Gardaí are to target day trip and weekend destinations favoured by Dubliners to discourage an exodus from the capital.
Officers will set up checkpoints around the perimeter of Dublin as well as surrounding counties this morning to ensure the public comply with the Level 3 Covid-19 restrictions imposed by the Government.
However, they will not repeat the motorway operation that marked the Easter lockdown.
Instead, the garda focus will be on the destinations rather than the roads being used by those seeking to head to the Wicklow mountains and other spots within commuting distance.
"We want to avoid long tailbacks of traffic as a result of motorway checkpoints," a senior officer said.
"These will be replaced by carrying out the checks locally at the areas where crowds are likely to gather for relaxation."
Gardaí will also monitor increases in passengers on the Dart, Luas and other routes.
Officers will be on duty at rail stations to establish the motives of those hoping to spend time outside the capital, either as sightseers or to avail of more relaxed restrictions on pubs and restaurants in surrounding counties.
People from outside the county are being advised not to travel into Dublin during the three-week period.
The existing high-visibility patrolling plan for Dublin, where officers will be out in force, will be stepped up over the weekend to encourage compliance with the new Level 3 regulations.
Gardaí will also make spot checks in pubs to inspect food bills and establish how much is being spent on the required €9 meals and determine if the premises are observing the rules.
Visits will also be made to selected premises to ensure they are closing on time.
The officers will encourage the public to co-operate with the guidelines on social distancing and avoid large groups assembling on the streets or pavements.
If gardaí encounter potential breaches of the regulations, they will investigate and then prepare a file in each case for the office of the Director of Public Prosecutions.
Deputy garda commissioner in charge of policing and security, John Twomey, reiterated that gardaí would continue to adopt a graduated response based on the force's tradition of policing by consent.
He said this had resulted in officers being seen to engage, educate, encourage and, only as a last resort, enforce - and that is the approach that would continue.
Meanwhile, acting chief medical officer Dr Ronan Glynn warned that 80 people are in hospital with Covid-19 across the country compared with 20 people a month ago.
"If we do not interrupt transmission now, we are concerned that we would have upwards of 1,000 cases a day, at least half of which would be in Dublin, by October," he said.
"I'm asking you to take action now. Prioritise who you need to see. As a rule of thumb, plan to see half the number of people this week that you did last week."
Taoiseach Micheál Martin said: "We are in a very urgent situation. We need to act now and act decisively.
"We need to act now for the common purpose and the common good. We owe it to the memory of all those taken by the virus.
"We did it before, with Laois, Offaly and Kildare, and we can do it again. This too will pass."
Tánaiste Leo Varadkar said the situation is "getting serious again", and if it is "not nipped in the bud, more people will get sick".
"It's not all bad and there is hope. If we compare with our neighbours, we are all doing relatively well," he said.
Those laid-off today or tomorrow are eligible for the Work Subsidy Scheme or Pandemic Unemployment Payment, Mr Varadkar added.
"Today we are releasing an additional €30m business start-up grant," he said.
An additional €5m will be allocated for tourism, culture and sport, administered by Culture Minister Catherine Martin.
The Tánaiste added that the Government will look at commercial rates and VAT in the Budget.
"The virus doesn't live in restaurants or hotels or office blocks or pubs or restaurants," he said.
"We need to be getting back to basics.
Mr Varadkar added that people should keep their distance and keep washing their hands.
The new rules come in to affect today and will be in place until October 10.
The aim is to reduce the spread of the virus and ease the pressure on the health service.