Chapter 15.90
CITY OF NORCO GRADING REQUIREMENTS
Sections:
15.90.010 Administration and Enforcement
15.90.030 Protection of Adjacent Property
15.90.080 Soils Engineering and Engineering Geology Reports
15.90.130 Drainage and Terracing
15.90.010 Administration and Enforcement
APPENDIX CHAPTER J, GRADING is adopted as the City of Norco’s Grading Requirements along with the following amendments:
Section J101.3 Is added to read as follows:
J101.3 Administration and Enforcement. For the purpose of the administration and enforcement of this Appendix Chapter, Grading, the Building Official shall mean the City Engineer or their designated representative.
15.90.020 General Hazards
Section J101.4 Is added to read as follows
J101.4 General Hazards. Whenever the City Engineer determines that any existing excavation, 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 the City Engineer may give written notice thereof to the owner of the property upon which the excavation, embankment or fill is located, or other person or agent in control of said property. Upon receipt of said notice, the owner or other person or agent in control of the property shall repair or eliminate such excavation, embankment or fill so as to eliminate the hazard, in conformance with the requirements of this code, within the period specified in said notice.
15.90.030 Protection of Adjacent Property
Section J101.6 Is added to read as follows
J101.6 Protection of Adjacent Property. The permittee and the owner of the property on which the grading is performed shall be responsible for the prevention of damage to adjacent property. 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 taking adequate measures to support and protect such property from settling, cracking or other damage that might result. Any person performing any grading that involves imported or exported materials shall take special precautions, as approved by the City Engineer, to prevent such materials from being deposited on the adjacent public way and/or drainage courses.
15.90.040 Exemptions
Section J103.2 Exemptions. Is revised to add the following exemptions.
J103.2 Exemptions. A grading permit shall not be required for the following:
8. An excavation that does not exceed 60 cubic yards (45.8 m3) and complies with one of the following conditions:
(a) is less than 2 feet (0.6 m) in depth.
(b) does not create a cut slope greater than 5 feet (1.5 m) measured vertically upward from the cut surface to the surface of the natural grade and is not steeper than 2 units horizontal to 1 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 1 foot (0.3 m) in depth and is placed on natural terrain with a slope flatter than 5 units horizontal to 1 unit vertical (20 percent slope).
(b) is less than 3 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 steeper than 2 units horizontal to 1 unit vertical (50 percent slope).
(c) Is less than 5 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 2 units horizontal to 1 unit vertical (50 percent slope).
(Ord. 985 Sec. 1, 2015)
15.90.050 Grading Fees
J103.5 Grading Fees. Fees shall be assessed in accordance with the provisions of this section. The amount of the fees shall be as specified in Section 108 of this code.
1. Plan Review Fees. When a plan or other data are required to be submitted, a plan review fee shall be paid at the time of submitting plans and specifications for review. Separate plan review fees shall apply to retaining walls or major drainage structures as required elsewhere in this code. For excavation and fill on the same site, the fee shall be based on the volume of excavation or fill, whichever is greater.
2. Permit Fees. A fee for each grading permit shall be paid to the City Engineer at the time of issuance of the permit. Separate permits and fees shall apply to retaining walls or major drainage structures as required elsewhere in this code.
3. Site Inspection Fee. When the City Engineer finds that a visual inspection of the site is necessary to establish drainage requirements for the protection of property, existing buildings or the proposed construction, a site inspection shall be made during plan check of grading plans. A fee for such inspection shall be paid to the City Engineer at the time of submitting plans and specifications for review.
15.90.060 Grading Security
Section J103.7 Grading Security. Is added to read as follows:
J103.7.1 Purpose. The City Engineer may require permittees or owners to provide security, as a condition of the issuance of a grading permit, in an amount sufficient to mitigate the hazardous conditions that may be created if the grading is not completed in accordance with the approved plans and specifications.
J103.7.2 Security Required A permit shall not be issued for grading involving more than 1,000 cubic yards (764.6 m3) unless the owner posts with the City Engineer a security in an amount determined by the City Engineer in accordance with Section J103.7.3 and in one of the following forms:
1. A bond furnished by a corporate surety authorized to do business in this state.
2. A cash bond.
3. Savings and loan certificates or shares deposited and assigned to the City
4. An instrument of credit from a financial institution subject to regulation by the state or federal government and pledging that the funds necessary to carry out the grading are on deposit and guaranteed for payment, or a letter of credit issued by such a financial institution.
