Officers conducted 1,142 searches across the region and recovered cannabis, cocaine, former legal high mephedrone and prescription drugs.
In Craigavon, bags of suspected cannabis were discovered buried in a garden close to the home of a suspected drug supplier, who was arrested on drugs and firearms charges.
Assistant Chief Constable Drew Harris said Operation Torus had been ongoing since August 20 and involved districts across Northern Ireland in a stepped-up effort against the trade.
"This is around demonstrating to the public that we take drug dealing and street-level dealing very seriously," he said.
"We recognise that it is a big concern and we have put together resources to deal with this. We need the public's assistance in terms of information now."
Drug dealing is big business and we want to see the police take action against those involved at all levels of the drugs chain.
Searches were carried out across Northern Ireland over the last three weeks and involved additional police, including specialist teams, to gain access to properties.
Areas searched included Belfast, Magherafelt, Newry, Strabane and Craigavon.
A media campaign for information incorporates billboards, Facebook and washroom advertising, and will run until October.
Mr Harris said in combining work intercepting major shipments of drugs, with £11.1 million worth impounded since April, with the street-level operation, police aimed to help suppress the trade.
"The objective is to prevent crime and serious harm, and to make this not a profitable venture for organised crime to enter into - to ruin this as a business," he said.
"We are optimistic with the public's assistance and all the effort we are putting in at both points of the drug market that we can have a positive impact."
He added: "We are recognising that drugs is still a major concern for the community and people are worried about what they see.
"This focuses on the street level and the sale of small amounts of drugs. It is around emphasising to them that we take this seriously."
Police found cannabis in gardens in Craigavon, Co Armagh, near a two-storey terraced property with children`s scooters outside. The hedgerow in the Enniskeen estate had been used to stash easily-accessed supplies.
Officers discovered a firearm in the house, a starting pistol which can fire blanks but may be modified to take a live round.
They arrested a man suspected of possession of a firearm in suspicious circumstances, possession of class B drugs and possession with intent to supply. He was taken from the property gesticulating and shouting abuse.
Officers found cannabis resin worth £30-50 in the garden next door and officers discovered some dealing bags which are used to place amounts for individual buyers.
Suspected cannabis resin and herbal cannabis was found in the gardens, with individually wrapped deals worth about £20 each.
Police describe some drugs discoveries at homes as "transit hides", relatively small amounts brought from a "deep hide" somewhere else with more substantial quantities.
Officers believe there is value in disrupting an individual dealer`s network, incremental steps against street-level crime.
Detective Chief Inspector Stephen Wright, crime manager in Newry and Mourne, Craigavon and Banbridge, said there were regular searches in the area.
"This is business as usual for the PSNI and policing in the district, we do this all the time in response to the intelligence which comes in," he said.
He added they were particularly reliant on public co-operation for carrying out searches proactively.
"We have an impact and we will have a bigger impact if we get more information, the more people tell us the bigger the impact we can have," he said.
The campaign has been welcomed by the Policing Board.
"Drug dealing damages communities and these dealers often prey on young people and those who are most vulnerable," a statement said.
"With the number of drugs seizures having increased by 10% in the past year and the number of people arrested rising, the PSNI are having success in tackling drugs crime."