GIS Assists in Locating Permissible Areas for Medical Marijuana Facilities


The state of Illinois recently enacted a law that legalizes medical marijuana. This highly controversial law has forced communities around the state to scramble to determine where potential areas are located where it’s permissible for an individual to open a dispensary or a cultivation center. State law requires that a cultivation center cannot be located within 2500 feet of a school, daycare center, or any residential zoned property. A dispensary cannot be located within 1000 feet of a school or a daycare center, or within a residential zoned property. In order to determine these locations, the City of Park Ridge utilized its Geographic Information System (GIS) to determine where permissible areas for these locations might be allowed in the city under the new law.

Using a number of tools available in the GIS software, four maps were created for this project. The first map displayed locations for potential cultivation centers. Due to the 2500 foot restrictions described above, every inch of Park Ridge is considered "off limits" to a new cultivation center being built. The second map showed locations for a potential dispensary. Since the restrictions for opening a dispensary are not as restrictive as a cultivation center, a number of potential locations were identified. The city then wanted to narrow down the possible zoning districts where a dispensary would be allowed into the B2 and B3 districts. Maps were created to show the potential locations that fell within these two zoning areas. Using this information, the City of Park Ridge can now determine any potential areas for a dispensary and plan accordingly.

Salt Distribution and Conservation Mapping

​This year’s extremely cold and snowy winter has left the vast majority of municipalities in the Chicago area with a shortage of salt, including the Village of Oak Brook.  In an effort to preserve salt supplies, Village staff was asked to come up with a salt conservation plan that would stretch their current supply as long as possible.  Many communities in the area had it worse and were forced to not salt any residential streets or were forced to use a sand/salt mixture which can have an adverse effect on surround ecosystem.  It was determined that Oak Brook had enough supply left to salt busy and trouble areas, but not enough to salt long stretches of residential subdivisions.  Based on this initial assessment, the next step was to identify the trouble areas that need to have salt and inform the snow plow drivers where they should and should not salt during and after a winter weather event.

It was determined by public works staff that the best approach to this issue was to work with the Geographic Information System (GIS) department to identify and map all intersections, steep hills, and heavily traveled roads.  As shown in the above image, areas that need to be salted are clearly highlighted in red for drivers to use as a guide while plowing during future storm events.  Using these maps as a guide, this conservation initiative allowed for the Village plow drivers to spread approximately half the salt as they normally would in a typical snow event. 

By using GIS to display this information, the Village not only provided their drivers, administration and emergency services with a clear image of what areas are being salted, but actually conserved salt and developed a plan that can be easily implemented in similar situations in the future.

Using GIS to Assist with Home Sales Analysis

The Village of Oak Brook is currently directing an initiative for residential enhancements to help improve home values, fill vacancies, and attract new families to the Village.  In order to do so, they have created a committee seated by both Village employees and residents, as well as hiring a consultant to formulate and analyze a survey filled out by residents.  In addition to these two initiatives, the Village wanted to analyze sales over the past five years in an effort to discover trends pertaining to location, time, cost, and size of recent residential home and property sales.  This information, in combination with the survey and community input, is going to help steer the Village in the direction of improving its already renowned reputation as a leading community in DuPage County for families to reside in.

In order to perform the home sales analysis, a list of all home/property sales over the past five years was requested from the County Recorder’s office.  Once the list was acquired, Geographic Information System (GIS) staff was able to map out and match all home sales to the existing address data within the Village.  Once everything was in the system, the GIS staff was able to cross reference the data with other GIS information, such as subdivisions, property boundaries (to determine size), and zoning (single or multi-family).  This allowed for the easy creation of multiple themed maps and statistical spreadsheets.  In addition to this analysis, GIS staff was able to create over a dozen maps which display the density of home sale dispersal across the village based off of a given category from the data.  The above image displays the density of sales from 2009 to 2013 that were between 1 and 2 acres of land.  This map, along with the dozens of other maps and statistical spreadsheets, are serving as an instrumental role for decision makers in the Village to be more information as they plan for the future.

More information for better decision making

The Lake County, IL Assessors Office has a database of information about properties that is a useful resource for numerous local municipal operations.   This information includes details about the structures on a property, assessment values, and other general information.  Having access to this type of information would be of tremendous value to a local government.  Therefore The Village of Mundelein, IL requested this database from Lake County and then asked the county Geographic Information System (GIS) Office to create a useful way to view this information natively in the village’s GIS environment. 

The county GIS Office created a layer of information from the Assessor database and provided it to the village GIS staff for use.  This layer was then added it to the village’s web-based mapping application, MapOffice™ Web Access, as a custom layer for display.  The intent of the overlay is to expose this information to village staff to give them the opportunity to brainstorm additional ways that it can be used moving forward.   One current idea is to push this information into the village’s CityView application during the next software upgrade.  This will provide inspectors with quick access to information about structures, as well as other useful structural information.    Another idea is to create maps showing the Equalized Assessed Values (EAV) of properties and the age of structures within the Village.

By using GIS, the Village developed an easy way to view rich detail of each property.  This is a more efficient way to access the data other than clicking on each property and waiting to link to a report from the Assessor’s office.   By creating a custom overlay to view in the village mapping environment, village users can interact with the data more directly and better visualize potential future products.

Water main Repair Frequency

​Since the late 1970s The Village of Mundelein, IL has aggressively replaced older ductile iron water main with PVC watermain.  This has resulted in a safer water supply and a lower maintenance cost water system.  There are still a few areas of the Village with older ductile iron water mains and these areas also tend to have the highest frequency of breaks. 

The Mundelein Public Works Department desired an effective way to show the Village Board that they need to dedicate funding to replace the older pipes in these few remaining areas.   They contracted the Geographic Information System (GIS) Office about creating a map the shows the locations of breaks and the age of the pipes.  The GIS Office created a map showing the density of water main repairs, which displayed breaks grouped in a few specific areas.  Next they symbolized the water mains by year and material to show which ones are new or have been replaced and which water mains are still original.

When the water main repair density information, which showed which pipes where new or replaced, was visually compared to the general water main data, it was immediately clear that all the repair issues were located in areas that still contained original water mains.  Now the Department of Public Works had a visual display that clearly showed that the primary problem areas are those that contain most of the older water mains.   Public Works intends to use this map as a visual resource during future council meetings, where they plan to request funding from the Village Board for replacing these problem mains.