The purpose of the Transitional Zone District is to maintain the low density residential character of the areas designated as transitional on the official Whatcom County zoning map and to implement the goals and policies of the subarea Comprehensive Plan. In addition, it is the intent of this district to create and protect a permanent network of interconnected open space and to provide the opportunity for development of building sites which maximize the efficient use of both infrastructure and land by allowing an option for clustering residential lots.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2012-032 § 2 Exh. B, 2012)
Unless otherwise provided herein, permitted, accessory and conditional uses shall be administered pursuant to the applicable provisions of Chapters 20.80 WCC (Supplementary Requirements) and 22.05 WCC (Project Permit Procedures), the Whatcom County SEPA Ordinance, the Whatcom County Subdivision Ordinance and the Whatcom County Shoreline Management Program.
.051 
One single-family dwelling per lot.
.052 
Public parks and recreation facilities included in an adopted city or county Comprehensive Plan or Park Plan.
.053 
Agriculture including animal husbandry, horticulture, viticulture, floriculture, silviculture, and beekeeping; and the cultivation of crops.
.054 
One one-story detached accessory storage building per lot; provided, that the floor area shall not exceed 200 square feet and shall only be used for personal storage and not for habitation or business; and provided further, that the storage building shall contain no indoor plumbing but may be served with electrical power for lighting.
.056 
Repealed by Ord. 2022-012.
.057 
Forest preserves, wildlife reserves, natural systems education, and/or interpretive areas.
.058 
Trails, trailheads, restroom facilities and associated parking areas for no more than 30 vehicles.
.059 
Co-living housing, provided the density requirements in WCC § 20.20.252 are not exceeded.
.088 
Adult family homes as defined in Chapter 70.128 RCW.
.089 
Boarding homes that are similar in size, facilities and occupancy to other residential structures permitted in the zoning district.
.090 
Mental health facilities that provide residential treatment and are similar in size, facilities and occupancy to other residential structures permitted in the zoning district.
.091 
Substance abuse facilities that provide residential treatment and are similar in size, facilities and occupancy to other residential structures permitted in the zoning district.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2004-014 § 2, 2004; Ord. 2004-026 § 1, 2004; Ord. 2005-079 § 1, 2005; Ord. 2022-012 § 1 (Exh. A), 2022; Ord. 2025-060, 12/9/2025)
.101 
Home-based businesses, pursuant to WCC § 20.80.970.
.102 
Private noncommercial boat docks, launches, ramps, floats, moorages and boathouses pursuant to the Whatcom County Shoreline Management Program.
.103 
Other accessory uses incidental to the primary permitted use.
.104 
Temporary dwelling units which have full living accommodations including sleeping, self-contained cooking, bathing, and toilet facilities where the plumbing is connected to permanent site sewerage and water systems, including those travel trailers and recreational vehicles that meet the above description, for use by owners during the period of construction of a permanent dwelling while building permit is valid, not to exceed two years.
.105 
Hiking, jogging, cross-county ski trails, and bicycling trails.
.106 
Repealed by Ord. 2022-012.
.107 
Bed and breakfast establishments.
.108 
Vacation rental units.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2009-033 § 1 (Att. A), 2009; Ord. 2009-034 § 1 (Att. A), 2009; Ord. 2010-030 § 1 (Exh. A), 2010; Ord. 2016-011 § 1 (Exh. D), 2016; Ord. 2022-012 § 1 (Exh. A), 2022; Ord. 2023-041 § 1 (Exh. A), 2023; Ord. 2025-020 § 1 (Exh. A), 2025)
The following uses are permitted subject to administrative approval pursuant to WCC § 22.05.028:
.131 
A temporary second dwelling unit of no more than 1,248 square feet in floor area, in the form of a manufactured home, a fully serviced travel trailer, park model trailer, or motor home, to provide:
(1) 
A temporary dwelling space for family members who, due to professionally documented physical or mental disorders, or risks of such disorders, require supervision and care where such care is provided by members of the family who reside on the property; or
(2) 
A temporary dwelling space for a person providing care for the resident owner of the subject property when said owner needs supervision and care as described in (1) above.
