Barstow Municipal Code Ch. 15.12 Grading

(a) Scope. The provisions of this chapter apply to grading, excavation and earthwork construction, including fills and embankments and the control of grading site runoff, including erosion sediments and construction-related pollutants. The purpose of this chapter is to safeguard life, limb, property, and the public welfare by regulating grading on private property.

(b) Flood hazard areas. The provisions of this chapter shall not apply to grading, excavation and earthwork construction, including fills and embankments, in floodways within flood hazard areas established or in flood hazard areas where design flood elevations are specified but floodways have not been designated, unless it has been demonstrated through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that the proposed work will not result in any increase in the level of the base flood.

(c) General hazards. Whenever the building official 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 said property, upon receipt of notice in writing from the building official shall within the period specified therein repair or eliminate such excavation or embankment to eliminate the hazard and to be in conformance with the requirements of this Code.

(d) Safety precautions. If at any stage of the work the building official determines by inspection that further grading as authorized is likely to endanger any public or private property or result in the deposition of debris on any public way or interfere with any existing drainage course, the building official may order the work stopped by notice in writing served on any persons engaged in doing or causing such work to be done, and any such person shall immediately stop such work. The building official may authorize the work to proceed if the building official finds adequate safety precautions can be taken or corrective measures incorporated in the work to avoid the likelihood of such danger, deposition or interference. If the grading work as done has created or resulted in a hazardous condition, the building official shall give written notice requiring correction thereof as specified in section 15.12.050.

(e) Protection of utilities. The owner of any property on which grading has been performed and that requires a grading permit under section 15.12.030 shall be responsible for the prevention of damage to any public utilities or services.

(f) Protection of adjacent property. The owner of any property on which grading has been performed and that requires a grading permit under section 15.12.030 is responsible for the prevention of damage to adjacent property and no person shall excavate on land sufficiently close to the property line to endanger any adjoining public street, sidewalk, alley, or other public or private property without supporting and protecting such property from settling, cracking or other damage that might result. Special precautions approved by the building official shall be made to prevent imported or exported materials from being deposited on the adjacent public way and/or drainage courses.

(g) Stormwater control measures. The owner of any property on which grading has been performed and that requires a grading permit under section 15.12.030 shall put into effect and maintain all precautionary measures necessary to protect adjacent watercourses and public or private property from damage by erosion, flooding, and deposition of mud, debris, and construction-related pollutants originating from the site during grading and related construction activities.

(h) Maintenance of private devices. The owner of any property on which grading has been performed pursuant to a permit issued under the provisions of this Code, or any other person or agent in control of such property, shall maintain in good condition and repair all drainage structures and other protective devices when they are shown on the grading plans filed with the application for grading permit and approved as a condition precedent to the issuance of such permit.

(i) Conditions of approval. In granting any permit under this Code, the building official may include such conditions as may be reasonably necessary to prevent creation of a nuisance or hazard to public or private property. Such conditions may include, but shall not be limited to:

(1) Improvement of any existing grading to comply with the standards of this Code;

(2) Requirements for fencing of excavations or fills which would otherwise be hazardous.

(Code 1969, § 15.12.010; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

For the purposes of this chapter, the terms, phrases, and words listed in this section and their derivatives have the indicated meanings, unless the context or subject matter otherwise requires:

Bench means the relatively level step excavated into earth material on which fill is to be placed.

Borrow means earth material acquired from an off-site location for use in grading on a site.

Civil engineer means a professional engineer registered in the state to practice in the field of civil works.

Civil engineering means the application of the knowledge of the forces of nature, principles of mechanics, and the properties of materials to the evaluation, design, and construction of civil works.

Compaction means the densification of a fill by mechanical means.

Cut. See Excavation.

Design engineer means the civil engineer responsible for the preparation of the grading plans for the site grading work.

Desilting basins means physical structures constructed for the removal of sediments from surface water runoff.

Down drain means a device for collecting water from a swale or ditch located on or above a slope, and safely delivering it to an approved drainage facility.

Earth material means any rock, natural soil, or fill or any combination thereof.

Engineering geologist means a geologist experienced and knowledgeable in engineering geology holding a valid certificate of registration as a geologist in the specialty of engineering geology issued by the state under the applicable provisions of the Geologist and Geophysicist Act of the Business and Professions Code.

Engineering geology means the application of geologic knowledge and principles in the investigation and evaluation of naturally occurring rock and soil for use in the design of civil works.

Erosion means the wearing away of the ground surface as a result of the movement of wind, water, or ice.

Excavation means the removal of earth material by artificial means, also referred to as a cut.

Field engineer means the civil engineer responsible for performing the functions as set forth in section J105.2 of the CBC appendix J.

Fill means the deposition of earth materials by artificial means.

Geotechnical engineer. See Soils engineer.

Geotechnical hazard means an adverse condition due to landslide, settlement, and/or slippage. These hazards include but are not limited to loose debris, slope wash, and mud flows from natural or graded slopes.

Grade means the vertical location of the ground surface.

Grade, existing, means the grade prior to grading.

Grade, final. See section 15.12.050(g)(4).

