This story has always made me laugh, and shows that problems with builders are not a modern phenomenon. Nor are problems with large public projects.
A Roman inscription (CIL VIII 2728; found at Lambaesis, now at Bejaia) tells of difficulties connecting the water supply at Saldae in Mauretania Caesariensis, Algeria.
In the second century AD the Toudja Aqueduct was built to feed the fountains and many public baths of this Augustan colony. Most of the aqueduct channel was raised on arches above the ground, but some of it had to run through a 428 m long tunnel cut into a hill.
A Roman engineer had a bright idea - if they dug the tunnel from both ends simultaneously, it would speed up work. Unfortunately, the plan did not work because after four years of digging, the two tunnels failed to meet up. The inscription on a cippae tells us that in AD 150 the governor of Mauritania had to ask Marcus Valerius Etruscus, Legate of the Third Legion in Numidia, to "send back" Nonius Datus, an engineer (recently) retired from the Legion.
Nonius succeeded in resolving the problem by building a transverse channel linking the two tunnels, and Saldae's water supply was connected. Nonius has also left us his own account of the story, preserved in a second inscription on the cippea (CIL VIII 18122), where he blames the contractors, not himself as engineer, for the mess.
Nonius is often credited with 'solving' the problem of two tunnels in AD 152, but if you read the inscription, he also seems to have instigated the scheme in AD 137.
This is the sort of anecdote that makes the Romans more approachable, and would not have been known had the inscriptions not been preserved. The little on altar on which they are carved is decorated with carved figures labelled: Patientia, Virtus and Spes (Hope).
Article about the inscriptions:
J.-P. Laporte, Notes sur l’aqueduc de Saldae (Bougie), L’Africa Romana, 11, 1996, p. 711-762