RTDʼs FasTracks Program In High Gear RTDʼs FasTracks

Tr a n s p o r t a t i o n
Volume 6, Issue 6 – 2010
RTDʼs FasTracks Program
In High Gear
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Transportation Options
RTDʼs FasTracks A Proactive Plan
Balancing Transit Needs With Regional Growth
ublic transportation benefits
every local traveler, even those
that never once use the service. While public transportation is a
necessity for a small but important
segment of the population, enough
other people see it as at least a viable
option that regularly makes sense
for them. Increasing transportation
options to more people spreads peak
travel volumes over multiple modes,
reducing automobile traffic congestion, an inevitable byproduct of
population growth, and its resulting
consequences.
In 1969, the Colorado General
Assembly created the Regional
Transportation District to plan and
build a public transportation system
for the Denver metropolitan area.
By the end of 1972, the new District
had completed comprehensive initial
studies and issued its legislationmandated transportation plan. Eight
months later, citizens voted overwhelmingly in favor of the plan, which
proposed a regional sales tax levy to
finance development of an integrated
public transportation system for the
region.
Today, RTDʼs range of authority
constitutes an over 2400-sq.-mile
service area that includes Denver,
Boulder, Broomfield and Jefferson
Colorado Public Works Journal July 2010
counties and parts of Adams, Arapahoe, Douglas and Weld counties.
Over its 40 years, the public agency
has refined its original vision for
rapid transit development by constantly studying changes in the region's land use, growth of population
and locations of employment centers. RTD is currently five years into
FasTracks, its multi-billion dollar,
voter-approved program to expand
rail and bus service throughout the
District. The FasTracks rapid transit
expansion program will build 122
miles of commuter rail and light rail
(creating six new transit corridors and
extending three existing corridors),
18 miles of bus rapid transit service
and 31 park-n-Rides creating 21,000
new parking spaces; redevelop Denver Union Station; and redirect bus
service to better connect the eightcounty District. The FasTracks investment initiative is projected to create
more than 10,000 constructionrelated jobs during the height of
construction, and will pump billions
of dollars into the regional economy.
In 1994, RTD opened the I-25
Downtown Express HOV lanes to
buses and also inaugurated light rail
transit with the 5.3-mile-long Central
Corridor line. No tax increase nor
Federal contribution was needed to
build the first LRT line; it was funded
entirely by RTD through an existing
use tax, newly-issued bonds and the
Districtʼs capital reserve. When it
opened, the new LRT system eliminated over 400 bus trips per day
from downtown streets, improving
customer service while reducing
downtown congestion, air pollution
and loads on streets. Even more importantly, however, the two projects
established RTDʼs commitment to
Used with Permission
rapid transit.
In 1980, national studies revealed
that public transit ridership was up
slightly after bottoming out in the
early 1970s, yet transit options were
still not in sync with demand as public transit was serving no more than
12 percent of commuter trips. This
percentage would have to multiply
significantly before any practical
benefits could be realized from providing public transit, and the way to
do that was to improve the efficiency
of existing mass transit systems,
such as adding bus lanes, while also
accommodating and encouraging
alternative transportation modes.
Clearly, increased usage would have
to result to justify any and all investment in rapid transit.
LRT has done just that. RTD currently has 150 LRT vehicles running
five different “lines” and serving 36
stations over 35 miles of track. Each
line was constructed ahead of
schedule and under budget, the
most recent being the 19-mile-long
Southeast Corridor in November
2006. Each has also exceeded ridership projections, with total weekday
LRT system boardings averaging
around 68,000. The comprehensive
FasTracks program will spread that
success to every major corridor in
RTDʼs service area.
“RTD developed FasTracks in
response to the regionʼs recognition
of the importance of passenger rail
in helping address mobility needs,
traffic concerns, smart growth and
ʻgreenʼ transit options in the Denver
metro area,” explains Pauletta Tonilas,
RTDʼs public information officer for
FasTracks. “The initiative was strongly
supported, and now we are building
as much as we can as fast as we can
until the vision is reality.”
What has helped make LRT
successful, and what promises to
help continue that trend in Denver,
is creating new, vibrant communities
all along the corridor in proximity to
each LRT station. Transit-oriented
development has created new centers of community and renewed existing urban areas for the better. TOD
helps “sell” the project to neighboring
communities while obviously compounding the need for coordination
and cooperation between agencies.