Grade, finished, means the grade of the site at the conclusion of all grading efforts.

Grade, initial. See section 15.12.050(g)(2).

Grade, rough. See section 15.12.050(g)(3).

Grading means an excavation or fill or combination thereof.

Key means a compacted fill placed in a trench excavated in earth material generally constructed at the toe of the slope.

Landscape architect means a person who holds a certificate to practice landscape architecture in the state under the applicable landscape architecture provisions of division 3, chapter 3.5 of the Business and Professions Code.

Line means and refers to the horizontal location of the ground surface.

Permittee. See section 15.120.050(f).

Private sewage disposal system means a septic tank with effluent discharging into a subsurface disposal field, into one or more seepage pits or into a combination of subsurface disposal field and seepage pit or such other facilities as may be permitted.

Professional inspection means the inspection required by this Code to be performed by the project consultants. Such inspections shall be sufficient to form an opinion relating to the conduct of the work.

Project consultants means the professional consultants required by this Code which may consist of the design engineer, field engineer, soils engineer, engineering geologist, and landscape architect as applicable to this chapter.

Site means a lot or parcel of land or contiguous combination thereof, under the same ownership, where grading is performed or permitted.

Slope means an inclined ground surface, the inclination of which is expressed as a ratio of horizontal distance to vertical distance.

Soil means naturally occurring superficial deposits overlying parent bedrock.

Soil testing agency means an agency regularly engaged in the testing of soils and rock under the direction of a civil engineer experienced in soil testing.

Soils engineer (geotechnical engineer) means an engineer experienced and knowledgeable in the practice of soils engineering (geotechnical) engineering.

Soils engineering (geotechnical engineering) means the application of the principles of soils mechanics in the investigation, evaluation, and design of civil works involving the use of earth materials and the inspection or testing of construction thereof.

Storm drain system means a conveyance or system of conveyances, including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, and manmade channels, designed or used for collecting and conveying stormwater.

Stormwater pollution prevention plan (SWPPP) means a site drawing with details, notes and related documents that identify the measures proposed by the permittee to:

(1) Control erosion and prevent sediment and construction-related pollutants from being carried off-site by stormwater; and

(2) To prevent non-stormwater discharges from entering the storm drain system.

Surface drainage means flows over the ground surface.

Terrace means a relatively level step constructed in the face of a graded slope for drainage and maintenance purposes.

(Code 1969, § 15.12.020; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) Permits required. Except as exempted in subsection (b) of this section, no grading shall be performed without first having obtained a permit from the building official. A grading permit does not include the construction of retaining walls or other structures. A separate permit shall be obtained for each site and may cover both excavations and fills. Any engineered grading as described in section 15.12.040 shall be performed by a contractor licensed by the state to perform the work described hereon. Regular grading less than 5,000 cubic yards may require a licensed contractor if the building official determines that special conditions or hazards exist.

(b) Exemptions. A grading permit shall not be required for the following:

(1) When approved by the building official, grading in an isolated, self-contained area, provided there is no danger to the public, and that such grading will not adversely affect adjoining properties;

(2) Excavation for construction of a structure permitted under this Code;

(3) Cemetery graves;

(4) Refuse disposal sites controlled by other regulations;

(5) Excavations for wells, or trenches for utilities;

(6) Mining, quarrying, excavating, processing or stockpiling rock, sand, gravel, aggregate, or clay controlled by other regulations, provided such operations do not affect the lateral support of, or significantly increase stresses in, soil on adjoining properties;

(7) Exploratory excavations performed under the direction of a soils engineer or engineering geologist. This shall not exempt grading of access roads or pads created for exploratory excavations. Exploratory excavations must be restored to existing conditions, unless approved by the building official;

(8) An excavation that does not exceed 50 cubic yards (38.3 m3) and complies with one of the following conditions:

a. Is less than two feet (0.6 m) in depth;

b. Does not create a cut slope greater than five feet (1.5 m) measured vertically upward from the cut surface to the surface of the natural grade and is not steeper than two units horizontal to one unit vertical (50 percent slope);

(9) A fill not intended to support a structure, that does not obstruct a drainage course and complies with one of the following conditions:

a. Is less than one foot (0.3 m) in depth and is placed on natural terrain with a slope flatter than five units horizontal to one unit vertical (20 percent slope);

b. Is less than three feet (0.9 m) in depth at its deepest point measured vertically upward from natural grade to the surface of the fill, does not exceed 50 cubic yards, and creates a fill slope no greater than two units horizontal to one unit vertical (50 percent slope);

c. Is less than five feet (1.5 m) in depth at its deepest point measured vertically upward from natural grade to the surface of the fill, does not exceed 20 cubic yards, and creates a fill slope no steeper than two units horizontal and one unit vertical (50 percent slope).

Exemption from the permit requirements of this section shall not be deemed to grant authorization for any work to be done in any manner in violation of the provisions of this Code or any other laws or ordinances of this jurisdiction.

(c) Unpermitted grading. A person shall not own, use, occupy or maintain any site containing unpermitted grading. For the purposes of this Code, unpermitted grading shall be defined as any grading that was performed, at any point in time, without the required permits having first been obtained from the building official, pursuant to subsection (a) of this section.

