in North Portland are to the Yellow MAX line stops. They came to you to conduct the initial analysis, which is to determine which taxlots are within a .5 and 1 miles from light rail stops.

They have provided you with 4 shapefiles:  taxlots: taxlots within the 97217 zip code  taxlots97227: taxlots within the 97227 zip code  lrt_stop: All Light Rail stop locations  NoPoParks: Parks within the 97217 & 97227 zip codes

To complete this analysis, you will need to:  eliminate all the parks from both taxlot files  calculate distance from light rail stops to taxlots

To complete this project there will be 3 main tools that you will use: Append, Erase, and Buffer

of 15 Start by opening a new .mxd and saving it as NoPoLightRail.mxd. Add the four shapefiles mentioned above.

 At first glance, it seems that we want to start off by using the Erase tool to eliminate the parks from the taxlots layers. But, since we will have to use a few tools on both the taxlots & taxlots97227 layers, the very first thing we will want to do is Append one file to the other.  In ArcToolbox, go to Data Management Tools>General>Append (pg 364)

1. Explain how the Append tool works. 2. How is the Append tool different from the Merge tool?

 Since taxlots.shp has a more general name, we will use that as our “target” layer and the taxlots97227 as the input data set.

3. How did taxlots.shp change after using the Append Tool?

 Now you can remove the taxlots97227 from your map.  The next step will be to eliminate all parks from your taxlots files. Since Tri-Met is interested how acccesible the Light rail stations are to people and nobody lives in parks (except for the occasional vagrant), we do not need to include this in the analysis.  You will use the Erase tool to complete this task. In ArcToolbox, go to Analysis Tools>Overlay>Erase (pg 360)

4. Explain how the Erase tool works

 In the Erase tool wizard, you will set your input feature as the taxlots, and erase feature as NoPoParks (this way the parks will be erased from the taxlots layer). It will create a new file - name this taxlots_noParks and save to your flash drive.  Now that you have all the taxlots in one file and you have eliminated the parks, it's time to use the multi-ring buffer tool to find which and how many taxlots fall within the .5 & 1 mile radius from the stops.  In ArcCatalog, go to Analysis tools>Proximity>Multi Ring Buffer  Using the Lrt_stops as your input feature, create a .5 & 1 mile buffer around each of them. If you wanted to make processing time faster, you could clip the lrt_stops files to the NoPo area, or select those stops and create a new file – two things you should already know how to do.  Create a map (or multiple maps) that identifies the taxlots that are within .5 & 1 mile from each stop, as well as the land-use type of the taxlots that fall within the buffer. Do not forget to add titles, legends, etc. - presentation quality.

5. How many taxlots are SFR & MFR? 6. Can you think of a way Tri-Met could estimate # of people based on the information provided in the taxlots attributes? Explain. 7. Print Map(s) (or export as a .jpg and email) and turn in.