Last year metro Atlanta officials were brimming with optimism about the prospects of tackling the region's traffic problems.

New toll lanes opened to public acclaim. Other major road projects were underway. And state legislation laid the groundwork for a dramatic transit expansion across the region.

But 2019 proved to be the year that optimism faltered as road projects and transit expansion alike were delayed or put on hold. Here’s a look at the top transportation stories of the year:

MARTA bombs in Gwinnett County … again. Buoyed by momentum carried over from 2018, this year began with a swoon of optimism about the future of transit in metro Atlanta.

In January, MARTA CEO Jeffrey Parker called for a $100 billion transit "moonshot" — a colossal investment on a scale unimaginable just a few years earlier. State lawmakers talked about bringing transit expansion to rural Georgia to aid homebound seniors, needy students and workers without cars. MARTA made Atlanta look good during the Super Bowl. And after decades of resistance and failed votes, Gwinnett officials were pushing to join MARTA — a move that could pressure Cobb County and perhaps others to follow suit.

It didn't work out that way. Gwinnett voters rejected MARTA for the third time since 1971. Transit supporters blamed the county's decision (under pressure from state lawmakers) to hold the vote in March instead of November 2018. Metro Atlanta officials downplayed the defeat. And Gwinnett officials have indicated they'll try another referendum as soon as next year.

But nothing did more to stall mass transit’s momentum than another defeat in Georgia’s second-largest county.

Major road projects delayed. Since then-Gov. Nathan Deal announced a 10-year, $10 billion road building plan in 2016, Georgia has been preparing for a massive highway construction binge. Among other things, the plan calls for toll lanes on the top half of the Perimeter and Ga. 400 and new I-285 interchanges at I-20 east and west of Atlanta.

But the toll lanes on Ga. 400 and the top end of the Perimeter caught flak from residents worried about the effects on their neighborhoods. And local governments sought changes to minimize the impact.

Then in October, the Georgia Department of Transportation announced it was delaying several projects while accelerating the timeline for others elsewhere in the state.

The Ga. 400 toll lanes, originally set to be completed in 2024, were pushed back to 2027. The express lanes at the top end of the Perimeter, originally set to open in 2028, were broken into two projects and pushed back until 2029 and 2032. The new I-20 interchanges were also pushed back several years.

GDOT cited various reasons for the delays, including the need to break up the top end of the Perimeter's lanes into smaller projects to encourage more contractors to bid on the work. The bottom line, though: Traffic relief for many commuters will be delayed for years.

More transit setbacks. The failed Gwinnett referendum wasn't the only setback for transit. The delay in construction of toll lanes on Ga. 400 and I-285 led Fulton County to push back its timeline for transit expansion.

The county's plans call for bus rapid transit lines in toll lines along both those highways. Fulton officials had discussed asking voters to approve a 30-year, $1.2 billion transit sales tax measure next year. Now it may be pushed back to 2021.

Meanwhile, efforts to encourage transit expansion in small cities and rural areas of Georgia stalled in the General Assembly. Legislation that would have created a new agency to oversee transit expansion passed the state House of Representatives but died in the Senate. Its sponsor is hopeful it can be revived in the upcoming legislative session.

Transit signs of life. The news wasn't all bad for transit supporters. Two agencies advanced plans for transit expansion this year.

First, MARTA approved a timeline for its $2.7 billion Atlanta expansion. The timeline puts some new bus rapid transit lines on the fast track while pushing back more expensive rail projects. One of those projects — the Capitol Avenue/Summerhill line — would be the region's first bus rapid transit line, set to open in 2024.

Fans of the Atlanta Beltline were not happywith the timeline. Under MARTA's plan, the first Beltine segment wouldn't be completed until 2028. Supporters want the first segment completed within three years, with much of the rest done by 2030. MARTA officials say they understand those concerns — and see them as evidence of tremendous support for transit in Atlanta.

Meanwhile, a new state agency — the Atlanta-Region Transit Link Authority — drafted a transit plan for 13 metro counties. The initial plan is a laundry list of projects submitted by local governments, and the ATL board did little to pare it down. But over time the plan will help prioritize projects for crucial federal funding and could prepare the way for long-sought state funding of transit construction.

Work on major interchange continues. Finally, work continues on a pivotal project for both highways and transit — the $800 million reconstruction of the I-285 interchange at Ga. 400.

The interchange was designed to accommodate 100,000 vehicles a day, but it now handles about 420,000 each day. Predictably, the result is usually a traffic mess any time of day.

State officials broke ground on a new interchange three years ago. It's the linchpin of GDOT's plans for a 120-mile network of metro Atlanta toll lanes. And that means it's also crucial for bus rapid transit lines that could operate in those lanes.

This year GDOT expanded the scope of the project to add two new I-285 bridges — over Glenridge Drive and Peachtree-Dunwoody Road. That will add six months to the construction timeline. The work will continue through the end of next year.

Look for more developments on each of these stories in 2020. Like road construction, the quest to address metro Atlanta’s traffic mess never ends.