(d) Availability of permit at site. No person shall perform any grading that requires a permit under this chapter unless a copy of the grading permit and approved grading plans is in the possession of a responsible person and available at the site for the building official.

(Code 1969, § 15.12.030; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) Submittal requirements. In addition to the provisions of California Building Code (CBC) appendix J, section 104, the applicant shall state the estimated quantities of excavation and fill.

(b) Site plan requirements. In addition to the provisions of CBC appendix J section 104, a grading plan shall show the existing grade and finished grade in contour intervals of sufficient clarity to indicate the nature and extent of the work and show in detail that it complies with the requirements of this Code. The plans shall show the existing grade on adjoining properties in sufficient detail to identify how grade changes will conform to the requirements of this Code.

(c) Grading designation. Grading in excess of 5,000 cubic yards (3,825 m 3 ) or for the support of a structure shall be performed in accordance with the approved grading plan prepared by a civil engineer, and shall be designated as "engineered grading." Grading involving less than 5,000 cubic yards (3,825 m 3 ) and not for the support of a structure shall be designated "regular grading" unless the permittee chooses to have the grading performed as engineered grading, or the building official determines that special conditions or unusual hazards exist, in which case grading shall conform to the requirements for engineered grading.

(d) Regular grading requirements. In addition to the provisions of CBC chapter 1, division II, section 107, and subsection (b) of this section, an application for a regular grading permit shall be accompanied by two sets of plans in sufficient clarity to indicate the nature and extent of the work. The plans shall give the location of the work, the name of the owner, and the name of the person who prepared the plan. The plan shall include the following information:

(1) General vicinity of the proposed site;

(2) Limits and depths of cut and fill;

(3) Location of any buildings or structures where work is to be performed and the location of any buildings or structures within 15 feet (4.57 m) of the proposed grading;

(4) Contours, flow areas, elevations, or slopes which define existing and proposed drainage patterns.

(e) Engineered grading requirements.

(1) In addition to the provisions of CBC chapter 1, division II, section 107, and subsection (b) of this section, an application for an engineered grading permit shall be accompanied by four sets of plans and specifications, and supporting data consisting of a soils engineering report and engineering geology report. The plans and specifications shall be prepared and signed by an individual licensed by the state to prepare such plans or specifications when required by the building official.

(2) Specifications shall contain information covering construction and material requirements. Plans shall be drawn to scale upon substantial paper or cloth and shall be of sufficient clarity to indicate the nature and extent of the work proposed and show in detail that it will conform to the provisions of this Code and all relevant laws, ordinances, rules, and regulations. The first sheet of each set of plans shall give location of the work, the name and address of the owner, and the person by whom they were prepared.

(3) The plans shall include but shall not be limited to, the following information:

a. General vicinity of the proposed site;

b. Property limits and accurate contours of existing ground and details of terrain and area drainage;

c. Limiting dimensions, elevations, or finish contours to be achieved by the grading, proposed drainage channels, and related construction;

d. 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. A map showing the drainage area and the estimated runoff of the area served by any drains shall also be provided;

e. Location of any existing or proposed buildings or structures on the property where the work is to be performed and the location of any buildings or structures on land of adjacent owners who are within 15 feet (4.57 m) of the property that may be affected by the proposed grading operations;

f. Recommendations in the soils engineering report and the engineering geology report shall be incorporated into the grading plans or specifications. When approved by the building official, specific recommendations contained in the soils engineering report and the engineering geology report that are applicable to grading may be included by reference;

g. The dates of the soils engineering and engineering geology reports together with the names, addresses, and phone numbers of the firms or individuals who prepared the reports;

h. A statement of the earthwork quantities of material to be excavated and/or filled. Earthwork quantities shall include quantities for geotechnical and geological remediation. In addition, a statement of material to be imported or exported from the site;

i. A statement of the estimated starting and completion dates for work covered by the permit;

j. A statement signed by the owner acknowledging that a field engineer, soils engineer and engineering geologist, when appropriate, will be employed to perform the services required by this Code, whenever approval of plans and issuance of permit are to be based on the condition that such professional persons be so employed. These acknowledgements shall be on a form furnished by the building official;

k. A drainage plan for that portion of a lot or parcel to be utilized as a building site (building pad), including elevations of floors with respect to finish site grade and locations of proposed stoops, slabs and fences that may affect drainage;

l. Location and type of any proposed private sewage disposal system;

m. Location of existing and proposed utilities, drainage facilities, and recorded public and private easements;

n. Location of all recorded natural drainage courses and drainage easements.

(f) Soils engineering report. The soils engineering report required by subsection (e) of this section shall include data regarding the nature, distribution and strength of existing soils, conclusions and recommendations for grading procedures and design criteria for corrective measures, including buttress fills, when necessary, and opinion on adequacy for the intended use of sites to be developed by the proposed grading as affected by soils engineering factors, including the stability of slopes. Supplemental reports and data may be required as the building official may deem necessary. Recommendations included in the reports and approved by the building official shall be incorporated in the grading plan or specifications.

