The 55-story core-and-shell Class-A office tower and half-acre Riverwalk park plaza is built on one of the last available pieces of riverside real estate in downtown Chicago, and is the tallest office tower built in the city in the past 30 years.

The project was constructed using an innovative embedded steel truss system, designed by the team during preconstruction, which allowed vertical construction to commence much earlier than with a conventional design. The team also seamlessly accommodated the addition of two mid-level floors to the structure by the owner after steel construction had begun.

The team used virtual modeling for clash detection with MEPFP trades to ensure the most efficient use of space on each floor. The square footage saved through this room sizing was converted into leasable space for the owner.

Historic metal panels were saved during demolition of the old building on site and thoughtfully integrated into the project’s modern design to seamlessly blend Chicago’s past and present.

The $354 million project was completed a month early, with an excellent safety record and 3% under budget.

Constructed on one of the last available pieces of riverside real estate in Chicago, 110 North Wacker Drive is a new icon in the city’s downtown skyline. Completed a month early, with an excellent safety record and 3% under budget, the successful delivery of the 55-story core-and-shell Class-A office tower, half-acre Riverwalk park plaza, and two-story below-grade parking structure is a testament to the project team’s attention to detail at every level. From the building’s embedded steel truss system and carefully placed MEPFP systems to the historic metal panels that grace the Riverwalk, the latest virtual modeling technology and a system of mockups ensured every aspect of the structure maximized function and fulfilled the aesthetic intention of the design. Constructed with local subcontractors, the project was completed with minimal disruption to the busy neighborhood, and provides the lasting benefit of welcoming public space for the community along the Chicago waterfront.

110 North Wacker was designed to be the crown jewel of office space along the Chicago River. The Clark team worked with Riverside Investment & Development (Riverside, the owner) and Goettsch Partners (the designer) from concept design through design completion to fully capture the client’s and designer’s vision.

Leveraging Virtual Modeling Tools

To achieve the project’s quality requirements, the Clark team leveraged several tools, including virtual modeling (VDC) of key public spaces. The team used the building model for clash detection with MEPFP trades and real-time input on equipment location during the preconstruction phase. This process ensured the most efficient use of space on each floor by right-sizing the mechanical and electrical rooms on office floors. The square footage saved through this room sizing was converted into leasable space for the owner.

In addition to using the building model for MEPFP pre-planning and design, the steel, curtain wall, and elevator subcontractors created and coordinated their work through 3D models to facilitate a smooth construction process. The project team collaborated with curtain wall, lobby glass cable-wall, and structural steel trades in a design-assist capacity to facilitate a smooth transition from the preconstruction and design phases into construction.

Once construction was underway, the Clark team used StructionSite to take 3D photos of the project daily. These images played a critical role in the quality control process by providing Riverside and Goettsch Partners with an accurate picture of the team’s progress on-site to ensure that work put in place adhered to the project’s original design vision. The team conducted weekly design review meetings to evaluate the building’s virtual model and resolve any design coordination issues with both the owner and the design team.

Verifying Details with Mockups

Clark also constructed several off-site and on-site mockups, including multiple curtain wall and cable-wall mockups at facilities in the United States and Europe as well as stone element mockups of the lobby, elevator cabs, and plaza located in Italy. These mockups helped the team identify material tie-in issues, establish the best material installation process, and set quality standards for key work elements. In addition, the team also developed an on-site bathroom mockup to resolve potential design and coordination challenges ahead of time and ensure a high-quality end product. All the mockups for 110 North Wacker, both visual and performance-based, allowed the design team to refine their ideas for the project, ensuring that the building’s aesthetics met the design and building performance goals. Through these detailed efforts, the team adjusted colors, materials, and installation methods to achieve a structure of the highest quality for the client.