Approval Requirements:
Administrative approval for temporary second dwelling units shall be approved if it is determined that the proposal meets the following requirements:
(1) 
Temporary second dwelling units shall only be permitted on fully serviced parcels on which the applicant can meet setback, ingress, egress, height restrictions, and lot coverage requirements.
(2) 
The size of the temporary dwelling shall be appropriate to the use and size of the parcel and shall be limited so as to comply with the standards set forth in (1) above.
(3) 
The temporary home shall be connected to an approved water supply and adequate capacity sewage disposal system approved by the Whatcom County health department.
(4) 
When care is no longer necessary, the temporary home shall be removed within 60 days.
(5) 
The permit shall be valid for one year. The permit may be extended on a yearly basis; provided, that an affidavit is furnished by the permittee affirming that the circumstances allowing the original permit remain in effect.
(6) 
A covenant shall be filed that restricts sale of the property while the temporary dwelling is in place.
(7) 
The use will not be hazardous or disturbing to existing or future neighboring uses.
(8) 
Evidence of adequate off-street parking space shall be provided.
(9) 
There shall be no occupancy of the temporary dwelling outside the conditions under which the temporary dwelling is permitted pursuant to this section.
(10) 
All mobile homes must demonstrate compliance with minimum HUD Fire Safety Standards and compliance with current Washington Administrative Code (WAC).
Penalties: False statements on supporting documentation submitted with the application or failure to comply with any of the approval requirements may be cause for revocation of the permit and prosecution.
.132 
Accessory dwelling units, when consistent with WCC § 20.80.910.
.133 
Mini-day care homes.
.134 
Type II home-based businesses pursuant to WCC § 20.80.970.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2005-079 § 1, 2005; Ord. 2006-061 § 1 (Att. A)(7), 2006; Ord. 2009-034 § 1 (Att. A), 2009; Ord. 2010-016 § 1 (Exh. A), 2010; Ord. 2019-013 § 1 (Exh. A), 2019; Ord. 2021-059 § 3 (Exh. C); Ord. 2023-018 § 1 (Exh. A), 2023; Ord. 2025-020 § 1 (Exh. A), 2025)
Items indicated by an "[1]" are not allowed unless the applicant can demonstrate that the proposed use is needed to comply with legal requirements or standards; or that the proposed location is the most efficient place for the proposed use with respect to providing needed services to the public.
.151 
Public and community facilities including police and fire stations, libraries, community centers, recreation facilities, activity centers, and other similar noncommercial uses.[2]
[2]
Code reviser's note: The amendments of Ordinance 2005-039 concerning mushroom composting, extending amendments from Ords. 2004-053, 2004-027, 2003-050, 2003-027, 2002-068, 2002-061 and 2002-033, expired October 24, 2005. Refer to Chapter 20.15 WCC for current provisions concerning mushroom substrate production facilities.
.152 
Public schools; and parochial or private schools; provided such schools shall be approved by the State Superintendent of Public Instruction.[3]
[3]
Code reviser's note: The amendments of Ordinance 2005-039 concerning mushroom composting, extending amendments from Ords. 2004-053, 2004-027, 2003-050, 2003-027, 2002-068, 2002-061 and 2002-033, expired October 24, 2005. Refer to Chapter 20.15 WCC for current provisions concerning mushroom substrate production facilities.
.153 
Churches, educational and religious training institutions, summer camps and cemeteries.
.154 
Retirement and convalescent homes; social and health rehabilitation centers; day care centers; mini-day care centers; and adult care centers not in a family dwelling; and other health-related services consistent with the purpose of the district.[4]
[4]
Code reviser's note: The amendments of Ordinance 2005-039 concerning mushroom composting, extending amendments from Ords. 2004-053, 2004-027, 2003-050, 2003-027, 2002-068, 2002-061 and 2002-033, expired October 24, 2005. Refer to Chapter 20.15 WCC for current provisions concerning mushroom substrate production facilities.
