In EYDAP’s Historical Archive a variety of documents are preserved that reflect the multiannual history and successive operation of the Company (through Athens and Piraeus "Greek Water Company S.A." and the "Athens Sewerage Authority"), as well as the relationship between the progress of the water supply and sewer system and the development of the Athenian society.

The Department of Corporate Responsibility & Historical Archive was established in 2016 and is responsible for the collection, storage, management and exploitation (recording, documentation, digitization according to international standards, and the creation of appropriate conservation conditions) of EYDAP’s Historical Archival Material. The Department of Corporate Responsibility & Historical Archive falls under the Division of Communication & Corporate Affairs.

The work of the Historical Archive is part of the actions of EYDAP’s Culture Network, which expresses the wider effort of EYDAP to develop a unified cultural identity and policy with the aim of creating actions that promote EYDAP’s history and supply the society network with educational and cultural benefits.

The proper management of the archival material of historical importance consists of a tool for the study of the history of Greece, the provision of easy access to knowledge and the creation of the essential context for its exploitation.

Within this context, EYDAP has a "Historical Archive Management Policy", which includes among other things, the procedures for the management, acquisition and public access to it.