Challenges remain in optimizing the use of increasingly large inflows of climate adaptation articles and guidance documents to improve coastal science and engineering practices. In addition to four major academic databases, the large grey literature was quantified by analyzing web sources of hundreds of government, nonprofit and university reports not previously included in reviews. Three spatial scales were examined for differences in amount and timing of adaptation documents: (a) between region (southeast and northeast U.S.); (b) among sub-region (Florida and Carolinas; New York/New Jersey and New England); and (c) among states (ten states total). Comparisons were also made across spatial scales for document sources (academic journals, government, non-governmental organizations (NGO), university, mixed sources), including four governance subcategories (federal, state, regional and local). Differences were identified among some spatial scales in academic vs. grey literature and among categories of grey literature. 53% of the literature was from grey sources (21% government, 10% university, 8% nonprofit and 14% mixed sources). This literature can be large and is grounded in applied, experiential knowledge, yet is unavailable in almost all academic databases. These relatively hidden documents provide insight into on-the-ground science and engineering case-histories, policy innovations, and power relationships across scales of geography and governance.