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A Different Kind of Project: Building Future AEC Professionals with CU Boulder

Posted on by Otak Staff

A common thread within the architecture, engineering, and construction (AEC) industry exists in creating lasting impact. While this theme naturally applies to work that aims to improve lives in communities from one generation to the next, it’s also about preparing the next generation of professionals to continue that work.

At the University of Colorado, Boulder, the CVEN 4899 Senior Design course takes a different approach to building future AEC professionals by giving students a real-world example project to put their knowledge into practice. The project is part of Otak’s work on South Boulder Creek and several leaders from the multidisciplinary expertise involved participated in the classroom and in the field. Their hope was to lend their perspective as mentors to advancing an educational system where a focus on technical knowledge often doesn’t include the value of practical experience.

Quote from Matt Morris about the CU Boulder Capstone project.

Understanding how complex projects go from concept to completion involves familiarity with nuanced aspects of decision making in each phase, including stakeholder engagement, technical design, constructability, budgeting, and interdisciplinary coordination. This course helps balance the gap between hard and soft skills in the complete design and construction process, equipping students with a well-rounded start toward successful careers in the industry.

In this blog, we’ll dive into the details of this unique capstone project and the information presented to guide it across four distinct elements. Read on or skip ahead:

Students of the CU Boulder Capstone project gathered at the project site.
Image of Chris Romeyn presenting in the classroom for the CU Boulder Capstone project.
Students in the field as part of the CU Boulder Capstone project.

The Project – A Stream, Two Structures, and the Solutions of Multidisciplinary Work

In the backyard of CU Boulder’s campus is a nine-mile stretch of South Boulder Creek that extends from Eldorado Canyon to its confluence with Boulder Creek. It represents one of several stream sites identified for improvement by Boulder Flycasters (a local chapter of Trout Unlimited) after multiple studies in the area. The subsequent Stream Management Plan recommended the modification or replacement of multiple structures while the City of Boulder Open Space & Mountain Parks Department aimed to improve the functionality of all water crossings across their trail network in the area.

The collective goals of a hypothetical client, The South Boulder Creek Alliance, took shape in a request for proposal (RFP) that combines two projects near the South Mesa Trailhead. One focuses on modifying or replacing the Davidson Diversion structure, and the second on the pedestrian access bridge crossing South Boulder Creek as part of the Mesa Trail.

Aerial view of the project site for the CU Boulder Capstone Project, including the two structures.

Through this course, students were asked to develop hypothetical proposals for this real-world project. In developing their designs for each element, they were challenged to balance stakeholder needs, reduce costs through innovative materials and construction methods, and minimize impacts to the environment and public—both during construction and in the long term. Several presentations from industry professionals would guide them along the way, all with a focus on sustainability and resiliency considerations.

Assessing Water Resources and Environmental Conditions

Understanding water resources is an essential component to civil engineering, which of course is accentuated when a stream is involved. It’s a concept very familiar to Tracy Emmanuel, a geomorphologist and team lead for environmental as well as water and natural resources work at Otak, who—alongside colleagues Chris Romeyn and Maddie McNamee—brought expertise to this course in the classroom and the field. While Chris and Maddie led a tutorial on hydraulic modeling, Tracy guided students through her team’s approach to water-related aspects of projects with an emphasis on the types of questions they ask in the project process to uncover the right design solutions—rather than simply providing the answers.

Quote from Tracy Emmanuel about her involvement with the CU Boulder Capstone project.

Using this information, students examined the project area’s floodplain and how the flow of the stream impacts the design in a number of key ways:

  • Determining watershed hydrology and waterway flows as they relate to water rights, fish passage, and with consideration of an expansion project of the upstream Gross Reservoir Dam
  • Examining a floodplain assessment of impacts to 100-year and 500-year floodplain boundaries in relation to those published by FEMA and local agencies
  • Completing hydraulic analysis to determine placement and impact of both the diversion structure and potential bridge crossing. 
  • Determining scour from a 500-year storm event and channel erosion protection for the structures

These areas not only enhanced the students’ understanding of water resources engineering but also underlined the importance of designing for the long-term ecological health of the area and maximizing its value to the surrounding community.

Making Context-Sensitive Structural Design Decisions

Structural design is about more than just crunching numbers—it’s about understanding how context, constraints, and client priorities shape a project. David Graff, a structural engineer at Otak, provided students a window into better understanding the how that surrounding context impacts the structural design process, while remaining rooted in real-world conditions.

Quote from David Graff about his involvement with the CU Boulder Capstone project.

David emphasized that before even beginning detailed calculations, engineers must make critical decisions about structure type, channel impact, materials, constructability, and aesthetic expectations. He also highlighted the importance of asking the right questions—What problems is the client trying to solve? What’s the budget? Are there successful precedent projects to draw from?

To demonstrate this process, he shared the structure alignment selection process behind the 19th Street Pedestrian Bridge, which exists right on CU Boulder’s campus. He used the project as an example familiar to these students, illustrating how thoughtful engineering, paired with client engagement and project constraint understanding, leads to a successful and unique design solution.

These insights aimed to aid the students as they worked through the structural and geotechnical aspects of the project:

  • Describing existing site conditions, including subsurface conditions and soil profiles
  • Determining if any elements of existing structures can be reused in the final condition
  • Evaluating the pros and cons of different structural materials and systems for the pedestrian bridge design
  • Considering preventative maintenance for the structures and those associated future costs

The opportunity to navigate working with multiple disciplines and stakeholders gave students a fuller understanding of the structural design process and the high-level decisions that come with it.

University of Colorado Varsity Pond Bridge and Dam Improvements

See the Project

Take a closer look at how a historic landmark is rehabilitated to ensure its structural integrity and access to the campus community for generations to come.

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Building High-Performing Teams with Balanced Skills

Technical expertise is essential, but the ability to work well with others and communicate effectively is also critical to a project’s success. Henry Alaman, Otak’s Colorado Regional Director and a member of the owner’s representative team, shared with students the importance of balancing technical skills with the soft skills that aren’t always covered in traditional engineering coursework.

