Whatcom County, WA Landscaping Rules: Rainwater Harvesting (2026)
Key Facts
- Credit amount
- 10% of annual stormwater fee
- Eligible buildings
- new or remodeled commercial only
- State authority
- RCW 36.89.080
- Service area
- Lake Whatcom Stormwater Utility
- Request deadline
- 30 days of bill date
- Appeal deadline
- 30 days of manager decision
Summary
Inside the Lake Whatcom Stormwater Utility Service Area, a new or remodeled commercial building gets a 10% credit off its annual stormwater fee for installing a permissive rainwater harvesting system sized to the building's available roof surface, per WCC § 16.30.080(B)(5).
5. The parcel contains a new or remodeled commercial building that utilizes a permissive rainwater harvesting system that is properly sized to utilize the available roof surface of the building; or a. For qualifying permissive rainwater harvesting systems as provided for under RCW 36.89.080 and eligible under subsection (B)(4) of this section the formula is expressed mathematically as follows: A = F x 10% Where: A = The credit amount to be subtracted from the annual fee; and F = The total fee without credit.
Full Breakdown
060). 080. The credit is calculated as A = F x 10%, where F is the total annual fee without the credit and A is the amount subtracted from it. 420) and a contiguous-parcel adjustment for same-owner single-family lots. 080(A)); filing does not extend the payment deadline. The manager decides within 60 days based on submitted evidence, and the burden of proof rests on the owner. 080(C)-(D)).
Violations & Fines
There is no separate penalty for skipping the credit: a property simply pays the full unit-rate stormwater charge without the 10% reduction. A manager's denial of a rainwater-harvesting credit request becomes final unless the owner files a written appeal to the Whatcom County hearing examiner within 30 days of the decision (WCC § 16.30.080(E)). Unpaid stormwater charges (with or without credit) become delinquent after April 30 or October 31 and accrue 8% annual interest plus up to a 10% penalty under RCW 36.94.150 (WCC § 16.30.070, § 16.30.110).
Frequently Asked Questions
Does installing a rainwater harvesting system lower my Whatcom County stormwater bill?
Can a single-family homeowner get the rainwater harvesting credit?
How do I apply for the credit and what if it's denied?
Sources & Official References
Other rules in Whatcom County
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