Snohomish City Zoning Code

CHAPTER 14

255 Critical Areas Protection

14.255.010 Purpose.

The City of Snohomish is required by the Washington State Growth Management Act (Chapter 36.70A RCW) to designate environmentally critical areas and to adopt development regulations to assure the conservation of such areas. In compliance with this mandate, the City finds that environmentally critical areas characterize certain portions of Snohomish and its urban growth area. These critical areas include wetlands, habitat conservation areas, critical aquifer recharge areas, geologically hazardous areas, and frequently flooded areas. Accordingly, it is the purpose of the Critical Areas Code to:

A. Protect the functions and values of environmentally sensitive areas, while allowing for reasonable use of private property, through the application of the best available science.

B. Implement the Growth Management Act and the natural environment goals of the Comprehensive Plan.

C. Protect members of the public and public resources and facilities from injury, loss of life, or property damage due to landslides, steep slope failures, erosion, seismic events, or flooding.

D. Protect citizens and the unique, fragile, and valuable elements of the environment, including ground and surface waters, wetlands, anadromous fish species, and other fish and wildlife, and their habitats.

E. Prevent adverse and cumulative environmental impacts to critical areas, direct activities not dependent on critical area resources to less ecologically sensitive sites, and mitigate unavoidable impacts to critical areas by regulating alterations in and adjacent to critical areas and requiring specific mitigation measures to compensate for unavoidable impacts.

F. Protect species listed as threatened or endangered by the Washington Department of Fish and Wildlife (WDFW) or under the Federal Endangered Species Act of 1973 (16 USC 1531 through 1534) and their habitats.

G. Designate and protect environmentally sensitive and/or hazardous areas while accommodating growth and development needs through appropriate management and a science-based approach. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.020)

14.255.020 Critical Areas Code.

This chapter through Chapter 14.280 SMC shall collectively be known as the “Critical Areas Code.” This chapter shall establish the general framework for Chapters 14.260 through 14.280 SMC. The Planning Director shall administer and interpret the Critical Areas Code. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.030)

14.255.030 Best Available Science (BAS).

A. The City of Snohomish shall implement the use of best available science (BAS) in the application of the Critical Areas Code.

B. “Best available science” means information from research, inventory, monitoring, surveys, modeling, and an assessment, which is used to designate, protect, or restore critical areas.

C. As defined by WAC 365-195-900 through 365-195-925, best available science is derived from a process that includes peer-reviewed literature, standard methods, quantitative analysis and documented references to produce reliable information.

D. The use of best available science pursuant to the Critical Areas Code shall be consistent with the following:

1. Protection for Functions and Values and Anadromous Fish. Critical area reports and decisions to alter critical areas shall rely on the best available science to protect the functions and values of critical areas and must give special consideration to conservation or protection measures necessary to preserve or enhance anadromous fish and their habitat, such as salmon and bull trout.

2. Best available science to be used must be consistent with criteria. The best available science is that scientific information applicable to the critical area prepared by local, State or Federal natural resource agencies, a qualified scientific professional or team of qualified scientific professionals, which is consistent with criteria established in WAC 365-195-900 through 365-195-925.

3. Characteristics of a Valid Scientific Process. In the context of critical areas protection, a valid scientific process is one that produces reliable information useful in understanding the consequences of a local government’s regulatory decisions and in developing critical areas policies and development regulations that will be effective in protecting the functions and values of critical areas. The specific characteristics of a valid scientific process are as follows:

a. Peer Review. The information has been critically reviewed by other persons who are qualified scientific experts in that scientific discipline.

b. Methods. The methods used to obtain the information are clearly stated and reproducible. The methods are standardized in the pertinent scientific discipline or, if not, the methods have been appropriately peer-reviewed to assure their reliability and validity.

c. Logical Conclusions and Reasonable Inferences. The conclusions presented are based on reasonable assumptions supported by other studies and consistent with the general theory underlying the assumptions. The conclusions are logically and reasonably derived from the assumptions and supported by the data presented.

d. Quantitative Analysis. The data have been analyzed using appropriate statistical or quantitative methods.

e. Context. The information is placed in proper context. The assumptions, analytical techniques, data, and conclusions are appropriately framed with respect to the prevailing body of pertinent scientific knowledge.

f. References. The assumptions, analytical techniques, and conclusions are well referenced with citations to relevant, credible literature and other pertinent existing information.