Quote from Henry Alaman about his involvement with the CU Boulder Capstone project.

Henry spoke about how interpersonal skills influence both the pursuit of projects and their ultimate success. From team collaboration to community engagement, the ability to build relationships and gain buy-in from stakeholders can be an essential piece of the project process.

To reinforce the importance of collaboration, and communication, Henry led an interactive team-building exercise that encouraged students to break down barriers and avoid the siloed thinking that can hinder progress in interdisciplinary teams.

Considering Constructability and Managing a Project to Completion

The best design in the world won’t matter if it can’t be built efficiently. That was central theme from Patrick Pease, a leader in Otak’s construction management group, who presented the practical realities of turning design concepts into built environments.

Patrick walked students through the various steps in the construction process—from initial planning to regular coordination with owners, municipalities, and contractors. He stressed the construction phase being where most major cost fluctuations occur, making coordination crucial to maximizing project value. Proactive communication is one key to avoiding these issues by resolving disputes quickly, maintaining schedules, and keeping projects on budget. To drive this point, Patrick shared two real-world examples that showed opposing results. One—CO7 and SH119—was executed efficiently due to strong stakeholder coordination and planning. The other experienced delays and cost overruns due to poor coordination and lack of clarity between parties.

Quote from Patrick Pease about his involvement with the CU Boulder Capstone project.

With the aim of ensuring their designs could be completed, the students’ proposals included various aspects of project constructability:

  • Creating a list of stakeholders, including their role and involvement, who need to be involved during active construction
  • Providing strategies for avoiding public interruptions as well as any needed closures or detours to the trail system
  • Mitigating risk and impact to the environment, including fish spawning in the area
  • Creating a detailed cost estimate along with a design and construction schedule with phasing plans

A close look at the construction phase helped students understand how critical it is to build strong working relationships early and sustain them throughout a project’s lifecycle.

Bridging the Gap Between Classroom and Career

By simulating a true design-build environment, the CVEN 4899 Senior Design course gives students invaluable experience beyond textbooks. Otak is honored to support these future AEC professionals with a first-hand look at the full project process from a multidisciplinary environment.

As a firm committed to the professional development of our people and the improvement of our communities, we see investing in the next generation not just as mentorship but central to our mission.

Learn What It’s Like to Work at Otak

Roadway Engineering: Creating Community Connections

Posted on by Otak Staff

A cornerstone of any growing community is its connectivity. Roadway engineering provides more than just conduits for cars; it forms the framework for mobility in a community that leverages a variety of modes of transportation.

Infographic showing three types of roadway and some benefits they provide to community connectivity.

A well-designed transportation network featuring different types of roadways can have widespread impact on economic development and individual wellness. This includes improvements that ensure all areas—especially underserved populations—have access to jobs, essential services, and amenities as well as healthier lifestyles through reductions in emissions and the promotion of active transportation. In this blog we discuss how roadway designs exist at the intersection of planning and transportation engineering to support the growth of healthier, more sustainable communities.

Read on, or skip ahead:

What is Roadway Engineering and Its Importance?

Roadway engineering is the planning, design, and construction of transportation infrastructure that enhances existing roadways or establishes new connections within a community. The practice integrates technical expertise, urban planning, and environmental considerations to develop safe, efficient, and accessible transportation systems that serve both current and future needs.

The design process starts with an assessment of existing conditions, including topographic mapping, survey and GIS, to understand site constraints. From there, engineers develop roadway layouts that meet design and safety standards. The final design incorporates permitting requirements, cost considerations, and agency coordination to ensure a smooth transition from planning through construction. The end result is a completed roadway that enhances connection across a community.

Key Roadway Engineering Project Considerations

Aerial view of the NE 40th Water Quality Facility.
NE 40th Water Quality Facility

Stormwater Infrastructure and Low Impact Development

An extremely common aspect of roadway engineering involves the inclusion of stormwater infrastructure considerations. While accounting for increased impervious surfaces and polluted runoff, stormwater features reduce flooding and improve water quality for a community.

A replacement culvert and fish passage features as part of improvements to 171st Parkway.
171st Street Urban Parkway

Culvert Replacement and Environmental Mitigation

With new development comes the potential for negative environmental impact, but proper analysis of natural resources can mitigate adverse effects. Existing culverts are notoriously inefficient and are also among the most common barriers to fish passage. Today, culverts are being replaced to protect aquatic habitat, reduce flooding, and preserve water rights for property owners.

View down to 30th and Colorado protected bike underpass.
30th and Colorado Underpass

Pedestrian Features

An important piece of roadway engineering is consideration of how it facilitates more than just cars. Multimodal design gives communities options for how they get from point A to point B, all while reducing carbon emissions and promoting physical health through active transportation. Emphasizing pedestrian mobility features like pedestrian bridges, protected bike lanes, cross walks, and traffic stripping reduces traffic conflicts for all.

An intersection along the updated Tolt Avenue corridor.
Tolt Avenue Central Business District Improvements

Traffic Control Elements

Safety is the top priority of any roadway project. With updated traffic signals and signage, drivers are more aware, creating a safer environment for themselves and pedestrians. As the design of a roadway considers number of lanes and width, control of speed can also be effectively managed.

People at the Lynnwood Community Transit Bus Rapid Transit Orange Line station.
Swift Bus Rapid Transit (BRT)

Transit-Oriented-Development

A healthy transportation network is a diverse transportation network. As roadway projects increase in size, so do opportunities to incorporate multimodal features. This can include accommodating mass transit with new stations, specialized lanes, or connection to adjacent trail systems. All ultimately contribute to traffic calming, creating a more connected community.

From small neighborhood streets to large arterials, each roadway type must be designed with the specific needs of the community in mind. A critical aspect of any design is engaging with the public to ensure buy-in and minimize disruption. The larger the initiative, the more essential public outreach becomes, and each project presents its own unique impacts to the connectivity of the communities it serves.