Incorporating Historic Metal Panels

Before the old General Growth Properties (GGP) building was demolished on site to make way for the new building, a historical landmark review by the IHPA and the U.S. Army Corps of Engineers determined several existing metal panels from the GGP building should be removed and reincorporated into 110 North Wacker’s facade. Adding these historic panels to the design created both aesthetic and building performance challenges. Clark successfully removed these elements before demolition and discovered asbestos during the removal process. Working with key subcontractors, the team developed a remediation plan that retained the panels’ historical integrity and ensured the new facade feature could proceed as planned. Through Goettsch Partners’ creative redesign of the Riverwalk, these historic metal panels were thoughtfully integrated into the project’s modern design to seamlessly blend Chicago’s past and present.

Devising an Innovative Steel Truss System

110 North Wacker boasts several innovative structural steel conditions: the lower-level foundation wall, outriggers, a belt truss system, and a sawtooth shape at the west face of the structure. Most notably, the east foundation wall, spanning from the Lower Level 2 concrete slab-on-grade to Upper Wacker Drive, was constructed with an embedded steel truss system. The team designed this solution during preconstruction, which allowed Clark to commence vertical construction with structural steel much earlier than a conventional design. With this system, Clark was able to construct the structural deck at the lobby level and proceed vertically without pouring concrete for the Lower Level 2 slab-on-grade or the Lower Level 1 cast-in-place concrete deck. Coordination and teamwork amongst Clark, Goettsch Partners, and Thornton Tomasetti were critical to achieving this time-saving solution while maintaining the integrity of the design.

Adding Two Stories to the Structure

A key design challenge occurred when Riverside added two mid-level floors to the structure after Clark had begun constructing steel at level five. This change, made without an extension of the schedule, created several conflicts with previously designed and coordinated scopes of work, including MEPFP, curtain wall, elevators, structural steel, and concrete. Clark worked hand-in-hand with subcontractors and suppliers to redesign and procure all the materials needed to continue the project, on schedule, within weeks. The team’s herculean effort allowed Riverside to add 70,000 leasable square feet without sacrificing the building’s design aesthetic or performance.

Ultimately, the success of 110 North Wacker is due to the team’s attention to detail at all levels, from major structural components such as the embedded streel truss system to the elegant incorporation of the historic panels. From preconstruction through closeout, the team’s collaboration and meticulous attention to both the aesthetics and function of each component resulted in a building that reflects quality at all levels, inside and out.

110 North Wacker features the quality craftsmanship of many local Chicago-area subcontractors. Twenty-two out of the thirty subcontractors employed on the project were based out of Chicago or surrounding suburbs, comprising 73% of the total subcontractors on the job. In addition to benefitting the local workforce, the project served as a local training opportunity as the tallest office tower built in Chicago in 30 years. Disruption to the busy neighborhood was minimized during construction, and the completed project provides the lasting benefit of welcoming public space along the Chicago waterfront.

Hosting Local Educational Opportunities and Community Service Efforts

On September 27, 2019 the 110 North Wacker Drive project hosted the AISC Steel Day event for Chicago. Steel Day is the annual celebration of the structural steel industry, sponsored by the American Institute of Steel Construction and hosted by its members and partners. The event enables AEC professionals, faculty, students and the public to see firsthand how the U.S. structural steel industry works to build buildings and bridges. The 110 North Wacker Drive project team showcased the 56-story core and shell office building through a presentation segment followed by a site tour for over 50 local attendees.

The 110 North Wacker Drive team also participated in several community efforts throughout construction, including park clean-ups, blood drives, and packing of lunches for homeless shelters.

Minimizing Neighborhood Disruption During Construction

Sensitive to the fact that North Wacker is a notoriously congested area with an inordinate amount of truck traffic servicing commercial buildings with loading docks, the project team used the lower Wacker Drive and the river to its functional advantage during demolition to minimize impact on the surrounding community. Material barges, catch decks, and heavy machinery were utilized to clear the debris safely and efficiently from the dense urban site. Nearly 17,000 tons of material was removed via trucks and barges while reducing both the amount of congestion in the neighborhood and environmental impact.

