We conducted a survey in collaboration with the Chungcheongbuk-do Office of Education to assess the current status of collections in public ibraries affiliated with the Office of Education. The objective of this survey was to identify the current challenges and determine when these libraries are expected to reach a state of collection saturation. Libraries under the jurisdiction of the Chungcheongbuk-do Office of Education are currently facing significant challenges due to severe collection saturation. This underscores the pressing need for the systematic expansion and operation of a collaborative preservation library for a swift response. In the future, it appears that the focus during the transfer process will primarily be on transferring collection-oriented materials. Given the difficulty in providing preservation facilities at individual library levels, materials with reservation value, such as rare books and specialized resources, will need to be transferred to the collaborative preservation library. Additionally, the development of policies and regulations related to material preservation seems necessary. Furthermore, when transferring materials to the collaborative preservation library in the future, it appears that criteria for material transfer will be needed, particularly concerning issues such as a decrease in usage rates for less frequently accessed materials. Subsequent research should consider conducting a survey on the collection saturation status of public libraries under local governments in order to assess the overall need for collection expansion in all public libraries within Chungcheongbuk-do