Types of Roadways and Their Impact on Communities

Different types of roadways serve unique, though connected, purposes in a transportation network. Their design often begins with comprehensive planning efforts which help identify the transportation needs of a community. Potential projects can then be developed with the focus of serving both community and client goals.

Neighborhood Streets

Neighborhood streets are designed with a primary focus on safety and accessibility, often placing an emphasis on pedestrians, cyclists, and access to public transit. The more limited scope of neighborhood street projects makes cost-effective construction strategies vital to fit within local budgets.

With this localized focus on enhancing connectivity and accessibility, neighborhood streets also typically include ADA-compliant sidewalks and crosswalks while speed bumps or curb extensions are among traffic calming measures. This roadway type requires extra attention to minimizing impact on adjacent properties while maximizing the benefits to those who call the neighborhood home, including the public assets that often exist in the area.

Tualatin, OR Adds Safe Routes to School

View of a pedestrian crosswalk and landscape as part of pedestrian safety improvements around Tualatin Elementary.
View of widened sidewalk and signage as part of pedestrian safety improvements around Tualatin Elementary.

Among some of the most important improvements that can be made to neighborhood streets are those that create a safer environment for children that play and travel in the area. For many parents at Tualatin Elementary, it was clear that updates to the neighborhood streets could make a real difference for the kids walking and biking to and from school.

Graphic with a quote from a community member on the impact of roadway improvements and the safe routes to schools program.
Source: KOIN 6

As part of Safe Routes to School (SRTS) programs, which provides grants for these types of improvements, work on 95th and Avery made a variety of upgrades to enhance pedestrian safety, particularly for the kids of Tualatin Elementary.

Multiple intersections were improved with high visibility striping in crosswalks, rectangular rapid-flashing beacons (RRFB), and other features to create safer pedestrian crossings and reduce conflicts with vehicles. Deficient sidewalks and gaps were replaced to further enhance the pedestrian experience.

Mid-Size Collectors and Corridors

Mid-size collectors and corridors serve as vital connections between neighborhoods and larger roadways. This roadway type supports moderate traffic volumes and often incorporates improvements that enhance transportation operations and facilitate flow between developing areas.

Corridors generally aim to improve access to commercial areas, parks, and transit hubs in response to increasing traffic demand. As part of planning efforts, these improvements are sometimes made in anticipation of future development. The larger scope often involves coordination with utility companies and various agencies, as they can have a substantial impact on not only the community but the surrounding environment.

Silverdale, WA Sees Reduced Congestion and an Enhanced Waterfront

Designed a 240-foot, four-lane bridge and widened road
Designed a 240-foot, four-lane bridge and widened road

The community of Silverdale had long looked to improve on poor waterfront access. Where the Clear Creek Estuary crosses under Bucklin Hill Road and meets Dyes Inlet, high traffic was common which was especially problematic considering its semi-rural setting. Altogether, the area represented a missed opportunity to create an appealing place for recreation, community connections, and growth for local businesses.

Graphic with a quote from a local business owner on the impact of the Bucklin Hill roadway project.

Improvements to Bucklin Hill Road and Bridge changed that. Two additional travel lanes eliminated congestion while new bike lanes and facilities were added where there had been none. Widened sidewalks and new trail connections added to new active transportation opportunities for the community. Extensive public outreach, including the “Scout Your Route” campaign to keep the public informed of closures, minimized disruption while reducing construction duration. These improvements had a direct, broad impact on all community members, including residents at senior living facilities in the area that now benefit from greater accessibility to their local businesses.

Large Arterials and Highways

Large arterials and highways are critical for regional mobility, commerce, and overarching economic development. Linking rural and urban areas, these roadways provide communities of all sizes access to important resources like employment and healthcare in metropolitan centers, while supporting the social and cultural networks between different areas. The scale of large highway upgrades can lead to wider improvements to transit-oriented development that diversify modes of transportation and maximize project value.

These roadways often present unique engineering challenges and draw from multiple funding sources, requiring close coordination with agencies to ensure regulatory compliance. As long-term, high-visibility projects, managing timelines and minimizing construction impacts is essential to minimizing disruptions that, at this scale, can be especially costly. This includes effectively communicating project updates with the surrounding community through informational websites, local representatives, and other channels to provide clarity and achieve buy-in.

Salem, OR Supports Rapid Growth and Underserved Areas

In a historically underserved area of Salem, Oregon, where 36% of parcels are underutilized, the McGilchrist Complete Street Project is designed to enhance business development, job creation, and multimodal transportation options for members of the community. It’s part of a 20-year vision for economic growth as well as transportation safety and environmental sustainability.

Graphic with a quote from Ron Wyden on the McGilchrist Arterial project.

Considering the large and lasting impact of this work on the community, it was imperative to include them. Extensive stakeholder engagement went above and beyond, working directly with property owners, businesses, and local agencies to ensure the project addressed real community needs. These efforts led to the incorporation of refinements such as the protected cycle track and intersection realignments.

Based on feedback from public outreach, 74% of the corridor features protected bike lanes and new sidewalks. The design aims to significantly improve pedestrian accessibility while minimizing pedestrian-vehicle conflicts, resulting in fewer severe crashes and lives lost. The inclusion of $15 million of stormwater infrastructure upgrades also means this work plays a critical role in not only reducing future flooding for the community but improving habitat for fish.

Making the Complete Connection

Roadways are essential to creating vibrant, connected, and equitable communities. Because of their widespread impact, roadway projects of any size involve a diverse set of considerations to ensure that impact is comprehensive and long lasting. Through thoughtful planning, collaboration, and public engagement, Otak’s multidisciplinary teams take a cohesive approach to designing more connected communities that address current and future needs.

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Redmond Stormwater Trunk Extension and Water Quality Facility Wins Silver at ACEC WA EEA Awards

A group photo of the NE 40th Stormwater Trunk Extension and Water Quality Facility project team with client.
The Otak project team and client at the 2025 ACEC WA Engineering Excellence Awards Banquet.

