Frazer Lake Dam Remediation

  • Location Western Canada

CLIENT: City of Kelowna

PROJECT DESCRIPTION

PRI provided engineering services to the City of Kelowna for the rehabilitation of Frazer Lake Dam, located in the Upper Mission neighbourhood of Kelowna, BC. The preliminary design phase included review of existing documentation, site reconnaissance with a geotechnical subsurface investigation, geotechnical and hydrotechnical analyses, development and evaluation of design alternatives, and a Class C cost estimate. Following preliminary design, the project advanced to detailed design and the completion of tender-ready, issued-for-construction (IFC) drawings and a schedule of quantities.

PRI’s team also completed environmental impact assessments, including several wildlife surveys, and prepared a construction environmental management plan as part of the BC Dam Safety Regulation Plan submission requirements. Key elements of the dam remediation design included:

  • Removal of the existing earthen embankment, concrete headwall, and outlet works
  • Temporary cofferdam design
  • Steel sheet pile cut-off wall
  • Rock ramp spillway channel
  • Cast-in-place concrete level control structure
  • Low-level outlet and gate works

CHALLENGE

Frazer Lake Dam required rehabilitation to meet BC Dam Safety Regulation requirements, but the site’s location within an established residential neighbourhood and its surrounding natural habitat added complexity to the design. The existing earthen embankment, headwall, and outlet works needed to be safely removed and replaced without compromising dam safety during construction, while subsurface conditions had to be well understood to support a durable, code-compliant structure. At the same time, the project needed to account for local wildlife and satisfy the environmental documentation required under provincial dam safety regulations, all while keeping the design on a path to a tender-ready package.

APPROACH

PRI began with a thorough preliminary design phase, reviewing existing records and conducting site reconnaissance, including a geotechnical subsurface investigation, to characterize site conditions. Geotechnical and hydrotechnical analyses informed a set of design alternatives, which were evaluated alongside a Class C cost estimate to guide the City’s decision-making before advancing to detailed design.

The resulting design package paired the removal of the deteriorated earthen embankment, concrete headwall, and outlet works with a temporary cofferdam to allow construction to proceed safely in the dry. A steel sheet pile cut-off wall was incorporated for seepage control, alongside a rock ramp spillway channel, a cast-in-place concrete level control structure, and new low-level outlet and gate works to manage water levels going forward. In parallel, PRI carried out environmental impact assessments and wildlife surveys and developed a construction environmental management plan to satisfy BC Dam Safety Regulation Plan submission requirements, ensuring the design was ready to move directly into tendering.

OUTCOME

PRI delivered a complete engineering solution for the City of Kelowna, from preliminary design through to tender-ready IFC drawings and a schedule of quantities. The rehabilitated dam design meets BC Dam Safety Regulation requirements while incorporating the environmental planning needed to protect the surrounding habitat, giving the City of Kelowna a safe, durable, and regulation-compliant dam for the Upper Mission community.

Vegetation Resource Inventory: Chilcotin Mountains

  • Location Western Canada

CLIENT: Ministry of Forests, British Columbia

Field Data Collection in Support of Annual Allowable Cut Determination

PROJECT DESCRIPTION

PRI conducted a Vegetation Resource Inventory (VRI) field program in the Chilcotin Mountains of British Columbia to collect ground-sample data used in determining the region’s Annual Allowable Cut (AAC). The 11-day field program gathered stand-level forest attribute data across a remote and ecologically diverse landscape, providing the accurate, defensible information provincial timber supply analysts rely on to set sustainable harvest levels.

CHALLENGE

The Chilcotin Mountains present a demanding field environment. Sample sites are remote and rugged, requiring careful trip planning and self-sufficient crews. The area supports an active grizzly bear population, including sows with cubs, which called for heightened wildlife awareness and safety protocols throughout the program. Streams supporting rainbow trout meant that crews needed to work in and around sensitive riparian and aquatic habitat without disturbing it, while persistent mosquito activity added a further layer of field discomfort and required consistent personal protective measures to keep the crew focused and productive over the full 11 days.