(g) Engineering geology report. The engineering geology report required by subsection (e) of this section 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 opinion on the adequacy for the intended use of sites to be developed by the proposed grading, as affected by geologic factors. The engineering geology report shall include a geologic map and cross sections utilizing the most recent grading plan as a base. Supplemental reports and data may be required as the building official may deem necessary. Recommendations included in the reports and approved by the building official shall be incorporated in the grading plan or specifications.

(Code 1969, § 15.12.040; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) General. Grading inspections shall be governed by CBC chapter 1, division II, section 110. Grading operations for which a permit is required shall be subject to inspection by the building official. Professional inspection of grading operations shall be provided by the field engineer, soils engineer and the engineering geologist retained to provide such services in accordance with this section for engineered grading and as required by the building official for regular grading.

(b) Special and supplemental inspections.

(1) The special inspection requirements of CBC section 1704.7 shall apply to work performed under a grading permit where required by the building official. In addition to the called inspections specified in subsection (g) of this section, the building official may make such other inspections as may be deemed necessary to determine that the work is being performed in conformance with the requirements of this Code. Investigations and reports by an approved soil testing agency, soils engineer and/or engineering geologist, and field engineer may be required. Inspection reports shall be provided when requested by the building official.

(2) Continuous inspection of drainage devices by the field engineer in accordance with this section may be required when the building official determines the drainage devices are necessary for the protection of the structures in accordance with section 15.12.090.

(c) Field engineer. The field engineer shall provide professional inspection within such engineer's area of technical specialty, oversee and coordinate all field surveys, set grade stakes, and provide site inspections during grading operations to ensure the site is graded in accordance with the approved grading plan and the appropriate requirements of this Code. During site grading, and at the completion of both rough grading and final grading, the field engineer shall submit statements and reports required by sections 15.12.110 and 15.12.120. If the revised grading plans are required during the course of work, they shall be prepared by a civil engineer and approved by the building official.

(d) Soils engineer. The soils engineer shall provide inspection within such engineer's area of technical specialty, which shall include observation during grading and testing for required compaction. The soils engineer shall provide sufficient observation during the preparation of the natural ground and placement and compaction of the fill to verify that such work is being performed in accordance with the conditions of the approved plan and the appropriate requirements of this chapter. Revised recommendations relating to conditions differing from the approved soils engineering and engineering geology reports shall be submitted to the permittee, the building official and the field engineer.

(e) Engineering geologist. The engineering geologist shall provide professional inspection within such engineer's area of technical specialty, which shall include professional inspection of the excavation to determine if conditions encountered are in conformance with the approved report. Revised recommendations relating to conditions differing from the approved engineering geology report shall be submitted to the soils engineer.

(f) Permittee. The permittee shall be responsible for the work to be performed in accordance with the approved plans and specifications and in conformance with the provisions of this Code and the permittee shall engage project consultants, if required, to provide professional inspections on a timely basis. The permittee shall act as a coordinator between the project consultants, the contractor, and the building official. In the event of changed conditions, the permittee shall be responsible for informing the building official of such change and shall provide revised plans for approval.

(g) Building official. The building official shall inspect the project site at the following various stages of work requiring approval to determine that adequate control is being exercised by the project consultants:

(1) Pre-grade. Before any construction or grading activities occur at the site, the permittee shall schedule a pre-grade inspection with the building official. The permittee is responsible for coordinating that all project consultants are present at the pre-grade inspection;

(2) Initial. When the site has been cleared of vegetation and unapproved fill and it has been scarified, benched or otherwise prepared for fill. No fill shall have been placed prior to this inspection;

(3) Rough. When approximate final elevations have been established; drainage terraces, swales, and other drainage devices necessary for the protection of the building sites from flooding are installed; berms are installed at the top of the slopes; and the statements required by subsection (l) of this section have been received;

(4) Final. When grading has been completed; all drainage devices necessary to drain the building pad are installed; slope planting is established, irrigation systems are installed; and the as-graded plans and required statements and reports have been submitted.

(h) Notification of noncompliance. If, in the course of fulfilling their respective duties under this chapter, the field engineer, the soils engineer or the engineering geologist finds that the work is not being done in conformance with this chapter or the approved grading plans, the discrepancies and corrective measures which should be taken shall be reported immediately in writing to the permittee and to the building official.

(i) Transfer of responsibility. If the field engineer, the soils engineer, or the engineering geologist of record is changed during the grading, the work shall be stopped until the replacement has agreed in writing to accept their responsibility within the area of technical competence for approval upon completion of the work. It shall be the duty of the permittee to notify the building official in writing of such change prior to the recommencement of such grading.

(j) Noninspected grading. No person shall own, use, occupy, or maintain any noninspected grading. For the purpose of this Code, noninspected grading shall be defined as any grading for which a grading permit was first obtained, pursuant to section 15.12.030, but which has progressed beyond any point requiring inspection and approval by the building official without such inspection and approval having been obtained.

(k) Routine field inspections and reports. Unless waived by the building official, routine inspection reports shall be provided by the field engineer for all engineered grading projects. The field engineer shall file these reports, with the building official as follows:

(1) Bi-weekly during all times when grading of 400 cubic yards or more per week is active on the site;

(2) Monthly, at all other times; and

(3) At any time when requested in writing by the building official.

