DenverInfill Blog

We left our tour at the Oak Station site. From there, we will travel west to the end of the line at the Jefferson County Government Center Station while passing the new St. Anthony’s Hopsital and Red Rocks Community College.

As I mentioned in the last post, initial construction activities are underway at the Oak Station site. As the guideway manuevers its way through the Lakewood Technological Park, it turns to the south as it approaches Simms Street.  You can see that foundations for the catenary poles are in place and the guideway has been graded already.

The tracks will pass just to the east of the old Kacey Fine Furniture building off of the 6th Avenue frontage road. From there, the tracks will cross the 6th Avenue Bridge – the crown jewel of the West Corridor project. The massive basket-handled tied arch bridge was fully constructed at the manufacturer’s site in Oregon, then dismantled and brought to Denver. It took 34 truck shipments to deliver all the pieces of the bridge. It was then reconstructed just south of 6th Avenue and rolled across the highway on May 1. The bridge was pushed across the highway by two, eight-axled, 35′ hydraulic ram platforms. This was the first time that this type of bridge was rolled out using this method in the U.S.

The bridge has 1.2 million pounds of structural steel and nearly 55,000 high-strength structural bolts. The arches and cables will provide most of the structural support of the bridge. The bridge is 43 feet wide – wide enough for two light rail tracks – and nearly 65 feet high from the top of the arch to the bottom support beam. The weight of the tracks and ballast crossing the bridge is more than that of the structural steel in the bridge itself. The bridge support columns can support 2.7 million pounds and a sustained wind of 100 mph. There are 44 cables on the bridge, each 2 3/8″ in diameter and nearly 1,950 feet long. They have a breaking force of nearly 688,000 pounds – that’s 344 tons! The 6th Avenue Bridge uses “weathering steel” which will rust to a dark purple/brown color and form a protextive oxide coating which eliminates the need for painting now and in the future without threatening any structural integrity (this also saved RTD money). The cables will be lit by white LED lights once the bridge is complete.

The arches lean inward (hence the basket-handle name) so much so that they are 27 feet closer at the top of the bridge than at the track deck. Each arch can withstand nearly 3 million pounds of compressive force and will expand nearly 3.5 inches during extreme temperatures. The arches are supported on their own bearings by the piers on either side of 6th Avenue. There are also expansion joints at each end of the arches to facilitate temperature movements. Oddly, the shape of the arch is derived from a mathematical equation emulating the equation used to describe the force of gravity. Hopefully someone can tell me what that means – I’m a planner, not a mathematician.

Once the trains cross 6th Avenue, they will head onto former Denver Federal Center property and travel south towards the new St. Anthony’s Hospital just west of Union Boulevard at 2nd Street. The new hopsital – which is oddly Lakewood’s first – opens sometime next year. The existing Cold Springs park-n-Ride at 6th and Simms/Union will be relocated next summer to the new Federal Center park-n-Ride just north of 2nd Street across from the hospital. The site today is a vacant lot, but construction should start within the next few months.

The corridor will be single track from the Federal Center Station west to the end-of-line station at the Jefferson County Government Center, but double track from the Federal Center Station into Downtown. The Cold Springs p-n-R needs to moved to make way for a tunnel which will be constructed underneath Union Boulevard. Not much in the way of major construction can occur on the tunnel until the p-n-R moves. However, the corridor’s future path can be seen leading up to the p-n-R.

The corridor will then travel on the south side of 6th Avenue, sandwiched in between the frontage road and the highway. All of the construction work seen when you travel along 6th Avenue is the light rail guideway. The Red Rocks Community College Station has construction activity underway. Crews are forming the foundations for the shelters and the platform. There will be no parking at this station and I haven’t heard any word regarding a connection with the college. It’s a bit of a walk from the station site south to the college – hopefully something will be worked out.

There are a lot of cool machines at work along the corridor. At first glance, this one is pretty awesome - it beats post hole diggers. However, it is the without a doubt, one of the most annoyingly loud machines I have ever heard. It sounds like nails on a chalkboard as it lumbers along the highway.

