The issue of ‘county lines’ for drugs was raised by city councillors at a community affairs committee meeting yesterday.
Divisional manager for communities at Chichester District Council, Pam Bushby raised the issue at last night's community affairs committee.
She said in the reports compiled by community wardens for the city centre, south, east and west wards, drugs featured 'quite heavily' in each and especially in Chichester west.
Ms Bushby said that a more worrying issue was 'county lines', where drugs are brought into the area from London.
The charity Crimestoppers says that county lines refers to gangs and organised criminal networks which export illegal drugs into suburban, rural and coastal areas, using dedicated mobile phone lines or 'deal line'.
Ms Bushby said: "We are working very closely with police colleagues and housing colleagues and with our registered providers to ensure their staff are well aware of what is going on. Community wardens are putting in regular intelligence reports."
"It is very difficult with drugs for the police to say, whether or not they are doing any specific operations when they are looking at warrants for properties they're not going to be sharing that information and they'll be making sure those warrants are being executed without peoples' knowledge because what they don't want to do is disturb the activity that's going on and actually catch them in the act.
"We often don't get to hear anything until after the event because it does appear to the public that there is nothing happening but we have been assured that there is activity going on behind the scenes and there is action being taken.
"We have been encouraging residents that if they see something, to say something."
She added: "It is not going to get resolved quickly. It's a worry but it is something that is affecting every single coastal strip from Margate to Cornwall."
"We are working along side other district councils to stop it."
A police spokesman said the phenomenon is not new. They said: "London affiliated gangs have been seeking to establish drug distribution in East and West Sussex ad elsewhere in the South East, for several years."
"The areas in Sussex most affected by the drug trade from London are the larger coastal towns, with established drugs markets that can be exploited locally, namely Hastings, Eastbourne, Worthing, Bognor Regis and Brighton, but also towns such as Crawley.
"We actively target such drug dealing on a forcewide, divisional or district basis wherever it is identified and there have been many examples of successful disruption and convictions of dealers.
"They tend to use a local property, generally belonging to a vulnerable person, sometimes drug users, as a base for their activities. This is known as 'cuckooing' and will often happen by force or coercion. In some instances victims have left their homes in fear of violence.
"Sussex Police, working with the Metropolitan Police and the Home Office, were the first force in the country to use a new law aimed at curbing the use of phone lines by organised crime groups to distribute drugs.
"The force works closely with law enforcement partners, including the National Crime Agency, the South East Regional Organised Crime Unit, British Transport Police and neighbouring forces, to deal with the known threat of drug dealing stemming from London."
Anyone who has suspicions or information about drug dealing in their community or wider afield can contact the police at any time online (https://sussex.police.uk/contact-us/report-online/) or by phoning 101.
Alternatively, visit crimestoppers-uk.org or contact the independent charity anonymously on 0800 555 111.