Such reports shall certify to the building official that the field engineer has inspected the grading site and related activities and has found them in compliance with the approved grading plans, the building code, grading permit conditions, and other applicable ordinances and requirements.

(l) Completion of work. Upon completion of the rough grading work and at the final completion of the work, the following reports and drawings and supplements thereto are required for engineered grading or when professional inspection is required by the building official:

(1) An as-built grading plan prepared by the field engineer retained to provide such services in accordance with subsection (c) of this section showing all plan revisions as approved by the building official. This shall include original ground surface elevations, as-built ground surface elevations, lot drainage patterns, and the locations and elevations of surface drainage facilities and the outlets of subsurface drains. As-built locations, elevations and details of subsurface drains shall be shown as reported by the soils engineer. The field engineer shall state in a report, to the building official, that to the best of their knowledge, the work within their area of responsibility was done in accordance with the final approved grading plan;

(2) A report prepared by the soils engineer retained to provide such services in accordance with subsection (d) of this section including locations and elevations of field density tests, summaries of field and laboratory tests, other substantiating data, and comments on any changes made during grading and their effect on the recommendations made in the approved soils engineering report. Soils engineers shall submit a statement that, to the best of their knowledge, the work within their area of responsibilities is in accordance with the approved soils engineering report and applicable provisions of this chapter. The reports shall contain a finding regarding the safety of the completed grading and any proposed structures against hazard from landslide, settlement, or slippage;

(3) A report prepared by the engineering geologist retained to provide such services in accordance with subsection (e) of this section including a final description of the geology of the site and any new information disclosed during the grading and the effect of same on recommendations incorporated in the approved grading plan. Engineering geologists shall submit a statement that, to the best of their knowledge, the work within their area of responsibility is in accordance with the approved engineering geologist report and applicable provisions for this chapter. The report shall contain a finding regarding the safety of the completed grading and any proposed structures against hazard from landslide, settlement, or slippage. The report must contain a final as-built geologic map and cross sections depicting all the information collected prior to and during grading;

(4) The grading contractor shall submit in a form prescribed by the building official a statement of conformance to said as-built plan and the specifications.

(m) Notification of completion. The permittee shall notify the building official when the grading operation is ready for final inspection. Final approval shall not be given until all work, including installation of all drainage facilities and their protective devices, and all erosion control measures have been completed in accordance with the final approved grading plan, and the required reports have been submitted and approved.

(n) Change of ownership. If a grading permit has been issued on a property and the building official has not approved the final grading when a property changes ownership, a new grading application and permit will be required from the new property owner.

(Code 1969, § 15.12.050; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) General. Unless otherwise recommended in the approved soils engineering or engineering geology report, cuts shall conform to the provisions of this section. In the absence of an approved soils engineering or engineering geology report, these provisions may be waived, as approved by the building official, for minor cuts not intended to support structures or subject to a surcharge.

(b) Maximum cut slope. The slope of cut surfaces shall be no steeper than is safe for the intended use and shall be no steeper than two units horizontal to one unit vertical (50 percent slope) unless the permittee 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 building official may require the excavation to be made with a cut face flatter in slope than two units horizontal to one unit vertical if the building official finds it necessary for stability and safety.

(c) Slope surface protection. All slopes must be stabilized against surface erosion. Stabilization may be accomplished through the application of erosion control blankets, soil stabilizers or other means as approved by the building official.

(Code 1969, § 15.12.060; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) General. Unless otherwise recommended in the approved soils engineering report, fills shall conform to the provisions of this section. In the absence of an approved soils engineering report, and if approved by the building official, these provisions may be waived for minor fills not intended to support structures.

FIGURE 15.12.070. BENCHING DETAILS

[Figure]

(b) Preparation of ground. Fill slopes shall not be constructed on natural slopes steeper than two units horizontal to one unit vertical (50 percent slope). The ground structure shall be prepared to receive fill by removing vegetation, noncomplying fill, topsoil and other unsuitable materials scarifying to provide a bind with the new fill. Where slopes are steeper than five units horizontal to one unit vertical (20 percent slope) and the height is greater than five feet (1.53 m), the ground surface shall be prepared to receive fill by benching into sound bedrock or other competent material as determined by the soils engineer. The ground preparation shall be in accordance with figure 15.12.070 or as determined by the soils engineer. The key under the toe of the fill on a slope steeper than five units horizontal to one unit vertical (20 percent slope) shall be at least ten feet (3.05 m) 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 key shall be at least ten feet (3.05 m) wide. The cut shall be made before placing the fill and the soils engineer or engineering geologist or both shall accept the cut as suitable for the foundation and placement of fill material.