Where unusual conditions or special hazards exist, the City Engineer may require security for grading involving less than 1,000 cubic yards (764.6 m3). Security required by this Section may include incidental off-site grading on property contiguous with the site to be developed, provided written consent of the owner of such contiguous property is filed with the City Engineer.
The City Engineer may waive the requirements for a security for the following:
1. Grading being done by or for a governmental agency.
2. Grading necessary to remove a geotechnical hazard,
3. Grading on a site, not exceeding a slope of three horizontal to one vertical, provided such grading as determined by the City Engineer will not affect drainage from or to adjacent properties.
4. Filling of holes or depressions, provided such grading will not affect the drainage from or to adjacent properties.
J103.7.3 Amount of Security. The amount of security shall be based on the number of cubic yards of material in excavation or fill, whichever is greater, and the cost of all drainage or other protective devices or work necessary to eliminate potential geotechnical hazards. That portion of the security valuation based on the volume of material in either excavation or fill shall be computed as follows:
A) 100,000 cubic yards or less—50 percent of the estimated cost of grading work, or
B) Over 100,000 cubic yards—50 percent of the cost of the first 100,000 cubic yards plus 25 percent of the estimated cost of that portion in excess of 100,000 cubic yards.
When the rough grading has been completed in conformance with the requirements of this code, the City Engineer may, at his or her discretion, consent to a proportionate reduction of the security to an amount estimated to be adequate to ensure completion of the grading work, site development or planting remaining to be performed. The costs referred to in this section shall be as estimated by the City Engineer.
J103.7.4 Conditions. All security shall include the conditions that the principal shall:
1. Comply with all of the provisions of this code, applicable laws, and ordinances;
2. Comply with all of the terms and conditions of the grading permit;
3. Complete all of the work authorized by the permit.
J103.7.5 Term of Security The term of each security shall begin upon the filing with the City Engineer and the security shall remain in effect until the work authorized by the grading permit is completed and approved by the City Engineer.
J103.7.6 Default Procedures. In the event any grading for which a permit has been issued is not completed in accordance with the approved plans and specifications for said work or with all terms and conditions of the grading permit, the City Engineer
may declare that a default has occurred. The City Engineer shall give notice thereof to the principal and surety or financial institution executing the security, or to the owner in the case of a cash bond or assignment. The City Engineer may thereafter determine the work that is necessary to mitigate any hazardous or unsafe conditions on the site and cause such work to be performed. Where the security consists of a bond or instrument of credit, the surety or financial institution executing the security shall be responsible for the payment of all costs and expenses incurred by the City Engineer in causing such work to be performed, up to the full amount of the security. In the case of a cash bond or assignment, the City Engineer may pay all costs and expenses incurred in causing such work to be performed from the funds deposited, and return any unused portion of such deposit or funds to the person making said deposit or assignment.
15.90.070 Grading Designation
Section J104.2.1 is added to read as follows:
J104.2.1 Grading Designation. Grading in excess of 5,000 cubic yards (3825 m3) or that is proposed to support any structure shall be designated as “engineered grading.” All engineered grading shall be performed in accordance with an approved grading plan and specifications prepared by a civil engineer, unless otherwise required by the City Engineer.
Grading involving less than 5,000 cubic yards (3825 m3) and that will not support any structure shall be designated “regular grading” unless the permittee chooses to have the grading be designated as engineered grading, or the City Engineer determines that, due to the existence of special conditions or unusual hazards, the grading should be designated as engineered grading.
Section J104.2.2 is added to read as follows:
J104.2.2 Regular Grading Requirements. In addition to the provisions of Section 106, and Section 104.2, 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 (4.6 m) of the proposed grading.
4. Contours, flow areas, elevations, or slopes which define existing and proposed drainage patterns.
Section J104.2.3 is added to read as follows:
J104.2.3 Engineered Grading Requirements. In addition to the provisions of Section 106, and Section J104.2, an application for a permit for engineered grading shall be accompanied by four sets of plans and specifications, and supporting data consisting of a soils engineering report and engineering geology report.
