Portland International Airport


Portland, OR


Stormwater Engineering

Not only does the Port of Portland has stringent regulatory requirements for managing discharge of stormwater impacted by deicing chemicals from Portland International Airport (PDX), but the Port also faces a unique regulatory situation, as it is limited on what it can discharge to its three primary outlets for stormwater—the Columbia Slough, the Columbia River and the local municipal wastewater treatment facility. These factors led to the need for a highly controlled and monitored deicer management system, and since 2007, Gresham Smith has evaluated, designed and optimized upgrades to the Portland International Airport (PDX) deicing system.

a map illustrating how the deicer management system conveyance maneuvers through the Portland International Airport site

Gresham Smith has been a major contributor to the implementation of the significantly enhanced deicer management system, leading development of the system concept during schematic design, providing high-end computer simulations using our proprietary GlyCAST deicer management software, and leading the design of an anaerobic fluidized bed reactor biological treatment system. Since the deicer management system’s initial construction, Gresham Smith has designed new online total organic carbon (TOC) monitors, which are tied to the control system. The monitors separate clean and contaminated water and further segregate contaminated water into dilute and concentrated fractions to optimize storage and treatment efficiency. Our work at PDX has improved the Port’s ability to achieve compliance with its regulatory permits and provides a significant increase in flexibility for responding to Portland’s highly variable weather and deicing conditions.