Analyzing green space using GIS

​The Village of Norridge requires that every residential property
within the Village limits to have at least 65% green space on the
property. This means that the homeowner can only have 35% of the
property consist of impervious surface areas such as the building,
garage, driveway, and patios. Any resident in violation of this policy
can face fines and may be forced to make changes to their property. In
the past, the Village would calculate the green space percentage by
measuring the area of the parcels and the features using a ruler and a
pencil. The Village asked the GIS department to come up with something
that would aid in their analysis.

A map was created showing the percentage of green space for each
parcel in the community. The percentage was calculated by combining all
the building foot prints, driveways, garages, and sidewalks into one
feature then dividing the area of impervious surface in a parcel by the
area of the parcel itself. Even though the number is not necessarily
exact due to some of the features, like patios, not being collected in
the data, it provides a good starting point for any calculations and
allows the village to see what properties may be in violation of the
ordinance and then act accordingly. By using GIS, the village is able to
cut down the amount of time calculating the green space area by hand
and find properties that may be in violation that they might not have
had a reason to check in the past.

Analyzing green space using GIS

​The Village of Norridge requires that every residential property
within the Village limits to have at least 65% green space on the
property. This means that the homeowner can only have 35% of the
property consist of impervious surface areas such as the building,
garage, driveway, and patios. Any resident in violation of this policy
can face fines and may be forced to make changes to their property. In
the past, the Village would calculate the green space percentage by
measuring the area of the parcels and the features using a ruler and a
pencil. The Village asked the GIS department to come up with something
that would aid in their analysis.

A map was created showing the percentage of green space for each
parcel in the community. The percentage was calculated by combining all
the building foot prints, driveways, garages, and sidewalks into one
feature then dividing the area of impervious surface in a parcel by the
area of the parcel itself. Even though the number is not necessarily
exact due to some of the features, like patios, not being collected in
the data, it provides a good starting point for any calculations and
allows the village to see what properties may be in violation of the
ordinance and then act accordingly. By using GIS, the village is able to
cut down the amount of time calculating the green space area by hand
and find properties that may be in violation that they might not have
had a reason to check in the past.