(c) Subdrains. Except where recommended by the soils engineer or engineering geologist as not being necessary, subdrains shall be provided under all fills placed in natural drainage courses and in other locations where seepage is evident. Such subdrainage systems shall be of a material and design approved by the soils engineer and acceptable to the building official. The soils engineer shall provide continuous inspection during the process of subdrain installation to conform to the approved plans and the engineering geologist's and soil engineer's recommendation. Testing of materials shall be done by a soil testing agency based on the soil engineer's or engineering geologist's recommendation. The location of the subdrains shall be shown on a plan by the soils engineer. Excavations for the subdrains shall be inspected by the engineering geologist when such subdrains are included in the recommendations of the engineering geologist.

(d) Fill material.

(1) Detrimental amounts of organic material shall not be permitted in fills. Unless approved by the building official, no rock or similar irreducible material with a maximum dimension of greater than 12 inches (0.305 m) shall be buried or placed in fills.

(2) Exception: The building official may permit placement of larger rock when the soils engineer properly devises a method of placement, and 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 12 inches (0.305 m) in maximum dimension shall be ten feet (3.05 m) or more below grade, measured vertically;

c. Rocks shall be placed so as to assure filling of all voids with well-graded soil;

d. The reports submitted by the soils engineer shall acknowledge the placement of the oversized material and whether the work was performed in accordance with the engineer's recommendations and the approved plans;

e. The location of the oversized rock dispersal areas shall be shown on the as-built plan.

(e) Compaction.

(1) All fills shall be compacted to a minimum of 90 percent of maximum density. Fills shall be compacted throughout their full extent to a minimum relative compaction of 90 percent of maximum dry density within 40 feet (12.19 m) below finished grade and 93 percent of maximum dry density deeper than 40 feet (12.19 m) below finished grade, unless a lower relative compaction (not less than 90 percent of maximum dry density) is justified by the soils engineer. The relative compaction shall be determined by A.S.T.M. soil compaction test D1557 where applicable. Where not applicable, a test acceptable to the building official, shall be used unless the owner furnishes a soils engineering report conforming with the requirements of section 15.12.040(e), stating that the site has been investigated and giving an opinion that a fill at a steeper slope will be stable and not create a hazard to public or private property. Substantiating calculations and supporting data may be required where the building official determines that such information is necessary to verify the stability and safety of the proposed slope. The building official may require the fill slope be constructed with a face flatter in slope than two units horizontal to one unit vertical (50 percent slope) if the building official finds it necessary for stability and safety.

(2) Field density shall be determined by a method acceptable to the building official. However, not less than ten percent of the required density tests, uniformly distributed, shall be obtained by the sand cone method.

(3) Fill slopes steeper than two units horizontal to one unit vertical (50 percent slope) shall be constructed by the placement of soil a sufficient distance beyond the proposed finish slope to allow compaction equipment to operate at the outer surface limits of the final slope surface. The excess fill is to be removed prior to completion or rough grading. Other construction procedures may be utilized when it is first shown to the satisfaction of the building official that the angle of slope, construction method and other factors will comply with the intent of this section.

(f) Maximum fill 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 units horizontal in one unit vertical (50 percent slope) unless calculations are provided by a soils engineer which indicate a steeper slope will be stable and approved by the building official.

(g) Slopes to receive fill. Where fill is to be placed above the top of an existing slope steeper than three units horizontal to one unit vertical (33 percent slope), the toe of the fill shall be set back from the top edge of the slope a minimum distance of six feet (1.83 m) measured horizontally or such other distance as may be specifically recommended by a soils engineer or engineering geologist and approved by the building official.

(h) Inspection of fill. For engineered grading, the soils engineer shall provide sufficient inspections during the preparation of the natural ground and the placement and compaction of the fill ensuring that the work is being performed in accordance with the conditions of plan approval and the appropriate requirements of this chapter. In addition to the above, the soils engineer shall be present during the entire fill placement and compaction of fills that will exceed a vertical height or depth of 30 feet (9.14 m) or result in a slope surface steeper than two units horizontal to one unit vertical (50 percent slope).

(i) Testing of fills. Sufficient tests of the fill soils shall be made to determine the density and to verify compliance of the soil properties with the design requirements. This includes soil types and shear strengths in accordance with referenced standards in section 15.12.120.

(Code 1969, § 15.12.070; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) General. Cut and fill slopes shall be set back from the property lines in accordance with this section. Setback dimensions shall be horizontal distances measured perpendicular to the property line and shall be as shown in figure 15.12.080 unless substantiating data is submitted justifying reduced setbacks is recommended by soils engineering and engineering geology reports approved by the building official.

(b) Top of slope. The setback at the top of a cut slope shall not be less than that shown in figure 15.12.080, or than is required to accommodate any required interceptor drains, whichever is greater. For manufactured slopes the grading design must be such that the property line between adjacent lots will be at the apex of the berm at the top of the slope. Property lines between adjacent lots cannot be located on a graded slope equal to five units horizontal to one unit vertical (20 percent slope).

FIGURE 15.12.080 SETBACK DIMENSIONS

[Figure]

(c) Toe of fill slope. The setback from the toe of a fill slope shall not be less than that shown by figure 15.12.080. Where required to protect adjacent properties at the toe of a slope from adverse effects of the grading, additional protection, approved by the building official, shall be included. Such protection may include but shall not be limited to:

(1) Setbacks greater than those required by figure 15.12.080;

(2) Provisions for retaining walls or similar construction;

(3) Erosion protection of the fill slopes;

(4) Provision for the control of surface waters.