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 shall show in detail that the proposed work 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 depict the location of the proposed work, the name and address of the owner, and the person by whom they were prepared.
The plans shall include or be accompanied by the following information:
1. General vicinity of the proposed site.
2. Property limits and accurate contours of existing ground and details of terrain and area drainage.
3. Limiting dimensions, elevations, or finish contours to be achieved by the grading, proposed drainage channels, and related construction.
4. 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.
5. Location of any existing or proposed buildings or structures located on the property on which the work is to be performed and the location of any buildings or structures on adjacent properties that are within 15 feet (4.6 m) of the property or that may be affected by the proposed grading operations.
6. Recommendations in the soils engineering report and the engineering geology report shall be incorporated into the grading plans or specifications. When approved by the City Engineer, specific recommendations contained in the soils engineering report and the engineering geology report, that are applicable to grading, may be included by reference.
7. 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.
8. A statement of the quantities of material to be excavated and/or filled. Earth work quantities shall include quantities for geotechnical and geological remediation. In addition, a statement of the quantities of material to be imported or exported from the site.
9. A statement of the estimated starting and completion dates for proposed work.
10. 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, when the City Engineer requires that such professional persons be so employed. These acknowledgments shall be on a form furnished by the City Engineer.
11. A drainage plan for those portions of property proposed 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.
12. Location of existing and proposed utilities, drainage facilities, and recorded public and private easements.
15.90.080 Soils Engineering and Engineering Geology Reports
Section J104.3 is added to read as follows:
J104.3 Soils Engineering and Engineering Geology Reports. The soils engineering report required by Section J104.2.3 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 an opinion on the 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. All reports shall conform to the requirements of Section 111 of this Code and shall be subject to review by the City Engineer. Supplemental reports and data may be required as the City Engineer may deem necessary. Recommendations included in the reports and approved by the City Engineer shall be incorporated in the grading plan or specifications.
The engineering geology report required by Section J104.2.3 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 an 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. All reports shall conform to the requirements of Section 111 of this Code and shall be subject to review by the City Engineer. Supplemental reports and data may be required as the City Engineer may deem necessary. Recommendations included in the reports and approved by the City Engineer shall be incorporated in the grading plan or specifications.
EXCEPTION:
1. A soils report is not required for single-family dwellings less than 10,000 square feet located in existing recorded subdivision lots.
2. A soils engineering or engineering geology report is not required where the City Engineer determines that the nature of the work applied for is such that a report is not necessary.
15.90.090 Liquefaction study
J104.4 Liquefaction study. For sites with mapped maximum considered earthquake spectral response accelerations at short periods (Ss) greater than 0.5g as determined by Section 1613, a study of the liquefaction potential of the site shall be provided, and the recommendations incorporated in the plans. A geotechnical investigation will be required when the proposed work is a “Project” as defined in California Public Resources Code §2693, and is located in an area designated as a “Seismic Hazard Zone” as defined in Title 14 of the California Code of Regulations §3722 on Seismic Hazard Zone Maps issued by the State Geologist under Public Resources Code §2696.
15.90.100 Inspections
Section J105 is hereby amended, by the deletion of the entire section and the addition of a new section thereto, to read as follows:
Section J105.1 General is added to read as follows:
J105.1 General. Grading inspections shall be governed by Section 109, Appendix Chapter J108 of this code and as indicated herein. Grading operations for which a permit is required shall be subject to inspection by the City Engineer. In addition, professional inspection of grading operations shall be performed 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 City Engineer for regular grading.
Section J105.2 Special and Supplemental inspections is added to read as follows:
J105.2 Special and Supplemental inspections. The special inspection requirements of Section 1704.7 shall apply to work performed under a grading permit where required by the City Engineer. In addition to the called inspections specified in Section 105.7, the City Engineer 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. The City Engineer may require investigations and reports by an approved soil testing agency, Soils Engineer and/or Engineering Geologist, and Field Engineer. Inspection reports shall be provided when requested in writing by the City Engineer.
The City Engineer may require continuous inspection of drainage devices by the Field Engineer in accordance with this section when the City Engineer determines that the drainage devices are necessary for the protection of the structures in accordance with Section 110 of this code.