E. Nonscientific Information. Nonscientific information may supplement scientific information, but it is not an adequate substitute for valid and available scientific information. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.035)

14.255.040 Applicability.

Unless exempted in SMC 14.255.050, the Critical Areas Code shall apply to all development within one or more of the critical areas identified in the following subsections or their associated buffers or building setback areas, regardless of whether the site has been previously identified as a critical area. Compliance with the provisions of this title does not constitute compliance with other Federal, State, and local regulations and permit requirements that may be required, including HPA permits, Army Corps of Engineers Section 404 permits, Ecology Section 401 permits, and NPDES permits. The applicant is responsible for complying with these requirements, apart from the process established in this title.

A. Wetlands as designated in Chapter 14.260 SMC;

B. Critical aquifer recharge areas as designated in Chapter 14.265 SMC;

C. Frequently flooded areas as designated in Chapter 14.270 SMC;

D. Geologically hazardous areas as designated in Chapter 14.275 SMC; and

E. Fish and wildlife habitat conservation areas as designated in Chapter 14.280 SMC. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.050)

14.255.050 Exemptions.

The following activities when occurring in critical areas shall be exempt from the Critical Areas Code; provided, that the activity must first be reviewed by the Planning Director to confirm that the exemption applies:

A. Emergency actions immediately necessary to prevent injury or property damage; provided, that the action minimizes impact to critical areas and buffers. The person undertaking the action shall notify the Planning Director within one working day following commencement of the emergency action. The Planning Director shall determine if the action was allowable under this subsection and commence enforcement if not. Within one year of the date of the emergency, the person undertaking the action shall fully mitigate any resulting impacts to the critical area and buffers in accordance with an approved critical area report and mitigation plan.

B. Normal operation, maintenance, or repair of existing structures, utilities, roads, levees, drainage systems, or similar improvements, including vegetation management, if the action does not alter or increase the impact to or encroach upon the critical area or buffer, and if the action accords with best management practices and maintenance and does not impact an endangered or threatened species.

C. Passive outdoor activities, such as recreation, education, and scientific research, that do not degrade the critical area.

D. Forest practices in accordance with Chapter 76.09 RCW and WAC Title 222, other than forest practice conversions.

E. Structural modifications of, additions to, or replacements of existing legal structures consistent with the provisions of SMC 14.255.060.

F. Within improved public rights-of-way or private street easements, construction, replacement, or modification of streets, utilities, lines, mains, equipment, or appurtenances, excluding electrical substations, are exempt from the first two “sequencing” methods stated in SMC 14.255.110(E); provided, that actions that alter a wetland or watercourse, such as culverts or bridges, or that result in the transport of sediment or increased stormwater shall be subject to the following requirements wherever possible:

1. Critical area and/or buffer widths shall be increased equal to the width of the right-of-way improvement, including disturbed areas; and

2. Native vegetation shall be retained and/or replanted, per the City of Snohomish plant material list, along the right-of-way improvement.

G. Minor public works projects, such as placement of a utility pole, street sign, anchor, or vault, which do not significantly impact critical areas function or values, if constructed using best management practices.

H. Removal with hand labor and light equipment of invasive or State recognized noxious weeds or plants, as designated by the Planning Director and including but not limited to:

1. English ivy (Hedera helix);

2. Himalayan blackberry (Rubus aremeniacus, R. bifrons);

3. Evergreen blackberry (Rubus laciniatus);

4. Bohemian knotweed (Polygonum x bohemicum); and

5. Scotch or Scot’s Broom (Sarothamnus scoparius).

I. Removal of trees consistent with the provisions of Chapter 14.120 SMC.

J. Measures to control fire or halt the spread of disease or damaging insects, consistent with the State Forest Practices Act, Chapter 76.09 RCW; provided, that the removed vegetation shall be replaced with the same or similar species within one year or species in accordance with City of Snohomish plant material list and an approved plan.