.155 
Golf course.
.156 
Bed and breakfast inns.
.157 
Type III home-based businesses, pursuant to WCC § 20.80.970.
.158 
Private, noncommercial boat docks, launches, ramps, floats, moorages and boathouses pursuant to the Whatcom County Shoreline Management Program for owners of legal lots of record abutting the shoreline. The conditional use permit shall be approved if the hearing examiner finds that the proposal will not be hazardous or disturbing to neighbors and all applicable zoning requirements are satisfied. The criteria of WCC § 22.05.026 shall not apply.
.159 
Plant nurseries and greenhouses for storage, propagation and culture of plants, including sales as an accessory use provided:
(1) 
Must be located on a collector, arterial or higher classified road.
(2) 
Covered sales area and associated display areas must not exceed 10 percent of the total area of the proposed nursery and/or greenhouse(s).
(3) 
There shall be fixed hours of operation.
(4) 
Parking lot, indoor sales or other potential impacts related to operations shall be buffered from neighbors.
(5) 
Signage shall be aesthetically compatible with the character of the neighborhood.
(6) 
All other criteria for conditional use permits must be met.
(7) 
Outdoor storage of fertilizer is prohibited.
(8) 
No aerial application of chemical products shall be allowed within 50 feet of dissimilar uses.
.160 
Public or private parks that are not included in an adopted city or county Comprehensive Plan or Park Plan.
.161 
Public campgrounds.
.162 
Trailheads with parking areas for more than 30 vehicles.
.163 
Athletic fields.
.183 
State education facilities.
.184 
Minor state and local correction facilities with 10 or less beds.
.185 
Type I solid waste handling facilities.
.186 
Type II solid waste handling facilities.
.189 
Boarding homes that are larger than other residential structures permitted in the zoning district.
.190 
Mental health facilities that provide residential treatment and are larger than other residential structures permitted in the zoning district.
.191 
Substance abuse facilities that provide residential treatment and are larger than other residential structures permitted in the zoning district.
.192 
Mental health facilities that provide crisis care.
.193 
Substance abuse facilities that provide crisis care.
.194 
Outpatient mental health facilities.
.195 
Outpatient substance abuse treatment facilities, including opiate substitution treatment clinics.
.196 
Mitigation banks as a form of compensatory mitigation for wetland and habitat conservation area impacts when permitted in accordance with the provisions of Chapter 16.16 WCC; provided, applications for mitigation banks shall be processed as a major development project pursuant to Chapter 20.88 WCC.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2004-014 § 2, 2004; Ord. 2004-026 § 1, 2004; Ord. 2005-068 § 2, 2005; Ord. 2009-033 § 1 (Att. A), 2009; Ord. 2009-034 § 1 (Att. A), 2009; Ord. 2025-020 § 1 (Exh. A), 2025)
[1]
Code reviser's note: The amendments of Ordinance 2005-039 concerning mushroom composting, extending amendments from Ords. 2004-053, 2004-027, 2003-050, 2003-027, 2002-068, 2002-061 and 2002-033, expired October 24, 2005. Refer to Chapter 20.15 WCC for current provisions concerning mushroom substrate production facilities.
All uses not listed as permitted, accessory, administrative approval, or conditional uses are prohibited, including but not limited to the following, which are listed here for purposes of clarity:
.201 
Reserved.
.202 
Adult businesses.
.210 
Secure community transition facilities for sex offenders.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2004-014 § 2, 2004; Ord. 2016-011 § 1 (Exh. L), 2016)
For the purpose of creating new building lots within the Transitional Zone District, two options are provided for calculating land use densities. The minimum building lot size and maximum density requirements for new construction vary according to the method of subdivision and whether or not public water and/or sewer are available to serve the site.
(1) 
Where the conventional subdivision method is used to create new building lots, the minimum lot size shall be five acres.
