Chapter 15.16
GRADING AND EXCAVATION
Sections:
15.16.040 Permit required—Application.
15.16.090 Security requirement.
15.16.100 Contractor requirements.
15.16.150 Drainage and terracing.
15.16.170 Clearing and grading inspection.
15.16.010 Purpose.
A. The purpose of this chapter is to promote, protect and preserve the public interest by regulating land alteration, particularly the clearing and grading of land in the city.
B. This chapter is necessary in order to:
1. Provide minimum development regulations and construction procedures which will preserve, replace or enhance to the maximum extent practicable, consistent with the zoning and subsequent development of the land, evergreens, specimen deciduous trees, understory and groundcover within the city;
2. Minimize water quality degradation and the sedimentation of creeks, streams, ponds, lakes, wetlands and other water bodies;
3. Minimize the impact of increased runoff erosion and sedimentation on nonconsenting persons caused by improper land development and maintenance practices;
4. Maintain and protect ground water resources; to minimize adverse effects of alteration in ground and surface water quantities, locations, and flow patterns;
5. Promote safety upon city roads and rights-of-way; to decrease potential landslide, flood, and erosion damage to public and private property; and
6. Promote site planning and building practices which are consistent with the city’s natural topographical, vegetational and hydrological features.
C. This chapter is intended to promote the health, safety and welfare of the public and nothing in this chapter is intended to or shall be deemed to create a duty in the city to protect or promote the interests of any particular person or class of persons. The existence of these regulations or any failure, refusal or omission of the city to enforce any provision in this chapter shall not prevent, supplant or affect the right of any person affected by the clearing and grading operations of another to invoke such private remedies as may be available against such other person. (Ord. 1493 § 7, 2024; Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 1173 § 6 (part), 2007; Ord. 602 (title), § 1, 1988)
15.16.020 Definitions.
Words and phrases when used in this chapter shall have the meanings as defined in Chapter 17.08, Definitions. Words not defined shall have their usual meanings as commonly understood. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 2, 1988)
15.16.030 Permit authority.
The director of the public works department or a designee, hereinafter termed the permit authority, is the designated agent for the issuance of clearing and grading permits. The permit authority shall have the authority to develop administrative procedures to carry out the purposes and intent of this clearing and grading code. Such administrative procedures should be developed in consultation with technical advisors as circumstances require and shall be made available to the public for comment at least seventeen days before adoption. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 3, 1988)
15.16.040 Permit required—Application.
No person shall make changes or cause changes to be made in the surface of any land by grading, excavating, or the removal or disturbance of the natural topsoil, trees, or other vegetative covering thereon without first having obtained a valid clearing and grading permit, except as provided in the exemptions following:
A. Agricultural crop management;
B. Cemetery grave;
C. Routine landscape maintenance;
D. Landscape installation where fill is confined to less than one foot of topsoil or landscape berms not exceeding four feet in height and fifty cubic yards in volume with side slopes flatter than three feet horizontal to one foot vertical (thirty-three percent) and not subject to the special conditions of subsection I of this section;
E. Emergency situations involving immediate danger to life or property or substantial fire hazards;
F. An excavation of less than fifty cubic yards of material which:
1. Is less than one foot in depth; or
2. Which does not create a cut slope greater than five feet in height and steeper than two horizontal to one vertical (fifty percent);
G. A fill less than one foot in depth and placed on natural terrain with a slope flatter than five horizontal to one vertical (twenty percent) or a fill less than three feet in depth and not intended to support structures, which does not exceed fifty cubic yards on any one lot and does not obstruct a stream or surface water;
H. A clearing less than one thousand square feet where the existing zoning is single-family residential. Only one exempted clearing or grading operation per site shall be permitted under the exception provided in this subsection;
I. Except for subsections A, C and E of this section, not more than one of the exemptions set forth in this section shall apply on one designated site. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 4, 1988)
15.16.050 Requirements.
It is the intent of this section to promote practices consistent with the city’s natural topographic, vegetational, and hydrologic features, and to control substantial land alterations of a speculative nature. In considering whether to issue a permit, and in considering whether and what type of conditions should be imposed, the permit authority shall apply the following standards and criteria:
A. General. A clearing and grading permit shall be issued only in conjunction with one or more of the following:
1. A valid building permit;
2. Utility extension;
3. A valid permit(s) to build a property access road;
4. Approved permit for street, water, storm and sanitary sewer construction for a preliminary plat;
5. Approved short plat;
6. Special permission of the permit authority for site work less than or equal to five hundred cubic yards based on a demonstration that extenuating circumstances are present and that the project is consistent with the grading and drainage plan with landscaping, soil stabilization and surface groundcover elements including continuous maintenance;
7. For site work over five hundred cubic yards, the purpose of which is not to achieve approval or development under subsections (A)(1) through (5) of this section.