K. Application of herbicides, pesticides, or fertilizers, if necessary; provided, that their use shall conform to Washington State Departments of Ecology and Fish and Wildlife Management recommendations and the regulations of the Department of Agriculture and the U.S. Environmental Protection Agency and that written approval has been obtained from the Planning Director.

L. Minor clearing or digging necessary for surveys, soil logs, percolation tests, and similar activities; provided, that critical area impacts are minimized and disturbed areas are immediately restored.

M. Navigational aids and boundary markers.

N. Proposed developments that have undergone critical area review at a previous stage of permit review; provided, that the earlier permit has not expired and the proposed development has not significantly changed.

O. Harvesting of wild crops without injuring their natural reproduction, tilling the soil, planting crops, applying chemicals, or altering the critical area.

P. Conservation measures and restoration activities benefiting soil, water, vegetation, fish, and other wildlife that do not adversely impact ecosystems.

Q. Required environmental impact remediation.

R. Existing and ongoing agricultural activities, as defined in RCW 84.34.020(2), where the land has not lain idle for a period of five years or longer, so that modifications to the hydrological regime are necessary to resume operations.

S. Public Agency and Utility Exemption. If the application of this title would prohibit an activity or development proposal by a public agency or utility, the agency or utility may apply for an exemption pursuant to this section.

1. The public agency or utility shall apply to the Department and shall make available to the Department other related project documents such as permit applications to other agencies, special studies, and SEPA documents.

2. The Director may approve alterations to critical areas, buffers, and critical area setbacks by an agency or utility not otherwise allowed by this chapter when all of the following criteria are met:

a. There is no other feasible alternative to the activity or proposed development with less impact to the critical area, as documented through an assessment of adjustments in project footprint/orientation and modification to setbacks before encroaching into critical areas or their buffers.

b. The activity or development proposal is designed to avoid, minimize, and mitigate the impact to environmentally critical areas consistent with the avoidance and mitigation sequencing requirements in this chapter.

c. The proposed use does not pose a threat to the public health, safety, or welfare.

3. The Department will process exemptions, provide public notice, provide an opportunity for the public to request a public hearing, and provide an appeal process consistent with the provisions of Chapter 14.20 SMC. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.060)

14.255.060 Allowances for Existing Development.

The following developments, activities, and uses are allowed in critical areas and their associated buffers and building setbacks with the limitations of this section, provided such activities are otherwise consistent with this title and other applicable regulations. The Director may apply conditions to an underlying permit or approval to ensure that the activities are consistent with the provisions of this chapter.

A. If any existing, legally created single detached dwelling unit(s), accessory dwelling unit(s), accessory residential structure or outbuilding, commercial building, and/or associated impervious surfaces are located over or within a wetland, stream, or landslide hazard area, no further expansion within the wetland, stream, or landslide hazard area is allowed.

B. Maintenance of Existing Improvements. Existing single detached dwelling units, accessory structures, landscaping, and other existing uses and improvements that do not meet the requirements of this chapter but were legally established according to the regulations in place at their time of establishment may be maintained and no critical areas report or review is required, when the applicant has adequately demonstrated that there is no increase to existing uses and no net loss of existing critical area and critical area functions.

C. Change of Use and Existing Improvements. Approval of a preliminary subdivision, short subdivision or binding site plan shall require that an existing improvement or use that does not meet the requirements of this chapter be removed or discontinued prior to recording of the final plat, final short plat, or binding site plan in the following circumstances:

1. The existing improvement or use is located within critical areas or buffers. This includes, but is not limited to, an area proposed to be included in an averaged buffer; and

2. Removal of the existing improvement or use will result in a reduced impact to critical areas; or

3. One or more of the following criteria are met:

a. Removal or discontinuance of the existing improvement or use is necessary to meet water quality, drainage, or revegetation requirements or to qualify for incentives.

b. The existing improvement or use is no longer allowed in the zoning district or would be incompatible with a proposed use.

c. Removal or discontinuance of the existing improvement or use is necessary for public health, safety, or welfare, including but not limited to adequate sanitation, access, and/or safe walking conditions.