Section J105.3 Field Engineer is added to read as follows:
J105.3 Field Engineer. The Field Engineer shall provide professional inspection of those parts of the grading project 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 as required by Sections J105.11 and J105.12. If revised grading plans are required during the course of the work they shall be prepared by a Civil Engineer and approved by the Building Official.
Section J105.4 Soils Engineer is added to read as follows:
J105.4 Soils Engineer. The Soils Engineer shall provide professional inspection of those parts of the grading project 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. If conditions differing from the approved soils engineering and engineering geology reports are encountered during grading, the Soils Engineer shall provide revised recommendations to the permittee, the City Engineer and the Field Engineer.
Section J105.5 Engineering Geologist is added to read as follows:
J105.5 Engineering Geologist. The Engineering Geologist shall provide professional inspection of those parts of the grading project within such engineer’s area of technical specialty, which shall include professional inspection of the bedrock excavation to determine if conditions encountered are in conformance with the approved report. If conditions differing from the approved engineering geology report are encountered, the Engineering Geologist shall provide revised recommendations to the soils engineer.
Section J105.6 Permittee is added to read as follows:
J105.6 Permittee. The permittee shall be responsible for ensuring that the grading is performed in accordance with the approved plans and specifications and in conformance with the provisions of this code. The permittee shall engage project consultants, if required under the provisions of this code, to provide professional inspections on a timely basis.
The permittee shall act as a coordinator between the project consultants, the contractor and the City Engineer. In the event of changed conditions, the permittee shall be responsible for informing the City Engineer of such change and shall provide revised plans for approval.
Section J105.7 Required Inspections is added to read as follows:
J105.7 Required Inspections. The permittee shall call for an inspection by the City Engineer at the following various stages of work and shall obtain the approval of the City Engineer prior to proceeding to the next stage of work:
Pre-grade. Before any construction or grading activities occur at the site. Permittee shall schedule a pregrade inspection with the City Engineer. The permittee shall ensure that all project consultants are present at the pre-grade inspection.
Initial. When the site has been cleared of vegetation and unapproved fill and has been scarified, benched or otherwise prepared for fill. No fill shall have been placed prior to this inspection.
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 have been installed; berms have been installed at the top of the slopes; and the statements required by Section J105.12 have been received.
Final. When grading has been completed; all drainage devices necessary to drain the building pad have been installed; slope planting has been established, irrigation systems have been installed; and the as-built plans and required statements and reports have been submitted.
Section J105.8 Notification of Noncompliance is added to read as follows:
J105.8 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 determines that the work is not being done in conformance with this chapter or the approved grading plans, the Field Engineer, Soils Engineer or the Engineering Geologist shall immediately report, in writing, the discrepancies and the recommended corrective measures to the permittee and to the City Engineer.
Section J105.9 Transfer of Responsibility is added to read as follows:
J105.9 Transfer of Responsibility. If the Field Engineer, the Soils Engineer, or the Engineering Geologist of record is changed after grading has commenced, the City Engineer may stop the grading until the permittee has identified a replacement and the replacement has agreed in writing to assume responsibility for those parts of the grading project that are within the replacement’s area of technical competence. It shall be the duty of the permittee to notify the City Engineer in writing of such change prior to the recommencement of such grading.
Section J105.10 Non-inspected grading is added to read as follows:
J105.10 Non-inspected grading. No person shall own, use, occupy or maintain any non-inspected grading. For the purposes of this code, non-inspected grading shall be defined as any grading for which a grading permit was first obtained, pursuant to Section J103, supra, but which has progressed beyond any point requiring inspection and approval by the City Engineer without such inspection and approval having been obtained.
Section J105.11 Routine Field Inspections and Reports is added to read as follows:
J105.11 Routine Field Inspections and Reports. Unless otherwise directed by the Building Official, the Field Engineer for all engineered grading projects shall prepare routine inspection reports and shall file these reports with the City Engineer as follows:
1. Bi-weekly during all times when grading of 400 cubic yards or more per week is occurring on the site;
2. Monthly, at all other times; and
3. At any time when requested in writing by the City Engineer.
Such reports shall certify to the City Engineer that the Field Engineer has inspected the grading site and related activities and has found them in compliance with the approved grading plans and specifications, the building code, all grading permit conditions, and all other applicable ordinances and requirements. The reports shall conform to a standard “Report of Grading Activities” form which shall be provided by the City Engineer.
