The Hippodameian Cistern (a tank to collect rainwater), found in the basement of the building housing the Christian Youth Oraganization in Piraeus, is a unique example of the exquisite Hippodameian Water Supply Network.
The size of the Hippodameian Cistern, dated in the 5th century BC, is impressive: it is 10,20 meters high (distance between the top of the cistern and its lowest part at the bottom), while the diameter of its base is 9 meters. The Hippodameian Cistern was a structure including three wells, but only one has been preserved. There is a low gallery, probably closed since the ancient times, which must have connected the cistern with one of the other two wells, at a distance of about 8 meters. The well preserved until today is connected with the cistern through a tunnel 1,70 meters high. Its purpose was to pump the water from the cistern.
The concept of the Hippodameian Cistern can be summarized as follows: collect rain water, filter it and pump it for domestic use. Rainwater entering from the top of the cistern flowed to the center of its bottom, to the sand collector, where it was filtered. Then, the overflowing water of the sand collector basin flowed to the well through the floor of the tunnel. Now the water, perfectly clean, was ready to pump.
The Hippodameian Cistern comprises some technical features that really make it stand out:
- The inclinations and the levels of the floor are such that they ensure that the water would by all means end in the sand collector.
- The materials used for its construction are waterproof, making it impossible for water to vaporize. It’s worth mentioning here that when the Hippodameian Cistern was first discovered, it was filled with water (up to 1/3 of its size) that had to be pumped out.
- To optimize the filtering results – already achieved by the sand collector at the bottom of the cistern – through sedimentation, the bottom of the well is placed lower than the tunnel level.
Today, thanks to the efforts and work of Mr. Yorgos Evangellou, chairman of the Christian Youth Organization in Piraeus, this masterpiece of hydraulics is preserved in excellent condition and is open to the public.
The Hippodameian Cistern, situated in the same block with “Ralleios Lyceum Block”, where remains of the magnificent Hippodameian town and street planning were found, is definitely a must-see!