D. Modifications of Existing Improvements. Addition, expansion, reconstruction, or revision of existing building(s) or other structures is subject to the following:

1. Modification or Replacement. Structural modification or replacement of legally established structures that do not meet the building setback or buffer requirements is allowed if the modification or replacement does not increase the existing footprint of the structure lying within the critical area, buffer, or building setback area, and there is no increased risk to life or property.

2. Building Expansions in Low Density Residential Zones. Additions to and expansions of legally created dwelling unit(s), accessory dwelling unit(s), and associated impervious surfaces in the SFR and LDR zones that do not meet the applicable building setback or buffer requirements are allowed a one-time increase of up to 1,000 square feet added to the existing structure(s) and associated impervious surface areas lying within the buffer or building setback.

3. Building Expansions in Higher Intensity Zoning Districts. Structural modification of, addition to, or replacement of legally created buildings and associated impervious surfaces located in the COM, BP, HBD, IND, PIL, MID, MDR, and HDR zones that do not meet the applicable building setback or buffer requirements are allowed a one-time increase of up to 1,000 square feet or 10 percent of the subject property area, whichever is less, to the existing structure(s) and associated impervious surface areas lying within the buffer or building setback.

4. Conversions. Existing, legally established impervious surfaces with an approved stormwater system may be converted to a use that will not have more impact on the critical area, such as converting a parking lot to a building.

5. The provisions of this subsection are subject to the following and cannot be applied to development that was created through a reasonable use variance approval process:

a. Landslide Hazard Areas. If the existing legally created single detached dwelling unit(s) and/or accessory dwelling unit(s) and associated impervious surfaces are located within the building setback or buffer required for a landslide hazard area, a critical areas geotechnical report pursuant to the provisions of Chapter 14.275 SMC shall be submitted by the applicant and approved by the City that demonstrates there will be no increased risk to life or property by the proposed footprint expansion.

b. Aquatic and Habitat Resources. If an existing legally created single detached dwelling unit and/or accessory dwelling unit and associated impervious surfaces are located within the building setback or buffer for a wetland or within a FWHCA, the following must be met:

i. No portion of the addition or expansion may be located closer to the critical area than the nearest extent of the legally established existing single detached dwelling unit, except as provided under this section.

ii. Additions and expansions authorized under this subsection shall meet the following criteria:

A) A critical areas report approved by the City that demonstrates a net improvement in hydrologic and habitat values to the subject-affected critical area through restoration of degraded areas and/or buffer or through additional vegetated buffer; and

B) Mitigation of impacts to disturbed critical areas or buffers is provided in accordance with this chapter.

E. Reconstruction or replacement of the exterior footprint of an existing, legally established structure not meeting current regulations is allowed; provided, that the addition or reconstruction does not increase the degree of noncompliance. A critical areas report may be required by the Director. (Ord. 2533, 2025)

14.255.070 Critical Area Reports.

A. Unless waived by the Planning Director on the grounds that the specific information required in this section does not apply to the development in question, critical area reports shall be prepared for nonexempt proposed developments located within critical areas or their buffers.

B. All critical area reports shall:

1. Be prepared by qualified professionals as defined in WAC 365-195-905(4). The following list shows the type of critical area report and the related professional discipline. The list is illustrative and not intended to be inclusive.

a. Wetlands: qualified wetland professional.

b. Critical aquifer recharge areas: hydrogeologist, geologist, or engineer.

c. Floodplains: hydrologist or engineer.

d. Geologically hazardous areas: qualified geotechnical professional.

e. Fish and wildlife habitats: biologist.

2. Incorporate best available science.

3. Cover a study area large enough to understand relationships with important off-site factors and identify any off-site critical area so near that its required buffer covers part of the project site.