a. Decision Criteria. The permit authority may approve or approve with modifications an application submitted under this subsection only if:
i. The proposal is in accord with the comprehensive plan, comprehensive stormwater plan, zoning code, stormwater management code and other city codes and adopted standards,
ii. The approval of the proposal will not pose a threat to or be detrimental to the public health, safety and welfare, and
iii. The applicant has demonstrated that approval of the proposal is necessary for the reasonable development or maintenance of the property;
b. Time Limits May Be Imposed. For any permit authorized under this subsection the permit authority may impose a time limit within which the proposed site work must be completed, generally not to exceed one year.
B. Hazards. Whenever the permit authority determines that any existing excavation or embankment or fill on private property has become a hazard to life and limb, or endangers property, or adversely affects the safety, use or stability of a public way or drainage channel, the owner of the property upon which the excavation or fill is located, or other person or agent in control of the property, upon receipt of notice in writing from the permit authority, shall within the period specified therein repair or eliminate such excavation or embankment so as to eliminate the hazard and be in conformance with the requirements of this code.
C. Clearing.
1. All clearing of vegetation shall conform to the specifications of this table, except as noted elsewhere in this subsection:
|
Table 1: Clearing Matrix 2a |
||
|---|---|---|
|
Grade of Site or Slope (%) |
Maximum Native Vegetation/Groundcover Removal (%) |
Minimum Required Significant Tree Retention (%) |
|
> 35% 2b |
|
See notes. |
|
> 25%—≤ 35% |
45% |
55% |
|
> 15%—≤ 25% |
60% |
40% |
|
≤ 15% |
75% |
25% |
2. Table Notes.
a. Clearing shall not affect critical root zone around retained trees. Fencing shall be used as protection, as found in the development standards. Storage and staging of heavy machinery and parking are not allowed on critical root zones.
b. Applications for clearing and grading on slopes in excess of thirty-five percent shall be accepted in those cases where tree removal is limited to pruning (provided survival is assured). Clearing or grading on slopes in excess of thirty-five percent may be allowed upon prior review and approval by the permit authority, to the extent permitted by this subsection (C)(2)(b). In addition to any other information that may be required, the applicant shall provide the following:
i. Slope Report. The slope report shall be prepared by a qualified professional. The required slope report shall contain the following information, including recommended methods for mitigating identified impacts and a description of how these mitigating measures may impact adjacent property:
(a) Soils Report. Investigation and report shall be prepared by or under the supervision of a civil engineer with a soil/geotechnical expertise, licensed by the state of Washington and acceptable to the city. This report shall include data regarding the nature, distribution and strength of existing soils and the characteristics of the underlying geology, infiltration rates, conclusions and recommendations for grading procedures, design criteria for corrective measures and opinions and recommendations covering the carrying capabilities of the site. The applicant shall indicate location of soils that should remain undisturbed or used for stormwater management purposes during the time of construction;
(b) Hydrology Report. The investigation and report shall be prepared by a qualified professional hydrologist acceptable to the city. This report shall include an adequate description of the hydrology of the site, conclusions and recommendations regarding the effect of hydrologic conditions on the proposed development and options and recommendations covering the carrying capabilities of the sites to be developed.
ii. Grading Plan. The grading plan shall be prepared by a qualified professional. The report shall include a schedule showing when each stage of the project will be completed, including the total area of soil surface which is to be disturbed during each stage and the estimated starting and completion dates; the schedule shall be drawn up to limit to the shortest possible period the time that soil is exposed and unprotected. In no event should the existing vegetative groundcover be destroyed, removed or disturbed more than fifteen days prior to development.
iii. Revegetation Plan. A revegetation report shall be provided which shall be prepared by or under the supervision of a landscape architect licensed by the state of Washington who is acceptable to the city and shall include the following:
(a) Measures to be taken for slope stabilization and erosion control;
(b) Measures to be taken for protection and replacement of the native vegetative cover;
(c) A schedule showing when each stage of the project will be revegetated with estimated starting and completion dates and such other information as may be required by the city.