The first corridor to be addressed
under FasTracks is West Corridor,
which will eventually travel 12.1 miles
from Denver Union Station to a relocated Auraria West Station, across
I-25 and South Platte River, then
along the existing Associated Railroad right-of-way through residential
neighborhoods along 13th Avenue
in Lakewood. Just east of Simms
Avenue, the LRT line crosses 6th
Avenue and onto Denver Federal
Center, then heads west along the
south side of 6th to Indiana Street,
where it crosses 6th again before
running under I-70 and over West
Colfax Avenue to Jefferson County
Government Center. In June last year,
Denver Transit Construction Group,
a joint venture between Herzog Contracting Corp. of St. Joseph, Missouri, and Stacy and Witbeck Inc. of
Alameda, California, was issued full
Notice to Proceed with construction
Bridge over 6th Avenue is constructed with no piers in
CDOT right-of-way. The bridge was assembled on the
job site and rolled into position in just 14 hours.
Leading the RTD West Corridor project are, from left, John West, DTCG Project Manager; Rick Clarke, RTD Assistant
General Manager of Capital Programs; Lloyd Lovell, DTCG DBE Manager; Phil Washington, RTD General Manager; Jim
Starling, West Corridor Project Manager; and Al Eastwood, West Corridor Deputy Project Manager.
after RTD received a $308 million
Full Funding Grant Agreement from
Federal Transit Administration for the
$707 million line. Planned to open
in 2013, West Corridor will connect
the west suburbs to Denver Union
Station and will include 12 stations
and six new park-n-Rides with 5605
parking spaces.
“We actually broke ground for
the first time on FasTracks in May
2007,” Tonilas continues, “with the
removal of the old trolley tracks
along 13th Avenue and relocation of
utilities along the West Corridor line.
Light rail-related construction began
in spring 2008 with construction of
the bridge that will carry light rail,
pedestrian and bicycle traffic over
Kipling Street.”
The past yearʼs efforts have
focused on construction over and
under the ground, with bridges and
drainage taking center stage, while
next year, crews will begin station
and system construction and placement of track.
Last November, with West Corridor well underway, RTD celebrated
another major milestone for the
FasTracks program with issuance of
FTAʼs Record of Decision signifying
formal Federal environmental approval for the East Corridor and Gold
Line projects. The two projects are
consolidated into the Eagle P3 Project, RTDʼs public-private partnership to deliver portions of FasTracks
projects. Just last month, RTDʼs
Board of Directors selected Denver
Transit Partners, the contracting
partnership between Texas-based
Fluor Corporation and Australiabased Macquarie Capital Group Ltd.
with team members including Ames
Construction Inc. and HDR Inc., to
finance, design and build the estimated $2.4 billion Eagle P3 project,
then to operate and maintain it for
28 years. The Board solicited proposals from three teams pre-qualified
in 2008, but received just two. Construction-related activity is expected
to begin on the East Corridor, a
22.8-mile electric commuter rail line
that will run from Denver International Airport to Union Station, later
this year. The Gold Line is an 11.2mile line, also commuter rail, that
will run from Union Station to Wheat
Ridge, passing through northwest
Denver, Adams County and Arvada.
"This milestone speaks volumes
to the progress we are seeing on
the FasTracks investment initiative,”
said RTD General Manager Phil
Washington at a special ceremony
at DIA. “This is a great vote of confidence by the Federal Transit Administration that keeps us on track
to pursue up to $1 billion in Federal
funds for FasTracks.”
Denver Transit Partners, the “concessionaire” for the public-private
partnership, is just one of a growing
number of private consortiums responding to public needs in a way
that allows communities to benefit
from upfront private equity against
future revenues to help build major
infrastructure projects. DTPʼs proposal added to RTDʼs expected
project costs (utility relocations, for
example) totals $2.085 billion, $300
million lower than RTDʼs budget
estimate. DTPʼs proposal also plans
to open the East Corridor line to DIA
by January 2016, 11 months ahead
of RTDʼs deadline. The Districtʼs
“best-value” evaluation rated DTPʼs
proposal both the higher technical
and lower cost proposal of the two
bidding teams.
While P3 projects have been
more common internationally, RTDʼs
Eagle P3 project takes public-private
partnerships to a broader level, representing a unique model for a major
transit project in the United States.
In addition to final design and construction, DTP is bringing private
financing to the table and, under a
concession contract, will also operate and maintain the rail service on
these lines for 28 years. In return,
RTD will make annual payments to
DTP based on its performance in
meeting RTDʼs service standards.
Through this arrangement, called
Design-Build-Finance-OperateMaintain, RTD reduces its need for
upfront cash.
RTD also expects the Eagle P3
project to attract $1 billion next year
through FTAʼs Full Funding Grant
Agreement process. Of course,
funding is always a serious factor in
the timetable for completion of any
phased infrastructure project. Current economic conditions have left
government agencies everywhere
facing budget cuts to offset lowerthan-expected sales tax receipts.