APPROACH

PRI’s field crew followed provincial VRI ground-sampling standards to collect consistent, high-quality stand data across the assigned sample grid within the 11-day window. Daily route and site planning incorporated wildlife safety practices, including bear-aware travel in groups, bear spray and noise discipline, and situational awareness around known grizzly activity. Site access and sampling near watercourses were planned to minimize disturbance to rainbow trout habitat and riparian areas. Standard field protective equipment and insect protection were used throughout to keep the crew safe and comfortable in variable bush conditions, allowing the technical sampling work to proceed without interruption.

OUTCOME

The field program was completed safely and on schedule over the 11 days, with no incidents involving wildlife and no impact to sensitive fish-bearing streams. The resulting VRI ground-sample data was delivered to support Annual Allowable Cut determination for the Chilcotin Mountains area, giving decision-makers reliable, field-verified information for sustainable forest management planning in the region.

Conuma Tailings Storage: Wildlife Baseline Assessment

  • Expertise Environmental
  • Market Earth & Environment, Energy & Resources
  • Location Western Canada

CLIENT: Conuma Resources Ltd.

PROJECT DESCRIPTION:

Conuma Resources Ltd. retained PRI in 2021 to develop an environmental baseline for the Willow Creek Extension (WCE) property, located south of Chetwynd, BC, between Conuma’s existing Willow Creek and Brule Mine properties. Conuma has identified WCE as a potential successor to the Willow Creek Mine.

The baseline assessment covered a maximum disturbance area (MDA) of 971 hectares — representing the geographic extent where direct project effects would occur — surrounded by a 2,492-hectare local assessment area (LAA), within which indirect effects could potentially extend into the broader landscape.

CHALLENGE:

To support a future Environmental Assessment Certificate (EAC) Application, Conuma needed a comprehensive, multi-disciplinary environmental baseline that met the data requirements set out by the BC Environmental Assessment Office, specifically:

  • The Joint Application Information Requirements for Mines Act and Environmental Management Act Permits (BC MEMPR / MoECCS, 2019)
  • The Application Information Requirements Guidelines (Province of BC, 2020)

This required coordinating four distinct technical field assessments across a large and ecologically varied landscape, integrating specialized subcontractor expertise while maintaining consistent quality, methodology, and reporting standards suitable for regulatory submission.

APPROACH:

PRI served as both Project Manager and Terrestrial Lead, coordinating a team of specialist subcontracting consultants to deliver four core components of the baseline assessment:

  1. Bioterrain Mapping — supporting Terrestrial Ecosystem Mapping, Terrain Stability Mapping, and Geohazard Mapping (subcontracted to Sitkum Consulting Ltd.)
  2. Terrestrial Ecosystem Mapping (TEM) — including detailed mapping at Ecosystem Survey Intensity Level (ESIL) 4 within the MDA
  3. Rare Plant Assessment (subcontracted to EcoLogic Consultants Ltd.)
  4. Soil and Plant Tissue Sampling for Metals Analysis — with laboratory analysis conducted by ALS Labs, Burnaby, BC (subcontracted to Entia Environmental Consultants)

The mapping work identified Ecosystems at Risk and other valued components, including old forest, wetlands, and riparian ecosystems, ensuring the baseline addressed the full scope of ecological values relevant to a future EAC Application.

OUTCOME:

PRI successfully delivered the Baseline Report to Conuma in March 2022, providing a robust, regulator-ready environmental baseline for the Willow Creek Extension property. The report fulfilled the data requirements outlined in both governing AIR documents, positioning Conuma to advance the WCE property toward a future Environmental Assessment Certificate Application.