iv. The city may retain a qualified licensed professional in any of the above specialties, licensed to practice in the state of Washington, at the expense of the applicant, to review and confirm the applicant’s reports, studies, and plans. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 1308 § 3, 2012; Ord. 665 § 1, 1990; Ord. 602 § 5, 1988)
15.16.060 Permit—Application.
A. Application. To obtain a permit, the applicant shall first file an application in writing on a form furnished for that purpose. Every such application shall:
1. Identify the responsible person for the permit and include the address and phone number(s) of the same;
2. Identify and describe the work to be covered by the permit for which application is made;
3. Describe the site on which the proposed work is to be done, by legal description, by lot, block, tract, or house and street address, or similar description that will readily identify and definitely locate the proposed building or work;
4. Indicate the use or occupancy for which the proposed work is intended;
5. Estimate the quantities of work involved;
6. Be accompanied by plans and specifications as required in subsection C of this section unless short-form application is made according to subsection B of this section;
7. State the valuation of the proposed work;
8. Be signed by the permittee, or his authorized agent, who may be required to submit evidence to indicate such authority;
9. Give such other information as reasonably may be required by the permit authority.
B. Plans and Specifications. Each application for a permit shall be accompanied by three plan sets and specifications. The permit authority may require, as supporting data, one or more reports covering soils engineering, engineering geology and hydrology, and an environmental checklist. The plans and specifications shall be prepared and sealed by a registered professional engineer when required by the permit authority.
C. Information on Plans and in Specifications. Plans shall be drawn to a scale of not more than one inch equals fifty feet upon reproducible media and shall be of sufficient clarity to indicate the nature and extent of the work proposed and show in detail that they conform to the provisions of this chapter. The plans shall include the following information:
1. The first sheet of each set of plans shall give:
a. The correct legal description of the property;
b. The name(s), address(es) and phone number(s) of the owner(s) of the land and the person(s) ordering the work to be performed;
c. The total clearing to be performed in acres;
d. The total impervious surface to be created in acres;
e. The estimated total amount of excavation to be performed in cubic yards;
f. The estimated total amount of fill to be performed in cubic yards;
g. The name(s), address(es), phone number(s) and seal, if registered, of professional(s) preparing the plans;
h. The name(s), address(es) and phone number(s) of professional(s) preparing the soils engineering, engineering geology, and/or hydrology reports, when such reports are required;
i. A general vicinity map to scale showing the site and all streets within three hundred feet, together with the names, addresses and locations of abutting landowners, as shown by Snohomish County assessor’s records.
2. An accurate plan of the entire site as it exists at the time of the application showing the following minimum information:
a. Topography, taken at not more than a five-foot contour interval over the entire site. Ninety percent of the contours shall be plotted within one-half of a contour interval and the remainder within one contour of the true location. Aerial compilation methods are acceptable; however, all areas obscured by vegetation shall be checked and verified by on-site measurements;
b. Five-foot contour intervals that extend a minimum of two hundred feet off site, when available;
c. All property lines shown in true location with respect to the plan’s topographic information;
d. A copy of a current, generally available aerial photo of the site with property lines;
e. A graphic representation of existing vegetation on the site delineating vegetation boundaries, predominant types (common names) and approximate density of cover according to the following categories:
i. Bare ground: no existing vegetation;
ii. Groundcover: up to or equal to one foot in height;
iii. Brush: greater than one foot up to or equal to four feet in height;
iv. Understory: greater than four feet up to or equal to ten feet in height;
v. Overstory: greater than ten feet in height;
vi. Impervious: rock, artificial condition;
f. A tree retention plan showing any significant trees that shall be retained or removed. The applicant shall also identify limits of full tree dripline of the canopy and limits of critical root zones. The plan shall identify measures to be taken to protect trees during construction such as fencing of trees, and avoiding disturbance of critical root zones. Tree retention plans shall also identify how requirements set in Section 15.16.050(C)(2)(a) are met, when applicable;
g. Location of all existing drainage facilities which transport surface water onto, across, or from the site including: streams and surface waters, artificial channels, drain pipe or culverts;
h. Location and estimated capacity of all natural or artificial basins which impound surface water;
i. Location and estimated capacity of all visible springs in excess of one gallon per minute;
j. Location and elevations of all buildings, structures, utilities or other appurtenances on the property where the work is to be performed and the location of any buildings or structures on land of adjacent owners which are within fifteen feet of the property.
