The Pego do Altar Dam, originally named Salazar Dam, is a dam built on the bed of the Ribeira das Alcáçovas, in the Sado River basin, in the parish of Santa Susana, in the municipality of Alcácer do Sal, Portugal.
The Salazar Dam was built in 1949, during the Estado Novo period, to harness the waters for agriculture in the Sado Valley (rice fields of Alcácer do Sal) and for hydroelectric generation. Its reservoir is now a point of great tourist interest, particularly for sport fishing.