ASLA 2012 Professional and Student Awards Program
Concealed Identification and Credit Form
Entry Number: PA-423
Project Title: I-70 Mountain Corridor Aesthetic Guidance
Official Entrant: Design Workshop, Inc. – Aspen, Colorado
Lead Designer (if applicable): Design Workshop, Inc. – Aspen, Colorado
Landscape Architect of Record/Firm (if applicable):
Richard W. Shaw – Design Workshop, Inc. and
Kevin Shanks, THK Associates, Inc.
Client/Owner (if applicable):
Please indicate if you wish client name to be kept confidential: ___yes _x__no
Image 1 Design Workshop, Inc.
Image 2 Design Workshop, Inc.
Image 3 Colorado Department of Transportation
Image 4 Design Workshop, Inc.
Image 5 Design Workshop, Inc.
Image 6 Design Workshop, Inc./THK Associates, Inc.
Image 7 Design Workshop, Inc./THK Associates, Inc.
Image 8 Design Workshop, Inc.
Image 9 Design Workshop, Inc.
Image 10 Design Workshop, Inc./THK Associates, Inc.
Image 11 Design Workshop, Inc./THK Associates, Inc.
Image 12 Design Workshop, Inc./Colorado Department of Transportation
Additional Project Credits: Credit is free, so please include consultants, contractors, plant and
product sources, publishers, etc., and specify their roles exactly as you would like them to appear
in promotions if the entry receives an award.
Landscape Architects: Design Workshop, Inc.
THK Associates, Inc.
Project Engineer and Lead Consultant CH2MHILL
(CSS Process): Boulder, Colorado
Public Facilitator: Noyes and Associates
Project Title: I-70 Mountain Corridor Aesthetic Guidance
Project Location: Denver to Glenwood Springs, Colorado
Project Type: Comprehensive Design Criteria and Guidelines for Interstate Transportation Corridor
An innovative model for roadway design, this document challenges existing practices and regulations, redefining the
application of aesthetics to highway design. It provides a vision for an entire interstate corridor rather than defining it by
construction phases or funding increments. The document identifies the important relationship between landscape and
highway, encourages the interface between wildlife and humans, protects the environment, and ultimately, connects the
user to the surrounding region.
Redefining Aesthetics | The Interstate 70 mountain corridor stretches for 144-miles through four counties, multiple
communities, and thousands of acres of state and federal lands. In some areas, it is considered an engineering marvel of
the interstate highway system, while in other areas, it is a blight on the landscape. Various construction methods have
been applied within the confines of a challenging and mountainous terrain, fragile river environment, and ever-changing
seasonal weather issues including a variety of tunnels, bridges, viaducts, retaining walls and elevated road sections, many of
which cantilever over the ecologically-fragile Colorado River. Good or bad, all point to the need for consistent landscape
treatment to bolster the technically rigorous highway design. Rising over 5,000 vertical feet in elevation from the tall grass
foothills of Denver to the alpine crest of 11,200’ at the Continental Divide and traversing five life zones, I-70 connects some
of the most valued economic, recreational and visual resources in the state. More than 10 million cars pass through the
Eisenhower Tunnel each year. It is one of the most highly visible corridors in the intermountain region, connecting the
West Coast to the Great Plains.
An essential component of the Aesthetic Guidelines is the development of standards for two separate alignments, one for
each travel lane, based on topographic conditions and other existing circumstances including rock-cuts, community
connectivity, sound barriers, and wildlife corridors. Additionally, the guidelines address the environmental context in which
highway facilities are built, including their relationship with the land, surrounding hydrology, wildlife corridors, plant
palette, adjacent communities and recreational resources, creating an environmental, visual and community-based vision
for the landscape in which these facilities are located. Finally, this vision addresses the design character of new
construction along the corridor, including landscape disturbances, sustainable practice, new standards of design, and a
transportation corridor that exhibits a thoughtful consideration of the interface between users and the environment. In
this project, aesthetic design is made an integral part of the engineering process rather than an after-thought. The intent
of the guidelines is to connect the transportation user to the larger setting, and to complement the surroundings with a
highway and corresponding facilities that tread lightly on the landscape.
