About Washington Stormwater LLC
Washington Stormwater provides innovative Chitosan Enhanced Sand Filtration (CESF) units for construction sites across Washington, to lower your project costs and improve site safety. Our innovative, self-contained units use biodegradable Chitosan (derived from crab shells) to filter contaminants from construction site runoff so it’s safe to re-enter the environment.


Where We Started
Our founder Jim Thorwart worked in the erosion control business for over 20 years. In that time he saw ecology standards tightening and not many suppliers offering environmentally friendly, cost-effective, and easy-to-install filtration solutions for the turbid water on construction sites.
He took it upon himself in 2005 to reach out to Hach Components and other manufacturers, to acquire the parts to design and distribute his own turbid water filtration system that use chitosan in the filter system.

Who We Are
Bobbi is our team President and brings with her over 11 years of accounts payable and receivable experience. She’s worked in many industries including architecture firms and medical distribution, and is highly skilled in payroll, invoicing, and account balancing.
Tyson is Washington Stormwater’s Vice President and has worked in the heavy civil engineering field for over 18 years as a project manager (estimating, cost tracking, budgeting, scheduling, and safety). He worked mostly in the public sector managing projects for local municipalities, Sound Transit, and WSDOT.
His experience gives him a well-rounded view of the whole construction industry, including a high-level understanding of the complex change order process, local county and federal laws, permits, property acquisition, billing, and tax rules.
Tyson and Bobbi are the parents of two boys and as a family they love the outdoors and can often be found hiking, biking, or swimming together.
