Kitsap County, WA Landscaping Rules: Rainwater Harvesting (2026)
Key Facts
- Credit amount
- 50% rate reduction on harvested surfaces
- Governing section
- KCC § 12.40.040(5)(A)
- Certification required
- Licensed professional engineer analysis
- Technical standard
- Zero surface discharge in all storm events
- To keep credit
- Annual Public Works inspection
- Coverage area
- Unincorporated Kitsap County only
- Effective date
- Following calendar year after request
Summary
Kitsap County lets owners of developed, unincorporated-area parcels retrofitted for rainwater harvesting apply for a 50% stormwater utility rate reduction on the surfaces where rain is captured, under Kitsap County Code § 12.40.040(5)(A). A licensed professional engineer must certify zero surface discharge in all storm events, and Public Works inspects the system annually to keep the credit active.
(5) Class 5: All other property shall have the service charge of measured impervious surface area divided by the square footage of one ESU (four thousand two hundred), rounded to the nearest ESU but not less than one, multiplied by the unit rate. These service charges may be reduced as follows: (A) Rainwater Harvesting Rate Reduction. Any developed parcel that is retrofitted for rainwater harvesting may receive a fifty percent rate reduction for those surfaces from which the rain is harvested. To be eligible for this fifty percent rate reduction, the proponent must demonstrate through an analysis prepared by a licensed professional engineer that the system will result in zero surface water discharge for all storm events using the hydrologic methods described in the current Kitsap County or Washington Department of Ecology Stormwater Design Manual. The proponent is responsible for requesting the credit. The rate reduction will become effective for the calendar year following the request. Annual inspections by the department of public works to ensure proper operation and maintenance will be required to retain this rate reduction.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: rev 4864424; v0 updated 2025-12-08; through 12-08-2025).
Full Breakdown
040). Most developed parcels fall into Class 5, billed for measured impervious area divided by 4,200 square feet, rounded to the nearest ESU. 040(5): the Rainwater Harvesting Rate Reduction, the Full Infiltration Rate Reduction, and the Direct Discharge to Tidally Influenced Waters Rate Reduction. 040(5)(A), a property owner who retrofits a developed parcel to harvest rainwater can cut the stormwater rate by 50% on the specific surfaces from which rain is captured. Qualifying requires a licensed professional engineer's analysis showing the system produces zero surface water discharge for all storm events, using the hydrologic methods in the current Kitsap County or Washington Department of Ecology Stormwater Design Manual.
The property owner, not the county, must affirmatively request the credit from the department of public works; approval takes effect the following calendar year, not retroactively. To keep the reduction, the department of public works conducts annual inspections confirming the harvesting system still operates and is maintained. The same 50% reduction and inspection requirement also applies to the Full Infiltration credit under subsection (B) and, separately, to the Direct Discharge to Puget Sound credit under subsection (C). 060, due by April 30, or split with the balance due October 31.
Because this is a Washington county ordinance, it governs only unincorporated Kitsap County; Bremerton, Port Orchard, Poulsbo and Bainbridge Island run their own separate stormwater utilities and are not bound by KCC Title 12.
Violations & Fines
Kitsap County Code doesn't set a separate fine for losing this credit: failing the annual department of public works inspection, or letting the harvesting system fall out of operation, simply reverses the reduction and returns the parcel to its full Class 5 stormwater rate the following billing cycle. Unpaid or restored stormwater charges become delinquent if not paid by April 30, or October 31 for the deferred half, under § 12.40.060, and follow the same collection and lien procedures as other Title 12 utility charges.
Frequently Asked Questions
Does Kitsap County require rainwater harvesting systems?
How do I get the 50% rainwater harvesting credit?
Does the rainwater harvesting credit apply inside Bremerton or Poulsbo?
What happens if I stop maintaining my harvesting system?
Sources & Official References
Other rules in Kitsap County
Compare Kitsap County to another location·View the Washington landscaping rules overview
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