An Application of the Land Suitability Analysis Technique

The Work of Masters

As part of the Master’s Program in the Department of City and Regional Planning at UNC, Chapel Hill, each student pursuing a Masters of City and Regional Planning Degree must produce a Master’s Project in their final year. This often involves original research, work with community stakeholders, and advanced quantitative or qualitative techniques. The intention is to “demonstrate the student’s capabilities and readiness for professional practice by requiring a final project of professional quality” (UNC DCRP). Below, Kayla DiCristina, a graduate of the class of 2019, introduces her project.


An Application of the Land Suitability Analysis Technique

This paper utilized the land suitability analysis (LSA) technique to determine the most appropriate areas for three different uses: pure conservation, working forest operations, and residential/hospitality developments. The author applied this technique to a site in Northeastern Maine. A non-profit company owned the site and the author worked in conjunction with this entity to complete the study. The overall goal of this application was to incorporate the needs of the adjacent town and non-profit owner into an analysis that could justify future land use decisions. The site required a strong analysis because the non-profit company had reached a standstill in development on the property. This standstill resulted from a clause in the purchasing contract that required approval by the adjacent town to modify the property.

One of the sites under consideration in Northeastern Main

The land suitability analysis technique is the algebraic addition of different factors weighted against each other to provide a score that shows how suitable a piece of land is for different uses. Charles Eliot and his associates developed this technique in the early-1900’s. Eliot and his associates used hand-drawn overlay maps to determine the suitability of an area. Ian McHarg further refined the land suitability process with his book Design with Nature. McHarg utilized transparent maps with a combination of light and dark values to superimposed the maps on top of each other to create a composite suitability map.

The author of this paper used a four-part methodology to perform this land suitability analysis. The primary software used for analysis was ArcMap v. 10.1.6. Data was formatted into a raster form with 30m x 30m cells. The methodology described was repeated for each use: pure conservation, working forest operations, and residential/hospitality developments.

Land Use Analysis 1
Results of a Land Suitability Analysis for Pure Conservation


To begin, the author developed unique criteria for each use. Criteria were based on the goals of the adjacent small town, the literature reviewed, expert opinion, and the current state of the site. Two types of criteria were developed: mandatory and desired.  Mandatory criteria were those criteria that automatically rule out a parcel due to the presence or absence of a feature. Desired, criteria were those criteria that contribute to the suitability of an area in the land suitability analysis process for each use. Next, the author collected data to measure each criteria. Data primarily came from Maine’s GIS repository. Following the collection of data, the author and non-profit company weighted and ranked each criteria.

Results of a Land Suitability Analysis for a Working Forest

In a land suitability analysis, criteria are weighted to determine the level of importance of a criteria compared to another criteria. The author created a weighting exercise based on a similar land suitability analysis performed on the Upper Neuse River Basin. The author solicited information from experts in the partner non-profit company. Experts were instructed to assign dollars to the criteria they believed were the most important given each individual use. These monetary totals were then averaged across all input solicitations to create the weights for each criteria. Weighting was only done for the desired criteria since mandatory criteria do not contribute to the overall suitability score and were used to automatically rule out parcels from the analysis. Finally, the author completed the analysis with the criteria and weights by utilizing the map algebra tool in ArcMap. This tool combined the criteria and weights into an algebraic formula that identified the areas that were best for each use.

Land Use Analysis 2
Results of a Land Suitability Analysis for Residential/Hospitality Development

Upon completion of the analysis, the author identified two areas on the site that were best suited for each use. These areas received the highest suitability score and were often linked to a determining feature, such as a wetland. This study serves as a resource for the adjacent town and the non-profit owner to continue their conversations about the future of this property. This study also serves jumping off point for further in-depth investigation. Since the property is large, smart decisions must be made about allocating resources to investigate the appropriateness of an area for a use. For instance, rather than having a surveyor investigate the entire site, having the surveyor investigate two smaller areas is a smarter use of resources. Following the completion of this study, additional town meetings were held. Utilizing the results of this analysis, the adjacent town and the non-profit owner were able to reach an agreement on a number of future land use decisions on the property. The adjacent town eventually signed off on approval, thus, ending the stalemate that was once a defining feature of this project.


About the Author: Kayla DiCristina holds both a Bachelors and Masters in urban and regional planning. Her experience focuses on GIS analysis and environmental studies. Within the planning field, she is most passionate about land use decisions that maximize both economic and environmental goals.