3. An accurate plan of the entire site as it will appear after construction showing the following minimum information:
a. Limiting dimensions, elevations or finished contours to be achieved by the grading;
b. Location and capacity of all drainage facilities and related construction;
c. Boundaries of all areas to remain in the existing or natural condition;
d. Location of all vegetation shown on the plan which will remain after completion of the work and at the minimum distance to the nearest excavation and/or filling;
e. Boundaries of all areas that will be paved or otherwise altered in a manner that will increase stormwater runoff;
f. Boundaries of all areas in which the infiltration capacity of the soil will be retained and/or improved;
g. Method of discharging stormwater off-site at the naturally occurring location together with the provisions needed to restrict the velocity and direction of the discharge in order to avoid damage to other properties;
h. Detailed plans of all surface and subsurface drainage devices, walls, cribbing, dams and other protective devices to be constructed with or as a part of the proposed work;
i. Methods of preventing sediment or other pollution from leaving the site during and after construction; i.e., an erosion control plan, and their timing of installation.
D. The permit authority may require additional information when the permit authority finds that the submitted plans, specifications and other data are not sufficiently clear to allow a determination that the proposed work fully conforms to this section, or if there is reasonable cause to believe that the proposed clearing or grading will have a significant effect upon other properties. This information may consist of but is not necessarily limited to any of the following:
1. Calculations of the expected peak runoff of stormwater both reaching and leaving the site for the then existing conditions of the area tributary to the site and ultimate watershed development based upon the current comprehensive land use plan, as now existing or as hereafter amended. If water is to be impounded during construction or as part of the final plan of the site development, inflow-outflow hydrographs shall be plotted for the return period storms showing the impounded volume and maximum discharge.
2. A scaled drawing showing cross-sections of the channel and/or pipe at both upstream and downstream property lines with the elevations of the water surface shown for the specified return period storms thereon for the then existing conditions.
3. A soil engineering report which shall include data regarding the nature, distribution, and strength of existing soils, conclusions and recommendations for clearing and grading procedures, and design criteria for corrective measures when necessary; together with opinions and recommendations covering adequacy of sites to be developed and the extent of significant effects of the site development upon surrounding properties by the proposed clearing and grading. Recommendations included in the report shall be incorporated in the clearing and grading plan, specifications, or support material.
4. A soil management plan consisting of information of how soil disturbance will be minimized or how native soils will be retained or restored. The soil management plan shall include:
a. Map of soil protection areas, areas to be disturbed, access roads, locations of material storage, permanent infiltration facilities, and soil enhancement areas.
b. A narrative describing measures to be taken either for protection or restoration of functional topsoil conditions (minimum twelve inches deep) over the entire site, including:
i. How protection areas and soil enhancement areas will be protected from compaction.
ii. How disturbed soils will be improved and revegetated.
iii. Treatment details for each area scheduled for soil enhancement (disturbed soil areas) and calculations of the quantities of compost and/or compost-amended topsoil and mulch that will be used to meet the provisions of BMP T5.13 of the Ecology Manual.
iv. Additional information describing how plan is in accordance with BMP T5.13 of the Ecology Manual.
5. An engineering geology report which shall include an adequate description of the geology of the site, conclusions and recommendations regarding the effect of geologic conditions on the proposed development, and opinions and recommendations covering the adequacy of sites to be developed and the extent of significant effects of the site development upon surrounding properties by the proposed clearing and grading. Recommendations included in the report shall be incorporated in the plans, specifications or support material.
6. A hydrology report which shall include an adequate hydrology study of the drainage basin in which the development site is located, conclusions setting forth existing and future changes in the hydrology and the extent of significant effects on the surrounding and downstream properties as a result of the proposed clearing, grading and development and design criteria for corrective measures whenever necessary, together with opinions and proposed project conditions. Recommendations included in the report shall be incorporated in the plans, specifications, or support material.
7. Additional reports may be required, if, in the judgment of the permit authority, such information is deemed advisable, including but not limited to biological, wildlife, chemical, water quality, bacterial or other factors related to environmental impact. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 6, 1988)
15.16.070 Permit—Fees.
Before accepting a set of plans and specifications for checking, the permit authority or his/her designee shall collect a permit fee. Such fee shall be determined according to a standard fee schedule approved by the city council by resolution adopted and reviewed from time to time. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 7 (part), 1988)
15.16.080 Permit—Expiration.
The expiration of clearing and grading permits and applications shall be valid for the same time period as the primary development permit; provided, however, that the permit authority may set specific limits to the permit for project initiation and/or completion for environmental reasons or for coordination with other permitted site work. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 7 (part), 1988)
15.16.090 Security requirement.
A. The permit authority may require the applicant to establish a security in the form of cash escrow account or an irrevocable letter of credit or other form of credit which may be acceptable to the city, at its sole discretion, with his bank in an amount deemed by the permit authority to be sufficient to reimburse the city if it should become necessary for the city to enter the property for the purpose of correcting and/or eliminating hazardous conditions relating to soil stability and/or erosion, or to restore vegetation, and/or for other purposes authorized in this chapter.