If the basket-handled bridge at 6th and Simms is the crown jewel of the West Corridor, the Indiana Bridge is arguably a close second. The bridge is made of both concrete and steel and is the longest bridge on the corridor, spanning 1,531 feet. The 11-span bridge uses three independent construction frames – the first and third (those spanning the onramps) use a post-tensioned concrete box girder system while the middle span uses three steel plate girders. The center span over 6th Avenue is the longest single span in the corridor, reaching 270 feet. The tallest columns are over 40 feet high, which allows for future construction of a ramp between 6th Avenue to I-70. Like the 6th Avenue Bridge, the Indiana Bridge uses the same “weathering steel” which will rust to a dark purple/brown color. The Indiana Bridge will also have the rails attached directing to the bridge deck to make its load lighter. The bridge is only 20 feet wide, but trains will travel east and westbound intermittently. The 7.2 million pound bridge took 48,000 cubic feet of concrete and 128,000 feet of steel post-tensioning strand to complete.

The tracks will then head west on the north side of 6th Avenue and travel underneath I-70 in an already excavated tunnel. It’s hard to get a picture of the tunnel without risking life and limb, so we’ll have to settle for this view a little further out.

The trains will then cross over Colfax at 6th Avenue on a 4.6 million pound, 696 foot long, six-span bridge. The bridge has 266,000 pounds of reinforcing steel and 4.3 million pounds of concrete. The bridge will also have the tracks attached directly to the bridge deck to make the span lighter. The bridge was built without approach ramps, but those were added as construction along the corridor moved ahead. The ramp from westbound 6th Avenue to eastbound Colfax will be realigned to interface with the bridge once its complete. The bridge still carries the same design theme we saw earlier along the corridor near Wadsworth and Sheridan. There is also more construction staging occuring on this end of the corridor as well as can be seen with the concrete tie storage underneath the bridge.

The corridor will then travel just south of the Golden Cemetary at 6th and Ulysses before crossing at grade at Johnson Road into the Jefferson County Government Center complex. The tracks will pass through a hill which was located west of Johnson Road. The cut to access to JCGC complex and the future park-n-Ride is shored up by what is known as a “soil mill wall,” which uses a top-down construction method where crews excavate about five feet of soil, place tensioned support strands in the soil, pour concrete over it, then repeat the process over and over until the entire wall is complete. The cut is visible just to the left of the ramp from C-470 in the pictures below. The walls have a texture on them resembling some kind of a rocky surface. There will be a new RTD parking garage constructed just south of the existing parking at the JCGC to handle the end-of-line station. To watch the construction progress at this station, check out http://www.earthcam.com/clients/denverTransit/ for a webcam and still photos of the site.

That’s all for this West Corridor update. We’ll revisit this in the future before the corridor is open in 2013 to see how the corridor has changed. In the mean time, check out www.rtd-fastracks.com for more information on the West Corridor!

We’ll continue our westward trek along the West Corridor light rail line today, traveling from the Sheridan Station west to the Oak Station.

The Sheridan Station will be located below a newly constructed Sheridan Boulevard bridge structure built to span across Lakewood Gulch. The bridge will raise traffic to a level roadway between 10th and 14th Avenues where the road used to take a rather steep dip into and out of the gulch. The bridge - which is about halfway complete – will use more than 370,000 lbs of reinforcing steel and 2,000 cubic yards of concrete. There are also 47 drilled shaft foundations that are driven nearly 40 feet into the ground. The bridge will carry two lanes of through traffic on Sheridan in each direction with 10 foot sidewalks on both sides of the structure. Multiple utilities are also hidden between the girders across the bridge. Interestingly,, the original West Corridor plan called for the configuration being constructed today. However, in 2006-2007 when the West Corridor’s budget was being finalized, a proposal was floated to leave Sheridan Boulevard traffic as it was (with a steep dip in and out of the gulch) and take light rail up and over the vehicular traffic to lower costs. The cost concerns stemmed from construction mitigation which would have required RTD to construct a 4 lane temporary bridge for traffic on Sheridan. However, CDOT has allowed RTD to limit traffic on Sheridan to one lane in either direction while the new structure is being built, thus, saving RTD enough money to proceed with its original plan. Isn’t it amazing how some government coordination works…

RTD also acquired several parcels just north of 10th Avenue  near the station to use as construction staging areas prior to constructing the parking structure. More demolition work is underway right now preparing for construction of the garage.

Additionally, both the City & County of Denver and the City of Lakewood have completed station area plans for the Sheridan Station. For those who don’t know, Sheridan Boulevard is (for the most part) the boundary between the City & County of Denver and Lakewood and Jefferson County. The plans spell out what kind of changes the respective jurisdictions see coming to the area following in the future, which was envisioned following a public participation process. Denver’s plan can be found here and Lakewood’s plan can be found here.