Section J105.12 Completion of work is added to read as follows:
J105.12 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 otherwise required by the City Engineer:
1. An “As-Built” grading plan prepared by the Field Engineer retained to provide such services in accordance with Section J105.3 showing all plan revisions as approved by the City Engineer. 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 As-Built grading plan shall be accompanied by a certification by the Field Engineer that to the best of his or her knowledge, the work within the Field Engineer’s 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 Section J105.4, 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 investigation report. The report shall include a certification by the Soils Engineer that, to the best of his or her knowledge, the work within the Soils Engineer’s area of responsibility is in accordance with the approved soils engineering report and applicable provisions of 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.
3. A report prepared by the Engineering Geologist retained to provide such services in accordance with Section J105.5, including a final description of the geology of the site and any new information disclosed during the grading and the effect of such new information, if any, on the recommendations incorporated in the approved grading plan. The report shall contain a certification by the Engineering Geologist that, to the best of his or her knowledge, the work within the Engineering Geologist’s area of responsibility is in accordance with the approved engineering geology report and applicable provisions of 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 shall 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 certify, on a form prescribed by the City Engineer, that the grading conforms to said as-built plan and the approved specifications.
Section J105.13 Notification of completion is added to read as follows:
J105.13 Notification of completion. The permittee shall notify the City Engineer 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 all required reports have been submitted and approved.
Section J105.14 Change of Ownership is added to read as follows:
J105.14 Change of Ownership. Unless otherwise required by the City Engineer, when a grading permit has been issued on a site and the owner sells the property prior to final grading approval, the new property owner shall be required to obtain a new grading permit.
15.90.110 Fills
Section J107 Fills is hereby amended, by the deletion of the entire section and the addition of a new section thereto, to read as follows:
Section J107.1 General is added to read as follows:.
J107.1 General. Unless otherwise recommended in the soils report, fills shall conform to provisions of this section.
EXCEPTION: The City Engineer may permit a deviation from the provisions of this chapter for minor fills not intended to support structures, where no soils engineering report has been prepared.
Section J107.2 Surface Preparation of Ground is added to read as follows:.
J107.2 Surface Preparation of Ground. Fill slopes shall not be constructed on natural slopes steeper than 2 units horizontal to 1 unit vertical (50 percent slope). The ground surface shall be prepared to receive fill by removing vegetation, topsoil and other unsuitable materials (including any existing fill that does not meet the requirements of this chapter), and scarifying the ground to provide a bond with the fill material.
Subdrains shall be provided under all fills placed in natural drainage courses and in other locations where seepage is evident, except where the Soils Engineer or Engineering Geologist recommends otherwise. Such sub-drainage systems shall be of a material and design approved by the Soils Engineer and acceptable to the City Engineer.
The Soils Engineer shall provide continuous inspection during the process of subdrain installations. The location of the subdrains shall be shown on a plan prepared 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.
Section J107.3 Benching is added to read as follows:.
J107.3 Benching. Where existing grade is at a slope steeper than 5 units horizontal to 1 unit vertical (20 percent) and the depth of the fill exceeds 5 feet (1524 mm 1.5 m) benching shall be provided into sound bedrock or other competent material as determined by the Soils Engineer. The ground preparation shall be in accordance with Figure J107.3 or as determined by the Soils Engineer. When fill is to be placed over a cut, a key shall be provided which is at least 10 feet (3048 mm 3.0 m) in width and 2 feet (610 mm0.6 m) in depth. The area beyond the toe of fill shall be sloped for sheet overflow or a paved drain shall be constructed thereon. The Soils Engineer or Engineering Geologist or both shall inspect and approve the cut as being suitable for the foundation and placement of fill material before any fill material is placed on the excavation.
Section J107.4 Fill material is added to read as follows:
J107.4 Fill material. Fill material shall not include organic, frozen or other deleterious materials. Unless approved by the City Engineer, no rock or similar irreducible material greater than 12 inches (305 mm 0.3 m) in any dimension shall be included in fills.
EXCEPTION: The City Engineer may permit placement of larger rock when the soils engineer properly devises and recommends a method of placement, and continuously inspects the placement and approves the fill stability. The following requirements shall also apply:
1. Prior to issuance of the grading permit, potential rock disposal areas shall be delineated on the grading plan.
2. Rock sizes greater than 12 inches (0.3 m) in maximum dimension shall be 10 feet (3.0 m) or more below grade, measured vertically.