(2) 
The cluster subdivision method shall only be used to create new building lots if a permanent "open space reserve area" meeting the requirements of WCC § 20.37.321 and § 20.37.322 is created as part of the subdivision. The minimum building lot size for a cluster subdivision with public water shall be 12,500 square feet and the minimum building lot size for a cluster subdivision with public water and public sewer shall be 5,000 square feet.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2005-048 Exh. A, 2005)
District
Gross Density
Minimum Lot Size
Min. Reserve Area (Cluster Subdivisions)
Conventional
Cluster
A conventional subdivision without public water or sewer
1 dwelling unit/ 5 acres
5 acres
N/A
N/A
A cluster subdivision with public water and a permanent open space reserve area
1 dwelling unit/ 1 acre
N/A
12,500 sq. ft.
50%
A cluster subdivision with public water, public sewer, and a permanent open space reserve area
1 dwelling unit/ 1 acre
N/A
5,000 sq. ft.
50%
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2005-048 Exh. A, 2005)
District
Width at Street Line
Width at Bldg. Line
Minimum Mean Depth
Conventional
Cluster
A conventional subdivision without public water or sewer
300'
N/A
80'
100'
A cluster subdivision with public water, an open space reserve area, and/or public sewer
N/A
30'
60'
100'
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2005-048 Exh. A, 2005)
The purpose of lot clustering is to provide an alternative method of creating building lots with spatially efficient sizes. Clustering is intended to consolidate development and associated infrastructure, reduce development costs, and increase infrastructure efficiency. The clustering option is also intended to help preserve open space and the character of areas, reduce total impervious surface area, and minimize development effects on critical areas and associated buffers, as defined in Chapter 16.16 WCC, and resource lands. Preservation of open space is thereby intended to reduce potential stormwater runoff and associated impacts while assuring protection of viable, undeveloped, and naturally vegetated corridors for wildlife habitat, preservation of critical areas, protection of watersheds, preservation of aesthetic values including view corridors, and preservation of trail and/or recreation areas.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2005-048 Exh. A, 2005)
The creation of new building lots, pursuant to this section, shall be subject to the following design standards:
(1) 
Clustered building lots may only be created through the subdivision process, short subdivision process, or binding site plan process pursuant to WCC Title 21.
(2) 
A cluster subdivision shall include a permanent open space reserve area consisting of at least 50 percent of the parent parcel. The open space reserve area shall meet the criteria established in WCC § 20.37.322.
(3) 
Building lots shall be designed and located to be compatible with, and avoid disturbance of, critical areas, other valuable or unique natural resource features or known archaeological sites, as well as physical constraints of the site.
(4) 
Building lots shall be arranged in a cluster/concentrated pattern.
(5) 
A cluster subdivision shall have no more than two common encroachments on existing county roads unless site constraints require additional road access. The arrangement of clustered building lots shall be designed to avoid development forms commonly known as linear, straight-line or highway strip patterns.
(6) 
As applicable, interior streets shall be designed to allow future vehicular access to any portion of the reserve tract which may be divided into future building lots; provided, that the minimum required permanent open space reserve area, pursuant to WCC § 20.37.320, shall not be further divided.
(7) 
In order to preserve rural character, the maximum number of lots in a lot cluster shall be 10. Any number of lot clusters may be used.
(8) 
Clusters containing two or more lots of less than one acre within a proposed development shall be separated by at least 80 feet.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2005-048 Exh. A, 2005)
.321 
For the purposes of this title, an "open space reserve area" shall be defined as that portion of a subdivision or short subdivision set aside in accordance with this chapter, and permanently dedicated for active or passive recreation, critical area protection, natural resource or archaeological site preservation, wildlife habitat and/or visual enjoyment, and shall be consistent with the definition of "open space" found in Chapter 20.97 WCC.
