Project Library

King County Metro Interim Base Electrification – Construction Stormwater

Tukwila, Washington

King County Metro Interim Base Electrification – Construction Stormwater

King County Metro Transit is leading the charge towards a zero-emission future with its ambitious $115 million Interim Base Electrification (IBE) project, designed to support 120 zero-emission buses at the Interim South Base. As the first project of its kind in the region, it serves as a benchmark for similar initiatives.

In collaboration with General Contractor McKinstry, WaterTectonics is responsible for managing stormwater and groundwater treatment to comply with Construction Stormwater General Permit (CSWGP) limits. Our comprehensive approach included: developing Stormwater Pollution Prevention Plans (SWPPP) and preparing comprehensive submittal packages for King County Metro; successfully navigating NPDES permitting which was especially challenging due to the impaired status of the Lower Duwamish receiving waters for pH; conducting Certified Erosion and Sediment Control Lead (CESCL) monitoring for effective stormwater management; providing full-service expert consulting services to ensure compliance with environmental regulation; and deploying a fully automated, 300 gallon per minute electrocoagulation (EC) system.

Our work ensures that all stormwater and groundwater discharge meets stringent environmental standards, supporting King County Metro’s goal of a sustainable, zero-emission transportation network. This project not only showcases innovative water treatment solutions but also sets a precedent for future sustainable infrastructure projects in the region.

Icon of a construction crane.

Treatment Systems

Contaminants Targeted

What We Treat