4. Include the following:

i. Name and contact information of the applicant;

ii. Name, qualifications, and contact information for the primary author(s) of the critical area report;

iii. Description of the proposed project;

iv. Identification of all the local, State and/or Federal permits required for the project; and

v. A vicinity map for the project;

b. Site plan drawn to scale showing critical areas, buffers, existing structures, and proposed structures, clearing, grading, and stormwater management;

c. Characterization of critical areas and buffers;

d. Assessment of the probable impact to critical areas;

e. Analysis of site development alternatives. If proposal requires a reduction of a buffer width, the analysis must explain why the need for the reduction was unavoidable;

f. Descriptions of efforts to avoid, minimize, and mitigate impacts to critical areas pursuant to SMC 14.255.110(E) (“sequencing”);

g. Mitigation plans as needed, in accordance with SMC 14.255.090;

h. Evaluation of compliance with this Critical Areas Code’s substantive requirements applicable to the proposed development;

i. A description of the financial guarantees, if any, that will be required to ensure compliance, pursuant to SMC 14.255.090(G)(1) and (G)(2);

j. Additional information as required in the chapter corresponding to the type of critical area;

k. Documentation of who performed the fieldwork and prepared data sheets and when the work was done;

l. Statement specifying the accuracy of the report and assumptions relied upon; and

m. Additional information as required by the Planning Director. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.060)

14.255.080 Previous Studies.

Critical area reports may rely upon, without duplication of effort, valid previous studies prepared for the site, taking into account any change in the site, the proposed development, or the surrounding area provided the previous studies have been reviewed by a qualified wetland professional and determined to be still valid or to reverify the study. The Planning Director, based on the qualified wetland professional’s determination and the City’s professional wetland consultant, may require an updated study or new delineation and assessment be made. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.070)

14.255.090 Mitigation Plan Requirements.

If the City allows conformance with this Critical Areas Code’s substantive requirements to be achieved by mitigation as provided for by this Code, a mitigation plan shall be required. The critical area report shall include a mitigation plan consisting of the following elements. Mitigation plans for specific critical areas, as described in Chapters 14.260 through 14.280 SMC, may require additional elements specific to those types of critical areas:

A. An analysis of the anticipated impacts;

B. A strategy for mitigating the impacts, including site selection factors;

C. An analysis of the anticipated functions and values that will result from the mitigation, including an assessment of risks;

D. A review of the best available science relative to the proposed mitigation;

E. Specific standards for evaluating whether the mitigation is successful;

F. Detailed construction plans, including:

1. Construction timing;

2. Grading and excavation details;

3. Erosion and sediment control features;

4. Planting plan; and

5. Measures to protect plants until established;

G. A program for monitoring the mitigation over at least five years; provided, that 10 years of monitoring may be required to ensure successful establishment of all trees and woody shrubs unless specifically stated otherwise in the chapter corresponding to the type of critical area. Sureties shall be required as described below to ensure compliance with the mitigation and monitoring program requirements. The monitoring program shall include information about the cost basis used to calculate surety amounts.

1. Performance Surety. All critical area mitigation and buffer enhancements shall be completed prior to final plat approval and/or building occupancy depending on the type of application. However, when improvement cannot be completed prior to final acceptance due to weather conditions which may negatively affect the success of the project, a performance surety may be used. The surety shall equal 150 percent of the cost of the mitigation project, and the required improvements shall be installed in a satisfactory manner within six months or less.

2. Maintenance Surety. A maintenance surety shall be required on all mitigation and enhancement projects to ensure that the improvement successfully survives the monitoring periods set above.

a. The amount of the maintenance surety shall be equal to 50 percent of the total cost of the mitigation plan as approved by the City.

b. The term of the surety shall reflect that of the approved monitoring program.

c. The amount of the surety may be reduced after year seven of the monitoring period if new cost estimates are provided and approved by the Planning Director;

H. Potential corrective measures should the monitoring indicate standards are not being met. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.080)

14.255.100 Independent Review of Critical Area Report.

The Planning Director may have the critical area report evaluated by an independent qualified professional and/or request consultation from a government agency with expertise. If the report and evaluations disagree, the Planning Director shall determine which to utilize, based on which is most consistent with the best available science. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.090)

14.255.110 Substantive Requirements.

A. All treatment of critical areas shall be in accordance with best available science as defined in WAC 365-195-900 through 365-195-925.

