To support the Minnesota Department of Transportation’s (MnDOT) Twin Ports Interchange (TPI) project in Duluth, Barr provided advanced geotechnical engineering services to address challenging subsurface conditions. The project replaced aging elevated roadways and infrastructure with embankment-supported concrete pavement and seven bridges, aiming to enhance traffic safety and increase freight capacity.
The site, adjacent to Lake Superior and near the mouth of the St. Louis River, features soft, compressible soils, shallow groundwater, and decades of industrial fill. To mitigate settlement risk, Barr designed a column-supported embankment (CSE) system covering an area of over 13 acres to support the interchange. This system features an array of over 8,200 vertical columns with caps supporting a load transfer platform and lateral reinforcement to stabilize the new embankments, which range in height from 5 to 35 feet.
Barr and our subconsultant developed a detailed 3D subsurface model and performed advanced geotechnical numerical modeling analyses using FLAC3D to simulate soil-structure interactions, evaluate embankment settlement, and optimize the ground improvement design. The models formed the basis of design for the ground improvement system. Our team also supported MnDOT’s field test program during design, calibrating numerical models with real-world data and refining installation methods.
The construction of a CSE system requires site-specific load testing and specialized geotechnical instrumentation to confirm that the system is installed and performs as intended. Barr recommended load testing of the columns to confirm installation and recommended geotechnical instrumentation to monitor the performance of the CSE components. Instrumentation included strain gages in columns, strain gages on lateral reinforcement, horizontal and vertical in-place inclinometers with accelerometer sensors, settlement plates, piezometers, and earth pressure cells. Barr also provided structural monitoring of the existing traffic-bearing bridges and the newly constructed bridge substructures, which were susceptible to adverse movements from CSE construction.
The project was completed in October 2025 through MnDOT’s Construction Manager/General Contractor project delivery program.
To support Arizona’s clean energy goals and grid reliability, EDF power solutions North America (EDF) partnered with Arizona Public Service (APS) to develop and construct the Beehive Battery Energy Storage System (BESS)—a 250 MW/1,000 MWh facility located in Maricopa County, just north of Phoenix. The project is designed to store renewable energy and dispatch it during peak demand periods, helping APS meet its target of 100% carbon neutrality by 2050.
Geotechnical engineering services
EDF engaged Barr to conduct preliminary and design phase geotechnical investigations, informing foundation design and construction planning for the BESS, substation, roads, and transmission line alignment. The site’s location in the Sonoran Desert presented unique challenges, including variable subsurface conditions, potential geologic hazards, and difficult pile-driving environments due to the presence of cobbles and boulders.
We conducted a series of geotechnical borings, test pits, and pile load tests to assess the site for BESS foundation suitability. Geotechnical laboratory tests were completed to characterize soil stratigraphy and support geotechnical analysis and design recommendations. We also performed analytical testing to assess corrosion potential, thermal resistivity testing to support underground collection design, and electrical resistivity testing to support grounding design.
Based on our findings, we recommended foundations tailored to each infrastructure component. For the BESS, we evaluated both pre-drilled driven piles and precast concrete beam foundations. For the substation and transmission line, we provided design parameters for spread footings, drilled shafts, and direct embedment foundations.
Civil engineering services
Barr’s civil engineering services included an evaluation of public road conditions, an inventory of culverts and bridges, and a capacity analysis of these structures. These assessments were necessary because future deliveries of BESS components will be in oversized or overweight loads, requiring special considerations for equipment delivery during construction. With this data, EDF was able to select effective and reliable delivery routes for BESS components.
Barr’s services helped EDF and the construction contractor optimize foundation design, reduce construction risk, and provide for long-term performance of critical infrastructure. Our deliverables provided actionable guidance for the design team, supporting the successful development of a high-impact energy storage facility that advances a clean energy future and enhances grid stability.
