In a large and prosperous ancient city, and Side was undoubtedly one of those, a system of supplying water to its inhabitants played a very important role. The water brought to the city was supplied to the baths and private residences. In the Roman period the problem of providing water of appropriate quality to the cities was solved by building aqueducts and city residents obtained drinking water from public fountains. The wealthiest citizens had running water and a sewer system at their homes, so that they did not need to use the fountain at all.

The aqueduct supplying water to Side was, most probably, built at the end of the 2ndcentury AD. In the 3rd century it underwent a complete renovation, financed by a wealthy citizen called Lollianos Bryonianos and his wife Quirinia Patra. The water came from the river Melas, today called Manavgat Çayı, flowing from the slopes of the Taurus mountains and then was transported through the distance of 40 km to the center of Side. In our times, certain sections of the aqueduct, are still visible. A special opening in the city walls where the pipe entered Side can be seen. Flowing water was further distributed to the baths, fountains and cisterns. In the area of Side fragments of pipes and water channels made of marble, lead and terracotta have been identified.

The most important nymphaeum in Side is situated opposite the main city gate. It was built in the same period as the aqueduct. In its heyday the three-storied nymphaeum building was adorned by the richly decorated facade, rising above the water tank. The lowest floor of the structure, which contains three niches, is still standing. In ancient times the water flowed through the openings in this structure. The statues and reliefs that used to adorn the nymphaeum are now exhibited in the local Archaeological Museum in Side.