B. Critical areas and their buffers shall be left undisturbed, except that the following may be permitted if best management practices are used:

1. Authorized functional restoration or enhancement, including native vegetation associated with low impact development facilities, removal of invasive species, and trimming of significant trees in a manner consistent with best horticultural practices, that does not negatively impact the trees’ health and survivability;

2. In buffers: utility poles and utility lines which do not require excavation or clearing;

3. In the outer 50 percent of buffers: permeable-surfaced walkways, trails, and minimal wildlife viewing structures;

4. Developments for which mitigation is allowed per subsection E of this section; and

5. Other uses specifically authorized by the Critical Areas Code.

C. No development shall occur which results in a net loss of the functions or values of any critical area except reasonable use variances per SMC 14.255.130(B). The pre- and post-development functional comparison shall be on a per function basis unless otherwise authorized by the Critical Areas Code.

D. No development shall occur in critical areas and their buffers which results in an unreasonable hazard to the public health and safety.

E. These substantive requirements shall be met via one or more of the following methods, listed in preferential sequence (commonly known as “sequencing”). The methods used shall be those which are highest on the list yet consistent with the objectives of the proposed development:

1. Avoiding the impact altogether by not taking a certain action or parts of an action;

2. Minimizing impacts by limiting the degree or magnitude of the action and its implementation, by using appropriate technology, or by taking affirmative steps, such as project redesign, relocation, or timing, to avoid or reduce impacts;

3. Rectifying the impact to wetlands, critical aquifer recharge areas, frequently flooded areas, and habitat conservation areas by repairing, rehabilitating, or restoring the affected environment to the historical conditions or the conditions existing at the time of the initiation of the project;

4. Minimizing or eliminating the hazard by restoring or stabilizing the hazard area through engineered or other methods;

5. Reducing or eliminating the impact or hazard over time by preservation and maintenance operations during the life of the action;

6. Compensating for the impact to wetlands, critical aquifer recharge areas, frequently flooded areas, and habitat conservation areas by replacing, enhancing, or providing substitute resources or environments; and

7. Monitoring the hazard or other required mitigation and taking remedial action when necessary.

F. The City may allow reduction of buffer widths if steps are implemented to offset the negative impact of the reduction such as enhancement plantings, a proactive weeding program, placement of the buffer into a conservation easement or protected tract and if a qualified professional confirms in writing that functions and values of the critical area and buffer are not adversely affected.

G. Critical areas and buffers shall not be allowed within any lot of a subdivision and/or short plat unless the plat was vested prior to the effective date and implementation of the ordinance codified in this chapter. Subdivisions and/or short plats shall show, on their face, any applicable critical area limitations.

H. When any existing regulation, easement, covenant, or deed restriction conflicts with this Critical Areas Code, the one which provides more protection to the critical areas shall apply.

I. When critical areas of two or more types coincide, the more restrictive buffer and requirements shall apply.

J. Subject to approval through the planned residential development process, or approval by the Planning Director, depending on who the applicable decision-maker is, in calculating allowable residential units per acre, up to 100 percent of the acreage of critical areas and buffers may be counted and this density transferred to buildable portions of the site provided the overall density cap is not exceeded.

K. The substantive requirements unique to the type of critical area shall also be complied with, as set forth in the applicable chapter of the Critical Areas Code. (Ord. 2315, 2016; Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.100)

14.255.120 Critical Area Variances.

The City may grant variances from the Critical Areas Code’s substantive regulations in accordance with Chapter 14.70 SMC, if the variance request:

A. Conforms to the variance criteria stated in SMC 14.70.040;

B. Conforms with the purpose of the Critical Areas Code;

C. Does not impact anadromous fish habitat; and

D. Is justifiable in light of the best available science and the GMA policies referenced in SMC 14.255.010(G). (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.110)

14.255.130 Reasonable Use Variances.

A. Purpose. The standards and requirements of the Critical Areas Code are not intended and shall not be construed or applied in a manner to deny all reasonable use of private property. The purpose of a reasonable use variance is to ensure no private property owner is denied all reasonable use of their property. If an applicant demonstrates to the satisfaction of the Hearing Examiner that strict application of these standards would deny all reasonable use of a property, development may be permitted subject to appropriate conditions. A reasonable use variance is intended as a “last resort” when no plan and/or mitigation can meet the requirements of this chapter and allow the applicant a reasonable viable use of their property.