(d) Alternate setbacks. The building official may approve alternate setbacks. The building official may require an investigation and recommendation by a qualified engineer or engineering geologist to demonstrate that the intent of this section has been satisfied.

(Code 1969, § 15.12.080; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) General. Unless otherwise recommended by a registered design professional, and approved by the building official, drainage facilities and terracing shall be provided in accordance with the requirements of subsection (b) of this section for all cut and fill slope where the ground slope is steeper than three units horizontal to one unit vertical (33 percent slope). For slopes flatter than three units horizontal to one unit vertical (33 percent slope) and steeper than five units horizontal to one unit vertical (20 percent slope), a paved swale or ditch shall be provided at 30-foot (9.14 m) vertical intervals to control surface drainage and debris. Swales shall be sized based on contributory area and have adequate capacity to convey intercepted waters to the point of disposal as defined in subsection (e) of this section. Swales must be paved with reinforced concrete not less than three inches (0.0762 m) in thickness, reinforced with six-inch (0.153 m) by six-inch (0.153 m) "No. 10 by No. 10" welded wire fabric or equivalent reinforcing centered in the concrete slab or an approved equal. Swales must have a minimum gradient of not less than five percent. There shall be no reduction in grade along the direction of flow unless the velocity of flow is such that slope debris will remain in suspension on the reduced grade.

(b) Drainage terraces. Drainage terraces at least eight feet (2.44 m) in width shall be established at not more than 30-foot (9.14 m) vertical intervals on all cut and fill slopes to control surface drainage and debris. When only one terrace is required, it shall be mid-height. For cut or fill slopes greater than 100 feet (30.5 m) and up to 120 feet (36.576 m) in vertical height, one terrace at approximately mid-height shall be 20 feet (6 m) in width. Terrace widths and spacing for cut and fill slopes greater than 120 feet (36.6 m) in height shall be designed by the civil engineer and approved by the building official. Suitable access shall be provided to permit proper cleaning and maintenance. Drainage swales on terraces shall have a longitudinal grade of not less than five percent and no more than 12 percent and a minimum depth of one foot (0.305 m) at the flow line. There shall be no reduction in grade along the direction of flow unless the velocity of flow is such that slope debris will remain in suspension on the reduced grade. Such terraces must be paved with reinforced concrete not less than three inches (0.076 m) in thickness, reinforced with six-inch (0.2 m) by six-inch (0.152 m) "No. 10 by No. 10" welded wire fabric or equivalent reinforcing centered in the concrete slab or an approved equal paving. They shall have a minimum depth at the deepest point of one foot (0.3 m) and a minimum paved width of five feet (1.524 m). Drainage terraces exceeding eight feet (2.438 m) in width need only be so paved for a width of eight feet (2.438 m), provided such pavement provides a paved swale at least one foot (0.305 m) in depth. Down drains or drainage outlets shall be provided at approximately 300-foot (91.44 m) intervals along the drainage terrace or at equivalent locations. Down drains and drainage outlets shall be of approved materials and of adequate capacity to convey the intercepted waters to the point of disposal as defined in subsection (e) of this section.

(c) Interceptor drains and overflow protection.

(1) Berms, interceptor drains, swales, or other devices shall be provided at the top of cut or fill slopes to prevent surface waters from overflowing onto and damaging the face of a slope. Berms used for slope protection shall not be less than 12 inches (3.0 m) above the level of the pad and shall slope back at least four feet (1.22 m) from the top of the slope.

(2) Interceptor drains shall be installed along the top of manufactured slopes greater than five feet in height receiving drainage from a slope with a tributary width greater than 30 feet (9.1 m) measured horizontally. They shall have a minimum depth of one foot (0.305 m) and a minimum width of three feet (0.914 m). The slope shall be approved by the building official, but shall not be less than 50 horizontal to one vertical (two percent). The drain shall be paved with concrete not less than three inches (0.076 m) in thickness, or by other materials suitable to the application and reinforced as required for drainage terraces. Discharge from the drain shall be accomplished in a manner to prevent erosion and shall be approved by the building official.

(d) Drainage across property lines. Drainage across property lines shall not exceed that which existed prior to grading. Excess or concentrated drainage shall be contained on site or directed to an approved drainage facility. Erosion of the ground in the area of discharge shall be prevented by installation of nonerosive down drains or other devices.

(e) Disposal.

(1) All drainage facilities shall be designed to carry waters to the nearest practicable street, storm drain, or natural watercourse drainage way approved by the building official or other appropriate governmental agency jurisdiction, provided it is a safe place to deposit such waters. Erosion of ground in the area of discharge shall be prevented by installation of nonerosive down drains or other devices. Desilting basins, filter barriers or other methods, as approved by the building official, shall be utilized to remove sediments from surface waters before such waters are allowed to enter streets, storm drains, or natural watercourses. If the drainage device discharges onto natural ground, riprap or a similar energy dissipater may be required.