LT2 CarbonFree Technology Projects

  • Expertise Geotechnical
  • Market Renewable Energy
  • Location Eastern Canada

CLIENT: Various LT2 Clients

PROJECT DESCRIPTION:
PRI provided on-site support for the CarbonFree Technology LT2 Projects, completing geotechnical investigations and foundation load testing activities for utility-scale solar developments. Drawing on extensive experience across renewable energy projects in Canada, the United States and the Caribbean, PRI applied proven investigation methodologies to deliver the subsurface information needed to reduce foundation-related risk and optimize design.

CHALLENGE:
Utility-scale solar projects carry significant foundation installation risk due to the sheer number of foundations required across variable subsurface conditions — including differing soil types, groundwater, and shallow bedrock. Beyond the solar arrays themselves, major electrical infrastructure such as substations carries substantially greater foundation loads, requiring a deeper and more detailed understanding of ground conditions to avoid costly over-designed foundation which add unnecessary capital expenditures.

APPROACH:
PRI implemented a multi-phase investigation and testing program tailored to the site:

  • Solar array and substation investigations: Standard array foundation investigations were paired with deeper, targeted boreholes at proposed substation and major equipment locations to characterize subsurface conditions under higher foundation loads.
  • Helical pile probing and testing: A series of helical probes were distributed across the site to develop a depth-versus-torque profiles, flag areas of installation difficulty, and inform constructability. Representative helical test piles were then installed and subjected to axial and lateral load testing to validate design assumptions and allowing for further optimization. Axial capacity typically governing the overall length of the foundation in this northern climate due to frost uplift; but considerations of lateral capacity must still be considered and cover the overall shaft size which is primarily impacted by wind loading.
  • Driven pile evaluation: Driven foundations are still the most economical choice for the support of solar racking systems, but may not be feasible due to the increased embedment depth to resist frost uplift. Using the helical probing and geotechnical data, driven pile test locations were selected to compare the performance of W-section and HSS round foundations and ultimately compare to them to the performance of the helical pile option. Installation data (including drive time by depth) were correlated with subsurface findings, and all test piles underwent axial and lateral load testing to confirm capacity and constructability.

OUTCOME:
The combined probing, installation monitoring, and load testing programs allowed PRI to validate foundation performance, confirm constructability across the site, and optimize the final foundation configuration ahead of full-scale production. This proactive, data-driven approach reduced construction risk, improved cost certainty, and gave the project team confidence that the selected foundation systems would meet both structural and constructability requirements — de-risking the project from a geotechnical perspective before installation began at scale.

Kelowna International Airport Culvert Upgrade

  • Expertise Geotechnical
  • Market Transportation & Infrastructure
  • Location Western Canada

CLIENT: Kelowna International Airport (YLW)

PROJECT DESCRIPTION:
The Kelowna International Airport Culvert Upgrade replaced two aging culverts on Mill Creek with a modern, open-bottom box culvert designed to better support natural creek function at the airport site.

CHALLENGE:
The existing culverts were aging and restricted natural creek flow, limiting fish passage and creating flood risk during peak water conditions. Any upgrade needed to address both ecological function and flood resilience without disrupting critical airport operations.

APPROACH:
The team designed and installed an open-bottom box culvert to replace the two existing structures, creating a crossing that better mimics the creek’s natural bed and supports aquatic habitat connectivity, while also improving hydraulic capacity to handle peak flows.

OUTCOME:
The new culvert reconnects approximately 2 km of upstream habitat, improving fish passage and creating healthier conditions for aquatic species. It also enhances flood resilience by reducing bottlenecks during peak flow events, helping protect airport infrastructure, support emergency access, and strengthen long-term operational reliability, demonstrating how targeted infrastructure investments can advance sustainability alongside safety and resilience goals.

925 Laurier Avenue

  • Expertise Structural Egineering
  • Market Property & Buildings
  • Location Western Canada

CLIENT: A Private Developer

PROJECT DESCRIPTION:
925 Laurier Ave — a high-density residential development featuring a concrete podium supporting wood-frame residential units above, designed to maximize footprint and density on a tight urban lot.