Success of the Eagle P3 project is
likely to lead to other opportunities
to seek public-private partnership
solutions to keep the overall program
on schedule and serving customers
as soon as possible.
RTD is currently finalizing its
FasTracks implementation plan, with
the objective of having six of 11
construction projects started and
the balance of projects construction
ready by end of 2012. The challenge
is formidable, as below average tax
receipts have left the District facing
budgetary gaps in its base operating
Bridge over Consolidated Main Line
railroad tracks east of I-25 will turn
West Corridor LRT north into the
relocated Auraria West Station. The
bridgeʼs curvature dictated its design
with weathering steel girders.
system as well as in the ongoing
FasTracks program, though the two
are separate issues. In April, RTDʼs
Board voted to postpone pursuing
another increase the current sales
tax until at least next year. If the tax
increase fails to be implemented and
no other new revenue streams are
tapped, full build-out FasTracks plan
is likely to not take place until 2042.
“We are constantly analyzing
financial plans to determine how
we can best spend available funds,”
concludes Tonilas. “We will be making
recommendations accordingly over
the next several years and working
jointly with stakeholders to stay on
track in our mission to bring rapid
transit options to all of the Denver
metro area.” G
As West Corridor architecture and planning manager, IBI Group provided basic design for the corridorʼs 12 stations. Shown
here is the artistʼs rendering of the end-of-the-line station at Jefferson County Government Center. The structure is integrated
into the existing hillside with a tunnel for the LRT trains. Architectural precast and a vegetated screen are used for the exterior
of the parking structure, which is designed for 820 parking spaces on three levels. IBI Group is working on FasTracksʼ next
project, Eagle P3, which involves designing four LRT stations as a subcontractor HDR Inc. and Denver Transit Partners.
CM/GC Contracting Guarantees Maximum Price, Encourages VE
W
est Corridor, the $707 million
capital improvement project to
extend light rail service to Golden,
is the first of six new lines to be
constructed under RTDʼs voterapproved FasTracks initiative. RTD
determined the best method to
deliver this project was through a
CM/GC, or Construction Manager/
General Contractor, contracting
approach.
CM/GC involves bringing a contractor in early in the design process
to provide input, offer cost-saving
suggestions and develop cost estimates. After the design is finalized,
the owner and contractor negotiate
a guaranteed maximum price, which,
once reached, places the risk of
completing the project solely on the
contractor. CM/GC contracts require
buy-in of the design firm, which
typically works under a separate
contract.
The original FasTracks schedule
was developed assuming DesignBid-Build delivery for all corridors.
This provided the most conservative
schedule and still allowed for future
analysis of delivery methods. After
a workshop in 2005, the preferred
method of delivery was largely
changed to CM/GC in an attempt
bring contractors on-board earlier in
the process while still affording RTD
control over final design.
For West Corridor, qualified firms
were contacted before the projectʼs
design was finalized and asked to
bid an approximate price and fixed
fee rate to complete the scope of work.
Price was important, of course, but
not necessarily the deciding factor.
Once determined, the successful
CM/GC was contracted for preconstruction services and immediately
brought its expertise and specific
ideas to the project team, providing
input on final design, cost estimating,
scheduling and anywhere else
beneficial.
The CM/GC then was given sole
opportunity to submit a proposal for
the contract for actual construction,
and was required to submit a guaranteed maximum price. RTD reserved
the right to award the contact to
another if the parties were unable to
reach agreement on the GMP.
RTD released an RFP for its
West Corridor CM/GC in January
2006 and received proposals from
four joint venture teams in April 2006.
In June, RTDʼs BoD concurred with
staffʼs recommendation to select
Denver Transit Construction Group,
a joint venture of Herzog Contracting
Corporation of St. Joseph, Missouri,
and Stacy & Witbeck Inc. of Alameda,
California, and approved the CM/GC
preconstruction contract last year.
DTCG and RTD agreed on a GMP
Mechanically-stabilized earth walls consist of fitted precast concrete panels with
steel straps that extend into the backfill behind the wall. MSE walls are being constructed on the West Corridor LRT project for bridge approach ramps (as shown
here) as well as for retaining earth along the trackʼs route.
of $343 million to build the major
portion of the system, including the
tracks, bridges, stations, crossings,
drainage and grading. The GMP
includes an inflation hedge in case
of cost escalation, but DTCGʼs only
recourse for change orders is due
to scope changes.
CM/GC relationships encourage
value engineering through compilation of minds. In December 2006, a
team of nine technical experts from
around the country came to Denver
to participate in a week-long intensive
review of the West Corridor project.
