Cleaning Rainwater Beautifully

Project: Whispering Firs Stormwater Park

Designers: NL Olson & Associates and Parametrix

Location: Silverdale, WA

Iron Age’s decorative grates are used in the design of this innovative park, which not only provides a beautiful setting for the community to enjoy, but also filters stormwater from 115 acres of upstream development. Previously this stormwater flowed into a nearby creek with little or no treatment.

An entire community’s rainwater in one park

Diverted stormwater flows through our grates and into a series of channels and treatment cells. Massive planters filled with native plants and special soils remove pollutants from the runoff before sending it to holding ponds. Clean water is slowly released, eventually joining the Puget Sound.

Project Benefits:

  • Treats 115 acres of stormwater runoff, approximately 100 million gallons per year
  • Reduces localized flooding during storm events
  • Over the next 10-20 years, the system will prevent 100,000 pounds of pollutants from reaching Puget Sound
  • Achieves current treatment standards of 91% of storm flows
  • Delivers cleaner runoff to Clear Creak and Puget Sound
  • Benefits the community by providing a beautiful park and walking trail system for the community to enjoy year round


“The functional purpose of the circles is to start and stop people on their walk through the park, waypoints to aid a sense of arrival. Their concentric repetition resembles water drops in a still pool” — Jens Swenson, Landscape Architect, Parametrix

We are grateful for the opportunity to partner with project designers NL Olson & Associates and Parametrix, and proud of the role we all play in helping to create a cleaner environment and more sustainable future.