3. Rocks shall be placed so as to assure filling of all voids with well-graded soil.
4. 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.
5. The location of oversized rock dispersal areas shall be shown on the as-built plan.
Section J107.5 Compaction is added to read as follows:
J107.5 Compaction. All fill material shall be compacted to a minimum of 90 percent of maximum density as determined by ASTM D 1557, Modified Proctor, in lifts not exceeding 12 inches (305 mm 0.3 m) in depth within 40 feet (12.2 m) below finished grade and 93 percent of maximum dry density deeper than 40 feet (12.2 m) below finished grade, unless a lower relative compaction (not less than 90 percent of maximum dry density) is justified by the soils engineer and approved by the City Engineer. Where ASTM D 1557, Modified Proctor is not applicable, a test acceptable to the Building Official shall be used.
Field density shall be determined by a method acceptable to the City Engineer. However, not less than ten percent of the required density tests, uniformly distributed, shall be obtained by the Sand Cone Method. Fill slopes steeper than 2 units horizontal to 1 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 City Engineer that the angle of slope, construction method and other factors will comply with the intent of this Section.
Section J107.6 Maximum fill slope is added to read as follows:
J107.6 Maximum Fill Slope. The slope of fill surfaces shall be no steeper than is safe for the intended use. Fill slopes steeper than 2 units horizontal to 1 unit vertical (50 percent) shall be justified by soils engineering reports or engineering data conforming with the requirements of Section 111, containing a statement by the soils engineer that the site has been investigated and an opinion that a steeper fill slope will be stable and will not create a hazard to public or private property. Substantiating calculations and supporting data may be required where the City Engineer determines that such information is necessary to verify the stability and safety of the proposed slope. The City Engineer may require the fill slope to be constructed with a face flatter in slope than 2 units horizontal to 1 unit vertical (50 percent slope) if the City Engineer finds it necessary for stability and safety of the slope.
Section J107.7 Slopes to Receive Fill is added to read as follows:
J107.7 Slopes to Receive Fill. Where fill is to be placed above the top of an existing slope steeper than 3 units horizontal to 1 unit vertical (33 percent slope), the toe of the fill shall be set back from the top edge of the existing slope a minimum distance of 6 feet (1.8 m) measured horizontally or such other distance as may be specifically recommended by a Soil Engineer or Engineering Geologist and approved by the City Engineer.
Section J107.8 Inspection of Fill is added to read as follows:
J107.8 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 to ensure that the work is 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 provide continuous inspection during the entire fill placement and compaction of fills that will exceed a vertical height or depth of 30 feet (9.1 m) or result in a slope surface steeper than 2 units horizontal to 1 unit vertical (50 percent slope).
Section J107.9 Testing of Fills is added to read as follows:
J107.9 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 Section J112 Referenced Standards.
15.90.120 Setbacks
Section J108 is hereby amended, by the deletion of the entire section and the addition of a new section thereto, to read as follows:
Section J108.1 General is added to read as follows:
J108.1 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 J108.1, unless substantiating data is submitted justifying reduced setbacks and reduced setbacks are recommended in a soils engineering and engineering geology report approved by the City Engineer.
Section J108.2 Top of slope is added to read as follows:
J108.2 Top of Slope. The setback at the top of a cut slope shall not be less than that shown in Figure J108.1, or than is required to accommodate any required interceptor drains, whichever is greater. For graded slopes the property line between adjacent lots shall be at the apex of the berm at the top of the slope. Property lines between adjacent lots shall not be located on a graded slope steeper than 5 units horizontal to 1 unit vertical (20 percent slope).
Section J108.3 Toe of Fill Slope is added to read as follows:
J108.3 Toe of Fill Slope. The setback from the toe of a fill slope shall not be less than that shown by figure J108.1. 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 J108.1.
2. Provisions for retaining walls or similar construction.
3. Erosion protection of the fill slopes.
4. Provision for the control of surface waters
Section J108.4 Alternate Setbacks is added to read as follows:
J108.4 Alternate Setbacks. The City Engineer may approve alternate setbacks if he or she determines that no hazard to life or property will be created or increased. The City Engineer may require an investigation and recommendation by a qualified engineer or engineering geologist to justify any proposed alternate setback.