This VE process is used on may
large projects throughout the country
and is an FTA requirement for all
projects applying for Federal funding,
with the goal to recommend more
efficient and cost effective methods to
build the project. The VE team identified 83 potential VE items and 41
were recommended for acceptance.
One VE proposal offers those
property owners along the alignment
who have a noise impact to opt out
of having a concrete noise barrier
constructed for a dollar amount that
will allow them to handle their own
noise mitigation. Another proposal
changed the plan from building two
tracks between Denver Federal Center and Jefferson County Government Center to just one. Trains are
scheduled to run every 15 minutes in
each direction and the single track
won't affect this timing because
there will still be two tracks at the
stations where trains can pass each
other. The savings from this item
not only comes from less track and
electrical wires overhead, but from
being able to build the bridge structure over 6th Avenue and the tunnel
under I-70 at reduced costs.
DTCG is a diverse and experienced team led by two nationallyqualified firms with a history of construction performance in delivering
urban light rail projects. Herzog Construction and Stacy & Witbeck have
completed many successful projects
through the CM/GC delivery method,
including construction of the first
phase of Utah Transit Authorityʼs
TRAX commuter rail line that runs
from north of Ogden to downtown
Salt Lake City. The joint ventureʼs expertise has secured its ranking as a
national leader in transit and railroad
construction and its combined portfolio of over 150 similar rail transit projects confirmed its selection by RTD.
With a recognized commitment
to partnership building and value
engineering, DTCG selected several
Colorado firms to provide services as
team members. Among these firms
are nationally-recognized Edward
Kraemer & Sons, Inc. and Lawrence
Construction Company, as well as
a range of DBE companies such as
Jackson Construction Company,
Meza Construction Company, Alcam
Metal Distributors Inc., L.F.L. International and Doss Technical Services.
The joint venture team is responsible
for building 13 LRT or vehicular bridge
structures, two light rail tunnels, one
pedestrian tunnel, three pedestrian
bridges, 21 at-grade crossings, three
parking facilities and twelve stations.
By the end of construction in 2012,
DTCG crews will have installed more
than 115 retaining walls, 67 ballast
walls and 10,000 lineal feet of sound
barrier walls, along with significant
replacement, relocation, adjustment
and protection in place of existing
public and private utilities.
With an aggressive 18 percent
goal of DBE participation during
construction of West Corridor, DTCG
is committed to empowering small
businesses for future opportunities
on FasTracks projects. The JVʼs creation of a DBE Trucking Consortium
currently includes 33 local Disadvantaged Business Enterprises.
“The trucking consortium affords
local companies the opportunity to
participate on the largest infrastructure project currently being built in the
Denver metro area,” says DTCG
Project Manager John West. “Qualified DBE trucking companies are
put into a random selection process
through which each is given equal
opportunity to haul for the project.
Through this process, small companies with one truck have the same
opportunity as companies with multiple trucks. Streamlined processes
make this a unique opportunity for
small businesses to be part of
construction and to increase their
capacity for future projects.”
To date, DTCG has added over
$150 million to the local economy
through wages, utilization of local
subcontractors and purchasing of
equipment and materials. The JVʼs
coordination with eight major stakeholders necessitates significant interface with the community at large, and
DTCG actively coordinates with community organizations to ensure local
businesses are provided an opportunity to contribute to the project.
“With a commitment to quality,
excellence and safe working environments, the joint venture is setting a
high standard for future RTD FasTracks corridors,” concludes West. G
West Corridor LRT Design Challenged By Multitude Of Stakeholders
R
TDʼs West Corridor light rail project, the first to go to final design
under the transit authorityʼs FasTracks
program to expand mass transportation options, parallels West 6th
Avenue, which currently carries metro
Denver traffic volumes second only to
Interstate 25. Studies have estimated
the avenue, which also serves as
US Highway 6, will be subject to a 20
percent increase in volume by 2025
as the metro area is expected to
add 1 million new residents. Though
widening the highway was never a
viable option, RTD evaluated a wide
range of transportation solutions for
the corridor in its 1997 West Corridor
Major Investment Study. The MIS
identified light rail along the Associated Railroad right-of-way, most of
which RTD has owned since 1995,
as the Locally Preferred Alternative,
which was then adopted by RTDʼs
Board and incorporated into DRCOGʼs
regional transportation plan.
In August 2001, notice of intent to
prepare an EIS for the West Corridor
project was issued. Scoping meetings were held in conjunction with the
process to identify issues in need of
study, with 43 local, regional, State
and Federal agencies invited to participate and given through October to
submit written comments. In March
2003, RTD and Federal Transit
Administration released the West
Corridor Draft Environmental Impact
Statement, which reaffirmed the
preferred alternative, for public review and comment. All comments
received during the public comment
period were evaluated and responded
to in the Final EIS, which was submitted to FTA in late 2003. A Record
of Decision was issued by FTA in April
2004 to complete the EIS process
and later that year, voters approved
a .4 percent increase in the RTD
sales tax to fund FasTracks, which
went into effect in January 2005.