This year’s American Council of Engineering Companies (ACEC) Washington Awards Banquet celebrated a variety of projects from the region that improve communities through innovative engineering solutions. We’re proud to share that Otak’s NE 40th Stormwater Trunk Extension and Water Quality Facility project was honored with a Silver Award for Successful Fulfillment of Client/Owner Needs, highlighting the exceptional work and the dedication of our stormwater planning and environmental teams to collaborate closely with our client partners.

In further developing the City of Redmond’s stormwater infrastructure, this project stood out for a design that ensures water quality for people and natural habitat alike, while encouraging investment in the redevelopment of the area.

About Phase 1: Street Stormwater Trunk Extension

Redmond’s proactive approach to stormwater management included extension of a stormwater trunkline to a new direct outfall into Lake Sammamish to accommodate future redevelopment without the need for large on-site flow control facilities. This allows for higher density in a growing urban area around the new Redmond Technology Light Rail Station.

See the Project

About Phase 2: Water Quality Facility

At the upstream end of the trunkline basin, the NE 40th Street Water Quality Facility was established to treat highly polluted runoff from 19 acres of a high-traffic roadway area. The new retrofit treatment site includes a unique leaf-shaped biofiltration facility that is viewable by pedestrians and transit center users at a gateway node within the city.

See the Project

Congratulations to our team, client, and project partners for their hard work and dedication! We look forward to continuing our mission of delivering innovative and sustainable built solutions.

Graphic with project images and an overview of the NE 40th Street Stormwater Trunk Extension and Water Quality Facility.

Two Otak Leaders Honored at DJC Women of Vision 2024

The Daily Journal of Commerce (DJC) Oregon’s annual event brought together members of the AEC industry to recognize the many accomplishments of women in the field. This year, the DJC Women of Vision Award was received by Kristen Ballou and Sarah Oaks.

Their recognition adds to a growing list of women at Otak that have been honored over the past several years:

  • 2023 – Saretta Tillmaand, Amanda Owings, Margaret Steinhilber
  • 2022 – Millicent Williams
  • 2021 – Tanya Boyer, Rachel Laura, Cathy Kraus
  • 2020 – Serah Breakstone, Tina Keller, Angela Khosa-Marangwanda
  • 2019 – Ashley Cantlon, Amy Scheckla-Cox, Teresa Huntsinger

Learn more below about each and catch a glimpse of what their peers had to say as part of the nomination process.

Meet the Honorees

Kristen Ballou, Senior Civil Engineer

Kristen Ballou speaking during her acceptance of a 2024 Women of Vision Award.

While designing transportation and utility improvements for communities across Oregon, Kristen Ballou has spent the past 24 years at Otak.

“The successful on-time and on-budget completion of Kristen’s projects was a huge part of the success of the overall Tualatin Transportation bond Program and a huge asset to our city.  The success of this program led to voter approval of a similar program for improvements in parks.”

– Mike McCarthy P.E., City Engineer, City of Tualatin

As a senior engineer, Kristen’s most significant accomplishments involve managing and designing detailed projects that provide multi-modal improvements and increased livability to local communities. An emphasis on Americans with Disabilities Act (ADA) guidelines is consistently part of her approach. This includes streamlining development of CAD labeling for ramp design now used by engineers across the organization.

Kristen has also been an active member of the American Public Works Association (APWA), a regular volunteer with the Beaverton School District Art Literacy Program, and a mentor to junior engineers and designers.

 

Sarah Oaks, Director of Otak CPM

Sarah Oaks holding her Women of Vision Award.

Beginning her career as an AmeriCorps Volunteer at Portland Public Schools (PPS), where she was a founding member of the Office of School Modernization, Sarah Oaks now provides leadership for Otak’s work in comprehensive project management.

“Sarah maintains a sense of stewardship alongside a strong lens of investment in people and culture. She routinely evaluates business growth from a perspective of how to support pathways for professional development of staff, creating a culture of excellence and attraction that people want to continue to be a part of.”

– Shawn Klinkner, Senior Project Manager, PM/CM, Otak

As her career has progressed, she’s continued volunteer and mentorship work with industry groups like the ACE Mentor Program. She has also kept a strong focus on public work, supporting numerous school bonds and central city revitalization efforts. In growing Otak’s PM/CM portfolio across multiple market segments, Sarah has also led a variety of internal initiatives around professional development. From supporting an international exchange program to the implementation a mentorship program, Sarah’s impact has led to stronger ties within Otak’s areas of expertise and has ushered significant growth of individual team members.

 

National Public Works ‘Project of the Year’ Awarded to 30th and Colorado Underpass at APWA 2024

The 30th and Colorado Underpass project team accepting the National Public Works Project of the Year Award.
Kevin Dooley (second from left) and other members of the 30th and Colorado Underpass project team accepting the APWA Public Project of the Year Award.

During this year’s American Public Works Association (APWA) event in Atlanta, GA, the 30th and Colorado Underpass was awarded National Project of the Year for its place as a public infrastructure project that promotes excellence in design. After opening a year ago, the project has successfully added safety improvements to a previously dangerous intersection while also advancing the City of Boulder’s multimodal transportation goals.

“This year’s award recipients have shown what happens when you fulfill your commitment to making your community a better place.”

– APWA President Gary Losier, PEng.

The project was also featured during the annual National Association of City Transportation Officials (NACTO) 2023 Designing Cities Conference which was hosted in Denver. Site visits across the area showcased projects that improved access to quality transportation infrastructure, with a particular focus on progressive multimodal networks. Led by our Colorado transportation and structural engineering teams, the 30th and Colorado Underpass joins our list of award-winning work.

About the 30th and Colorado Underpass

Panoramic view of the 30th and Colorado protected bike intersection and underpass.At the heart of an essential transportation corridor for the University of Colorado, Boulder campus, the 30th and Colorado Underpass represents the city’s first-ever fully protected intersection. The design places an emphasis on multimodal infrastructure and pedestrian safety. Highlighting lighting, landscaping, and public art features aimed at seamlessly integrating it with the urban fabric.