15.90.130 Drainage and Terracing
Section J109 is hereby amended, by the deletion of the entire section and the addition of a new section thereto, to read as follows:
Section J109.1 General is added to read as follows:
J109.1 General. Unless otherwise recommended by a Civil Engineer and approved by the City Engineer, drainage facilities and terracing shall be provided in accordance with the requirements of Section J109.2 for all cut and fill slopes steeper than 3 units horizontal to 1 unit vertical (33 percent slope).
For slopes flatter than 3 units horizontal to 1 unit vertical (33 percent slope) and steeper than 5 units horizontal to 1 unit vertical (20 percent slope) a paved swale or ditch shall be installed at 30 foot (9.1 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 Section J109.5. Swales must be paved with reinforced concrete not less than 3 inches (0.08 m) in thickness, reinforced with 6-inch (0.2 m) by 6-inch (0.2 m) No.10 by No.10 welded wire fabric or equivalent reinforcing centered in the concrete slab or an equivalent approved by the City Engineer. Swales must have a minimum flow line depth of 1 foot (0.3 m) and a minimum paved width of 18 inches (0.5 m). Swales shall have a minimum gradient of not less than 5 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.
Section J109.2 Drainage Terraces is added to read as follows:
J109.2 Drainage Terraces. Drainage terraces at least 8 feet (2.4 m) in width shall be established at not more than 30 foot (9.1 m) vertical intervals on all cut or fill slopes to control surface drainage and debris. When only one terrace is required, it shall be at midheight. For cut or fill slopes greater than 100 feet (30.5 m) and up to 120 feet (36.6 m) in vertical height, one terrace at approximately midheight shall be 20 feet (6.1 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 City Engineer. Suitable access shall be provided to permit proper cleaning and maintenance.
Drainage swales on terraces shall have a longitudinal grade of not less than 5 percent or more than 12 percent and a minimum depth of 1 foot (0.3 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. Drainage swales must be paved with reinforced concrete not less than 3 inches (0.08 m) in thickness, reinforced with 6-inch (0.2 m) by 6-inch (0.2 m) No. 10 by No. 10 welded wire fabric or equivalent reinforcing centered in the concrete slab or an approved equal paving. Drainage swales shall have a minimum depth at the deepest point of 1 foot (0.3 m) and a minimum paved width of 5 feet (1.5 m). Drainage terraces exceeding 8 feet (2.4 m) in width need only be so paved for a width of 8 feet (2.4 m) provided such pavement provides a paved swale at least 1 foot (0.3 m) in depth. Downdrains or drainage outlets shall be provided at approximately 300-foot (91.4 m) intervals along the drainage terrace or at equivalent locations. Downdrains 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 Section J109.5.
Section J109.3 Interceptor Drains and Overflow Protection is added to read as follows:
J109.3 Interceptor Drains and Overflow Protection. 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 4 feet (1.2 m) from the top of the slope.
Interceptor drains shall be installed along the top of graded slopes greater than 5 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 1 foot (0.3 m) and a minimum width of 3 feet (0.9 m). The slope shall be approved by the Building Official, but shall not be less than 50 units horizontal to 1 unit vertical (2 percent). The drain shall be paved with concrete not less than 3 inches (0.08 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 City Engineer.
Section J109.4 Drainage across Property Lines is added to read as follows:
J109.4 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 non-erosive down drains or other devices.
Section J109.5 Disposal is added to read as follows:
J109.5 Disposal. All drainage facilities shall be designed to convey waters to the nearest practicable street, storm drain, or natural watercourse or drainage way approved by the City Engineer or other appropriate governmental agency provided that the discharge of such waters at that location will not create or increase a hazard to life or property. Erosion of the ground in the area of discharge shall be prevented by installation of non-erosive down drains or other devices. Desilting basins, filter barriers or other methods, as approved by the City Engineer, 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 dissipator may be required.
Building pads shall have a minimum drainage gradient of 2 percent toward an approved drainage facility or a public street unless otherwise directed by the City Engineer. A lesser slope may be approved by the City Engineer for sites graded in relatively flat terrain, or where special drainage provisions are made, when the City Engineer finds such modification will not result in a hazard to life or property.
