Location: Seattle, WA
Owner: Washington State Department of Transportation
OCI was under contract with HNTB, part of Seattle Tunnel Partners, and developed site specific and construction phase specific TESC Plans and Narrative for the project. Major areas of concern for erosion and sediment transport on this project were the south and north portals, particularly the cut and cover section of the tunnel which involved pile construction, deep excavations, and concrete handling activities associated with viaduct demolition, muck transport, and emergency storage.
OCI completed the engineering analysis needed to obtain the NPDES Construction Stormwater General Permit and the King County Wastewater Discharge Authorization for the project. OCI determined temporary and permanent discharge locations and designed connections to the existing drainage systems. In order to determine discharge capacity of existing outfalls, a backwater analysis for outfall pipes from the regulator discharging to Elliott Bay at the south portal area was conducted. MGSFlood and SBUH design software were used to determine the maximum stormwater flows and volumes expected from the south and north portals based on the maximum footprint of construction activities. This information was then used to determine temporary storage tanks and treatment plant size required to meet discharge standards.
OCI coordinated with the geotechnical engineer for dewatering volumes and assisted in reviewing compliance plans for discharge volumes and water quality. This project involved coordination with the Contractor, design-build permitting team, and various stakeholders on the project such as Seattle Public Utilities, King County, City of Seattle, WSDOT, and Port of Seattle.
OCI worked as an extension of the HNTB drainage design team and assisted with stormwater design and calculations. OCI’s engineers performed QC of the stormwater report and plans.

Service Details >>
- Stormwater Management and Design
- Stormwater Detention, Infiltration, and Treatment Design
- Hydrologic and Hydraulic Modeling
- Stormwater Pollution Prevention Plan (SWPPP) and Narrative
- Temporary Erosion and Sediment Control (TESC) Plans
- Green Streets and On-Site Stormwater Management Approaches
- Bridge Scour Analysis
- Highway Runoff Dilution and Loading Stormwater (HI-RUN) Model
- Culvert Analysis and Design


Laurie is an accomplished hydraulic and transportation engineer with 21 years of experience in designing and managing both public and private projects. Designing and delivering projects across Puget Sound, Laurie’s project experience ranges in size from small intersection improvements to multi-billion dollar mega projects. She excels at managing and organizing the day to day activities of complex projects and design teams, providing coordination, scope compliance, technical guidance, work planning, scheduling, and reporting.
OCI Shareholder and Board Member
Joined OCI: 2013
Education: BS in Civil Engineering, Gonzaga University
Licenses/Certifications: PE in Washington State, Low Impact Development (LID) certification
HOBBIES & INTERESTS
Laurie has an adventurous and inquisitive spirit and enjoys travelling, reading, hiking, camping, biking, and keeping up with her two dogs. She loves exploring and learning interesting facts about the places she and her husband, Jesse, visit on their travels. Laurie plays the fiddle and the concertina in an Irish rock band.