The Manchester Water Safety Review, published following an inquest into Charlie Pope's death last week, found the city centre's waterways to be "broadly" as risky as those in other locations across the UK.
"An overwhelming number of these drownings happened during the hours of darkness. These individuals, all bar two, were men and inebriation played a part in a significant proportion of the events that led to their deaths," the report said.
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Across the UK, less than 30% of people who drown accidentally have alcohol in their bloodstream, according to the Royal Life Saving Society (RLSS).
Earlier this month, it published statistics for 2013-17 showing that 29% of accidental drownings in the UK involved alcohol and/or drug use.
Rospa's report recommended a number of reforms, including improving lighting in some areas, installing fencing at junctions and improving education about routes around Manchester, particularly at night.
The Manchester Water Safety Partnership, which includes the city's police, fire service, council and a number of private landowners, has begun attempting to restrict access to the canal towpaths at night.
It has also installed signs along some city centre canals discouraging people from walking home alone near the water.
"The fact that this partnership exists, and is well established, should be commended," the report found.
The number of drownings in Manchester's canal network has previously provoked rumours and reports about the possible existence of a serial killer called 'The Pusher'.
Greater Manchester Police and the Manchester City Coroner's office have repeatedly denied there is "evidence to suggest the existence of serial foul play".
