An interesting way to look at a community is to map various measures of the value of its parcels, including a measure called the improvement ratio. Many cities, but not all, tax their parcel owners based on the value of … Continue reading
Last week we released a number of new ArcGIS for State Government Solutions, as well as, updates to existing offerings we previously shipped. Some of the highlights of our new offerings include: Economic Development, Transportation and Health. Economic Development Live, … Continue reading
With the release of ArcGIS 10, Esri provides users with a Land Records solution as a core part of the ArcGIS platform. This solution helps you produce great web maps, implement efficient workflows, and incorporate best practices from the land records industry at large.
The parcel maintenance solution has three key parts. First is the Parcel Editor toolbar, which is included with ArcGIS Desktop at the ArcEditor and ArcInfo license levels. This toolbar contains the tools needed to access and work with parcel data. The second part of the solution is the parcel fabric. This dataset manages the spatial and topological relationships inherent in parcel point, line, and polygon data. The third and final part of the solution is the Tax Parcel Editing map. It supports local government workflows and is a multiscale editing map that organizes the survey framework (Public Land Survey System [PLSS] and control), subdivisions, lots, tax parcels, and encumbrances in a fabric data model that can be used with the Parcel Editor toolbar.
One of the most common problems that can occur when working with vector data is maintaining coincidence.
Maintaining coincidence between adjacent polygon features is important when modeling real word information in a GIS. There are a number of tools in ArcGIS 10 for Desktop that allow users to edit and create features that share boundaries, thus helping to eliminate gaps, slivers, and overlaps.
In the previous blog post, I discussed several of the attribute checks you could use to validate attribute updates made on the source parcel data before loading into the fabric. As a continuation, in this post I’ll discuss how to use the geometry and topology checks included in ArcGIS Data Reviewer.
Several checks exist that can help with examining the geometry of the lines and polygons. The first, Invalid Geometry check, looks for features with empty or null geometries as well as non-simple geometries. This check can be run on both the Parcel_Lines and Parcel_Polygons feature classes.
In preparation for loading your parcel data into the parcel fabric there are a number of criteria you have to meet. A critical step in the process is to match your source data to the Local Government Information Model, with all its domains and specific attributes. In this blog I’d like to highlight some of the automated checks in ArcGIS Data Reviewer that can help you validate your data prior to migrating it into this new schema, as it is better to identify any errors before you move to the fabric.
Here is an interesting blog post from the Parcel Editor team for those of you who are looking to optimize your parcel editing workflows and reduce the amount of time you spend annotating your tax parcel maps.
In the parcel fabric, the parcel name text field is used to store the parcel identification number (PIN). This PIN is sometimes called APN (Assessor Parcel Number) or AIN (Assessor Identification Number) and other conventions. This number is usually kept unique by constructing it from the book, page and a sequential number, as well as similar methods. The field might store “264014001” which stands for Book 264 Page 014 Parcel 001 and can be formatted to show “264-014-001”.
Best practices include the use of label classes to show the full PIN when zoomed in and only the last 3 digits when zoomed out.
- Label expression: to separate the parcel number by dashes you can use a label expression similar to this: Left([Name],3) & “-” & Mid([Name],4,3) & “-” & Right([Name],3)
- MapTips: some users prefer to only label the last 3 digits and use a MapTip to show the parcel number when hovering over the parcel.
- To do so, activate your MapTip in the Layer’s Display Tab.
- To get the MapTip in the example above, use the following expression:
” Book: “& Left([Name],3) & vbNewLine & ” Page: “& Mid([Name],4,3) & vbNewLine & ” APN: ” & Right([Name],3)
Here is the second part of a blog post from the Parcel Editor Team. Another approach to alley vacations in ArcGIS 10.
In a previous post, we talked about how to perform a vacation of an ally or right-of-way parcel using the parcel fabric data model in conjunction with the Local Government Data Model and the Tax Parcel Editing Template from the resource center. For this post we are going to talk about the same process, but without recreating the original lots. As with the previous post, we will be working through an example provided by the City and County of Denver. For this example, the lots currently in the database do not match the legal description (the lots should all be 125 X 25), which is a common occurrence in most databases.
Performing the Vacation without re-creating the original lots
Using the existing lots is the easiest and most straightforward way to go, but not the best-practice. You could think of this as the quick-and-dirty way to get the tax parcels added and move on with your day.
