Engineers maintained a very gentle downhill slope through channels, tunnels, bridges and settling tanks. Roman systems are famous, but sophisticated water engineering existed in many earlier and contemporary cultures.
What we found
An aqueduct is a system, not just a row of arches. Most of the route may run underground or close to the landscape. Surveying instruments helped builders maintain the gradient, while reservoirs and distribution points controlled flow. Regular maintenance was essential because sediment, leaks and mineral deposits could block the system. The Ridbusters then compare the wording with the original sources, look for the conditions of each observation and check whether another explanation could fit. That turns a surprising headline into a trail a young investigator can follow: claim, test, result and remaining uncertainty. Engineers maintained a very gentle downhill slope through channels, tunnels, bridges and settling tanks.