Redefining the Place of Aesthetics in Transportation Design | The Aesthetic Guidelines are a model for roadway design,
promoting aesthetics as an integral part of the process at the onset rather than applying aesthetic solutions after the
roadway is designed. Based on the establishment of engineering design criteria that address design speed, roadway
alignment, slope cut and fill, areas of disturbance and structure design for bridges and walls, the guidelines are embedded
in the technical road design from concept to construction documentation. Many of these design criteria have been
developed for the project because of visual and design character considerations, not simply functional concerns. And,
because these design criteria have been developed with aesthetics in mind from the beginning, they represent a new way
of managing a highway corridor. Any new construction within the corridor will occur within the footprint of historic or
current disturbances. These criteria have been developed and adopted because they represent a holistic approach to
roadway design that not only enhances safety, mobility, and sustainability, but also considers a corridor for the 21st century
which includes both an advanced guideway transportation system and additional vehicle carrying capacity, all the while
reducing maintenance through design and engineering.
Once the engineering criteria were established, objectives and strategies were formulated for the four Design Segments
that make up the corridor - “Western Slope Canyons and Valleys”, “Crest of the Rockies,” “Mountain Mineral Belt,” and
2012 ASLA Professional Awards
Analysis and Planning Category
“Front Range Foothills.” Corridor design segments are identified by their physical and cultural characteristics, including
human geography, land form, community character, settlement patterns and life zones. The segments, which define the
design character of the highway based on its environmental and cultural setting, are the foundation upon which the
Aesthetic Guidelines are structured as well as the foundation for stakeholder and aesthetic working group input.
The aesthetic working groups were comprised of citizen and stakeholders located within defined areas that warranted
special attention due to their unique issues, complex situations, and multiple user groups. Issues and challenges in these
areas include heavy traffic, high accident rates, plans for future high-speed rail facilities, topography, water and wildlife
corridor interface, access to recreational resources, and relationships with adjacent communities. Areas of Special
Attention reports provide goals and objectives for theses areas, outlining a process for moving forward with future
improvements – ensuring that multiple options will be discussed.
Crafting a Roadmap for Future Implementation | Heretofore, aesthetics in roadway design have typically been applied
once a project is almost complete. This project is different because it suggests that aesthetics are integral to roadway
design and alignment in the establishment of engineering criteria. The Aesthetic Guidelines provide objectives and
strategies for accomplishing this vision, specifically defining a transportation and land relationship, as well as identifying
structures such as bridges , walls and safety features, a color and plant palette for each design segment, limits of land
disturbance, earthwork and grading, treatment of hydrologic features and wildlife, maintenance, signage and access to
cultural and recreational destinations and guidance for future advanced transportation systems planned to connect Denver
to the western slope.
The I-70 Aesthetic Guidelines integrate a modern design character with elegantly engineered transportation facilities that
reflect function and simplicity throughout the corridor. Because the landscape under, adjacent to, and beyond the
structures supporting transportation facilities is rugged, organic, and natural, any attempt to make these facilities appear
less than natural diminishes the concept, creating a design rift that stands in bleak contrast to the existing landscape.
Equally important is the linkage of land and transportation features. Therefore road geometry is meant to fit existing land
forms, maintaining a sinuous and continuous flow.
Fostering Sustainability | The Aesthetic Guidelines defer to community context, emphasizing the existing natural
environment, scenic integrity and the need for safe and efficient travel. Hydrologic features affected by the construction of
a transportation facility construction will be protected and enhanced for their ecological and scenic value. Because the
native topsoil contains a natural seed bank complete with a moisture-retaining capacity and nutrients to support plant
growth, it is required that, throughout the corridor, all topsoil be salvaged, stored and redistributed. Ultimately, successful
re-vegetation and long-term restoration is achievable when these resources are managed properly. Wildlife corridors and
crossings are integral to the design in order that the natural movement of animals remains intact and undisturbed by
geographic or physical barriers. Quality of life for residents and workers along the corridor can be maintained by
implementing thoughtful landscape, earthwork, and structural transitions between transportation alignments and adjacent
community-oriented land uses. Corridor designs that facilitate pedestrian and multi-modal connections across the
transportation corridor, as well as connections to existing recreational and cultural resources strengthen the mobility of a
community and encourage successful land use patterns and circulation.
