Both schemes, which have been submitted to Dorset County Council, await full planning permission.
Work at Chapel Gate roundabout, which connects Christchurch Road and Parley Lane, will begin after the summer, changing the roundabout to a signalised junction.
The major project, costing £3.3m, will take seven months to complete, although plans have yet to be finalised.
The proposals include;
• Changing the roundabout to a signalised junction
• Installing toucan crossings
• Adding a new lane on the southern and western carriageways to 'improve capacity'
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Andrew Bradley, Dorset County Council's project engineer, said signalisation of the junction will help to improve the flow of traffic, particularly at peak times, to and from the Aviation Business Park, which is integral to the LEP's proposals.
A lot of the work will be completed away from the main road, but when it comes to joining up with the existing road, traffic is likely to be controlled by temporary signals, avoiding peak hours, Mr Bradley said.
The second major scheme, to move Hurn roundabout, is scheduled to start just over a year later, in October 2017, and will take between six to eight months.
It is estimated to cost £2.4million and includes;
• Moving Hurn roundabout east, to the middle of the field between Hurn Sports and Social Club and Hurn Bridge House
• Installing a new signal controlled toucan crossing for pedestrians and cyclists on the Avon Causeway
• Horse crossing points on Christchurch Road and Parley Lane
• Christchurch Road approach would be re-positioned to meet the new roundabout and the existing road grassed
• Avon Causeway approach also moved
• The junction with Matchams Lane would also be relocated so it meets the new Avon Causeway carriageway
• In total, around 240 trees, including mature oaks and sycamores, would be felled, although considerable replanting and landscaping is planned
• New street lighting would be put in along Parley Lane, Avon Causeway and Christchurch Road which would be in operation through the night
Originally mooted three years ago but shelved for further work, the plans have been revived, and now form a major part of the LEP's Bournemouth International Growth programme.
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LEP director Lorna Carver said: "The status quo is not good enough.
"Part of the reason we have unveiled this scheme in its entirety is so people know we are working towards a greater goal.
"In opening up the work space at Aviation Business Park, it will in turn lead to more traffic, so we want to improve the roads partly to make it more attractive and also in an attempt to ease the current issues.
"We do regret the short term pain this may cause but it will be worth it. We have presented the scheme as a whole, so people can see what we are trying to achieve overall."
A spokesperson for Bournemouth Airport added: "We welcome these works as they form part of a wider package of Dorset LEP schemes which will improve the infrastructure in and around the airport and the business parks."
Cllr Margaret Phipps, Hurn Parish Council chairman, said: "The parish council, while appreciating that there needs to be improvements in access to the airport, feel that work at Blackwater junction should have been done before Hurn roundabout.
"Traffic queues back from Blackwater junction into Hurn and around the roundabout.
"Obviously, Hurn roundabout would have been done eventually, but our thoughts are that Blackwater should have taken priority."
Under the raft of LEP measures announced last week, the development around Bournemouth Airport will also include the release of up to 60 hectares of land at Aviation Business Park and 350 new homes, 50 per cent of them 'affordable'.