The Holy Brook got its name from the fact that it powered the watermill of Reading Abbey.
It leaves the Kennet at Theale and runs separate from the river until it rejoins just downstream of the Abbey Mill by the prison. A side stream from it runs into the Kennet again at Calcot.
It is not clear whether it is a natural watercourse or one made by the monks especially to drive their mill. There were many watercourses through Reading in mediaeval times and other watermills, all open to the air and to be seen on early maps. That part of Reading was called Seven Bridges. Now all these watercourses, apart from the Kennet have been covered over or culverted and run under the streets of the town. The early maps of Reading show the gradual culverting.
The first part of the Holy Brook to be culverted appears to have been the stretch to the west of Bridge Street where there is early brickwork and also many stones from the demolition of Reading Abbey around 1550. The documents on the Abbey tell of stone being reused for the bridges of Reading.
It then flowed through the Oracle workhouse which was built for the poor and elderly of Reading to find a source of income by a gift in the will of John Kendrick, a wealthy local business man. The workhouse was called the Oracle and put up in 1628. The Gates are on display in the Museum with the initials IK and 1628 on them. The Oracle was built of local brick and spanned the Holy Brook which ran open to the sky through its central courtyard. The stream was later bricked but with the building of the new Oracle shopping center the Holy Brook has been opened to the sky again.
For more information on the Oracle click here.
At the Oracle it can be seen going underground again and its runs under the Ship Hotel, under Duke Street and emerges at the front of the library in Abbey Square. In Abbey times the south Gate was just to its north here and the Abbey Precinct Wall ran long its north side. It can be seen running under the Mill Arch which is the one remaining from the Abbey Mill which straddled the Holy Brook until it went out of use in 1957 and was demolished in 1959. It was an undershot waterwheel, the water running under the wheel rather than over the top.