Multi-Disciplinary Collaborative Effort Yields Implementable Results | In order to develop a successful and context-driven
design for the corridor, it is imperative that all stakeholders remain involved throughout the life of the project. To date, a
diverse array of stakeholders — from truck drivers to tourists, business owners to snowboarders, and environmental
champions to cultural/history constituents — have contributed to shaping the future of the corridor. The public
engagement process creates a direct link between stakeholder issues and the design process, including design criteria,
design guidelines and areas of special attention. The guidelines foster a methodology for coalescing communities and
ensuring that all stakeholders continue to have a voice.In
addition, the guidelines are a ‘living’ web-based document in
which updates and additions can be tracked through a website for the life of the project. The website provides interactive
maps, links to applicable documents, related studies and pertinent regulations, as well as contact information for
stakeholders to provide ongoing input. CDOT training has been incorporated into the project.
ASLA 2012 Professional and Student Awards Program
Captions: I-70 Mountain Corridor Aesthetic Guidance
Image 1: An engineering marvel, the 144-mile stretch of interstate crosses the highest elevation of any
interstate. The Aesthetic Guidance lays a foundation for a new approach to roadway design, elevating
aesthetics to the same level as other engineering and functional design parameters.
Image 2: The Aesthetic Guidance defines the highway design process differently by making aesthetics for land,
community, highway and future rapid transit rail an integral part of the design process at the onset rather than
applying aesthetic solutions after the roadway is designed.
Image 3: Future projects across the corridor have the potential to create elegant consistency. The Engineering
Design Criteria provide principles, objectives and strategies to the future managers and designers of
transportation facilities to guide the projects to a desired outcome.
Image 4: The Aesthetic Guidance began with defining engineering design criteria followed by objectives and
strategies for the entire mountain corridor and each design segment. Lastly, objectives and strategies were
defined for areas of special attention within each design segment.
Image 5: To achieve context sensitive design, the Aesthetic Guidance is divided into Design Segments
presenting specific objectives and strategies appropriate to each. Segments were determined by various
natural and human geography factors, representing a systematic definition of how context is defined.
Image 6: The process studied landscape typology as a way to define Design Segments for which the design
guidelines and public outreach are structured. This exercise led to guidelines that encourage a roadway that is
subservient to the landscape and create a light touch on the land.
Image 7: Aesthetic working groups assisted in defining issues, generating information, structuring design topics
and creating recommendations. A diverse array of stakeholders — from truck drivers to tourists, business
owners to snowboarders, and environmental champions to cultural/history constituents — have shaped the
Image 8: The aesthetic ideal for each segment was converted to engineering criteria, which have been
adopted as an approach to enhance safety, mobility, and sustainability while reducing maintenance. These
criteria are the focus of the design created by the aesthetic needs of the highway features.
Image 9: The Design Criteria and Aesthetic Guidance provides strategies to create a highway and transit line
that heals the existing landscape and creates new capacity. The strategies build on past successes and
address unresolved issues.
Image 10: The facilities of the highway and future transit line have been designed to address the specific
context and issues. This page of the guidance requires the use of structured and elevated solutions to minimize
the level of disturbance on steep slopes.
Image 11: Many wildlife corridors encompass the I-70 corridor providing habitat for elk, mule deer, bighorn
sheep, mountain goat and black bear. Providing well-designed underpasses, open span bridges, and wildlife
fencing in appropriate locations will create safer alternatives for wildlife crossings.
Image 12: The corridor-wide guidance is implemented through a living web-based format to be updated and
improved for the next 50 years. The website provides information, guidance and tools for design teams to
enhance the mountain corridor’s legacy for future generations.
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