CHALLENGE:
The site left little room for error: every square foot had to be maximized to make the project viable, while keeping construction cost-effective. Success depended on solving the “parts no one sees” — the foundations and structural systems — since gaps between consultants on these elements often lead to costly delays and change orders.

APPROACH:
We integrated structural and geotechnical expertise under one roof, treating the building and the ground it sits on as a single problem rather than separate scopes. This eliminated the “seams” between consultants and allowed us to engineer a robust concrete podium to carry the wood-frame units above. We stayed engaged through every phase of construction, from the first foundation pours in winter through final wood-frame assembly, coordinating design from initial concept through completion.

OUTCOME:
The build stayed on schedule, with every detail matching the original coordinated design. The developer received a defensible, buildable project that protects their investment, and future residents gained a reliable, well-engineered home.

Lakeshore Boulevard West Multi-Family Highrise

  • Expertise Geotechnical
  • Market Property & Buildings
  • Location Eastern Canada

CLIENT: Apria Inc.

PROJECT DESCRIPTION:

PRI completed a combined geotechnical and hydrogeological investigation to support the design of a proposed six-storey mixed-use development — 60 residential units over ground-floor retail with two underground parking levels — on a roughly 1,410 m² urban infill site south of Lakeshore Boulevard West. The program characterized the overburden and shale/limestone bedrock, established the groundwater regime and dewatering requirements, and delivered foundation, excavation, shoring and groundwater-control recommendations for redevelopment of the former auto-service property.

CHALLENGE:

The constrained urban infill site abutted existing buildings yet required a two-level basement excavated into shale/limestone bedrock beneath a shallow groundwater table. Interbedded limestone, highly variable rock quality (RQD 0–79%), and groundwater chemistry exceeding City of Toronto sewer-discharge limits added significant excavation, shoring and dewatering complexity.

APPROACH:

PRI delivered an integrated geotechnical, hydrogeological and — with D.M. Wills — environmental program, combining SPT drilling, rock coring and Point Load testing with three months of groundwater monitoring and slug testing. The data were used to model dewatering volumes, define foundation and shoring parameters, and benchmark groundwater quality against municipal discharge criteria.

OUTCOME:

The work confirmed competent bedrock suitable for shallow/raft foundations at 750 kPa (ULS), defined secant-pile shoring and rock-anchor parameters for excavating next to neighbouring buildings, and quantified short- and long-term dewatering rates and permitting requirements (PTTW/EASR). Results were issued in signed Geotechnical and Hydrogeological Investigation reports supporting the City of Toronto SPA/rezoning submission.

Bobcaygeon Beach Park Redevelopment

  • Expertise Geotechnical, Environmental
  • Market Property & Buildings
  • Location Eastern Canada

CLIENT: City of Kawartha Lakes

PROJECT DESCRIPTION:

PRI Engineering was retained by the City of Kawartha Lakes to peer review the geotechnical, environmental and civil design work for the redevelopment of Bobcaygeon Beach Park — a roughly 7.25-acre waterfront municipal park on a former rail maintenance yard adjacent to Big Bob Channel. PRI delivered earthworks and paving recommendations, a supplementary topsoil sampling and TCLP waste-classification program, risk-based management of contaminated soils, dewatering and construction groundwater guidance, and support for the Parks Canada permit and Indigenous consultation.

CHALLENGE:

The public waterfront park sat on a contaminated former rail maintenance yard directly adjacent to the Bobcaygeon River, requiring cost-effective on-site management of impacted soils without risk to human health or aquatic and terrestrial receptors. PRI also had to reconcile multiple prior consultants’ reports and navigate shoreline works that triggered Parks Canada permitting, Indigenous consultation and archaeological review.

APPROACH:

PRI peer-reviewed the existing geotechnical, environmental and civil design packages and supplemented them with an 18-test-pit topsoil sampling and TCLP waste-classification program. A risk-based soil-management strategy (hard and soft caps) was adopted from the Screening-Level Risk Assessment, fill reuse was benchmarked against OPSS 1010 Select Subgrade Material, and dewatering, construction groundwater monitoring and excess-soil screening were addressed alongside Parks Canada permit support.