The team also re-supported an existing seawall in proximity to the building’s deep foundations. The team’s innovative approach allowed them to utilize the re-supported seawall as a dock or mooring point for barges throughout construction. This access to the river as a staging area, work area, and delivery point allowed the team to perform additional excavation and steel erection from the Chicago River, reducing the impact to the neighborhood.

Enhancing Public Space Along the Riverfront

The landscaped, covered, 45-foot-wide riverfront promenade connects two important downtown pedestrian paths and a pocket park at the north. With the building hovering 55 feet overhead, supported by nine tapered columns that meet in three structural nodes, the walkway features an unobstructed river view, offering roughly 22,000 square feet of combined public space. In combination with other space, the site is 50% open and publicly accessible at grade, and provides welcoming outdoor areas for the community to enjoy the natural asset of the river.

With just under 1.4 million worker hours clocked during the construction of 110 North Wacker, the team completed the project with a total recordable incident rate of 1.9. This success was due to stringent safety measures governing work at both the corporate and jobsite levels designed to keep teams safe each day.

Key tenets of Clark’s corporate safety program that were utilized on the project include:

Site-Specific Safety Orientation: All jobsite personnel and visitors complete the site-specific safety orientation before entering the project. All oriented personnel receive a numbered sticker for their helmet so we may easily identify any worker onsite not oriented (and provide a proper orientation).

Job-Wide Safety Meetings: At a minimum, each project has a monthly safety meeting to ensure every worker is kept apprised of changing site conditions, upcoming work, and jobsite safety performance. Many projects deem it appropriate to hold these stand downs weekly based upon the amount of work (and subsequent change of conditions) occurring during the peak of construction.

Toolbox Talks: All crews conduct a weekly safety training pertinent to the week’s work.

Project Safety Committee: Safety representatives from each contractor gather weekly to review the safety program including recent successes, focus areas, and opportunities for improvement.

Subcontractor Meetings: Safety is the first topic of discussion each meeting with our trade partners.

Safety Site Assessment Walks: Each member of the project management and field supervisory personnel are required to complete safety site assessment walks at various intervals, as mandated by Clark’s Corporate Safety and Health Policy.

In addition, Clark took every precaution to minimize the risk of infection on the jobsite and implemented these and other preventative strategies as part of our overall COVID-19 management plan:

Reinforced the importance of physical/social distancing, hand hygiene, and respiratory etiquette with the workforce.

Educated workforce on the symptoms of COVID-19 and required individuals who are sick to stay home

Performed cleaning of frequently touched surfaces, portable toilets, and shared tools on the site

Implemented measures for social distancing including spreading out work as much as possible, deploying a rotational telework plan for management staff, and encouraging workforce to minimize close contact

Required face coverings for everyone on the jobsite and in our offices

Protocols were also established in accordance with CDC and OSHA recommendations to address a confirmed case of COVID-19 on the jobsite or in an office, including isolating the individual, investigating and informing those who may be impacted, and disinfecting impacted areas. Clark remained fully committed to operating in accordance with the guidelines set forth by national industry and health authorities and local health agencies.

Through excellence in project management and on-site super vision, the project team delivered 110 North Wacker one month ahead of schedule while maintaining a safe work environment.

Addressing Site Specific Safety Conditions

With a site adjacent to the Chicago River, the project contended with heavy boat traffic within close proximity of construction from April to October. To ensure that boaters were aware of possible overhead work/hazards, overhead work signs were posted along the river wall. In addition, sailboat traffic on Wednesdays and Saturdays necessitated a notification system which paused work on construction trades working along the western edge of the building while sailboats were directly below. Craftworkers stood along the river wall to discourage boaters from sitting against the wall. Pedestrians were protected by an overhead canopy that surrounded the project on the other three sides. When cranes picked items over the top of the canopy, pedestrians were stopped until the pick was completed.

