Three bikers careered into a river after trying to escape police called to reports of a roundabout being used for illegal stunts.
West Midlands Police said the riders "rounded off 2017 on a damp note" as they attempted to evade officers in Birmingham at about 3pm on New Year's Eve.
More than 20 scrambler-type bikes were reported to be involved in performing stunts at a traffic island in Hodge Hill, but made off in different directions when police arrived.
Officers arrested three men aged 19, 20 and 24 on suspicion of causing a public nuisance after following three bikes on to parkland off Hodge Hill Road.
Traffic Sergeant Laura Floyd said: "We had several calls from the public concerned that these riders were posing a danger to the public.
"Some reported how dog walkers and people using the park had to take evasive action to avoid being hit.
"Sadly for these three offenders they ended 2017 on a very wet and cold note. And it could get much worse for them next year as we'll be looking to prosecute them for causing a public nuisance."
West Midlands Police has launched a dedicated operation - codenamed Operation Wraithbane - to tackle anti-social off-road biking, and 19 people are awaiting trial charged with causing public nuisance.