(2) Building pads shall have a minimum drainage gradient of two percent toward approved drainage facilities, a public street or drainage structure approved to receive stormwaters unless waived by the building official. A lesser slope may be approved by the building official for sites graded in relatively flat terrain, or where special drainage provisions are made, when the building official finds such modification will not result in unfavorable drainage conditions.

(Code 1969, § 15.12.090; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) General.

(1) The faces of cut and fill slopes shall be prepared and maintained to control against erosion. This control shall consist of effective planting, erosion control blankets, soil stabilizers or other means as approved by the building official.

(2) Exception: Erosion control measures need not be provided on cut slopes not subject to erosion due to the erosion-resistant character of materials as approved by the project consultants to the satisfaction of the building official.

(3) Erosion control for the slopes shall be installed as soon as practicable and prior to calling for final inspection.

(b) Other devices. Where necessary, check dams, cribbing, riprap or other devices or methods shall be employed to control erosion and provide safety.

(c) Planting.

(1) The surface of all cut slopes more than five feet (1.52 m) in height and fill slopes more than three feet (0.9144 m) in height shall be protected against damage by erosion. Slopes exceeding 15 feet (4.57 m) in vertical height shall be planted with shrubs, spaced at not to exceed ten feet (3.048 m) on centers; or trees, spaced at not to exceed 20 feet (6.096 m) on centers; or a combination of shrubs and trees at equivalent spacings. The plants selected and planting methods used shall be suitable for the soil and climatic conditions of the site. Plant material shall be selected which will produce a coverage of permanent planting to effectively control erosion. Consideration shall be given to deep-rooted plant material needing limited watering, maintenance, high root to shoot ratio, wind susceptibility and fire retardant characteristics. All plant materials must be approved by the building official.

(2) Planting may be modified for the site if specific recommendations are provided by both the soils engineer and a landscape architect. Specific recommendations must consider soils and climatic conditions, irrigation requirements, planting methods, fire retardant characteristics, water efficiency, maintenance needs, and other regulatory requirements. Recommendations must include a finding that the alternative planting will provide a permanent and effective method of erosion control. This modified planting shall be approved by the building official.

(d) Irrigation. Slopes required to be planted by subsection (c) of this section shall be provided with an approved system of irrigation that is designed to cover all portions of the slope. Irrigation system plans shall be submitted and approved prior to installation. A functional test of the system may be required. Specific recommendations must consider soils and climatic conditions, plant types, planting methods, fire retardant characteristics, water efficiency, maintenance needs, and other regulatory requirements. Modifications for irrigation systems shall be approved by the building official.

(e) Plans and specifications. Planting and irrigation plans shall be submitted for slopes required to be planted and irrigated by subsections (c) and (d) of this section. Except as waived by the building official for minor grading, the plans for slopes 20 feet (6.096 m) or more in vertical height shall be prepared and signed by a civil engineer or landscape architect. If requested by the building official, planting and irrigation details shall be included on the grading plan.

(f) Release of security. The planting and irrigation systems required by this section shall be installed as soon as practical after rough grading. Prior to final approval of grading and before the release of the grading security, the planting shall be well established and growing on the slopes.

(Code 1969, § 15.12.100; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) General.

(1) All grading plans and permits shall comply with the provisions of this section for NPDES compliance.

(2) All best management practices shall be installed before grading begins. All best management practices shall be updated as necessary to prevent erosion and control construction-related pollutants from discharging from the site. All best management practices shall be maintained in good working order to the satisfaction of the building official unless final grading approval has been granted by the building official and all permanent drainage and erosion control systems, if required, are in place.

(b) Stormwater pollution prevention plan (SWPPP). When requested by the building official, no grading permit shall be issued unless the plans for such work include a stormwater pollution prevention plan with details of best management practices, including desilting basins or other temporary drainage or control measures, or both, as may be necessary to control construction-related pollutants which originate from the site as a result of construction-related activities.

(Code 1969, § 15.12.110; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)

(a) These regulations establish minimum standards and are not intended to prevent the use of alternate materials, methods or means of conforming to such standards, provided such alternate has been approved.

(1) The building official shall approve such an alternate, provided he or she finds that the alternate is, for the purpose intended, at least the equivalent of that prescribed in this Code in quality, strength, effectiveness, durability and safety.

(2) The building official shall require that sufficient evidence or proof be submitted to substantiate any claims regarding the alternate.

(b) The standards listed below are recognized standards:

1.1 ASTM D 1557—Laboratory Characteristics Compaction of Soil Using Modified Effort.

1.2 ASTM D 1556—Density and Unit Weight of Soils in Place by the Sand Cone Method.

1.3 ASTM D 2167—Density and Unit Weight of Soils in Place by the Rubber—Balloon Method.

1.4 ASTM D 2937—Density of Soils in Place by the Drive-Cylinder Method.

1.5 ASTM D 2922—Density of Soil and Soil Aggregate in Place by Nuclear Methods.

1.6 ASTM D 3017—Water Content of Soil and Rock in Place by Nuclear Methods.

(Code 1969, § 15.12.120; Ord. No. 870-2010, § 2, 1-18-2011; Ord. No. 925-2014, § 2, 7-21-2014)