Off-grid site report
Whatcom County, WA
48.7912, -122.4954 · 164 ft elevationRead this before you act on anything below. This is my researched starting point for Whatcom County, WA, not legal advice and not a guarantee. Rules change, and the deciding facts on any specific parcel (setbacks, perc results, overlay districts, deed restrictions, road frontage) live at the county or town office, not in any database. Before you buy land or build, confirm the current rules directly with the local zoning and health offices - the sources on this page tell you exactly who to call.
The local rulesWhatcom County, WA
Zoning & raw-land occupancy
Varies locallyWhatcom County has countywide zoning under Title 20, administered by Planning & Development Services; rural land is split into districts (Rural, Residential Rural, Rural Forestry, Agriculture) with different permitted uses, so status depends on the specific parcel's zone. source
Dwellings, tiny homes & RVs
Varies locallyThe county has been amending Title 20 to allow tiny homes on individual lots or in parks, per state legislative changes; site-built tiny homes are reviewed under Appendix Q, but wheeled tiny homes/RVs remain under the standard state RV framework. source
Building permits & codes
Generally allowedWhatcom County PDS administers the state building code locally for permits and inspections; no local loosening of the statewide minimum code was found. source
Septic & composting toilets
RestrictedThe county Health Department's OSS Program permits septic systems under county code Chapter 24.05 aligned with state WAC 246-272; composting toilets are allowed in principle, but the department has in practice favored proprietary state-listed units over site-built designs, which is stricter than the bare state rule. source
Greywater reuse
Unclear - verifyState rule (WAC 246-274) allows tiered greywater reuse, but it only applies where the local health jurisdiction has implemented it; Whatcom County's adoption status was not confirmed, so ask the county Health Department directly. source
Rainwater harvesting
Varies locallyNon-potable rainwater collection is fine under the state baseline; using rainwater as a primary potable source reportedly needs county Health Department approval, but the exact procedure is not confirmed on an official county page. source
Private wells & water rights
Varies locallySince the state's 2016 Hirst decision, exempt-well permitting has tightened statewide, and Whatcom's zoning code ties minimum lot size to public water availability; specific post-Hirst watershed restrictions in the county were not independently confirmed, so check with Washington Department of Ecology and county PDS. source
Living disconnected from utilities
Unclear - verifyNo standalone Whatcom County ordinance bans full utility disconnection, but zoning, building code, septic, and water-supply approvals collectively act as gatekeepers, mirroring the state baseline. source
Sun30-year normals
- Peak-sun hours, annual average
- 3.7 hrs/day
- Worst month (sizes an off-grid array)
- 1.3 hrs/day
- Yearly output per 1 kW of panels
- 1,039 kWh
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Weather1991-2020
- Precipitation
- 35 in/yr
- Snowfall
- 4 in/yr
- Heating degree days
- 4,902 (moderate)
- Frost-free season
- Mar 29 to Nov 6
How far help isstraight-line
- Hospital
Emergency - 35.1 mi
- Fire station
Fire Station #6 - 0.8 mi
- Hardware store
Harbor Freight Tools - 2.0 mi
- Grocery
Safeway - 2.0 mi
From OpenStreetMap. Road miles will be longer, often much longer in hill country.
Plan this spot
These open with this location's real numbers already filled in (ZIP 98227).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Whatcom County, WA?The rules above are the jurisdiction. The land check runs the parcel itself: flood zone, soils and septic suitability, wetlands, slope, access, climate, and these verdicts, from a parcel number or coordinates.
Check a parcel →Share or save this report:New report
Sources: US Census Bureau geocoder; NLR PVWatts v8 (solar); NOAA NCEI 1991-2020 climate normals (nearest station) or Open-Meteo (ZIP-centroid) for weather; Open-Elevation; OpenStreetMap contributors. Public data retrieved Aug 21, 2026; agencies update their layers on their own schedules. Planning data, not a survey or legal advice.