The Walled Lake Branch of the Rouge River daylighting project restored an approximately 1,100-linear-foot stream reach that was enclosed in a large culvert to an open, free-flowing natural channel. This revitalized reach serves as the centerpiece of River Park, a new public space in the multi-use redevelopment of the historic Northville Downs horse racing facility.
In 2022, the developer of the Northville Downs project turned to Barr to design the new open river channel and to lead permitting of the river restoration and floodplain modification. Working with the development team, we developed early concepts for the daylighted reach based on natural stream channel design principles to help ensure long-term stability, ecological function, and aesthetic integration with the surrounding park. After an extensive public engagement process, we further developed those concepts into detailed designs that met community interests and were suitable for permitting and construction.
As an additional, practical benefit to the community, Barr developed the hydraulic design to modify the floodplain and contain up to the 500-year flood without increasing flood risk to adjacent properties. We led the permitting process with the Michigan Department of Environment, Great Lakes and Energy (EGLE) for regulated stream and floodplain activities and with the Federal Emergency Management Agency (FEMA) to remap the associated floodway and floodplain.
The stream daylighting and River Park construction were substantially completed in October 2025.
Planning a large solar array and battery energy storage system on over 600 acres of Navajo Nation Off-Reservation Trust Land, a confidential client looked to Barr for cultural resources consultation and a Class III pedestrian cultural resource survey. Our goals were to identify the project’s potential impacts on Historic Properties—cultural resources eligible for listing in the National Register of Historic Places (NRHP)—and determine actions necessary for the project’s compliance with the National Historic Preservation Act (NHPA), Section 106 (36 CFR 800).
Barr first conducted a Records Check and Literature Review of the New Mexico Cultural Resource Information System database to investigate any previous cultural resource surveys or recorded archaeological sites in the project area. We facilitated an additional records check of the Division of Conservation Archaeology at the Navajo Nation Heritage and Historic Preservation Department in Window Rock, Arizona. Through this research, we identified numerous cultural resources at the project site that might be eligible for NRHP listing as well as areas that had not been adequately surveyed.
With this information, Barr conducted a Class III pedestrian survey of the entire project area following fieldwork methods required by the Navajo Nation. We documented all cultural resources in the project area, including archaeological sites, Traditional Cultural Properties, and isolated occurrences (IOs)—non-structural remains of a single event or an assemblage of a limited number of artifacts. In total, we identified 46 archaeological sites and 137 IOs.
Barr assessed each of our findings for NRHP eligibility. In our final report, we documented our survey methods, eligibility determinations, and recommendations for minimizing disturbance to eligible or potentially eligible cultural resources. This report helped the client meet federal requirements under Section 106 of the NHPA and avoid adverse impacts to Historic Properties.
Kathryn Dam was an aging low-head concrete dam located on the Sheyenne River in Kathryn, North Dakota. The Barnes County Water Resource District was looking for options to remediate structural concerns and also eliminate the dangerous hydraulic roller that existed below the dam.
The district hired Barr as a subconsultant to its primary engineering consultant, Moore Engineering, Inc., to evaluate alternatives to repair, remove, or replace the dam. The project began with a feasibility study to analyze three alternatives: complete removal of the dam, replacement of the dam with rock-arch rapids, or placement of a rock wedge beneath the dam to mitigate dangerous recirculating currents below the dam. The district decided to replace the dam with rock-arch rapids.
Barr, in consultation with Moore, completed permitting, hydraulic modeling, final design, and preparation of construction documents for the rock-arch-rapids dam replacement. The project was constructed in winter 2020-2021; Barr provided periodic on-site construction support and assisted Moore with administering the project, which was partially funded through the North Dakota State Water Commission’s cost-share program.
The completed project eliminates the dangerous hydraulic roller beneath the dam, minimizes the need for future maintenance, mitigates erosion concerns on the banks downstream of the dam, offers fish passage through the structure, and provides recreational features for paddlers and anglers on the river.
