West Corridor ($508·2m)

This will be the first of the new projects to start. Final design is now underway, and construction will start in 2009 for opening at the end of 2013. The 19·5 km light rail line will link Auraria West station in Denver with Lakewood and the Jefferson County Government Center near Golden, serving 11 stations. It will follow the former Associated Railroad right-of-way between Denver and Lakewood, and then parallel 6th Avenue.

A new bus/rail interchange is envisaged at the existing Lakewood Federal Center park-and-ride. RTD says the important St Anthony's Hospital is planning to relocate to this site, contributing to the anticipated ridership of 37000 per day in 2025.

East Corridor ($702·1m)

Second priority is the 38 km commuter rail route running east from Union Station to Denver International Airport, serving five stations. Due to open by the end of 2014, this will partially follow an existing rail corridor, with a new branch into the airport. RTD chose commuter rail because of the relatively long distance and few intermediate stops. There was pressure to adopt light rail, with more intermediate stations to serve new residential areas - notably where the line passes the site of the former Stapleton Airport which is now being redeveloped - but this was not considered cost-effective. With considerable park-and-ride traffic from Aurora as well as the airport business, the line is predicted to be carrying 35000 passengers per day in 2025.

US36 Corridor ($791·1m)

Also scheduled to open in 2014 is a 61·3 km commuter rail line running northwest from Union Station to Boulder and Longmont, serving seven stations. The Environmental Impact Statement is due to be published next year, with right-of-way selection completed by the end of 2007 and construction starting in 2010.

Commuter rail is the locally-preferred alternative for the longer trips to Boulder and Longmont, but this mode is not well-suited to making frequent stops to serve the rapidly-growing areas along the corridor closer to the city. So RTD is planning to augment the rail service by a 28·9 km bus rapid transit route from 2016. It would build the six bus stations, but is dependent on CDoT to provide the HOV lanes. Estimated daily ridership for 2025 is put at 10000 rail and 17000 BRT passengers.

North Metro Corridor ($428·1m)

Work on the Environmental Impact Statement for this 28·9 km line from Union Station through Commerce City to 160th Street began in the autumn of 2005. With final design to be completed in 2010 and construction starting the following year, the route is expected to open in mid-2015.

Marsella says this belt along the northern part of I-225 is one of the fastest-growing urban areas in the entire USA. The locally-preferred alternative was light rail, but RTD opted for commuter rail, with shared use of existing tracks, which is 30% cheaper. The line will have eight stations, and is expected to carry 12000 passengers per day by 2025.

As part of the North Metro corridor, FasTracks includes provision to reserve a right-of-way for a rail link in the I-76 corridor leading northeast from Commerce City to Thornton and Brighton, where prospects for long-term development and growth were identified during the initial consultation phase.

I-225 Corridor ($442·3m)

The eastern section of the I-225 orbital belt is to be served by a 16·9 km light rail extension from Parker Road through Aurora to an interchange with East Corridor, adding seven stations to the two included on the T-REX branch. A major traffic generator will be the University College Health Services complex at Fitzsimons Campus, near Aurora City Centre. To serve these two locations, with a potential catchment of 50 000 people, the light rail line will diverge briefly from the interstate alignment to run through the heart of the campus. Expected to open towards the end of 2015, the line is conservatively expected to be carrying 18000 passengers per day by 2025.

Gold Line ($463·5m)

Opening at the end of 2015, the 18 km light rail line from Denver to Wheat Ridge and Arvada is intended to follow an existing rail corridor. It will run north from Union Station alongside the Longmont commuter rail line to Pecos and then turn west to parallel the I-70 highway, serving seven stations. Work on the EIS is now underway, with final design scheduled for 2009 and construction to start in 2011. With the population of this corridor expected to grow by more than 30% between now and 2025, the estimated ridership in that year is put at 19000 per day.

Central Corridor ($118·4m)

Not expected to start final design until 2009, but due to open in mid-2015, this project envisages a short 1·3 km extension of RTD's original light rail line from 30th & Downing to an interchange with the East Corridor at 40th & 40th, adding two stations. The package also includes platform lengthening at the 14 existing stations to take four-car trains. With a major development taking shape on the site of a former rubber factory beside I-25 & Broadway, daily ridership on this line is expected to reach 37000 in 2025.

Southeast Corridor ($183m)

Next year will see bids invited for initial planning of a 3·7 km extension of the T-REX line from Lincoln Avenue to Ridge Gate Parkway and new urban developments at Lone Tree, which would be built around 2013-16. Adding three stations, the extension is predicted to boost the Southeast Line ridership to no less than 60000 passengers per day by 2025.

Southwest Corridor ($164·1m)

The final light rail project in the programme is a 4·0 km extension of the Southwest Line from Littleton & Mineral to Highlands Ranch, terminating at the intersection of Lucent Boulevard and C-470, where a 1000-space park-and-ride facility is planned.

Another 440 spaces would be added at Englewood, where demand has already outstripped the current 910-car capacity. Platforms at the existing stations will be expanded to take four-car trains, and an extra station added at Bates near the Elati depot. Due for completion in 2016, these investments are expected to boost the line's ridership from around 20000 per day today to around 25000 in 2025.