A detailed open space evaluation was performed on selected undeveloped parcel groupings greater than five acres in size in Grosse Ile Township. The purpose of this evaluation was to determine which properties, if any, should be purchased by the Grosse Ile Township Open Spaces / Greenways Program, for preservation. As part of this evaluation, a ranking system was developed for identifying and evaluating other privately owned vacant property on the island that are less than five acres in size.

To accomplish this goal, we used geographic information systems (GIS) technology to build a geographic database, instead of relying on the use of traditional site visits, which can be costly and time consuming. This geographic database contains the data layers, which can be queried to evaluate each selected parcel for established criteria. To perform this evaluation, two phases were required.

Phase I: Build the GIS database using appropriate data layers. This tool was used to answer a series of questions or queries about each property in Grosse Ile Township.

Phase II: The evaluation was performed using the GIS constructed in Phase I. A written report presented a list of the properties most beneficial to the Open Space / Greenways Program, based on the established criteria and ranked in priority order. The detailed description for each parcel or parcel group includes a map and summary of the evaluation criteria used for that particular parcel or parcel group.