Alplaus is a hamlet located in Schenectady County, New York, United States. Its name is derived from the Dutch Aal Plaats, or "Place of the Eels." Alplaus is in the southeast corner of the town of Glenville. Some consider it part of the hamlet of East Glenville; however, it is generally recognized as a separate community. Alplaus is, however, part of the East Glenville census-designated place. Census data for the ZIP Code Tabulation Area (ZCTA) associated with Alplaus for the 2000 census had a total population of 431 people in 175 households.