The Reedy Creek Improvement District 2023 long-term land use plan has been made public and contains some interesting changes from the previous 2020 plan.
The 2023 plan adds a new category of land usage designation called "Marginally Unsuitable." The plan says that these are areas that have identified or recognized constraints for development. This classification corresponds to wetlands that are within the 100-year flood elevation. Development in these areas is permitted to the extent allowable under the District's Long Term Permits and require compensating storage to be provided. There are 1,731 acres in this category or 13.0 percent of the undeveloped land area.
Looking at the plan above, we can see that the large area to the north of Frontierland at Magic Kingdom has changed from being "Unsuitable" in the 2020 plan (dark green areas) to the new designation of "Marginally Unsuitable" in the latest plan (light green areas). Decoding the designation means that this piece of land has gone from "land considered unavailable for development" to "development is permitted to the extent allowable under the District's Long Term Permits." At the same time, the land immediately next to Big Thunder Mountain has changed from "Suitable" (red) to "Marginally Unsuitable" (light green).
This land designation change may be a significant factor in developing the "Beyond Big Thunder Mountain" Blue Sky concept revealed by Disney Parks' D23 panel Chairman Josh D'Amaro at the D23 event in late 2022. It seems that based on these updated plans, a significant amount of space is available for development, but it will require some extensive work to make the land usable.
According to the Blue Sky concept unveiled by D'Amaro, the new land behind Big Thunder Mountain at Walt Disney World's Magic Kingdom would include Disney animation IPs, including Coco, Encanto, and villains.
Thanks to @danlb_2000 on the WDWMAGIcCForums for originally identifying the changes.
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