How can I use GIS: Cities

Anytime you have data that has geography (place) associated with it, GIS is the tool of choice. Before discussing your GIS system, let's look at a few examples.

Municipality Examples

• convert street data to M – shape "true-length" data or geo-database in local projection with fields such as:

  surface type – Chip seal, asphalt, concrete, road mix/gravel;
  Pasar Rating – 1 to 10 condition rating scale
  condition – good, fair, poor;
  reason for condition status – potholes, cracks, other;
  base type –Concrete, BAM, road mix, unknown;
  last maintained – date field, etc.

with this data set populated correctly you could query for the last date the road was chip sealed and determine if any pre-– application work such as filling potholes is necessary. You can predict future maintenance needs and make presentations to the public as well. (see LLC_/examples/ "Street Maintenance")

• populate a login – secure, online webpage that on-call field crews could use to bring up the location of the curb stop at anytime of the day or night so as to quickly stop a water or gas leak. (Secured) (see "Client Login" for example)
• publish a map-based mosquito spraying web announcement that is available to the general public. (Unsecured)

 

Needs assessment
What you need depends on what you have and what you want to do. If you're brand-new to GIS, don't worry we have almost 20 years of combined experience with this technology. The first step is to perform an honest assessment of your current capabilities. The next step is to envision what you want to do. Often this is incredibly difficult since this technology is new and rapidly changing. For example, if you didn't know cell phones existed you wouldn't know to ask for one. The best way to determine what your needs are is to look at past problems and if they involve "space" then they probably can be addressed by GIS. In the cell phone example remember coming home to your wife without a gallon of milk and her stating, "I sure wished I could've gotten the message to you". Have you been at a meeting where you are discussing some feature of the land, like the current road conditions for a subdivision, and wished you could pull up a map depicting just how well you've been maintaining those roads to satisfy angry taxpayers.

The first step in determining what you need is to consider the following factors:

1. Flexibility – the first factor to consider is map and data flexibility. Flexibility in this instance is defined to be the ability of the map and associated data to be limited, analyzed, amended, or new data synthesized. A printed paper map has no flexibility, i.e. – what appears is all there is unless it's edited by pencil or pen. At the opposite end of the scale is an online map depicting production records compared for three of seven wells on a multi-bore well site. It is even possible for records, either the geometry or the attributes or both, to be edited in the field then subsequently uploaded back to the server so as to update the published map document at a distance in real time. Remember that is flexibility increases so does the cost and complexity of the system. As such is extremely important to determine what level of flexibility is needed because that directly impacts the three factors mentioned next.
2. Location – just where will GIS data be created, maintained, and disseminated from. Will that data only be available in house or through secured Internet access?
3. Device – what types of devices will be able to access this data? Will it only be available for PC? Will users in the field desire access via their phone? Will you have field crews using data loggers that will be adding or amending data off-site?
4. Users – what types of users will be operating the GIS system? Will it be available to a group of employees with very basic capabilities that could use Arc Reader or Google earth and KML? Will you be performing complex operations that require GIS analysts either in-house or under contract? Will field technicians be entering GIS data either in-house or via cell phone or Internet connection?

Solutions
There are limitless combinations of systems but here we consider the three most common scenarios. Although it is possible to operate an in-house GIS department using spreadsheets and a superlight client like Google earth, it is not advisable nor are open source software solutions desired because of lack of support. Cheap often equates to reduced functionality and increased complexity.

Scenario one: in-house processing/light client
In-house GIS department for recording and analyzing municipal data such as streets, water and gas lines, zoning, etc. Master maps created and used by the GIS department are then published in a reduced – function format for viewing by other departments by freeware such as Arc Explorer. Simple data can be converted to KML and used in Google Earth for viewing by other departments. Limited point data can be published to the Internet using Google API interface for free but publishing line and polygon data and making it secure costs about $10,000 per year, which is not cost-effective.
Strengths: very low cost as Google earth is free. The Google app is available for most mobile devices and provides a simple interface for basic GPS use.
Weaknesses: data that can be associated with the map is minimal. You can hyperlink to your company's accounts or other online folders. Securing this process is a web designer's nightmare and requires knowledge of HTML, PHP, MySQL, and likely JavaScript. Thus, costs associated with it are primarily due to labor.

Scenario two: online map publishing service like ArcGIS online
maps are created in-house on GIS desktop software and then easily published to the remote ESRI server. Access and permissions are easily controlled at the off-site server.
Strengths: increased power to filter data, i.e. – to find information are looking for. However like Google earth often you must copy and paste records to do any geography or table editing. Publishing the results or changes requires sending the file to the GIS department for inspection and upload.
Weaknesses: limited access to drill down for documents on the home network. Cannot edit geometry in the field so this requires the use of a "map notes" layer that can later be added by the GIS department. Five users for such a system cost about $2500 per year plus potentially other additional charges if a lot of non-editing users visit site.

Scenario three: in-house ArcGIS server
provides both a public and private map interface for the company or city. Can be configured to allow editing in the field and to provide real-time data visualization such as traffic volume per street segment. Solutions are available which allow GPS field crews to update online maps in real time. For heavy volume websites the ArcGIS online map services should utilized as well.
Strengths: the most flexible system available
Weaknesses: the most expensive scenario with implementation costs at about $15,000. However, if the ESRI online map service is not utilized, these costs are incurred only at system initiation and no changes will likely be needed for four or five years, at least. Because of the complex nature of the server environment, skilled personnel must be utilized.