2.03.2009

Searching for a Parking Space (Updated!)

Here is yet another one of my Business Integration problems, I am working on solving for the City of Sacramento. We (I should say, our Parking Division) has a unique way of "addressing" the parking spaces in our downtown area.

I have developed a way to "geocode" these to our street centerline with an offset which will then accompany the Parking Space/Meter attribute information and, yes, integrated to our wonderful Infor EAM (Enterprise Asset Management System).

The Data

Our Parking Enforcement group provided a Parking Space inventory in Excel that contained "addresses" of the parking spaces. These "addresses" are not actual addresses, but do look like addresses. The Parking Enforcement division has maintained their data for years with this system and so on the right side of the street, the "parking space ranges" are from 00-32 and on the left from 01-31 on each street segment. Since these ranges don't match the existing exhaustive address ranges in our street centerline file, just geocoding these to our street segments don't really work. Some modification of the exhaustive ranges are needed.

Modifying the Street Centerline File

Since our Parking Division only enforces parking spaces in downtown Sacramento, only the downtown portion of the street centerline file is required to be modified ~4000 segments out of ~20,000 segments.

Ideally, the GIS team in the City encourages departments that want to create spatial data use our existing centerline file, parcel file, and master address file without modification. In this case, an exception is made to perform a 1 time generation of spatial data for parking spaces.

A series of queries and calculations were applied to compute additional exhaustive range attributes specifically for parking spaces. Most of this step was not too bad, but it did take about 2 full days to accomplish, since specific queries needed to be made to certain sides of the block.

Geocoding the Parking Space File

Once the street segment file was completed, a custom geocodeer was created that used the modified centerline file as the street centerline base for geocoding. One of my co-workers had created a custom geocoding style that we use for other address searching functions in other websites we maintain, so I used this in my geocoder routine.

Once the geocoder was set up, I took the parking space file I imported into ArcGIS (I did convert the excel file to a Dbase file so I could use it in ArcGIS) and geocoded it.

The first time I ran this, I did find some street address range issues, that I needed to fix. After running several iterations of the geocoder process, I was able to geocode all but 78 of the 21,400 parking space records. The 78 end up having "space range" values beyon the xx32 mentioned above. I will need to work with our Parking Division to work this out, but it won't be too much of a problem.

The Result

Overall, this process worked well. I am going to have an intern make some minor adjustments to the placement of the parking space information and work on a similar process for "angled" parking v. the "parallel parking" mentioned here.

If GIS was consulted before the inventory process began, we could have saved a lot of time of parking enforcement workers filling out an Excel field form and then having to go through this process of geocoding. If Parking Enforcement had worked with our GIS group and used already established GIS field form methodology from the beginning we would have save about a week's time running this geocoding process.

NC

Traffic Sign Inventory ArcUser Winter 2009 Article

Check out my article on the City of Sacramento's Traffic Sign Inventory Project.

I have received numerous calls and email on the I am doing with the City.

NC

ArcObjects 9.3 Help

A few of my students were asking how to navigate the convoluted course of the ArcObject Model Diagrams. You can check under the latest ArcGIS Web Help

http://resources.esri.com/help/9.3/arcgisdesktop/com/vba_start.htm

Hope you find this useful.
NC