B. Approval Criteria. Reasonable use variances are processed as a Type 4 permit pursuant to SMC 14.20.020 and require all of the following criteria to be met:

1. That no reasonable use with less impact on the critical area and/or the buffer is feasible and reasonable;

2. There is no feasible and reasonable on-site alternative to the proposed activity or use that would allow reasonable use with less adverse impacts to the critical area and/or buffer. Feasible on-site alternatives shall include, but are not limited to:

a. Relocation of proposed structures;

b. Reduction in proposed density or building size;

c. Phasing of project implementation;

d. Change in timing of activities; and

e. Revision of road or parcel layout or related site planning considerations;

3. Any alterations permitted to the critical area or buffer shall be the minimum necessary to allow for reasonable use of the property and the project design must follow mitigation sequencing as outlined in SMC 14.255.110(E) and achieve no net loss of ecological functions; and any authorized alteration of a critical area under this subsection shall be subject to conditions established by the Department including, but not limited to, mitigation under an approved mitigation plan;

4. There are no practical alternatives available to the applicant for development of the property. An alternative is practical if the property or site is available and the project is capable of being done after taking into consideration existing technology, infrastructure, and logistics in light of the overall project purpose;

5. The proposed activity or use will be mitigated to the maximum practical extent and result in the minimum feasible alteration or impairment of functional characteristics of the site, including contours, vegetation and habitat, ground water, surface water, and hydrologic conditions, and consideration has been given to best available science;

6. There will be no material damage to nearby public or private property and no material threat to the health or safety of people on or off the property;

7. The proposed activity or use complies with all local, State, and Federal laws and the applicant has applied for or obtained all required State and Federal approvals; and

8. The inability to derive reasonable use is not the result of actions by the applicant.

C. Allowed Reductions for Single-Family Residential Reasonable Use Lots. Reasonable use variances shall allow the development of a modest (in terms of floor area, footprint size, height, and exterior amenities) single-family residential home and/or accessory dwelling unit located on a lot that is partially or completely within a critical area or its buffer.

1. Building setbacks, pursuant to Chapter 14.210 SMC, Dimensional Requirements, may be reduced by up to 50 percent where the applicant demonstrates to the City that the development cannot meet the City’s code requirements without encroaching onto a critical area or its buffer.

2. Development on single-family residential reasonable use lots shall:

a. Leave at least 70 percent of the lot undisturbed to protect the critical areas.

b. Have a maximum building footprint of 1,500 square feet.

c. Include the least amount of impervious area necessary to provide vehicular access provided it provides the shortest and most direct access to the house with minimal encroachment or impact into the critical area or buffer. When determining if the access has minimum encroachment or impact on a critical area the use of bridges and open bottom culverts shall be considered minimal impact.

d. Include yard areas only if they do not encroach into the critical area or buffer and do not require a buffer width reduction to accommodate the yard area.

D. Allowed Reductions for Multifamily, Commercial, and Industrial Reasonable Use Lots. Reasonable use variances shall allow for the economically viable development of lots with a land use designation of multifamily residential, commercial or industrial on a lot that is partially or completely within a critical area or its buffer.

2. For commercial and industrial projects, the number of required parking stalls may be reduced by up to 40 percent if the applicant can demonstrate that the reduction would not negatively affect the business or create spillover parking onto City streets.