▪ The Indoor Track & Field Facility at Gately Park is a world class indoor track and field complex, putting Chicago on the map for collegiate and international competitions. The facility includes the 12th hydraulically banked track constructed in the United States. This gives the option for the curves at the end of the track to lay flat or be inclined depending on the competition that is being held. Additionally, this facility meets or exceeds NCAA standards for design and is certified by World Athletics, the governing body for international competition (formally IAAF), thus providing the ability to recognize records set during competitions.
▪ The project served as a model of collaboration and flexibility between public and private entities, as well as non-profit organizations, with the goal of providing spaces that are not only significant in their stated functionality, but also enhancing the quality of life for the community and providing opportunities for disadvantaged firms to participate in the design and construction of the project. With ownership by the Chicago Park District and the partnership with After School Matters, the facility provides community space to the residents of the Pullman neighborhood including a flexible design that allows the facility to host recreational sports for the surrounding community.
▪ A hallmark of the project was its approach to diversity and inclusion at all levels of construction of the project. At the general contracting level, McHugh Construction partnered with BOWA Construction, a recognized Chicago-based minority owned contractor, to put together a team to manage the overall construction of the project. The project achieved over 40% MBE participation and over 9% WBE participation and had over 430 minority tradespeople that worked on the project.
▪ The project’s design harkens back to the classic structures in the surrounding Pullman neighborhood while incorporating modern touches. The project façade consists of a combination of brick veneer, precast concrete, and large storefront/curtainwall windows. Behind that façade are some unique elements, including a state of the art timing system with reverse angle camera coverage and power actuated windows tied into the Building Automation System significantly reducing the required capacity of Mechanical Ventilation. The building structure consists of a combination of traditional steel frame for the office and classroom spaces, cast-in-place concrete slabs and bleacher sections, and oversize custom fabricated trusses for the Fieldhouse section, all of which were procured and coordinated seamlessly. The building HVAC system features a highly efficient variable refrigerant flow system, providing increased energy efficiency over other similar facilities.
▪ The project was designed around the USGBC’s LEED Version 4 BD+C standards and as such incorporates a number of environmental and energy efficiency standards that exceed building code requirements and enhancing the quality of the space for occupants. Once the certification process is complete, the project is anticipated to receive LEED Certification. Environmentally friendly features include low flow water fixtures; enhanced energy efficiency exceeding code requirements through a combination of more efficient equipment/systems and increased thermal performance on the building envelope; recycled materials and regionally sourced products; and increased ventilation and air quality with user safety and comfort in mind.

The Chicago Park District’s new Indoor Track & Field Center at Gately Park is a world class sports complex and year-round community center for wellness, culture and after-school programming. The facility enhances recreational and competitive event opportunities in Chicago’s Pullman and neighboring communities and features the area’s first hydraulically banked 200-meter track inside a multi-use 125,000 SF Fieldhouse.

The facility also contains 22,000 SF of dedicated space for After School Matters, including a dance and exercise studio, full culinary teaching kitchen, gathering/performance space, rooftop deck and garden, and multi-purpose labs for art, science, and technology. Community offerings include a fitness center, multipurpose rooms that service a variety of activities, and a kitchenette available for wellness programming and park camps. The building can easily host 700+ patrons for non-track and field events and will serve the Park District and community.

The McHugh/BOWA Joint Venture (MBJV) team leveraged the latest technology, including 3-D modeling, to create operational and cost efficiencies throughout construction. This technology enabled real-time communication between and among construction managers, subcontractors, and vendors, which was critical in addressing and resolving issues without costly delays. 3-D models of the structure were also utilized during field team training, providing crews a complete look into the construction and addressing questions or concerns in advance.