B. In no case shall the security be less than the permit authority’s estimate of the cost of correcting or eliminating hazardous conditions that reasonably may occur, and/or of insuring compliance with the stipulations of the permit and the approved plans and specifications. In addition, security may be required to protect the city from potential damage claims and/or other damage to city streets, utilities or property in the same manner and extent as may be required prior to issuance of a building permit pursuant to other sections of this code.
C. Should the city, during the course of construction, find it necessary to expend the security to correct any work not in accordance with the approved plans and specifications, a stop work order shall be issued to the permittee on any additional work until the security is reestablished by the permittee. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 8, 1988)
15.16.100 Contractor requirements.
Every contractor or other person performing or directing the performance of any work requiring a permit under this chapter shall have in his/her possession prior to commencement of and during all phases of the work an original or copy of a valid permit therefor, and shall further have a duty to be familiar with the terms and conditions of the permit and approved plans and specifications. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 9, 1988)
15.16.110 Project inspection.
A. General. All projects which include clearing and grading shall be subject to inspection by the permit authority or his designee. The permit authority or his designee shall be granted unlimited right of entry to the worksite by the application for the purposes of making inspections to determine that the requirements of the plans and permits are being complied with, and for the purposes of taking corrective measures of an emergency nature. The cost of such corrective measures shall be borne by the applicant. The permit authority may require inspection and testing by an approved testing agency at any stage of the application or project.
B. It shall be the permittee’s responsibility to notify the permit authority or his designee at least twenty-four hours prior to the time required for inspection. If the permit authority fails to inspect the project within eight working hours after the scheduled inspection time, the permittee may proceed with the project but shall not be relieved from compliance with the requirements of the plans, specifications, and permit as approved. All inspections and testing required shall be determined prior to issuance of the permit, except those that may be required when conditions exist that were not covered in the documents submitted when requesting a permit. The permit authority may require additional inspection or testing if conditions are found to be different than those presented in the plans or supporting documents; however, if and when conditions change, it shall be the responsibility of the applicant or the professional consultants who submitted the plans or documents to provide the permit authority with recommended changes to procedures, for its review and approval.
C. Suspension of Permits. Whenever the permit authority determines that the act or intended act of clearing, grading, excavation or fill has become or will constitute a hazard to life and limb, or endangers property, or adversely affects the safety, use or stability of a public way, drainage channel, stream or surface water, including siltation and sedimentation therein, the permit authority shall immediately suspend the clearing and grading permit. The permittee or other person or agent in control of the property, upon receipt of notice in writing from the permit authority shall, within the period specified therein, terminate such clearing, grading, excavation, embankment or fill, or eliminate the same from the development plans. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 10, 1988)
15.16.120 Cuts.
A. General.
1. Unless otherwise recommended in the approved soils engineering and/or engineering geology report, cuts shall conform to the provisions of this section.
2. In the absence of an approved soils engineering report, these provisions may be waived for minor cuts not intended to support structures.
B. Slope. The slope of cut surfaces shall be no steeper than is safe for the intended use and shall be no steeper than two horizontal to one vertical (fifty percent) unless the owner furnishes a soils engineering or an engineering geology report, or both, stating that the site has been investigated and giving an opinion that a cut at a steeper slope will be stable and not create a hazard to public or private property. The report shall be reviewed and approved by the city engineer prior to earth work.
C. Drainage and Terracing. Drainage and terracing shall be provided as required. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 11, 1988)
15.16.130 Fills.
A. General.
1. Unless otherwise recommended in the approved soils engineering report, fills shall conform to the provisions of this section.
2. In the absence of an approved soils engineering report, these provisions may be waived for minor fills not intended to support structures.
B. Fill Location. Fill slopes shall not be constructed on natural slopes steeper than two horizontal to one vertical (fifty percent).