See the Project

 

The Art and Science of Pedestrian Bridge Design: A Guide to Functionality, Sustainability, and Aesthetics

Posted on by Otak Staff

Pedestrian bridges, also known as footbridges, are vital elements of our communities’ transportation infrastructure. While some are often crossed without much notice, others catch the attention of anyone nearby. In any case, a combination of art and science goes into the design of each structure.

Providing safe passage for pedestrians and cyclists across busy roads, rivers, railways, and other crossings, pedestrian bridges connect communities and enhance overall quality of life through active transportation. But these structures can also serve a greater purpose beyond their practical use, often providing memorable viewpoints, meeting spots, and spaces to enjoy the surrounding environment while making a design statement for communities.

Designed to last for at least 75 years, pedestrian bridges are ingrained in the fabric of the surrounding area and must be resilient to changing environmental conditions to provide long-lasting, accessible, and safe crossing. In this blog, we’ll discuss the steps of the pedestrian bridge design process and key elements around functionality, sustainability, and aesthetics that can make them fixtures of a community for generations.

Read on or skip ahead:

What is Pedestrian Bridge Design?

Pedestrian bridge design creates structures that primarily provide safe crossings for foot traffic, cyclists, and other modes of active transportation, facilitating movement between communities and enhancing its surrounding environment.

As trails grow in popularity (including in urban areas), the role of pedestrian bridges in creating accessible, interconnected networks becomes increasingly crucial. Effective pedestrian bridge design can also enhance the usability and safety of trail systems, allowing for uninterrupted and safe passage across both natural and man-made crossings.

An infographic showing common elements of pedestrian bridge design.

The Pedestrian Bridge Design Process

The design of a pedestrian bridge is a meticulous process that begins with a clear understanding of its intended usage and the specific site conditions. This process involves defining the primary purpose of the bridge, gathering detailed site information, creating preliminary designs, and finally, refining those designs into a comprehensive plan for construction.

Define Usage

The first step in pedestrian bridge design is to define its intended use. This includes understanding whether the bridge will primarily serve pedestrians, cyclists, or in many cases even small vehicles. This determines important factors related to load and bridge width. For example, bridges on pedestrian trails are typically four to six feet wide, while those on interurban trails may need to be 10 to 12 feet or sometimes even wider.

Pedestrian bridges often need to support not only foot traffic but also small vehicles such as maintenance trucks, emergency vehicles, or even snowcats. AASHTO guidelines specify that pedestrian bridges must be designed to handle a pedestrian load of 85 pounds per square foot (PSF), with additional considerations for vehicles, where loads can range from 10,000 pounds for maintenance vehicles to 54,000 pounds for emergency vehicles. In remote areas, the design might also need to accommodate equestrian use.

The rise of e-bikes is another growing consideration; while they enhance accessibility, they also introduce new safety challenges due to their speed and weight. Designers have to stay informed about varying state regulations on e-bike usage to ensure safety and accessibility for all users.

Gather Site Information

Once the intended use is defined, the next step is to gather detailed information about the site. This includes conducting surveys, geotechnical analyses, and environmental assessments. The type of crossing — whether over a stream, roadway, or railway — dictates essential design considerations like clearances. For instance, street and highway crossings require a minimum clearance of 16.5 feet, railroads 25 feet, and waterways at least two feet above a 100-year flood event.

Washougal River Bridge

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Take a closer look at how a site assessment informs pedestrian bridge design to meet multiple functional purposes, from connecting a trail system to carrying a water main, while also giving careful consideration to the surrounding environment.

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Environmental factors such as snow, wind, temperature fluctuations, and seismic activity must also be considered to ensure the bridge’s resilience. This information helps determine the appropriate location and type of abutments, as well as the length, width, and height of the bridge.

Environmental assessments are critical in identifying necessary permits and ensuring that the design minimizes impact on local ecosystems. For waterway crossings, hydrologic and hydraulic analyses provide insights into potential water levels during extreme weather events, guiding decisions about pier placement and scour protection. Other environmental considerations include preventing pollution through stormwater management and minimizing disruption to local vegetation and wildlife.

Preliminary Design and Alternative Selection

Based on the gathered data, preliminary designs are developed by structural engineers, accounting for all client and site-specific requirements. These designs include cost estimates and various alternatives, each with its own set of benefits and challenges. Preliminary sketches and renderings help visualize different options, allowing stakeholders to assess feasibility, constructability, and cost-effectiveness before making a final selection.

Final Design

The final design phase involves detailed structural analysis using specialized engineering software. This step ensures that the bridge can withstand all expected loads, including tension and compression forces. Special attention is given to fracture critical members (FCMs), which are vital components whose failure could lead to the collapse of the bridge. These elements, along with welds, are carefully identified in the structural plans.

With the design configuration set, materials are selected to meet the demands of the environment, such as thermal expansion and slip resistance. Safety and reliability are prioritized, leading to the completion of design and construction documents that detail every aspect of the bridge, from structural components to aesthetic elements.

Types of Pedestrian Bridges

While the majority of pedestrian bridges are either beam or truss structures, there are instances where other options are either required for practical reasons or chosen for design preference. 

Beam Bridge

View down part of the Kronberg Multi-Use Pathway.
Kronberg Multi-Use Pathway

Short Spans (5′ to 100′)

Beam and girder bridges provide many fabrication and construction options while also being typically more cost effective. Used for shorter spans, they are limited in girder depth and vertical clearance. While they are among the most common in pedestrian bridge design, these structures can be built with materials like steel, concrete, or timber, and can integrate bridge railings to create a unique identity.

Truss Bridge

Aerial view of the Dungeness River Bridge.
Dungeness River Bridge

Medium Spans (20’ to 150’)

With simple construction that installs quickly, truss bridges are another common pedestrian bridge type that offers a cost-effective design. While less unique, a railing that’s integral with the structure can be a fitting aesthetic for many applications. Materials for these structures are generally steel, timber, or fiberglass (FRP).

