Officers have slapped the order covering Camber and Broad Street until 6.55pm today (Thursday) amid threatening behavior spiraling into the scorching heat.
Young hooligans jumped out of the Camber into dangerous waters, littering, committing criminal damage and launching a torrent of abuse against local facility staff.
A police spokeswoman said: 'We are aware that these incidents are caused by a very small minority of our young population, and we would like to thank those who enjoy the area safely in the warmer weather.
'We are using the dispersal tool as a means to address the rise in antisocial behavior, while supporting local residents in line with our commitment to keeping our communities safe.
โWhile our teams have been conducting additional patrols in the area, we are now also making use of a Section 34 dispersal order.
"We will continue to review this and another dispersal order can be implemented once it is finished if deemed necessary."
She added: 'The dispersal order gives our officers the power to order a person to leave the area for a period of 48 hours without return. Refusal to comply with the order is a crime.
"Children under 16 will be taken home and follow-up work will be done with the parents."
Portsmouth South Insp Louise Tester said: โWe know from talking to residents and businesses in the area how much antisocial behavior of this type can negatively impact people's lives and this is simply not acceptable.
Furthermore, jumping off the Camber in a working shipyard is incredibly dangerous for those involved and for those around them.
โWhile we have ensured that we have expanded our patrols in the area, we also believe that using these powers to disperse groups of people will help us further address this issue.
โAfter such a difficult year, we want everyone to be able to enjoy our city safely and we will ensure that we work solidly to address these antisocial behavior issues so that this can be done.
"We want to assure our communities that our main job is making our neighborhoods safer for everyone is our priority."
Anyone who witnesses antisocial behavior in the area should call 101 or report it to the police online at www.hampshire.police.uk. If a crime is being committed, call 999.