1. Begin by creating a connection line for the gap between the two disconnected groups. Use the tool on the Parcel Editor toolbar. This ensures that a construct from parent process will work, since it requires the group to be connected.
2. Use the parcels on the northernmost part of this group, across the gap (alley). Note the 29’ distance and 87 degree bearing. The distance measurement should be 30’, with a bearing closer to 90 degrees. Since we are going with the current set of lots, though, we will simply hit the Apply button to use these numbers.
3. Select just the Tax Parcels that you need to extend to the center of the ROW (Alley) being vacated, right click and select the Construct from parent option.
4.Select the Segmented Line Tool at the top of the Parcel Details window.
Create a two part segmented line over the top of the connection line that you created. Take note that the lines as inversed are 14.515ft, not 15. This is due to the lots/parcels not being repaired prior to the edit.
Note: Be careful, there are two points very close together 81 & 121 in this data.
5. Same for the southern edge, connecting the midpoints together with another boundary line, to form a centerline running down the middle of the alley/ROW.
6. Next step is to create lines across the construction lines used to re-create the ROW (Alley) and the centerline.
a. Start at point 116 as shown here and then place the cursor in the Bearing field
b. We want to extend the parcel line along the same bearing, so move the
cursor to snap to the tax parcel line that you want to pick up, hold
SHIFT and then click to pick up the bearing (this will populate that
value in Bearing field).
c. Purposely type in something longer than 14.5 (1/2 way point or ROW width)
Use the Planarize command to break the line at the centerline. Select
the overlapping piece in the grid, right click and choose the Delete
Rows option to remove it.
7. Continue this process until all the remaining tax parcels have
been extended to the ROW (Alley) center and then merge the smaller
pieces to you existing tax parcels to get you final output. In this
example, there are no historic ROW parcels created, since they were not
there to begin with.
Content provided by Larry and Chris (Parcel Editing Team)
Here is a great blog post from the Parcel Editor Team. Its an overview of the editing workflow you’d go through to vacate an alley in ArcGIS 10.
Alley Vacation – Part 1
The parcel fabric data model lends itself to many improved workflows for managing your parcels, particularly when it is used in conjunction with the Local Government Data Model and Tax Parcel Editing Template for ArcGIS 10, which you can download from the resource center. Some of these improved workflows are hard to detail in the help, though, so we’re hoping some blogs will help out. One of these workflows comes from the City and County of Denver and centers on how you perform a vacation of an alley or right-of-way parcel. The City and County are using the Local Government Data Model, which provides the ability for managing not only parcels, but also Lots and Subdivisions.
There are a few things to consider before performing an alley vacation or creating any new parcel(s).
1. Does the alley exist in the lot layer?
If the alley exists, the first step before doing any work would be to make sure the original lot (alley) is marked appropriately in the historic layer (marked as Vacation).
2. How accurate are the measurements on the adjacent block edges/lots?
In the data that was used for this example, the lots should be 125 feet by 25 feet, but a look in the parcel description shows the measurements are off for some of the lots.
The best practice in this case is to re-enter the original blocks by cogo-ing the outer boundary of the block from recording, and then using the Parcel Division tool or Construction to recreate the lots. Once completed, these blocks can be joined to the Fabric using control points or even orthophotography. Of course, the tax parcels would also have to either recreated from the lots or re-joined to fit the newly constructed lots.
The first workflow listed below can be used for this task. In a later post, will talk about how to complete this process without recreating the lots.
Recreating Blocks and Lots from Records (original city subs)
1. Mark original lots historic or delete them all together from the Fabric. In this example, I’ve left this step until the end so that I can use the lots as reference to name the new ones
2. COGO entire block boundary from record. For this example, all of the lots are 125 X 25.
a. Create a new Plan, and give it an appropriate name.
b. Create a new construction inside that plan, set the parcel template to “lots”
c. COGO the outer boundary like this:
Please note that the alley was divided two pieces. More on that later. Also note that the original lots are displayed in the background.
d. Delete the 575’ measurement
e. Select the Segmented Line Tool from the top of the Parcel Details window:
To start, make sure you cursor is in the FROM cell of the next available row and click in the grid to replace the NW corner, type “23” to get 23 equal segments or right click.
f. Click the SW corner, and do the same thing for all the other edges.
g. Digitize in the connect lot lines, create a connection line for the center of the Alley.