C. Preparation of Ground. The ground surface shall be prepared to receive fill by removing vegetation, noncomplying fill, topsoil and other unsuitable materials, scarifying to provide a bond with the new fill and, where slopes are steeper than five horizontal to one vertical (twenty percent) and the height is greater than five feet, by benching into sound bedrock or other competent material as determined by the soils engineer. The bench under the toe of a fill on a slope steeper than five horizontal to one vertical (twenty percent) shall be at least ten feet wide. The area beyond the toe of fill shall be sloped for sheet overflow or a paved drain shall be provided. When fill is to be placed over a cut, the bench under the toe of fill shall be at least ten feet wide but the cut shall be made before placing the fill and acceptance by the soils engineer or engineering geologist or both as a suitable foundation for fill.
D. Fill Material.
1. Organic material shall not be permitted in fills. Except as permitted by the building official, no rock or similar irreducible material with a maximum dimension greater than twelve inches shall be buried or placed in fills.
2. Exceptions. The permit authority may permit placement of larger rock when the soils engineer properly devises a method of placement, continuously inspects its placement and approves the fill stability. The following conditions shall also apply:
a. Prior to issuance of the grading permit, potential rock disposal areas shall be delineated on the grading plan.
b. Rock sizes greater than twelve inches in maximum dimension shall be ten feet or more below grade, measured vertically.
c. Rocks shall be placed so as to assure filling of all voids.
E. Compaction. All fills shall be compacted to a minimum of ninety percent of maximum density as determined by the IBC. In-place density shall be determined in accordance with the IBC.
F. Slope. The slope of fill surfaces shall be no steeper than is safe for the intended use. Fill slopes shall be no steeper than two horizontal to one vertical (fifty percent).
G. Drainage and Terracing. Drainage and terracing shall be provided and the area above fill slopes and the surfaces to terraces shall be graded and paved as required. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 12, 1988)
15.16.140 Setbacks.
A. General. Cut and fill slopes shall be set back from site boundaries in accordance with this section. Setback dimensions shall be horizontal distances measured perpendicular to the site boundary. Setback dimensions shall be shown in accordance with Appendix J of the International Building Code as adopted in Section 15.04.040.
B. Top of Cut Slope. The top of cut slopes shall be made not nearer to a site boundary line than one fifth of the vertical height of cut with a minimum of two feet and a maximum of ten feet. The setback may need to be increased for any required interceptor drains.
C. Toe of Fill Slope. The toe of fill slope shall be made not nearer to the site boundary line than one-half the height of the slope with a minimum of two feet and a maximum of twenty feet. Where a fill slope is to be located near the site boundary and the adjacent off-site property is developed, special precautions shall be incorporated in the work as the permit authority deems necessary to protect the adjoining property from damage as a result of such grading. These precautions may include but are not limited to:
1. Additional setbacks;
2. Provision for retaining or slough walls;
3. Mechanical or chemical treatment of the fill slope surface to minimize erosion;
4. Provisions for the control of surface waters.
D. Modification of Slope Location. The permit authority may approve alternate setbacks. The permit authority may require an investigation and recommendation by a qualified engineer or engineering geologist to demonstrate that the intent of this section has been satisfied. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 1173 § 6 (part), 2007; Ord. 602 § 13, 1988)
15.16.150 Drainage and terracing.
A. General. Unless otherwise indicated on the approved clearing and grading plan, drainage facilities and terracing shall conform to the provisions of this section for cut or fill slopes steeper than three horizontal to one vertical (thirty-three percent).
B. Terrace.
1. Terraces at least six feet in width shall be established at not more than thirty-foot vertical intervals on all cut or fill slopes to control surface drainage and debris except that where only one terrace is required, it shall be at mid-height. For cut or fill slopes greater than sixty feet and up to one hundred twenty feet in vertical height, one terrace at approximately mid-height shall be twelve feet in width. Terrace widths and spacing for cut and fill slopes greater than one hundred twenty feet in height shall be designed by the civil engineer and approved by the permit authority. Suitable access shall be provided to permit property cleaning and maintenance.
2. Swales or ditches on terraces shall have a minimum gradient of five percent and must be paved with reinforced concrete not less than three inches in thickness or an approved equal paving. They shall have a minimum depth at the deepest point of one foot and a minimum paved width of five feet.
3. A single runoff swale or ditch shall not collect runoff from a tributary area exceeding thirteen thousand five hundred square feet (projected) without discharging into a down drain.
C. Subsurface Drainage. Cut and fill slopes shall be provided with subsurface drainage as necessary for stability.
D. Disposal.
1. All drainage facilities shall be designed to carry water to the nearest practicable drainage way approved by the permit authority. Erosion of ground in the area of discharge shall be prevented by installation of nonerosive down drains or other devices.
2. Building pads shall have a drainage gradient of two percent toward approved drainage facilities, unless waived by permit authority.