David Evans and Associates Inc.
is leading a team of over 20 subconsultants to provide transit and
civil engineering, bridge and tunnel
design, and architectural and landscape architectural services for the
project. Conceptual design of the
12.1-mile LRT line between Denver
and Golden and its 12 stations identified ROW conflicts, or the potential
of, but left resolution to final design.
Dozens of meetings were required
to document each stakeholderʼs
specific concerns all along the preferred alternative route. A holistic
approach was then taken to finalize
the overall design, keeping in mind
that agreements would establish
precedents that very likely would
somehow come into play later – on
this and future RTD projects.
Final design challenges were
further compounded due to the economic downturn, i.e., recession, that
resulted in commodities prices inflating considerably beyond those
projected in the EIS. DEAʼs project
team looked closely at hundreds of
line items for areas where “betterments” could be eliminated, at least
for now, without negatively affecting
function. They then were responsible
for again getting everyone on board
with the plan.
“Trust can unravel when you
start trying to change agreements,”
explains DEAʼs Bridge Discipline
Leader and Vice President, Kip
Coulter, PE. “Everyone understood
about construction commodities
prices going through the roof just
before the project bid and that there
were going to have to be concessions
to get the project built, but everyone
has constituents to answer to.
Changes we asked for did not compromise function.”
If conflict could be avoided
through design, that was certainly
considered. A perfect example of
that is with respect to CDOTʼs plans
to improve US 6 over the next 50
years. West Corridor was designed
to be built and operated with no impedance to any CDOT traffic or possible future infrastructure improvements. DEA designed the rail lineʼs
signature bridge to span the entire
width of CDOTʼs ROW. The structureʼs tied-arch design employed here
is both attractive and economical.
Wadsworth Station is the centerpiece of major redevelopment undertaken by City of Lakewood and is the
foremost example of transit oriented
development along West Corridor.
Lakewood began serious planning in
2005 for four West Corridor stations
planned within the City after voters
approved the FasTracks program
West Corridor passes over Wadsworth Boulevard, above, and Wadsworth Station will be located on the elevated structure.
To cross I-70, caissons were drilled and poured from the highway, then capped with precast girders to which precast deck
panels were placed. Highway pavement was then reconstructed while crews excavated the tunnel below.
West Corridor is 12.1 miles long with 12 stations. Track alignment results in 44 locations where light rail crosses an existing
street, 13 of which involve construction of new bridges while two involve tunnel excavation. Some streets will be closed and
the 21 at-grade intersections will all have gates.
Perry Palmer, Jennifer Wood and Stacy Tschuor are part of David Evans and
Associates West Corridor project team.
tax levy. The LRT bridge crossing
Wadsworth Boulevard is an elevated
platform structure that includes the
LRT station. The Cityʼs overall vision
is to transform the area below the
station into a mixed-use, pedestrianfriendly urban village that is also a
lively commercial, employment and
residential district. Multi-story office
and residential buildings with ground
floor retail will be located nearest the
station, while less dense residential
will blend into existing residential
neighborhoods on the redevelopment
areaʼs perimeter. An estimated 5000
people live, and half as many work,
within a half-mile of the station.
Aesthetics are naturally important
to facilitate TOD. As part of the DEA
design team, IBI Group provided
architecture and planning management along with station design,
station area planning, urban design,
planning, TOD coordination and
approvals. Open houses were conducted by the team to undertake outreach involvement in the community
utilizing design charettes and workshops over a two year period. Two
station architectural themes were
developed in the charettes recognizing craftsman-period housing in
each community in the corridor as
were elements of the historic 'radial
line' rail car that formerly ran through
the corridor in the early 20th century.
“We inherited the preliminary design and were charged with taking
it forward,” explains Peter Zurawel,
IBI Groupʼs Denver office director.
“The public outreach sessions transitioned from mere get togethers to
full city-wide open houses as citizens
realized the project was really going
to be built.”
IBI Group has extensive in-house
expertise in transit station design,
and was able to use data from RTDʼs
Southeast Corridor project to guide
West Corridorʼs station designs.
Plans were measured against objectives as well as Federal design
standards before being integrated
into fully-functioning station designs,
which were then discussed with the
CM/GC to verify constructability and
cost containment and pursue value
engineering opportunities. IBI Group
also developed contract documents
and specifications, designed a “wayfinding” signage and corridor aesthetics program, performed stakeholder liaison and approvals and
safety and security certification coordination.