Section J109.5.1 Minimum Gradients is added to read as follows:
J109.5.1 Minimum Gradients Except on slopes, drainage devices shall be constructed with minimum gradients as follows: Poured in place cement concrete construction – 0.5%; Shotcrete concrete construction – 0.5%; Asphaltic concrete pavement – 1.0%; Soils swales – 0.5%; Pipes – 0.4%.
Section J109.5.2 Slopes is added to read as follows:
J109.5.2 Slopes Drainage devices constructed on slopes shall have a minimum gradient of five percent (5.0%). Such drainage devices shall be constructed of shotcrete or poured in place concrete with suitable reinforcement. Closed piping, unpaved swales and Asphaltic concrete drainage structures shall not be used for slope drainage.
Section J109.5.3 Erosion Prevention is added to read as follows:
J109.5.3 Erosion Prevention Drainage devices shall be constructed to convey drainage to an established private or public watercourse, channel, storm drain or public street, and shall be designed to prevent erosion.
Section J109.5.4 Device design is added to read as follows:
J109.5.4 Device design. Drainage devices conveying water to the public streets shall drain over driveway approaches, through curb drains, through sidewalk culverts, or through non-concentrated sheet flow over the curb as designated by the City Engineer.
15.90.140 Erosion Control
Section J110 is hereby amended, by the deletion of the entire section and the addition of a new section thereto, to read as follows:
Section J110.1 General is added to read as follows:
J110.1 General. The faces of cut and fill slopes shall be prepared and maintained to control erosion. This control shall be permitted to consist of effective planting. This control shall consist of effective planting, erosion control blankets, soil stabilizers or other means as approved by the City Engineer.
EXCEPTION: Erosion control measures need not be provided on cut slopes not subject to erosion due to the erosion-resistant character of the materials as approved by the Project Consultants, to the satisfaction of the City Engineer.
Section J110.2 Other Devices is added to read as follows:
J110.2 Other Devices. Where necessary, check dams, cribbing, riprap or other devices or methods shall be employed to control erosion and provide safety.
Section J110.3 Planting is added to read as follows:
J110.3 Planting. The surface of all cut slopes more than 5 feet (1.5 m) in height and fill slopes more than 3 feet (9.1 m) in height shall be protected against damage from erosion by planting with grass or ground cover plants. Slopes exceeding 15 feet (4.6 m) in vertical height shall also be planted with shrubs, spaced at not to exceed 10 feet (3.0 m) on centers; or trees, spaced at not to exceed 20 feet (6.1 m) on centers; or a combination of shrubs and trees at an equivalent spacing, in addition to the grass or ground cover plants. 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.
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. Modifications to planting must be approved by the City Engineer prior to installation.
Section J110.4 Irrigation is added to read as follows:
J110.4 Irrigation. Slopes required to be planted by Section J 110.3 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 to and approved by the City Engineer prior to installation. A functional test of the system may be required.
For slopes less than 20 feet (6.1 m) in vertical height, hose bibs to permit hand watering will be acceptable if such hose bibs are installed at conveniently accessible locations where a hose no longer than 50 feet (15.2 m) is necessary for irrigation.
Irrigation requirements 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, plant types, planting methods, fire retardant characteristics, water efficiency, maintenance needs, and other regulatory requirements. Recommendations must include a finding that the alternative irrigation method will sustain the proposed planting and provide a permanent and effective method of erosion control. Modifications for irrigation systems must be approved by the City Engineer prior to installation.
Section J110.5 Plans and Specifications is added to read as follows:
J110.5 Plans and Specifications. Planting and irrigation plans shall be submitted for slopes required to be planted and irrigated pursuant to Sections J110.3 and J110.4. Except as otherwise required by the City Engineer for minor grading, the plans for slopes 20 feet (6.1 m) or more in vertical height shall be prepared and signed by a civil engineer or landscape architect.
If requested by the City Engineer, planting and irrigation details shall be included on the grading plan.
Section J110.6 Rodent Control is added to read as follows:
J110.6 Rodent Control. Fill slopes shall be protected from potential slope damage by a preventative program of rodent control.
Section J110.7 Release of Security is added to read as follows:
J110.7 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 and there shall be evidence of an effective rodent control program.