The outline plan has been submitted to ministers after County Hall announced in July that it wanted to see the 15 councils that currently make up Lancashire's complex local government map scrapped and replaced with three standalone authorities.
The document confirms that the proposed new areas would comprise "Central Lancashire" (based on the footprints of Preston, Chorley, South Ribble and West Lancashire councils), "North West Lancashire" (Blackpool, Fylde, Wyre, Lancaster and Ribble Valley) and "East Pennine Lancashire" (Blackburn with Darwen, Burnley, Rossendale, Hyndburn and Pendle).
It states that the proposed new council areas - each of which would cover a population of around 500,000 people - would be based on "credible geography, economic coherence and commuting patterns".
The move comes after the government announced earlier this year that two-tier areas like Lancashire would have to simplify their local authority set-up if they wanted to strike a devolution deal to receive extra powers and cash from Whitehall .
That would mean the creation of so-called "unitary" authorities - like those already in existence in Blackpool and Blackburn, but larger - and a new combined authority, of which they would form a part, which would be headed by an elected mayor and direct strategic decisions for the whole county on devolved issues like transport and skills.
The changes would, according to the report, enable Lancashire to speak with "one single, credible voice".
County council leader Geoff Driver says that the radical overhaul is "the only game in town" if Lancashire is to get the most of what is on offer from ministers - which could include an extra £30m per year for the county over the next 30 years, based on similar deals.
"It is clear that the government sees combined authorities and elected mayors as the vehicle for 'levelling up' the country as they promised at the general election," County Cllr Driver explained.
"So unless we're prepared to see the people of Lancashire fall further behind - which would be shameful - we've all got to get together and sort this out.
"Some people will knock it and say [the extra funding] is nothing, but when the government gets through Covid, then we will start seeing the real benefits coming to the [newly-created] combined authorities - and we simply won't get them if we aren't part of that."
It emerged earlier this week that Lancashire was not on a list of five areas reported to be at the front of the queue for a devolution deal - but County Cllr Driver said his aim was to "get amongst them".
The document sent to the government claims that ripping up the council map in Lancashire could save between £60m and £80m within three years - half of which would be ongoing savings and the other half one-off windfalls.
County Cllr Driver said that the most telling financial reckoning would be the "cost of not doing it" - but stressed that underlying funding disparities across local government would still have to be addressed in a long-promised government review now due next year.
He also denied that fewer councils covering larger areas would do a disservice to democracy - because of government plans to strengthen the role of parish and town councils.
However, opposition groups at County Hall condemned the content and the timing of the Conservative-run authority's bid for a break-up of the current structure.
Labour's deputy leader John Fillis said there had been "no consultation with other parties, district councils or, most importantly, residents".
"I'm not against reorganisation if it is shown to benefit the people of Lancashire - but this will cost thousands of jobs across local government.
"It would be a recipe for disaster during the current crisis. Would people expect us to be focusing on this issue at the moment or helping our communities?
"There should be a proper discussion at some point in the future - whereas this is just a powerplay by cowardly Conservatives who are running scared of the people," he said, referring to the likely cancellation of next year's county council elections if Lancashire enters into meaningful discussions on devolution in the coming weeks.
Labour group leader Azhar Ali added: "Geoff Driver should be lobbying government for more money to get Lancashire through Covid - ensuring we have a proper test and trace system up and running and supporting our food banks.
"Keeping our elderly cared for and our kids fed is more important than him holding on to power."
County Cllr Driver said his opponents were putting their "heads in the sand" and trying to score political points instead of "thinking of the best interests of the people of Lancashire".
Meanwhile, Liberal Democrat group leader David Whipp said that the "loss of control for local residents that would be brought about by a combined authority and new unitary councils would be an absolute disgrace".
"It would concentrate power into the hands of a single person - and is now really the time to be shuffling the deckchairs on the Titanic when we are living through the biggest crisis since World War Two?" he asked.
The Green Party's Gina Dowding - also speaking on behalf of the independent councillors at County Hall - said that now was not the right time to be discussing the issue, "whatever the rights and wrongs of the model that local Conservatives are trying to push through"
"There are simply far too many important issues that should be the concern of senior managers and councillors. More importantly, the whole so-called 'local devolution agenda' is not about giving more powers, trust and control to local communities - it is about central government pulling the strings."
The plans drew a mixed response from the 12 district and two unitary councils in Lancashire when they were first floated earlier in the summer. Some backed the suggestion, others support reorganisation but along different local lines - while the sweeping council changes and the introduction of an elected mayor proved a stumbling block for some Lancashire leaders.
The document sent to government says that Lancashire will explore the possibility of establishing an independent "democracy commission" to engage with the public and guide the journey towards a new council model in the county.
COUNTY COUNCIL'S CLAIMED BENEFITS OF CHANGE
In their proposal, Lancashire County Council has told the local government secretary Robert Jenrick that the proposed council shake-up will:
***Build on the identity of Lancashire's "unique towns and cities".
***Raise the profile of Lancashire with the government and within the Northern Powerhouse.
***Ensure "housing allocation and delivery are...in the right places".
***Better align environmental priorities and the issues of transport and planning.
***Maintain a "whole-Lancashire" brand.
***Create a "more manageable number" of local stakeholders.