OUTCOME:

PRI confirmed the contaminants of concern could be safely managed on-site beneath hard and soft caps, and classified the excess topsoil as solid non-hazardous waste suitable for the City landfill — avoiding costly hazardous disposal. Final earthworks, paving, dewatering and excess-soil recommendations were issued, and the City was supported through groundwater sampling, a cost-savings review, and the Parks Canada RSCP permit and Indigenous consultation process.

Georgetown Solar Project

  • Expertise Geotechnical
  • Market Renewable Energy
  • Location Western Canada

CLIENT: Zero E Global Assets

PROJECT DESCRIPTION:

PRI Engineering provided comprehensive geotechnical investigation and foundation design services for a 230 MW solar farm in Mossleigh, Alberta — one of the largest-scale renewable energy projects in the province. The scope covered full subsurface characterization, detailed geotechnical assessment, and foundation design recommendations for both driven and helical pile foundations to support the project through design and construction.

CHALLENGE:

A project of this scale demanded a thorough and reliable understanding of subsurface conditions across a large site to underpin confident foundation design decisions. With both driven and helical pile systems under consideration, geotechnical findings needed to support a cost-effective foundation selection while addressing a broad range of site preparation and construction considerations — from groundwater control and frost protection to seismic classification and access road design.

APPROACH:

PRI advanced 30 boreholes and excavated one test pit to characterize subsurface conditions across the site. The geotechnical assessment delivered detailed recommendations spanning site preparation, excavation, groundwater control, backfill and compaction, frost protection, seismic site classification, access road design, and inspection and testing requirements. PRI recommended a pre-production testing program to verify soil capacity and support an issued-for-construction foundation design, including settlement analysis and foundation design parameters. Findings from the investigation informed tailored recommendations for both driven and helical foundation systems.

OUTCOME:

PRI delivered a comprehensive geotechnical investigation and foundation design package that gave the project team the technical confidence to move forward at scale. The dual-system foundation recommendations — balancing performance, site conditions, and cost-effectiveness — provided a strong and practical basis for construction of one of Alberta’s most significant solar energy developments.

Mckinley Beach Pool & Amenity Building

  • Expertise Structural Egineering
  • Market Property & Buildings
  • Location Western Canada

CLIENT: Mckinley Beach Corporation

PROJECT DESCRIPTION:

North American Group retained PRI for the structural design of the new Mckinley Beach Pool and Amenity Building in Kelowna. The facility features an indoor leisure pool with changing rooms, a large glazed gymnasium, second-level administration offices and boardrooms, and an external hot tub at the south entrance of the pool area.

CHALLENGE:

The project presented multiple structural complexities, including snow drift loads, heavy mechanical equipment on the roof, and a sloping site. The client’s desire for extensive glazing on the south face of the building significantly reduced available shear wall length, requiring an innovative approach to lateral load resistance. Additionally, the long internal spans required for the pool and gymnasium spaces, combined with mixed steel, timber, and concrete construction, demanded careful coordination across all structural systems.

APPROACH:

PRI designed a structural system combining glue-laminated beams and columns with conventional timber construction and shear walls to achieve the required spans and lateral stability. To accommodate the client’s vision for unobstructed south-facing glazing, the upper and lower roofs were designed as cantilevered diaphragm ceilings, eliminating the need for columns or shear walls along the glazed elevation. Roof structures were engineered to carry heavy mechanical equipment loads alongside snow drift demands, and all systems were carefully coordinated across the sloping site and mixed construction materials.

OUTCOME:

PRI delivered a fully integrated structural design that balanced the facility’s complex technical demands with the client’s architectural vision. The McKinley Beach Pool and Amenity Building was on track for completion in July 2024, providing the Kelowna community with a modern recreational facility featuring open, light-filled spaces and unobstructed views to the south.