Some of the track segments can be seen near the Sheridan Station. The tracks actually arrive in 80 foot chunks and are flash-welded together to make sections that are 800 feet long for installation along the corridor.

The corridor then rises out of the gulch as it approaches the Lamar Station. The Lamar Station will not provide any parking. The station will be what RTD calls a “Neighborhood Station,” meaning its simply a walk-up station with no parking provided – very similar to the existing Louisiana-Pearl Station on the Southeast Corridor. The station has little in the way of platform construction right now, largely because the area is also being used as a construction staging area.  The Lamar Street Station Area Plan can be found here.

As I mentioned in an earlier blog posting, large sections of sound walls have been erected. The light brown/tan color is the final painted color that will be applied to all of the sound walls along the corridor. There are sections that have been erected but are waiting to be painted.

The Wadsworth Station will sit over Wadsworth Boulevard on a 63 foot wide, 400 foot long, double-track light rail bridge. The 11.1 million pound bridge has nearly one million pounds of reinforcing steel with 10 million pounds of concrete. To make the bridge lighter, the rails will be attached directly to the bridge deck, eliminating the need for ballast and rail ties. The station will sit nearly 30 feet above Wadsworth and include staircase and elevator access on both sides of the street. The City of Lakewood has also provided funding to improve some of the amenities (canopies, benches, etc.) at this station. A 1,000 space parking garage will be constructed just east of Wadsworth between 13th and 14th Avenues. The City of Lakewood envisions the Wadsworth Station as being one of the signature stations along the corridor and have completed a station area plan, which can be found here.

After the trains cross over Wadsworth, they will continue west at 13th Avenue. Sound walls have been installed and are awaiting their coat of brown paint.

The Garrison Station hasn’t seen much in terms of platform construction yet – but it’s coming. The station is another neighborhood station – no parking will be provided. The Garrison Street Station Area Plan can be found here.

The trains will cross over Kipling Street on a single span, double track bridge – the first bridge built along the corridor. A bike/pedestrian path paid for by the City of Lakewood will be separated from the trains and the station platform by a fence on the north side of the structure. The bridge has more than 100,000 pounds of reinforcing steel and 3 million pounds of concrete – and as with the Wadsworth bridge, the tracks are attached directly to the bridge deck to lighten the load across Kipling. Sound walls will also be installed along the approaches on either side of the bridge. The 3.1 million pound, 120 foot long bridge will sit 30 feet over Kipling.

After the trains cross Kipling, the alignment curves slightly to the north where different examples of sound remediation efforts are visible. Homeowners along the alignment who qualified for soundwall installation could choose between the concrete soundwalls, a cash opt-out, or alternative treatments (being the retaining block wall). A contrast between the two is visible in the picture below.

Many roads throughout this segment of the corridor have been permanently closed to minimize the number of at-grade crossings that the light rail must make and to allow for necessary grade changes.

The Oak Station has some visible construction progress. The initial construction activities have started at the platform site and land to the north (which will become the new 200 space park-n-Ride) is being used for construction staging. The Oak Street Station Area Plan can be found here.

So that’s it for this West Corridor update. Next week, we’ll take a look at the most visible construction activities along the corridor and some BIG bridges.

RTD and its local and regional partners celebrated the West Corridor’s halfway point this morning in a ceremony at Paco Sanchez Park. Attached here is RTD’s Press Release regarding the event. Only about two and a half more years until we can ride the train all the way west to the Jefferson County Courthouse!

Some quick West Corridor construction facts to tide us over until the next construction update later this week:

• RTD signed a Notice to Proceed (NTP) on Jun. 16, 2009, partnering with Denver Transit Construction Group (DTCG).
• Crews have been at work along the corridor for nearly two and half years. Pre-construction activities (such as utility work) kicked off in April 2008.
• Construction along the corridor is expected to be complete in January 2013 (a year ahead of the original schedule) with the corridor opening for revenue service in May 2013.
• 15 bridges, flyovers, and tunnels are either complete or currently under construction with the three planned pedestrian bridges already complete.
• Construction has begun on all 12 stations. Elevator shaft work has started at both the Wadsworth and Red Rocks Community College stations.
• Current construction progress includes:
  • Right-of-Way (ROW) purchases are nearly 90% complete.
  • All light rail vehicles are ready for opening-day service.
  • Dry utility (power, cable, etc.) relocations are 78% complete.
  • Sound walls are 50% complete.
  • Drainage at the main drainage structures (mostly within Lakewood Gulch) is 75% complete.