The earthquake and the resulting tsunami on December 26, 2004, damaged the freshwater supply system in the coastal areas of northern Sumatra. In response to this natural disaster, the German-Indonesian HELicopter Project ACEH was initiated to assist the Indonesian government in its effort to plan and realize a sustainable reconstruction of community infrastructure by providing geophysical and hydrogeological data to serve as a basis for spatial planning. After two successful airborne geophysical surveys funded by the Federal Institute for Geosciences and Natural Resources of Germany, conducted on the north coast near the city of Banda Aceh and along the west coast between the towns of Calang and Meulaboh, Coca-Cola Foundation Indonesia funded an additional survey on the northeast coast around the town of Sigli. Helicopter-borne electromagnetics (HEM) revealed shallow freshwater resources up to several kilometers inland. Along the coast, however, the investigation depth of the HEM system was constrained due to near-surface saltwater. Here, ground-based transient electromagnetics was utilized on several profiles close to the town of Sigli, revealing deep coastal freshwater resources. The combination of airborne and ground-based electromagnetic techniques has proven to be highly effective to estimate the freshwater potential of the Sigli marshlands. Numerous sites for planned water wells could be identified as promising freshwater sources and approximate drilling depths provided.