3. Exception. The gradient from the building pad may be one percent if all of the following conditions exist throughout the permit area:
a. No proposed fills are greater than ten feet in maximum depth.
b. No proposed finish cut or fill slope faces have a vertical height in excess of ten feet.
c. No existing slope faces, which have a slope face steeper than ten horizontal to one vertical (ten percent), have a vertical height in excess of ten feet.
E. Permanent Interceptor Drains. Paved interceptor drains shall be installed along the top of all cut slopes where the tributary drainage area above slopes towards the cut and has a drainage path greater than forty feet measured horizontally. Interceptor drains shall be paved with a minimum of three inches of concrete, or an approved equivalent, and reinforced. They shall have a minimum depth of twelve inches and a minimum paved width of thirty inches measured horizontally across the drain. The slope of drain shall be approved by the permit authority. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 14, 1988)
15.16.160 Erosion control.
A. Slopes. The faces of cut and fill slopes shall be prepared and maintained to control against erosion. This control may consist of effective planting. The protection for the slopes shall be installed as soon as practicable and prior to calling for final approval. Where cut slopes are not subject to erosion due to the erosion-resistant character of the materials, such protection may be omitted.
B. Other Devices. Where necessary, check dams, cribbing, riprap or other devices or methods shall be employed to control erosion and provide safety.
C. Sequencing. A sequencing schedule shall be provided for any construction project to address timing of land-disturbing activities during periods when soils are most exposed to erosion from wind, rain, runoff, and vehicle tracking. If a summer project is extended into the wet season (October 1st to April 30th), a wet weather erosion control plan shall be provided on or before September 1st for review and approval.
D. Wet Weather Erosion Control Plan. Clearing and grading in the wet months (October 1st to April 30th) shall only be allowed with the approval of a wet weather construction plan implementing the best management practices in the Ecology Manual and the development standards. The wet weather construction plan shall be completely and fully implemented by the developer. Requirements of the wet weather construction plan shall meet all the standards and requirements of the development standards. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 1124 § 1, 2005; Ord. 602 § 15, 1988)
15.16.170 Clearing and grading inspection.
A. General. All grading operations for which a permit is required shall be subject to inspection by the permit authority. When required by the permit authority, special inspection of grading operations and special testing shall be performed in accordance with the provisions of Appendix J of the International Building Code as adopted in Section 15.04.040.
B. Grading Designation. All grading in excess of five thousand cubic yards shall be performed in accordance with the approved grading plan prepared by the civil engineer, and shall be designated as “engineered grading.” Grading involving less than or equal to five thousand cubic yards shall be designated “regular grading” unless the permittee, with the approval of the permit authority, chooses to have the grading performed as “engineered grading.”
C. Engineered Grading Requirements.
1. For engineered grading, it shall be the responsibility of the civil engineer who prepares the approved grading plan to incorporate all recommendations from the soils engineer and engineering geology reports into the grading plan. He also shall be responsible for the professional inspection and approval of the grading within his area of technical specialty. This responsibility shall include, but need not be limited to, inspection and approval as to the establishment of line, grade and drainage of the development area. The civil engineer shall act as the coordinating agent in the event the need arises for liaison between the other professionals, the contractor and the building official. The civil engineer also shall be responsible for the preparation of revised plans and the submission of as-graded grading plans upon completion of the work. The grading contractor shall submit in a form prescribed by the building official a statement of compliance to the as-built plan.
2. Soils engineering and engineering geology reports shall be required as specified. During grading all necessary reports, compaction date and soil engineering and engineering geology recommendations shall be submitted to the civil engineer and the permit authority by the soils engineer and the engineering geologist.
3. The soils engineer’s area of responsibility shall include, but not be limited to, the professional inspection and approval concerning the preparation of ground to receive fills, testing for required compaction, stability of all finish slopes and the design of buttress fills, where required, incorporating data supplied by the engineering geologist.
4. The engineering geologist’s area of responsibility shall include, but need not be limited to, professional inspection and approval of the adequacy of natural ground for receiving fills and the stability of cut slopes with respect to geological matters and the need for subdrains or their ground water drainage devices. He shall report his findings to the soils engineer and the civil engineer for engineering analysis.
5. The permit authority shall inspect the project at the various stages of the work requiring approval to determine that adequate control is being exercised by the professional consultants.
D. Regular Grading Requirements.
1. The permit authority may require inspection and testing by an approved testing agency.
2. The testing agency’s responsibility shall include, but need not be limited to, approval concerning the inspection of cleared areas and benches to receive fill, and the compaction of fills.
