Photographs of the municipal flag of Santo Domingo Este can be found online, with one of them here. The flag features the coat of arms of the city centered on a white field. The coat of arms shows a scene by the ocean with a rising sun. Above the shield in green letters are the words "Santo Domingo Este," with the letters "ASDE" below the shield in similar lettering. Randy Young, 20 December 2015
Santo Domingo Este (East Santo Domingo) is the capital of Santo Domingo province and is located on the outskirts of the Dominican Republic's capital city of Santo Domingo de Guzmán. Santo Domingo Este was created as a separate city in 2001 with Law No. 163-01 that split Santo Domingo province into the current province and the Distrito Nacional, which houses the actual national capital.
Source: Wikipedia article Randy Young, 20 December 2015