Construction required months of detailed planning by dozens of specialized teams to successfully ensure the safety and quality of tasks. This included fabrication, assembly, and erection of the (6) 252’ x 20’ deep barrel-vaulted roof trusses, each weighing a total of 120 tons and responsible for supporting the entire roof of the Fieldhouse. The trusses were pre-assembled to the maximum extent allowed for delivery at the steel fabricators shop, shipped to the site in (41) pieces, final built/assembled on-site, and then lifted into place at the site a 330-ton crane.

The specialized hydraulic track system required skilled craftsmen to assemble the complicated system of jacks and pumps within the pits at both ends of the track, as well as the supporting construction need to be built to incredibly tight tolerances to allow for the system to be installed and function properly. The process involved controlling the curved concrete forming the pit walls under the hydraulic section of the track along with extensive measurement and verification of the necessary super flat slab. MBJV team meticulously surveyed and verified the framing and final product to ensure the highest quality of construction. Provided by Kiefer/Mondo, a worldwide leader and innovator in indoor tracks, The track system has 6 preset banking angles (depending on the length of race/speed of runners). The track was fabricated and placed to strict tolerances by a team of Owner certified installers. Supervisors from the manufacturer’s factory in Italy were sent to monitor the installation and commission the system to ensure it received the IAAF certification that allows for record times run on the track to stand.

The exterior of the building is comprised of unique precast architectural panels that include brick as well as two colors of concrete. Within the profile of the panels are architectural fins that project around the building. To have the fins continue seamlessly around the 90-degree corners of the field house, precast installation required the MBJV team to closely monitor tolerances and diligently coordinate multiple trades on the busy jobsite. The use of precast concrete wall materials promotes the safety of the building occupants, as well as the use of bullet-resistant drywall behind the façade materials within specific areas of the facility.

For the construction to proceed smoothly, the MBJV team worked with the Design Team to develop a better solution for the structure supporting the bleachers in the Fieldhouse. The original design called for precast bleacher seating to be installed in this section, but after sequencing reviews of the structural steel and precast enclosure, the MBJV team realized this would be a costly, if not impossible way to construct this portion of the project. Working with Williams Architects and the Structural Engineer, the MBJV team determined that this section of the Fieldhouse could be constructed out of cast-in-place concrete while maintaining cost and schedule.

The project is intended to achieve LEED Certification and as such, includes a number of enhanced sustainability features including low flow fixtures and locally sourced materials. Of note are the features that improved energy performance within the facility, including the use of high-performance exterior glazing, energy efficient LED lighting, well-insulated exterior wall construction, and a variable refrigerant flow (VRF) mechanical system that reduces the cost of operating the facility. Also, indoor air quality was a focus of the facility design, and the project includes the use of low VOC materials, increased ability to control occupant comfort, and a unique motor-actuated operable glass window system for the Fieldhouse that allows for fresh air to be incorporated into the facility.

To ensure quality of installation throughout the entire project, internal inspections by the McHugh Quality Assurance Team were conducted during every phase of construction. The MBJV team’s Quality Manager, independent testing agencies and Williams Architects proactively inspected work regularly throughout the duration of the project. Additionally, the Park District’s staff inspector reviewed the quality of work being installed daily. The MBJV team conducted preinstallation meetings, reviewed constructability and compatibility of all materials, monitored concrete, windows, rebar, structural engineering requirements and finishes, and documented and resolved quality issues early to ensure the highest quality product.

Field team training was critical to assuring quality control on the worksite, and significant resources were allocated for training prior to the start of each new construction activity. All crewmembers were trained on the team’s quality assurance standards and encouraged to participate in quality assurance audits on the worksite. QA specifications were available for access by all crew via a web-based library, and they were encouraged to play an active role during inspections by accessing and commenting on drawings, specifications, and reports.