By 2030, West Corridor average
workday ridership is expected to be
nearly 30,000, with five-minute service intervals between Auraria and
Denver Federal Center during peak
hours. West Corridor construction
progress has been impressive, with
teams working together to get the
new light rail service in operation as
quickly as safely possible. Heavy
construction employment has not
suffered as badly from the nationʼs
continuing economic doldrums in
Colorado as it has in many other
states, fortunately. Just ask those
planning and building FasTracks. G
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Bridges Designed To Function Yet Respect Neighborhood Character
I
n its most basic form, a bridge is a
grade-separation structure that
allows movement without cross-interference. In that respect, a bridge is
a bridge is a bridge. In reality, every
bridge should be a constructible
solution that incorporates and balances the needs of all stakeholders
while lending character to its surroundings.
“Transit-oriented development
puts an even greater importance on
designing character into bridges,”
explains Kip Coulter, PE, vice president with David Evans and Associates Inc. and leader of the civil
engineering firmʼs Bridge Discipline.
“RTDʼs West Corridor project aligns
light rail tracks through existing
neighborhoods, presenting an opportunity to revitalize these areas
into dynamic, modern urban environments whose residents benefit
regularly from the convenience of
environmentally-friendly light rail
transit. Elements of the projectʼs
overall design, such as bridges and
stations, can assume a central, primary role in reinforcing the positive
character of each neighborhood.”
The new LRT projectʼs conceptual design necessitated 15 gradeseparated crossings. As final designer
and prime consultant, David Evans
and Associatesʼ first task was to incorporate detail into each crossing
structure design to allow cost estimates to be determined. Bridges
were determined to be the best
solution for 13 of the 15 crossings
(the other two are tunnels), with LRT
traveling over streets, water or railroad tracks at 11 bridge locations
and under a new roadway bridge
at two locations. The DEA design
team considered functional bridge
types against impacts, costs and
overall aesthetics to prepare a type
selection report.
“The preliminary estimate includes our assessment of how a
structure should function in light of
site-specific constraints and parameters such as cost and appearance,”
says Darin Freeman, PE, a DEA
bridge engineer working on West
Corridor. “The type selection report
documents the thought process used
in evaluating each bridge structure
and in justifying the choice incorporated into the preliminary estimate.
The owner and stakeholders review
the preliminary estimate and comment before any design is finalized.”
Span lengths, structural capacity
and caisson placement are typical
constraints, but so are alignment
geometry, construction sequencing
and maintenance requirements. With
functionality given, reaching design
agreement between owner and
stakeholder depends on concurrence
of which parameters are the most
applicable and have the greatest
influence on a structureʼs legacy.
To finalize design of each bridge
in timely fashion, DEA brought in
local partners to help with six of the
13 bridges. HDR Inc., Felsburg Holt
& Ullevig and Hartwig & Associates
Indiana Street bridge, foreground, and 6th Avenue bridge, background, are two of
13 bridges on West Corridor.
Dollies roll 6th Ave. bridge into place,
powered by two 15-ton hydraulic jacks.
Inc. were responsible for taking the
design of certain bridges from 65 to
100 percent.
West Corridorʼs marquee bridge
is the 286-ft.-long steel structure
that crosses 6th Avenue just east of
Simms Street, which will carry two
sets of tracks into and out of a station on the western edge of Denver
Federal Center. The tied-arch design,
in which the majority of the bridgeʼs
structural support is provided through
cables and arches rather than a
foundation, was important because
CDOT safety considerations wouldnʼt permit a center pier in the middle
of 6th Avenue.
“We felt it best to show no impedance on CDOT right-of-way any-
Tied-arch bridge design features arches
that angle inward, from 43 feet wide at
the bottom to 16 feet wide at the top.
where,” Coulter, an expert in arch
bridge design, points out. “CDOTʼs
6th Avenue corridor is restricted as
it is and we didnʼt want to jeopardize
any future roadway improvements
with light rail infrastructure. A tiedarch design eliminates the need for
piers in CDOTʼs right-of-way. Plus,
a tied-arch bridge structure could
be prefabricated in sections, then
assembled onsite and set into place
in only 30 to 40 hours, avoiding months
of 6th Avenue lane closures. And
finally, the tied-arch design provides
beauty and character to serve as a
signature RTD light rail structure.”
Typically, the longer the span
of a tied-arch bridge, the taller the
arches. The 6th Ave. bridgeʼs arches
angle inward so that their width at
the ends is 43 feet while their width
at the crown is only 16 feet. Each arch
is designed to withstand a compressive force of nearly 3 millions pounds.
