Dog walkers who leave home without "poop bags" could face fines of up to £100 - regardless of whether their pet fouls or not.
Daventry District Council in Northamptonshire said owners should have to prove how they would clean up after their dogs to cut down on the problem of fouling.
Those who fail to pay the £100 fine under the new powers - which will be introduced on December 1 - could face a penalty of up to £1,000 if the case is taken to court.
The authority said the idea of forcing dog owners to carry plastic bags was not "unreasonable" and the fines under the Public Space Protection Order would not be levied until the turn of the year.
Mike Warren, the council's health and housing official, said: "This order will give us greater powers to take effective action against the minority of dog owners who do not pick up after their pets.
"We will be advising them to make sure they have extra poop bags with them at all times to ensure they have the means to pick up, regardless of how long they've been out and about with their pet.
"It's not unreasonable though, for example, to expect someone who has just arrived at a venue to walk their dog to be carrying poop bags."
A council report said: "It was difficult to catch people who had not picked up their dog's faeces and that was why the proposals had been made to enhance the dog control powers."