3. When the permit authority has cause to believe that geologic factors may be involved, the grading operation will be required to conform to “engineered grading” requirements.
E. Notification of Noncompliance. If, in the course of fulfilling his responsibility under this chapter, the civil engineer, the soils engineer, the engineering geologist or the testing agency finds that the work is not being done in conformance with this chapter or the approved grading plans, the discrepancies shall be reported immediately in writing to the person in charge of the grading work and to the building official. Recommendations for corrective measures, if necessary, shall be submitted.
F. Transfer of Responsibility for Approval. If the civil engineer, the soils engineer, the engineering geologist or the testing agency of record is changed during the course of the work, the work shall be stopped until the replacement has agreed to accept the responsibility within the area of his technical competence for approval upon completion of the work. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 1173 § 6 (part), 2007; Ord. 602 § 16, 1988)
15.16.180 Work completion.
A. Final Reports. Upon completion of the rough grading work and at the final completion of the work the permit authority may require the following reports and drawings and supplements thereof:
1. An as-graded grading plan prepared by the civil engineer including original ground surface elevations, as-graded ground surface elevations, lot drainage patterns and locations and elevations of all surface and subsurface drainage facilities. He shall state that to the best of his knowledge the work was done in accordance with the final approved grading plan.
2. A soils-grading report prepared by the soils engineer, including locations and elevations of field density tests, summaries of field and laboratory tests and other substantiating data and comments on any changes made during grading and their effect on the recommendations made in the soil engineering investigation report. He shall render a finding as to the adequacy of the site for the intended use.
3. A geologic grading report prepared by the engineering geologist, including a final description of the geology of the site and any information disclosed during the grading and the effect of same on recommendations incorporated in the approved grading plan. He shall render a finding as to the adequacy of the site for the intended use as affected by geologic factors.
B. Notification of Completion. The permittee or his agent shall notify the permit authority when the clearing and grading operation is ready for final inspection. Final approval shall not be given until all work and all erosion-control measures have been completed in accordance with the final approved grading plan and the required reports have been submitted. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 602 § 17, 1988)
15.16.190 Enforcement.
A. In the event deficiencies are found, the property owner shall make such corrections as are necessary within fifteen days of the date of written notice by registered mail, return receipt requested, to the owner of record and the occupant of the property.
B. In the event the person or persons violating this chapter shall fail to make corrections within fifteen days of the date of written notice by the city, the city may:
1. Prosecute violations of this chapter as a civil infraction as outlined in Chapter 1.32, General Penalties. The first violation shall constitute a Class III civil infraction, the second offense shall constitute a Class II civil infraction, and the third and each violation thereafter within a one-year period shall be classified as a Class I civil infraction.
2. By council resolution, determine any conditions which constitute or will constitute a violation of any of the provisions of this chapter, or rules or regulations adopted under this chapter, a public nuisance for which the city may seek legal or equitable relief to enjoin any acts or practices or abate any such conditions.
3. Revoke the right to occupancy of the subject property and/or enter on the property as may be required to correct deficiencies as required by the approved grading plan. All costs for corrective measures and enforcement actions shall be borne by the property owner.
C. Notwithstanding any other provision of this chapter, whenever the city engineer finds that a violation of this chapter or rules or regulations adopted under this chapter has created or is creating an unsanitary, dangerous, or other condition which, in his judgment, constitutes an immediate hazard, he may suspend or revoke any permit for which the approval of clearing and grading plan is required on the project or development where the violation exists and suspend or terminate operations under the permit immediately.
D. Any person discharging material which will block, damage or contaminate the drainage system of the city shall be liable for all costs incurred by the city or others in cleaning up or correcting the action and may be charged with a misdemeanor punishable by fines.
E. Penalty or enforcement provisions provided in this chapter shall not be exclusive, and the city may pursue any remedy or relief deemed appropriate in response to a violation of this chapter or the rules and regulations adopted under this chapter. The city council may institute a suit for a mandatory injunction directing a person to remove a structure or make the same comply with its terms. If the city council is successful in its suit, the respondent shall bear the costs of the action.
F. The failure or refusal of the city to enforce any provision of this chapter, and as amended, shall not constitute a waiver or bar to prevent enforcement thereof against any person for any other violation by any other person. (Ord. 1448 § 3 (Exh. C), 2021; Ord. 1390 § 2 (Exh. B) (part), 2016: Ord. 1083 § 19, 2003: Ord. 602 § 18, 1988)