3. Build and Join. For this example, the parcels are turned off and we joined directly to photography as control. Later on, the data can be re-adjusted to proper control if desired.
a. Then create any join links between the existing Parcels and the new lots…make sure to have points turned on for this!
b. Hit OK, and the data will now look like this:
4. This will make the ROW (Alley) Vacation easier since you now have the centerline of the ROW (Alley) to use to expand the tax parcels.
a. With the Tax Parcels and just the ROW (Alley) in question selected, we can use the Construct From Parent option to do the rest of the line work.
b. We can digitize over the connection lines, creating new lines that extend the current tax parcels. The Planarize command can be used to get rid of any excess. We then build to create polygons and merge the smaller vacation leftovers to the current tax parcels, carrying their attributes over to the newly expanded parcel.
c. Finally, mark ROW (Alley) Vacated (Historic).
Content from Larry and Chris (Parcel Editing Team)
We wanted to take a minute to thank everyone who attended our sessions at the UC last week. The feedback we got was outstanding and we look forward to working with you in the near future.
If you couldn’t make the UC Tech Workshops, we’ll try to get the video for the ArcGIS for Local Government: An Introduction Tech Workshop published on the Resource Center later this summer. In the meantime, the presentation is attached to this blog post for reference.
We’re excited to incorporate what we learned at the conference in to our plans and we’d also like to take this opportunity to share with you our plans for the next 60 days (rest of the summer here in Michigan…).
New Maps and Apps:
We will be adding a series of maps and apps to the ArcGIS for Local Government offering. They include:
Maps and Apps Gallery: A web application that provides citizens a single gallery of maps and apps you’ve published for your organization. It also allows external developers who are leveraging your authoritative data to submit their apps for inclusion in your gallery.
Address Editing Map: An editing map that helps planning, public safety, and land records organizations in local government maintain road centerlines w/ address ranges, site addresses, and related postal addresses.
Service Request for HTML 5: A HTML 5 application that allows citizens to submit non-emergency requests for service from a mobile phone, desktop computer or tablet device.
Community Planning: A web application that allows citizens to propose community master plan design alternatives.
Park Finder: A web application that allows citizens to find a park nearby, or list of parks that Offer recreation activities you’re interested in.
Sign Inspection: A universal iOS application that allows public works and DOT field staff to collect new street signs and conduct inspections on existing signs.
Campus Editing Map: An editing map that helps facility managers maintain interior spaces and exterior assets found on building grounds or a campus.
Campus Basemap: A multi-scale basemap for facility managers that can be used as a backdrop for facility applications and to enhance content found in your local government basemaps.
Campus Room Finder: A web application that allows users to find an office, conference room, or other interior space in a building or among many buildings on a campus.
Easier to Deploy:
In addition to adding a new set of maps and apps, we will be taking several steps to make it easier for you to deploy ArcGIS for Local Government in your organization. In doing so, look for:
Quarterly Releases: A consistent quarterly release schedule that includes new maps and apps, updates to existing maps and apps, and any bug fixes reported by users. Our first quarterly release will be in October 2011.
On-premise Offering: A single ArcGIS for Local Government download that is simple to install and configure. This single download will replace the individual downloads on the Resource Center today. It will also allow you to identify one or more ArcGIS for Local Government modules you’d like to deploy in your organization; and install the individual applications contained within each module.
Online Help: An ArcGIS for Local Government online help system for users and partners deploying the system.
Esri is committed to developing a community of partners who are actively engaged in selling and delivering ArcGIS for Local Government. It is through collaboration with its partner community that Esri best meets the needs of local government customers.
In order to make this collaboration with Partners repeatable and successful, Esri has created the ArcGIS for Local Government Specialty designation within the Esri Partner Network. It is designed for Partners who are focused on the local government marketplace and who want to work more closely with Esri.
Several Esri Partners approached the ArcGIS for Local Government team at the UC and are ready to add their applications to growing ecosystem. We will be working with these partners to ensure the applications can be deployed with the Local Government Information Model and simply by users. We look forward to highlighting the good work these partners are doing in local government.
Thanks again for the tremendous feedback at the UC. We were delighted that many of you took the time to attend the sessions we had. As always, feel free to contact us with any specific feedback or questions you may have.