“The bridge design includes
ballast to provide vibration dampening of the structure,” adds Freeman,
“and to simplify construction of the
tracks across the bridge. The weight
of the ballast alone weighs more than
all of the structural steel in the tied
arch. The design is extremely efficient, with connecting arch members
following the natural load path of
compression.”
In addition to 6th Ave., bridges
over Indiana Street, South Platte
River and Consolidated Main Line
railroad tracks east of I-25 feature
lower maintenance weathering steel
construction in diverse designs.
Due to its aggressive curvature and
length of over 1530 feet, the Indiana
Federal Blvd. bridge, which will carry
automobile traffic over Lakewood Gulch,
two light rail tracks and two pedestrian
pathways, is being reconstructed as part
of West Corridor project for CDOT, who
is paying for the work. Construction has
necessitated avoiding two existing sewer
lines which are over 30 feet deep.
Bridge over the interchange of Indiana St. and 6th Ave. is the
longest structure on West Corridor with an overall length of
1531.5 feet. There are a total of 11 spans – five concrete on the
northwest, three steel in the middle and three concrete on the
southeast. Bridge subcontractor Edward Kraemer & Sons and its
engineer, Littleton-based Summit Engineering Group Inc., worked
to come up with a solution to allow the steel girders to be placed
before post-tensioning of the concrete box girders was completed.
bridge incorporates precast concrete
girder approaches with curved, variable-depth steel girders to cross the
intersection of Indiana and 6th Ave.
and its two on-ramps. Approach
structures were post-tensioned while
the steel girders were being placed,
which required relocating the posttension ducts from their position in
the original precast girder design.
Rails will be attached directly to
the deck – with no ballast – in direct
fixation design.
The seven other rail bridges are
designed using precast, prestressed
concrete bulb-T girders and reinforced concrete piers, the most economical design choice. Many of the
bridges also serve as a conduit for
utilities. At Federal Boulevard, a
new bridge is being built over Lakewood Gulch for vehicle traffic on the
boulevard while West Corridor tracks
run below the structure. The new
bridge and other improvements will
also stabilize Lakewood Gulch and
increase its flood capacity.
The bridge at Wadsworth Boulevard will include the LRT station
above the boulevard and will be the
centerpiece of a new commercial,
employment and residential center
spread over 60 square-blocks, connecting with recent nearby urban
renewal projects that have helped
invigorate City of Lakewood. Betterments to the structure and station
are being paid for by the City.
Two companies known for bridge
building expertise are subcontractors to Denver Transit Construction
Group on West Corridor. Edward
Kraemer & Sons Inc. is the contractor for eight bridges and Lawrence
Construction Co. is constructing five
bridges and the tunnel under I-70.
From an architectural standpoint,
the West Corridor team has designed
its bridges to be both functional and
aesthetically appealing. Finishing
touches to the concrete abutments,
piers and decks as well as final color
and overall appearance are important
to the West Corridorʼs many stakeholders, and DEAʼs design team
collaborated with Denver-area artist
David Griggs to ensure each fit into
their respective surroundings. G
Due to scheduling, the Colfax Ave. bridge was built without approach ramps, which
will be added at a later date.The one-track, six-span bridge is 696 ft. long and 20
ft. wide. To reduce weight, the rails are attached to the deck with no ballast or ties.
Some FasTracks Lines LRT, Others CR – Whatʼs The Difference?
L
ight rail is a common form of urban
mass transit these days, yet as
systems branch out to provide more
regional service, as Denver metroʼs
Regional Transportation District is
doing, designers are looking to commuter rail instead. The two systems
differ in one very important way: CR
has the increased size and power
necessary to run alongside and on
the same tracks as commercial
freight trains. That allows RTD to
design its system to take advantage
of existing freight and/or passenger
rail corridors where usage agreements can be made with, basically,
one owner instead of the hundreds
likely involved during the ROW process. Thatʼs huge.
CR is a passenger train that can
be powered by either diesel fuel
or electricity, while LRT is powered
solely by overhead electrical lines.
CR vehicles operate on a standard
railroad track gauge and are built
for longer service distances, with an
interior designed to provide a comfortable ride, much like those found
on RTD's regional and skyride bus
routes. Conversely, LRT has the
ability to operate along crowded
streets and within tight urban corridors with frequent stops, where quick
acceleration and deceleration are
necessary.
RTDʼs objective is to operate all
CR, LRT and bus routes safely, reliably and efficiently and to integrate
CR operations with LRT and bus
service for the greatest convenience
to the public. The CR system is a
means by which integration of transportation services will assist the region in meeting clean air standards,
alleviating traffic congestion and
improving the overall quality of life in
the area. CR vehicles will typically be
operated manually.
