BJP frets that an incidental or "mischievous" hurdle on the only surface link between Patna and 17 districts of Bihar can stop thousands of supporters from reaching the rally its prime ministerial nominee Narendra Modi is scheduled to address on October 27.
To deal with such a possibility, the party plans to keep 31 cranes on standby to promptly remove any blockage that might hinder the traffic to the rally venue.
"We have to ensure nothing comes in the way of people coming to Patna for Narendrabhai's October 27 meeting. That's why we have made parallel arrangements", said Bihar BJP president Mangal Pandey.
A major point of threat the party has identified on this score is the 5.57 km long Mahatma Gandhi Setu, effectively Patna's only link to 17 districts of north Bihar across the Ganga.
"One flank of bridge is already closed for repairs. Breakdown of a truck is all it may take to block lakhs of people from north Bihar from entering Patna," said senior BJP leader Nand Kishore Yadav.
As such, he said the party has also decided to deploy over 100 private security men on the bridge to ensure smooth movement of traffic and to guard against any mischief that can disrupt its movement.
Yadav, leader of the opposition in the Bihar assembly and former road construction minister, demanded that bridges bringing rallyists to Patna be made one way on the rally day like it was done for the JD (U)'s adhikar rally in Patna on November 4 last year.
It would be Modi's first rally in Patna after he was appointed as the BJP's prime ministerial candidate. For the state BJP, it is a show of strength in the wake of its split with longtime ally JD(U) that had objected to Modi's candidature.
The demand, he said, also applied to the Koilwar Bridge, which links Patna with south-central Bihar and the Rajendra Bridge at Mokama, also across the Ganga. The latter is under repair and closed to heavy vehicles, at present.
Yadav confirmed emergency handling of any breakdown on the bridge was one of the major tasks assigned to cranes being deployed to facilitate smooth movement of rally-oriented traffic.
Another backup measure the party has planned upon to guard against the blockage of the bridge is to engage a large number of boats to ferry north Bihar rallyists to Patna, across the river.
"Thanks to an organisation of fishermen, we have 126 country boats committed for Sunday's rally. They will bring people of places like Sonepur, Hajipur, Bidupur and Raghopur," Pandey told HT.
Other party leaders said at a time when stakes were high and the atmosphere heavy with suspicion, even 'excessive' measures answered to a rationale.
"Road blockage and traffic jams are always a threat to any mass mobilisation effort. But in these troubled times, posturing counts for as much as do safety measures," said a former state BJP chief.