The Environment Agency has said a fault in the software which operates the sluice gate in Twerton was to blame for the dramatic river level drop which caused boats to sink on Tuesday 15th September.
The water level in the River Avon dropped by around 1.8m on Tuesday evening, leading to boats being partially submerged and sinking.
In a statement, the Environment Agency said: “Staff have investigated to find out what happened and it appears a fault in the software which operates the vertical sluice gate caused it to open suddenly, causing the river level to drop 1.8m.”
Ian Withers of the Environment Agency said: “This is very distressing to see so many people who rely on their boats as their home to suddenly become stricken and unable to access their property.
“Fortunately, it appears no one was harmed and the hard work of righting this situation has begun.
“An incident like this is unprecedented. But with the support of B&NES, the Canal & River Trust and Avon & Somerset Police steps are being taken.
“The first is welfare and accommodation, which has been offered to those in need of a place to stay, with facilities now on site for those who have chosen to be near their property.
“We are holding the river upstream while engineers contracted by the Canal & River Trust begin inspecting each boat to see if it will float or if repair is needed first.
“While this operation continues, it is obviously necessary for us to keep the river upstream and it will likely take several days. Once done, and everyone is satisfied no further damage will be caused, the river will be released in a safe and controlled manner.”
Boat owners are being advised not to attempt to access or interfere with the stability of their vessels while they are in their current dangerous condition until they have been assessed.
Emergency services were called at around 6.45pm on Tuesday evening to reports of the water level in the river dropping, causing some boats to tip over.
Crews from the Bath, Bedminster and Temple fire stations were mobilised to the incident, assisting boat owners with the swift water rescue team.