E. Reasonable use lots shall not be subdivided unless there is sufficient area to construct all buildings, driveways, landscaping, and yard areas without intruding on the critical area or buffer. (Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.120)

14.255.140 Critical Area Protection Methods.

The City may require the following methods as a condition of any permit approval, code enforcement remediation, or as mitigation for individual actions that affect a critical area:

A. Native Growth Protection Areas (NGPAs). NGPA easements or tracts contain critical areas, buffers, or both, and are permanently protected from disturbance. NGPAs shall be recorded with the Snohomish County Auditor with any specific provisions or conditions.

1. NGPAs must be recorded on all documents of title of record for all affected lots.

2. NGPAs shall be held by the City, a homeowner’s association, a land trust, or similar conservation organization, or by each lot owner within the development in an undivided interest.

3. NGPAs must be designated on the face of the plat or recorded drawing in a format approved by the City Attorney. The designation must include the following restrictions:

a. An assurance that native vegetation is to be preserved for the purpose of preventing harm to property and the environment, including, but not limited to, controlling surface water runoff and erosion, maintaining slope stability, buffering, and protecting plants, fish, and animal habitat.

b. The right of the City to enforce the terms of the restriction.

4. The outer perimeter of the NGPA shall be delineated on the ground in accordance with local survey standards and marked with permanent signs.

5. Signs shall be made of an enamel-coated face and affixed to split-rail fencing, attached to a metal post, an untreated four-by-four wooden post, or another nontreated material of equal durability;

a. Posted at an interval of one every 50 feet, or one per lot if the lot is less than 50 feet wide;

b. Located at least four feet above the ground;

c. At least eight inches wide and 12 inches tall;

d. Maintained by the property owner in perpetuity; and

e. Worded as following or with alternative language as allowed by the Planning Director:

Native Growth Protection Area
This critical area and buffer is protected to provide wildlife habitat, maintain water quality, or to protect public health and safety. Please do not disturb this valuable resource.
Contact the City of Snohomish Planning & Development Services Department regarding uses and restrictions.

f. The provisions of this subsection may be modified as necessary to assure protection of sensitive features or wildlife.

6. Permanent fencing shall be installed around the outer perimeter of the NGPA to delineate the protected area, meeting all the requirements of subsection B of this section.

1. The fence shall be a split rail fence no more than four feet high or similar design as approved by the Director or designee.

2. An alternate fence type may be approved if the use adjacent to the critical area or NGPA necessitates increased security or safety, as approved by the Director.

3. When domestic grazing animals are present or may be introduced on site, the required permanent fence around the edge of the buffer shall be of construction adequate to prevent the domestic grazing animals from entering the protected area.

4. Fencing installed as required in this subsection shall be designed so as to not interfere with species migration, including fish runs, and shall be constructed in a manner that minimizes impacts to the wetland and associated habitat.

C. Notice on Title. To inform subsequent purchasers of real property of the existence of critical areas, the City may require as a condition of development for any property containing a critical area or buffer a notice to be filed on title with the County Records and Elections Division against the subject property.

1. The notice must state the presence of the critical area or buffer on the property, the application of this chapter to the property, and the fact that limitations on actions in or affecting the critical area or buffer may exist.

2. The notice on title is not required for a development proposed by a public agency or public or private utility.

3. The applicant shall submit documentation that the notice has been filed for public record before any permit may be issued for the property or, in the case of land divisions, at or before recording. (Ord. 2533, 2025)

14.255.150 Enforcement and Inspections.

In enforcing violations of the Critical Areas Code per Chapter 14.85 SMC, the Planning Director may require a restoration plan prepared by a qualified professional. Historic functions and values, soil configurations, and native vegetation shall be used as a guide for restoration. Flood and geological hazards shall be reduced to the predevelopment level.

Reasonable access to the development shall be provided to agents of the City for critical area inspections, monitoring, restoration, or emergency action. (Ord. 2083, 2005; Ord. 2368, 2019; Ord. 2533, 2025. Formerly 14.255.130)

Snohomish City Zoning Code

CHAPTER 14

255 Critical Areas Protection

14.255.010 Purpose.

A. Protect the functions and values of environmentally sensitive areas, while allowing for reasonable use of private property, through the application of the best available science.