Guest Authors: Margaret Minzner and Lauren Kleve, OKI Regional Council of Governments
This guest blog post from a partner organization or individual reflects the work and opinions of the author and does not reflect action taken by Green Umbrella staff or board.
The Green Umbrella Greenspace Action Team, formed decades ago, actively sought to define Greenspace, map a proposed Greenspace green print, map the regional Greenspace and measure the change in Greenspace over the years. The team was successful, exceeded goals, and ultimately started to focus attention on the next steps.
In 2018, the team had lengthy discussions about how to use the existing Greenspace layer to best plan for Greenspace in the region. As the Action teams transitioned into Impact Teams, a subset of the team decided to tackle how the region should prioritize Greenspace. Prioritization of Greenspace is complicated because priorities can vary. For instance, an Urban Greenspace may not have high biodiversity or endangered species but could be vital to areas with limited Greenspace. On the other hand, in areas with ample Greenspace, the criteria of what should be protected might be high. Also, each partnering organization for a project may have different priorities, so it was decided that a suitability model would best assess and prioritize areas for conservation and protection.
At the same time, the Ohio-Kentucky-Indiana Regional Council of Governments (OKI) was considering a similar project. OKI is a council of local governments, business organizations, and community groups committed to developing collaborative strategies to improve the quality of life and the region's economic vitality.
OKI is responsible for developing a Discussion on Environmental Mitigation as part of its regional transportation planning. The discussion considers potential mitigation activities and areas for their regional application, which may have the most significant potential to restore and maintain the environmental functions affected by the regional transportation plan. One outcome of the Environmental Consultations was a discussion on regional mitigation needs.
Environmental Mitigation and Suitability Modeler Workshop participants learn and run their models.
Through the Environmental consultations, a need to help identify potential environmental mitigation projects in the region was brought to OKI’s attention. There is a concern that the service areas extend outside the OKI Region, but much of the environmental impact occurs within the OKI Region. OKI saw an opportunity to support efforts to find potential mitigation projects within our organization by providing more detailed mapping capabilities. However, this effort needed to adapt to many needs in the region. OKI used an approach that leveraged data and analysis, allowing the end user to model different potential scenarios. An adaptable model was needed to respond to the needs of stakeholders within three states, eight counties, two USACE Districts, and multiple compensatory mitigation service areas with different expectations. While there are similarities in the layers used for analysis, often, potential mitigation projects focus on impaired sites suitable for restoration vs. high-quality areas for protection.
Since this model would have multiple applications, extensive research was required. The requirements for what makes an excellent environmental mitigation project can differ depending on the type of mitigations (Stream, wetland, species) or even between states. In 2021, OKI interviewed agencies to determine the level of analysis needed, layers to include, etc. Everyone had different ideas of what needed to be included in a prioritization model. Three draft versions were presented to stakeholders before settling on the final modeler. In Fall 2021, OKI followed up with a final presentation to the participating agencies to view the product before releasing online.
OKI identified GIS layers that should be included in the model through Consultation Efforts. The layers included many federal datasets, which were important in the model (21 total). They have more specific stream data (impaired and parcels with stream length greater than ½ mile) and local Urban Tree Canopy data. OKI used federal or state datasets whenever possible so that others could build similar models without developing their own datasets. In this model, EPA’s EJScreen (Environmental Justice) layers were used so that suitability analysis could include EJ demographics, traffic exposure, respiratory health issues, and cancer incidence.
The Environmental Mitigation and Suitability Model (EMSM) works using a Weighted Raster Overlay or WRO. The WRO combines several raster layers based on user-defined layers' weights and classes within each layer. Each raster layer is assigned a weight in the suitability analysis. Raster layers are overlaid, multiplying each raster cell's suitability value by layer weight and totaling the values to derive a suitability weighted value or score. These values are written to new cells in an output layer displayed as a new raster with pixels rated 1-9, with nine the most representative of the model.
The EMSM was released in fall 2021. Since then, there have been multiple workshops and training to promote use for local government planning, developers, and conservation groups. The tool has been used over 1000 times in the past year. Some of our partners have shared their purposes for using the model, including:
An in-lieu fee provider using the tool to find potential stream mitigation sites
A tree planting initiative that used the equity indicators and canopy cover to find communities for tree planting initiatives
A soil and water conservation district using the tool to predict where there may be bat habitat
Since the application was created in-house with federally available datasets, the EMSM has become a great example of how to bring high-level suitability analysis to communities that might not otherwise have access to the software and the training required. This project has also been presented at several regional, national, and even international events, including the Midwest Sustainability Summit, ESRI’s Geodesign Summit and Users’ Conference, The National Mitigation and Ecological banking Conference, and the International Conference on Ecology and Transportation, so that others might be able to develop their own models building on our work.
As with most web applications, thoughts on updates emerge almost as soon as the application is released. There have been updates to the Urban Tree Canopy dataset, additional data layers from the EPA EJ Screen, and scheduled data updates and maintenance. Additional functionality is also being considered for the next update, but the most critical next steps involve the continued promotion of this tool to local communities. The Green Umbrella Greenspace Impact team is currently planning on how the tool can be used regionally to support a regional greenspace conservation/restoration plan.
If you have any feedback, questions, or want to see other layers represented in the Environmental Mitigation and Suitability Model, please contact Margaret Minzner by email at MMinzner@oki.org.