Arch Bridge

View of Varsity Pond Bridge on the University of Colorado Boulder campus.
Varsity Pond Arch Bridge

Medium Spans (50′ to 300′)

For medium spans that avoid the use of piers, arch bridges provide graceful aesthetics that can be built low below a trail profile. While more expensive, these structures can be advantageous for greater spans and limiting impact to the environment. They are commonly made of steel, concrete, or timber materials.

Cable Stay Bridge

View of the Spring Creek Pedestrian Bridge.
Spring Creek Pedestrian Bridge

Long Spans (100′ to 300′)

Offering a low profile for longer spans, cable stay bridges provide a unique look and feel compared to other pedestrian bridge options, typically showcasing a distinctive fan-like pattern created by their cable placement. Cables can be rigged in a mono, harp, fan, or star design, and similar to most other bridge types can be built with steel, timber, or concrete.

Suspension Bridge

View of the Staircase Rapids Trail Bridge in Olympic National Park.
Staircase Rapids Trail Bridge

Long Spans (200′ to 500′)

The science of long crossings and art of graceful aesthetics are combined in suspension bridge design. This structure type is especially useful for wide rivers and sites with inaccessible pier locations, often providing a statement for a community using steel, concrete, or timber materials.

Functionality Elements in Pedestrian Bridge Design

Regardless of individual goals, functionality is a core objective in any pedestrian bridge design. In creating a durable, safe, and cost-effective structure that meets community needs for decades, the design should consider a variety of factors. A focus on surrounding pedestrian and bicycle facilities, providing logical routes that encourage use and minimize the need for detours, and consideration of alternative crossing opportunities are all essential to maximizing accessibility and safety.

Wayfinding

A pedestrian bridge is only as valuable as the use it gets. The ability to find one’s way to and from the bridge as part of a broader transportation network is critical to that end.

For effective wayfinding, pedestrian bridge design should integrate with existing transportation infrastructure, ensuring that the bridge is easily accessible and does not require users to travel out of their way to cross. Creating logical connections to surrounding facilities increase the bridge’s utility and enhance the user experience. Additionally, designing a system of cohesive icons and signage not only helps guide users through space visually, but can support tourism, and establish the bridge as a gathering space and community landmark.

Approach Ramps and Accessibility

A sometimes-overlooked aspect of pedestrian bridge design are the approach ramps. Approach ramps ensure that the bridge is accessible to all users, including those with disabilities. The design of approach ramps must adhere to ADA Guidelines, which often require long ramps to accommodate the necessary vertical clearances. Ramps also provide an opportunity to add some creativity in the design that fits within the site footprint. Although these ramps can represent a significant cost, they are essential for ensuring that the bridge is fully functional and accessible.

Abutments and Piers

Serving as the foundation of the structure, abutments and piers can take shape in a pedestrian bridge design in many ways. Depending on the site conditions, abutment design can range from simple footings to more complex anchoring systems.

Geotechnical analysis plays a key role in determining whether deep foundations are necessary, particularly in areas prone to scour. The type and number of piers used also impacts the cost of the bridge relative to its span length.

A graph illustrating the cost benefits of piers related to bridge length.

Sustainability and Resilience Elements in Pedestrian Bridge Design

With a more volatile environment, sustainability and resilience are increasingly critical to pedestrian bridge design. Designers must consider environmental impacts, resilience to climate change, and seismic resilience where necessary. For waterway crossings, hydraulic and hydrologic modeling are essential to ensuring that the bridge can withstand extreme weather events and avoid damaging the surrounding ecosystem. There are a few aspects of bridge design where resilience is particularly relevant.

Stormwater and Drainage

Proper stormwater and drainage design is vital to prevent pollution and maintain the structural integrity of the bridge. Deck drains should be placed at regular intervals to keep the bridge watertight, and curbs should be installed on bridges crossing roads or highways to prevent water runoff. These measures help protect both the bridge and the environment.

Sustainable Materials and Energy Efficiency

The use of sustainable building materials and energy-efficient technologies is an important consideration in modern pedestrian bridge design. Recycled materials and energy-efficient lighting, such as LEDs, can reduce the environmental footprint of the bridge. Landscaping can also promote sustainability by supporting local ecosystems and enhancing the aesthetic appeal of the bridge.

Laporte Avenue Corridor and Bridge Improvements

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Take a closer look at the use of sustainable materials (including 97% recycled steel in bridge structures) as part of multimodal improvements to a corridor in Fort Collins, Colorado.

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Mitigation of Waterway Impact

When a pedestrian bridge crosses a waterway, special attention must be given to minimizing its impact on the stream and surrounding wetlands. Regulatory requirements often dictate freeboard levels and the number of piers allowed in the water. Designers must also consider fish passage and scour protection to preserve the natural flow and health of the waterway.

Aesthetic Elements in Pedestrian Bridge Design

While functionality and resilience are paramount, sometimes there is great value – particularly as part of a system of brides – in designing a pedestrian bridge that makes a statement. As integral components of the community, aesthetics can play a pivotal role in an area’s growth. A well-designed pedestrian bridge can become a landmark or gateway, enhancing the community’s identity and appeal. While purely functional bridges are often more cost-effective, investing in aesthetically pleasing features can add long-term value to the community.

The opportunity to consider aesthetics isn’t exclusive to grand design choices. There are a wide range of ways where even small features can have a large, lasting impact.

Bridge System Type

The type of bridge system chosen can greatly influence its aesthetic appeal. Beam and truss bridges are generally more functional, while arch, cable-stay, and suspension bridges offer greater creative freedom, allowing designers to create iconic structures that stand out.

Willapa Hills Trail Bridges

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Take a closer look at how after an extreme weather event, multiple pedestrian bridge designs are used to add resilience and safety to a trail system in the Pacific Northwest.

