How is the stormwater service fee calculated?
Tumwater’s stormwater service fee is based on the amount of impervious area on each property and is developed using an Equivalent Residential Unit (ERU). Each ERU is equivalent to 3,250 square feet of impervious area and is billed $5.70 per month. The charges to commercial, industrial, and other properties with large impervious areas will be substantially more than single-family residential properties because they create much more runoff.