▪ Chicago Park District CEO Michael Kelly described the importance of the facility as follows, “This state-of-the-art facility will provide unprecedented recreational and competitive opportunities in Roseland, Pullman and neighboring communities. In addition to cultivating young athletes and supporting local programming, this indoor track and field [facility] will have the capacity to attract regional events, bringing economic benefits to the area.”
▪ More than 90% of the programs now offered at the facility are aligned with youth skill development in areas of concentration: shot put, long jump, middle and long distance, high jump, hurdles, sprints and relays.
▪ Athletes from across the city have an opportunity to register for “open” track and field programs to test out the hydraulic and Mondo surface, along with the world-class throwing cage, timing system, video board and jump pits.
▪ An educational initiative is being developed with USA Track & Field to encourage local and Chicago Park District track coaches to continue their professional development through curriculum training and certification. The partnership with After School Matters will ensure that local youth are exposed to additional instructors and resources.
▪ Several local universities have agreements for scheduled practices and collegiate competitions, while other college and high school programs have expressed interest and plan to visit the facility for practice in the future.
▪ A variety of classes, clinics and programs were offered this summer and fall 2020 and are anticipated to continue in spring 2021 following COVID-19 health guidelines. Offerings include Advanced Track and Field, After School Programming, Basketball, High Jump Techniques, Introduction to Hurdles, Shot Put, Summer Camps, Relays and Jumps, Line Dance, Middle Distance Training, Cardio Roll and Tone and much more.
▪ The After School Matters program offered at the facility includes a dance and exercise studio, full culinary teaching kitchen, gathering/performance space, rooftop deck and garden, and multi-purpose labs for art, science and technology.
▪ The project featured over 40 different subcontractors and vendors and required the employment of over 1000 construction professionals representing more than 25 different union trades and locals to complete the project. Beyond the impact to the construction and operational people associated with the facility, the impact to the community will extend well beyond to the adjacent neighborhoods of Burnside, Chatham, Pullman, and Roseland. Large events held at the facility will bring much needed commerce to the area and as a community hub, dozens of Chicago Park District and After School Matters programs will be held every month.

All project stakeholders agreed that getting crewmembers home safely every day was the chief priority. The project, which was serviced by over 1000 construction professionals, was completed with zero time lost and recordable injuries.

The project presented a unique safety challenge for several reasons: assembling and erecting the 252’ x 20’ deep barrel vaulted roof trusses took months of detailed planning by dozens of specialized teams and required close coordination on the busy jobsite to ensure the safety of everyone involved. The project team not only had to think about the logistics involved with staging the (41) total pieces for the trusses, but also for allocating space for the final assembly. A detailed plan for the installation sequence of the trusses was implemented with areas planned for the crane pathway through the center of the building footprint and laydown of the completed trusses alongside the crane path. The team also had to take into consideration the requirements for providing a stable structural base as a crane pad that required. A similar approach was employed for the erection of the architectural precast exterior.

For overall safety planning, our construction management team worked closely with neighborhood officials to adjust traffic patterns and create a safer environment for field crew, pedestrians, and vehicle traffic. During construction, a full-time safety manager was always on site to ensure adherence to the teams’ strict safety standards. Work crews began each day with a Take 5 for Safety prior to commencing work. A Take 5 is a snapshot of the tasks for the day, the hazards that may be present, and the mitigation strategies put forward to prevent those hazards from occurring. The foreman for the crew led these meetings and drove home that safety was the #1 priority of the project. Crews were required to wear high-visibility, level two safety apparel as well as attend ‘stretch and flex’ sessions to ensure they were prepared for the project’s physical demands each day.

Despite the COVID-19 pandemic, the MBJV team was able to implement new safety procedures to allow for the project construction to proceed as scheduled. The newly established safety protocols, put in place in early March 2020, included all on-site personnel completing a daily wellness audit, temperature checks, wearing face coverings at all times on site, increased handwashing and sanitizing of the project site, and always maintaining social distancing. To review these new protocols, the team conducted (3) safety stand-downs to train and clearly explain the new working requirements. This allowed for construction to proceed without any impact to the completion schedule.