PEAK hour traffic between Lami and Nausori is expected to increase by 22 per cent between 2014 and 2030, a survey by the Fiji Roads Authority revealed.
And it will take commuters an additional quarter of the time it takes now to travel between destinations.
The forecast - Greater Suva Transportation Strategy 2015-2030 report - was based on the conservative assumption that buses retain their role as the main mode of transport in the greater Suva area.
FRA chief executive officer Neil Cook said if Fiji followed other developing countries with higher incomes equal higher car ownerships, equalling more cars on the road, congestion would be a problem for roads in and around Suva.
"Population growth plus increased urbanisation equals more cars and more congestion," he said.
The survey, conducted over six months, was done by Predict Consulting, Scope Pacific Limited and GTA Consultants.
The FRA said this would be the blueprint for the greater Suva area (GSA - Suva, Nasinu, Nausori and Lami) over the next 15 years.
"The vision of this strategy is built on how the greater Suva area aspires to have an integrated and sustainable transport system that contributes to an inclusive, prosperous and environmentally responsible region," FRA said.
The report also makes reference to how the current transportation system in this region was influenced by short-term decision making in the past and identified six key issues - traffic congestion, enforcement and regulations, bus infrastructure and routes, quality of transport infrastructure, road safety and driver education and awareness.
"To tackle the issues with the transport network, a list of 137 priority projects were developed for consideration for implementation over the next 15 years spread across the study area and shared among a variety of stakeholders.
"Seven key programs (collection of options) of note are dedicated bus lanes, improved bus terminals, linked traffic signals, improved pedestrian safety, enforcement, intersection upgrades and planning (further planning)."
Mr Cook said if all projects were implemented, the investment would be about $1billion and this would be decided by the government.
"Many of the projects are extensions of what is already being considered in FRA work programs or in other agencies' work programs so not all of this would be new investment."