CR, the mode chosen for North
Metro, Northwest, East and Gold
Line corridors, forms an integral part
of RTDʼs comprehensive transit
LRT is powered solely by overhead
electrical lines, while CR can be
powered electrically (as shown in
rendering below) or by diesel fuel.
program. Currently, no such service
exists in the Denver metro area,
and CR presents its own unique
needs and challenges. RTD will
operate CR as part of a fully integrated mass transit system which
also includes LRT, local bus routes,
express bus routes, regional routes,
shuttle bus routes and demandresponse service for passengers
with disabilities.
Presently, RTD is planning to
use Electric Multiple Units on three
CR lines and Diesel Multiple Units
on one. EMUs are powered from an
overhead contact system (OCS)
wire via 25 Kv alternating current.
DMUs are powered by a diesel engine similar to that of a bus engine.
Some track will be used exclusively
by RTD for passenger CR operations, within or beyond private railroad ROW, and other track may be
shared jointly by RTD, Union Pacific
and BNSF Railway.
RTD provides transit services
to one of the largest geographical
districts in the United States – approximately 2400 square-miles. Service
area population in 2009 was approximately 2.5 million. Size of the service area, population density, nature
of the roadway system and development of suburban activity centers
has led to the creation of a public
transportation system with a wide
range of service types intended to
most effectively serve all citizens. G
RTD Project Manager Dennis Cole Established West Corridor Decorum
O
nly days after celebrating the
start of full construction of the
West Corridor LRT project and only
days before his 61st birthday, RTDʼs
West Corridor Project Manager
Dennis Cole suffered a massive
stroke and died on Friday, June 26.
An architect who joined RTD in 2000,
Dennis had a brilliant mind that can
be seen through a number of projects
in metro Denver, including the parking structure at Sheridan Blvd. and
US 36, light rail platforms along
Central Platte Valley Line, the barrel
vault at Denver Union Station and
his most-recent architectural jewel
– the pedestrian bridge at McCaslin
Boulevard. But it was in his role
on the West Corridor project that
demonstrated both his professional
and personal qualities to the greatest
number of people.
Dennis shepherded the environmental study for West Corridor from
start to finish and through his diligence, led the team to complete
final design and moved the project
into construction. After being appointed project manager in July 2001,
he walked the Corridor, alone with
his thoughts, to familiarize himself
with the entire projectʼs scope. As
efforts progressed, he regularly rode
the route on his motorcycle to witness
firsthand both the teamʼs challenges
and performance. He was the face
of the West Corridor project from its
beginning, taking the lead in forging
partnerships with government and
private stakeholders as well as the
general public.
In July 2009, RTD assigned Jim
Starling, PE, to take over as project
manager for West Corridor. A CSU
graduate and 13-year RTD employee,
Starling has extensive light and
commuter rail experience. He had
been serving as engineering project
manager for FasTracksʼ North Metro
Corridor, the proposed 18-mile LRT
line between Union Station and
162nd Avenue, since 2006. Starling
also served as light rail engineering
manager on Southeast Corridor, as
project manager on Central Platte
Valley Spur and helped manage
construction of Southwest Corridor.
“Jim Starling has been a major
contributor to the successful construction of RTDʼs previous light
rail projects, and we are confident
that his knowledge and expertise
will be a tremendous asset to the
West Corridor,” said Rick Clarke,
RTDʼs assistant general manager of
Capital Programs.
“What I knew about the West
Corridor came mostly from listening
to Dennis in group meetings,” Starling says, “but he left everything in
order for the project to continue without him, which is a real testament to
his character. He was a good friend
and we see his passion in the project every day.”
As Starling settles into the new
position, construction continues with a
team of contractors working throughout the corridor. He expects to see a
lot more of Dennis Coleʼs efforts and
influence as progress continues.
“Dennisʼ expertise was showcased with the erection of the projectʼs signature bridge over 6th Avenue in April,” adds Starling. “Dennis
was able to get CDOT to agree to
close the highway for two weekends.
This is unheard of – CDOT typically
allows only lane closures. This was
a unique partnership for a mostunique situation.”
The joint decision by CDOT, RTD
and Denver Transit Construction
Group to completely close the highway for one full weekend reduced
what could have been months of lane
closures. All lanes of the highway
were closed at 10 pm Friday and
scheduled to open at 5:30 am on
Monday. Efficiency of operations
allowed the construction team to
open the highway at 12:30 am Sunday, more than a day ahead of the
allowed time.
“Dennis was able to build upon
the relationship developed with
CDOT during T-REX,” Starling concludes. “That is a precedent I appreciate and plan to continue.” G
Dennis Cole was the face of RTDʼs West Corridor project, shepherding the projectʼs EA and working firsthand with stakeholders until his untimely death in 2009.