ARL and Ithaka S+R have released Appraising our Digital Investment: Sustainability of Digitized Special Collections in ARL Libraries .
Here's an excerpt from the press release:
The research reveals that understanding the continuing costs for sustaining digital collections is a challenge across libraries. Responsibility is frequently dispersed among departments, and staff time and other costs are rarely allocated expressly to these activities or accounted for project-by-project. Almost universally, libraries are funding this activity out of their base budgets, suggesting that they will continue to need to shift funds from other things in order to support this as a priority.
While libraries are supporting these collections within their operations, the study's findings also reflect concern over sustainability, with librarians citing lack of funding and staff capacity as major challenges to sufficient investment in their digital collections. . . .
The three-part survey, designed with input from the ARL community, was sent to all ARL member libraries in the US and Canada and completed by 89 library directors, a response rate of 70%. In addition to the institutional perspective provided by library directors, library staff responded to other sections to offer insight into activities and costs for all of their institution's digitized collections, and questions about individual projects.