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Bridge Railing

Bridge railings are another element where functionality meets aesthetics. While they primarily serve to protect pedestrians and cyclists, railings can also be designed to enhance the visual appeal of the bridge. In urban or high-risk areas, railings are often higher and more enclosed for safety, whereas in rural areas, simpler designs may suffice. Historical railing systems can be preserved or replicated to maintain the cultural heritage of the area.

Bridge Lighting

Bridge lighting serves both functional and aesthetic purposes. It provides safety for users at night and deters vandalism, while also highlighting the bridge as a visual landmark. LED lighting has revolutionized bridge design, offering energy efficiency, reduced maintenance, and a wide range of color options. The right lighting can transform a pedestrian bridge into a striking feature of the nighttime landscape.

Taking a Multidisciplinary Approach to Pedestrian Bridge Design

Just as one community differs from the next, so do the pedestrian bridges that enhance their connectivity. With a considered process and collaborative approach combing the art and science of each project, the variety of design solutions available offer several paths to both meeting functional goals and making a statement for the community.

As a fixture of infrastructure designed to last decades, pedestrian bridges are created with an eye on the future and resilience in mind. Throughout the design process, input from a multidisciplinary team of engineers, planners, and architects is essential to creating landmark bridge design that maximizes the benefits of these public assets for generations to come.

See our Pedestrian Bridge Work

Eight Projects Recognized at 2024 DJC Oregon Awards

In recognizing some of the Pacific Northwest’s most impactful projects, DJC Oregon hosted its annual awards event. Among the ‘Top Projects’ for 2024 were eight from Otak, and our teams were in attendance for the honor.

Images of Otak teams at the 2024 DJC Awards event.
Left: Margaret Steinhilber, Martin Munguia, and Matt Neish with the award for the Hardeson Campus Service & Operations Building; Right: Ralph Mocerino, Nick Brown, Mike Day, Kathy Kianunis, Martin Munguia, Matt Neish, and Brian Hardebeck sit together at the event

The collective celebration of industry excellence covered a wide range of project types and included the selection of a ‘Project of the Year’ from the year’s winners. There was also a new award for ‘Subcontractor of the Year’ as well as ‘People’s Choice’.

Adding to our list of award-winning work, more detail into those eight Otak projects can be found below.

 

Hardeson Campus Service & Operations BuildingInterior image of the Hardeson Campus Service and Operations Building.

Representing a unique opportunity for adaptive reuse design, this project converted a two-story concrete tilt panel office building into an operations hub for the busy transportation organization, Community Transit.

Take a closer look at how this multidisciplinary effort between Otak architectural, structural, civil, and landscape teams revitalized this existing building with holistic improvements that place an emphasis on employee wellness.

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US 197: The Dalles BridgeCrew at work during the deck replacement of the Dalles Bridge along US 197.

Originally constructed in 1953, the deck of the steel-truss-cantilever Dalles Bridge on U.S. 197 had degraded to the point of needing to be replaced. Safety improvements to this vital transportation connection over the Colombia River utilized accelerated bridge construction techniques to avoid long term closure and disruption to regional commerce.

See how the Otak structural and construction management teams were part of a unique hybrid management system to efficiently complete this work.

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Littell Bridge: Willapa Hills Trail BridgesAerial image of the Littell Bridge as part of the Willapa Hills Trail Bridges project.

One of three bridges creating safe pedestrian passage along the Willapa Hills Trail system, the Littell Bridge addresses a previously dangerous at-grade crossing with SR 6. The 250-foot, sinuous bridge provides a final link in the western 27 miles of the trail.

Check out how Otak’s structural engineering and environmental teams combined to add safety and resilience to these trail crossings.

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Art Rutkin Elementary School: Tigard Tualatin School Bond ProgramInterior image of the library within Art Rutkin Elementary School.

As part of broader improvements to the Tigard Tualatin School district from a successful bond program, the new Art Rutkin Elementary School adds 75,000 square-feet of space for the community’s students.

Learn more about how the district, with Otak as owner’s representative, implemented technology upgrades and new sustainable features across its growing facilities.

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Monmouth City HallExterior view of the entrance to Monmouth City Hall.

After nearly a century of service, Monmouth City Hall would be replaced with a design focused on sustainability, safety, and operational efficiency.

Read more into how the Otak owner’s representative team joined the project to resolve cost issues while initiating a highly collaborative value engineering process.

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Nestucca Valley High School Career Technical Education CenterInterior view of workspace as part of the Nestucca Valley High School Career Technical Education Center.

In addressing the gap in diverse and accessible education opportunities for youth faced by many rural areas, the Nestucca Valley High School Career Technical Education (CTE) Center was developed as part of a school bond program for the communities of Coastal Oregon.

Get a more complete view of how as owner’s representative, Otak helped guide to completion the flexible design of a facility that will provide long-lasting benefits to the surrounding community.

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Waterleaf Affordable Housing BuildingExterior view of the Waterleaf Building and affordable housing project.

With a unique shared post-tension podium deck, the BRIDGE Waterleaf Building adds 178 affordable housing units to the River Place neighborhood of Portland, Oregon.

Take a more in-depth look at the Otak owner’s representative team guided this project through a number of challenges to make this community-focused building a reality.

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Multnomah County Library Operations Center

Rendering of the Multnomah County Library Operations Center.

In a major transformation across its facilities, Multnomah County Library is expanding spaces and upgrading technology to benefit the community through a capital bond program.

See how the $380 million bond program is being applied to these public assets with overall program management from Otak.

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Welcoming New Leadership and Elevating Internal Experts to Propel Rocky Mountain Regional Success

We’re happy to announce the appointment of multiple key leadership roles in our Colorado offices. With new and familiar faces, these individuals will focus on advancing our structural and transportation work as well as the multidisciplinary practice as a whole.

“We’re thrilled to enter this new phase of growth in Colorado. Under the guidance of three outstanding leaders, Otak will continue to expand, innovate, and excel in the Colorado market by delivering exceptional client service.”