Graphite One Inc. plans to develop the Graphite Creek Project, a graphite mine and mineral processing facility near Nome, Alaska. Barr completed an NI 43-101-compliant feasibility study, which incorporated data and information from other consultants, third-party laboratories, and Graphite One, and ultimately published a compliant technical report for the project. Part of Barr’s work involved designing a waste management facility (WMF) to store co-mingled tailings produced by the mill and waste rock (non-ore material) from the mine. The WMF’s primary objective is to safely store the material produced during mining operations while prioritizing progressive closure of the facility and minimizing operating and capital costs.
To support the design of the WMF, Barr completed geotechnical characterization and analysis of the site and performed material characterization for the filtered tailings produced by the pilot processing plant. Barr retained an expert seismologist consultant to perform site-specific probabilistic seismic hazard analysis (PSHA) and a deterministic seismic hazard analysis (DSHA). These analyses were based on a selected design earthquake to develop ground motion time histories for use in seismic deformation modeling.
Barr conducted a field investigation to assess and characterize foundation conditions. We performed seepage analysis, slope stability analysis, and deformation modeling using GeoStudio and FLAC to help evaluate constructability, long-term static stability conditions, consolidation processes, and seismic loading. We also performed advanced, critical state-based constitutive modeling for both static and seismic deformation modeling and liquefaction assessments. Conducting a sensitivity assessment helped us to model the potential transition of filtered tailings from unsaturated to saturated conditions and the associated impacts with respect to liquefaction susceptibility.
The Copper Peak ski jump is the world’s tallest artificial ski jump superstructure, towering 26 stories over the hilly forests of Michigan’s Upper Peninsula. Three decades after hosting its last competition, the volunteer board of Copper Peak, Inc. is modernizing its facility to meet current International Ski Federation (FIS) standards. As designed, the renovated Copper Peak ski jump will be the only FIS-designated “giant hill” for international training and events and the world’s largest FIS-certified ski jump used year-round.
We’ve partnered with the board in this ambitious effort to bring this facility to the world stage of winter sports. As lead environmental, engineering, and design consultant, Barr has provided the civil, geotechnical, structural, mechanical, and electrical design for the impressive landing hill: a 1,111-foot run at grades exceeding 40 degrees.
Athletes will land on a synthetic skiing surface secured to a two-acre concrete slab. On this steep hillside, long-term geotechnical stability is vital and the focus of our design. The slab will be strengthened with reinforcement bars made of basalt—produced locally—to reduce the risk of corrosion compared with steel. Hundreds of rock and soil anchors and high-tensile-strength mesh will secure the slab to the hill. An innovative irrigation system will lubricate the new surface, enabling use without snow.
Our design includes the foundation for the new judge’s tower, which will be elevated 70 feet above ground for sufficient visibility, and a set of nearly 500 continuous steps along both sides of the landing hill for maintenance and access in all seasons.
We are currently overseeing the preparation of the landing hill for its new surface. Blasting and grading are complete, and placement of soil and rock anchors, drainage rock, and mesh has begun. The slab, stairs, and irrigation and drainage system will be completed in 2026.
The renovated Copper Peak facility will be the first of its kind to host international training and competitions for both men and women—introducing new possibilities and expanding global access to the sport of ski jumping.
When a mining client wanted to dewater an active mining area to its tailings basin, Barr developed four potential pipe alignment options and two options for pumping water from the mine to the basin. The plan considered safety, construction phasing, regulatory requirements, and project costs.
The client chose Barr’s design for a year-round, all-weather pumping system that can operate continuously, intermittently, and at a variable flow rate. The dewatering system enables the client to utilize the maximum allowable continuous pumping rate of 5,000 GPM. Throughout the design process, Barr worked closely with a local earthwork contractor, county officials, and Burlington Northern Santa Fe Railroad.
Barr completed a final design of the client’s selected option for a year-round, all-weather pumping system for dewatering the active mining area.