.322 
The minimum open space reserve area required by WCC § 20.37.253 shall be subject to the following provisions:
(1) 
A permanent protective mechanism shall be legally established to ensure that the required open space reserve area is preserved and protected in a manner sufficient to protect the open space reserve area in perpetuity in a form that is acceptable to both the applicant and the county and filed with the county auditor's office. A permanent open space reserve area shall be protected using one of the following mechanisms:
(a) 
Placement in a separate non-building tract owned in common by all lots within the subdivision;
(b) 
Covered by a protective easement or public or private land trust dedication which protects at least the minimum required 50 percent open space reserve area;
(c) 
Preserved through an appropriate permanent protective mechanism that provides the same level of permanent protection as subsection (1)(a) of this section as determined by the county zoning administrator or hearing examiner which applies to at least the minimum required 50 percent open space reserve area.
(2) 
The 50 percent open space reserve area shall contain the following:
(a) 
A minimum 20-foot buffer along the perimeter of the parent parcel, exclusive of dedicated vehicular and non-vehicular site access; and
(b) 
Unique or known archaeologically significant sites, high value natural resource areas, and/or critical areas and associated buffers as defined in Chapter 16.16 WCC.
(3) 
The boundaries of the open space portion of the reserve area may be altered only if the county finds that in dedicating adjacent reserve areas it would further the objectives listed in WCC § 20.37.305 by altering the reserve area and increasing the area of reserve proportionately on the adjacent land being subdivided so that there is no net reduction in open space reserve area.
(4) 
The definition of open space reserve area, as stated in WCC § 20.37.321, shall be recorded as a restriction on the face of the final plat or short plat.
(5) 
The remaining unused development density on the parcel containing the open space reserve area, based on the gross density of the parent parcel, may be assigned to that portion of the reserve area not subject to the minimum reserve area requirements of subsection (1) of this section. The remaining density shall be recorded on the face of the final plat or short plat.
(6) 
The mechanism(s) implemented under subsection (1) of this section, as well as the above stated requirements of subsections (2) and (3) of this section shall be recorded as a restriction on the face of the final plat or short plat, and shall constitute an agreement between Whatcom County and the current/future owner(s) of record that shall run with the land. Restrictions under subsections (2) and (3) of this section may be amended by mutual agreement between said parties after review for consistency and compliance with the official Whatcom County Zoning Ordinance, the Whatcom County Subdivision Ordinance and the Whatcom County Comprehensive Plan.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2005-048 Exh. A, 2005; Ord. 2023-042 § 1 (Exh. A), 2023)
Maximum height shall be limited to 25 feet. Height of structures shall also conform, where applicable, to the requirements of WCC § 20.80.675, § 20.72.400, and the provisions of the Shoreline Management Program, whichever is more restrictive.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003)
Except as follows, no structure or combination of structures shall occupy or cover more than 5,000 square feet or 20 percent, whichever is greater, of the total lot area, not to exceed 25,000 square feet. Public community facilities that serve a predominantly rural area shall occupy or cover no more than 35 percent of a lot, with no limitation on structure (or combination of structures) size. Buildings used for livestock or agricultural products shall be exempt from this lot coverage requirement.
(Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2012-032 § 2 Exh. B, 2012; Ord. 2019-033 Exh. A, 2019)
All discretionary project permits for land on or within one-half mile of an area designated as rural or within 500 feet of an area upon which farm operations are being conducted shall be subject to the right to farm disclosure policies contained in WCC Title 14, Use of Natural Resources.
(Formerly 20.37.652; Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2022-012 § 1 (Exh. A), 2022)
All development activities are subject to the stormwater management provisions of WCC § 20.80.630 through § 20.80.635. No project permit shall be issued prior to meeting those requirements.
(Formerly 20.37.656; Ord. 2002-018 § 1, 2002; Ord. 2003-048 Exh. A, 2003; Ord. 2013-057 § 1 (Exh. A), 2013; Ord. 2017-045 § 1 (Exh. A), 2017; Ord. 2019-013 § 1 (Exh. A), 2019)