– Raul Aviles Jr., CEO of Otak

Read on to learn more about the people who aim to expand the positive impact of our work in the Rocky Mountain Region.

Henry Alaman, Regional Director

Headshot of Henry Alaman.

Heading up the team as the new Colorado Regional Director is Henry Alaman, who brings a wealth of experience and a proven track record of leadership to his new role.

With over 30 years of experience, Henry Alaman is a seasoned professional with demonstrated expertise in organizational development, leadership, project management, and business development. Celebrating four years with Otak, Henry has played a pivotal role in the growth and success of the firm’s Project Management and Construction Management (PMCM) division. He has been instrumental in leading key initiatives such as recruitment, onboarding optimization, training programs, and incentive implementations, which have contributed to Otak’s ability to recruit and retain top talent in the industry.

In his own words, Henry expresses gratitude for the support from his colleagues at Otak, stating, “It’s been a humbling experience to be surrounded and supported by such a talented and engaged staff. They have been the collaborative driving force in the progress we’ve made.”

 

Todd Kelley, Bridges & Structures Business Unit Leader

Headshot of Todd Kelley.

Bringing fresh eyes and ideas to Otak’s bridges and structures group, Todd has over 17 years of experience in structural engineering design, including: railroad bridges, highway bridges, industrial structures, bridge inspections, and ratings.

With strong analytical and communication skills, his background also includes project and staff management. Todd received his Bachelor of Science in Civil Engineering and a Master of Science in Structural Engineering from the Southern Illinois University. He is a licensed professional engineer in Colorado, Missouri, Washington, Idaho, and California, and a licensed structural engineer in Illinois. Prior to joining Otak, Todd worked for American Rail Engineers in Denver, as General Director of Bridge Design.

Todd expresses his excitement to lead at Otak: “In taking this opportunity at Otak, I was drawn to the experienced people and exciting projects. I’ve found my team to be technically savvy, providing a great foundation for the growth of our group. With plenty of diverse and unique structures, Otak’s approach to projects fits my experience – and where I’d like it to go – perfectly.”

 

Kevin Dooley, Transportation & Infrastructure Business Unit Leader

Headshot of Kevin Dooley

Kevin has been with Otak’s Louisville office since 2017 as Transportation Project Manager, contributing his talents to much of the region’s major transportation work including: City of Boulder’s 30th & Colorado Underpass, City of Aspen’s Paepcke Transit Hub, Eagle County’s Eagle Valley Trail, City of Longmont’s Coffman Street Mobility Improvements, and the SH119 (Diagonal) Reconstruction project.

Confirming his confidence in the regional team, Kevin shares, “We currently have the best group of T&I staff that I have seen in my time here. From mentorship and training to the work itself, everyone is already adept at working together very well. This has us set up to provide opportunities for everyone to grow professionally while taking on new technical and managerial challenges.”

Building on more than 17 years of civil engineering experience, including the design and management of complex transportation and civil improvement projects, Kevin’s expertise spans roadway and trail design, drainage, and utility design of local agencies and federally funded projects. His field experience gives him valuable insight into the complete project delivery cycle and his hands-on approach to management and design ensures that projects will have an accurate and reliable set of construction documents. Kevin also participates in Otak’s sustainability leadership group, assisting with green initiatives in the company’s practice areas and training.

 

“The Colorado Region leadership has never been as strong and engaged as the team we have in place now… Their focus on client care, high quality, timely service delivery, solving for our clients, and mentorship skills makes me confident in their ability to develop the best team possible in our market.”

– Scott Dreher, COO of Otak

 

Otak is excited to continue generating momentum for our work in the Rocky Mountain region with the addition and promotion of top talent. The company is eager to see Henry, Todd, and Kevin thrive as leaders and develop project work and partnerships with key regional clients.

Green Line – Swift Bus Rapid Transit

In expanding access to Washington State’s first Swift bus rapid transit (BRT) system, the Green Line adds greater connectivity to the region across 33 station sites. Otak led design and permitting while also providing construction engineering support for new transit platforms, the installation of custom shelters, and other associated transit improvements.

Designing Expanded Public Transit Infrastructure while Improving Corridor Safety

Spanning 12 miles, the Community Transit Green Line BRT extends from the Canyon Park Park-and-Ride on I-405 to the new Seaway Transit Center, located across from the Boeing Everett site. The project also included construction of roadway and signal improvements at three locations to improve transit reliability and safety in the corridor, including widening improvements for queue bypass lanes. Roadway improvements required retaining walls to minimize property and environmental impacts at several locations, including the relocation and improvement of the Interurban Trail. Otak’s efforts included coordination and obtaining site and shelter design approvals from WSDOT, Snohomish County, and the cities of Bothell, Mill Creek, and Everett; preparation of NEPA documentation, wetland mitigation design and permitting, preparation of PS&E to meet FTA/FHWA requirements, utility coordination, and ADA compliance.

Yellowstone National Park Canyon Rim Trails and Overlooks

To enhance the visitor experience and create future stewards of Yellowstone National Park, this much-needed restoration made improvements to the deteriorating north and south rim trails and overlooks, which wrap the Canyon Rim from Inspiration Point to Artist Point.

Restoring Historic National Park Features and Enhancing Visitor Experiences

The multi-phase project included design of a new trail system and overlooks as well as the rehabilitation of historic elements at Inspiration Point. In enhancing the Canyon Rim Trail system, the design also created new trails, overlooks, and parking improvements at the Brink of the Upper Falls and Uncle Tom’s Point. The design materials and features reflect the rustic design style synonymous with Yellowstone National Park. Design solutions include re-routing trails away from dangerous areas and installing stone and boulder barriers; connecting historic overlooks with new walkways; creating safe, accessible viewing areas with new wayfinding and informational signage; constructing new visitor pavilions and kiosks with peeled logs and stone masonry columns; and using natural materials to integrate the infrastructure into the spires and canyon cliffs.