On 61 acres of city-owned land, the South Washington Watershed District seized a rare opportunity to build a new park in Woodbury, Minnesota, that protects lake water quality, nurtures native habitat, and builds public awareness of stormwater management.
The district first hired Barr to evaluate options for preventing excessive nutrients from entering nearby Powers Lake. With a preferred option in hand, the district then hired Barr’s multi-disciplinary team to design a stormwater treatment solution that transformed the undeveloped property into a stormwater-inspired park.
Because the site was undeveloped, there were few limitations to treatment design—allowing the Barr team to fully optimize basin size and pump flows for a highly effective solution. A wetland on the property that was once a source of excessive nutrients to Powers Lake now drains to a series of artful infiltration basins that capture stormwater, filter it, and allow it to seep into the ground.
Soil excavated during basin construction was kept on site to create interesting topography and a park overlook. Barr’s landscape architects adorned the basins with stone spillways and crossings that allow visitors to see and hear water movement. Sculptures and interpretive elements were integrated to inspire appreciation of water quality and the role native plants can play in stormwater management. Unique plantings were selected for each basin that expand the habitat provided by adjacent Hasenbank Woods.
This innovative park provides multiple benefits: water quality improvement, diverse habitats, education, and a unique place for people to experience. Sustainability, biodiversity, soil health, and resiliency were priorities during design, combining the best of a biological solution with an engineered framework.
For a more detailed look at this project, read this article by the project manager and the client's aquatic ecologist.
Since 2012, Barr has been providing engineering, design, and on-site construction support services to Nevada Copper for development of its Pumpkin Hollow underground copper mine and portions of the surface processing facility near Yerington, Nevada, about 75 miles south of Reno. Although design began in 2012, it was paused for several years and was nearing completion in 2022 when the operation went into care and maintenance mode.
Barr started out providing electrical design for a temporary sub-station, temporary hoist house, headframe, and collar house for the east shaft at the Yerington facility. Barr designed a temporary 10 MVA substation for the hoisting and underground operations and redundant underground power distribution at both 13.8 kV and 4.16 kV as well as 480 V. Power distribution supports critical systems such as dewatering, ventilation, and mining operations.
A second phase of the project led to Barr providing a third-party review of the client’s deficient paste plant as well as new engineering work and portions of the detailed electrical design for both underground and aboveground permanent power distribution for the project’s east-shaft area development. Our work entailed mechanical and structural design, updated process flow, power distribution, electrical equipment layouts, PLC control, grounding, lighting, switchgear, communications system, dewatering system, and fiber optic networking.
For the paste backfill portion of the project, we provided engineering services to upgrade and retrofit the newly built paste plant to correct issues that prevented plant operation; the paste plant was designed and supplied by another firm. Upgrades included changes to the binder addition system, adjustment of the conveyors, modification of the tailings hopper, and functional changes to the control system to make the system operable. We performed the engineering and managed the construction of modifications. Barr was in the process of commissioning the plant when operations halted.
Barr also provided engineering services for the overall site plan, headframe, bin house at headframe, hoist and UG substation, hoist house, compressor building, and vent shaft.
For the underground and shaft portion, we provided engineering support for steel, mine dewatering, shaft services, loading pocket, ore and waste bins, rock breakers and grizzlies, crushers and conveyors, shaft station fit out, maintenance shop, refuge station, warehouse and offices, mine ventilation, and mine automation and communications.
Next, Barr provided surface engineering drawings for expanding the hoist house to protect the project’s service hoist, as well as for hoist controls, an electrical room, and mine control facilities. The processing facility of the Pumpkin Hollow underground mine has commenced production using development ore from mine construction, and the underground mine itself began production before the end of 2020.
Barr has provided on-site construction oversight for the mine's electrical infrastructure and aboveground mechanical systems. This has included full-time on-site presence by members of Barr's electrical and mechanical engineering team to provide additional electrical design and start-up and commissioning support, as well as construction observation and management services.