Colosseum - Water Supply to Rome
The first water supply to Rome was via the River Tiber and local natural springs. However the population of Rome  increased and the problem of water supply was resolved through the development of aqueduct technology. The date of the first recorded aqueduct was in the year 312 B.C.  A number of aqueducts were built conveying water from distant springs and streams to Rome. The water in the aqueducts ran gently through concrete channels. Multi-tiered viaducts were developed to cross low areas. Water from the aqueducts passed into large, covered catch-basins in Rome designed to deposit their sediment. The water from the catch-basins were distributed through free-flowing canals, lead and terra-cotta pipes to storage reservoirs and then through lead pipes, called fistulae, to the Romans. A waste-water collection system discharged the waste into the drains or sewer system. The main outlet of the initial drainage system (Cloaca Maxima) was the Tiber River.

Colosseum - Water and Sewer System Requirements
The Colosseum held over 50,000 spectators. The Romans came in droves to watch the death of wild animals, criminals, slaves, Christians and gladiators - terrible, gory, bloody deaths. The massive crowds of spectators at the Colosseum needed to drink - water was a vital requirement in the heat of Rome during the summer. They also needed access to toilet facilities. The gruesome ordeals of animals and humans required an adequate sewer system to dispose of these waste products. The engineers who designed and built the Colosseum had to take these requirements into consideration when building this massive complex. The Colosseum required an ancient  'state of the art' water and sewer, or drainage system designed by the best Roman Engineers of the era.

Colosseum Water System - Drinking Fountains
The Colosseum required drinking fountains to slake the thirst of the Romans, discouraging wine to be consumed in large quantities. Evidence has been found of over 100 drinking fountains in the Colosseum. But how was the water supplied to the fountains? Clues may be found at the Pula Arena in Croatia. The Pula Arena is the only remaining Roman amphitheatre to have four side towers. The four towers had two cisterns filled with perfumed water that fed a fountain or could be sprinkled on the spectators. It is possible that similar towers were erected to supply water at the Colosseum.

Colosseum - Water Supply
Pipes were installed in the walls during the construction of the Colosseum carrying water throughout the complex. Rainwater was collected in the cavea by concentric ducts and poured into vertical pipes leading to the ground floor. Because of a double incline of the floor the water then flowed partly towards the arena and partly towards the outside where it was drained into a brick conduit (60 cm wide and 160 cm deep) which surrounds the Colosseum 2 metres below ground at the bottom of the first step at the base. The Aqua Claudia aqueduct was used to supply water to the area of the Colosseum.   

Colosseum Water System - Toilets (Latrines) and Drains
The Colosseum would have required many toilets, although there is limited information about this subject! There has, however, been evidence found of two very large toilets or latrines in the Colosseum. In the foundations of the Colosseum there are the four underground tunnels and  below them there are four big drains (1.3 by 3.8 metres). These passages were made during the building of the foundations. Communal toilets, or latrines, consisted of a row of holed seats. A flow of water circulated under the seats. A system of small sewers led from all parts of the Colosseum to one great circular drain which surrounded the amphitheatre. At regular intervals along this drain there were wells that reached 8 metres deep. This large drain, in turn, connected to the Cloaca Maxima, the main sewerage system of Rome. A public toilet near the Theatre of Pompey in Rome, that may have seated as many as 100. The open water channel in front of the toilets was used to wash using "cleaning" sponges tied to the end of a stick.

Public Toilets (Latrines) in Rome
There are a couple of interesting anecdotes regarding the public toilets, latrines, in Ancient Rome. The Emperor Vespacian, who commissioned the building of the Colosseum, was the first to introduce pay toilets in the city of Rome to help raise public revenue. When his son, Titus protested that the toilets were raising a stink with the plebs, Vespasian held a coin up to his nose and said, "money doesn't stink." Romans still refer to public toilets as 'vespasiano'. Vespasian also had the produce of the city's urinals collected (urinals consisted of buckets, dolia curta), stored and taxed before being sold to the guild of fullers. Fullers were the clothes cleaners of Rome using the ammonia in urine for its cleaning properties.