Ventura Municipal Code Ch. 12.220 Grading Regulations

A. Plan-Check Fees. For excavation and fill on the same site, the fees shall be based on the volume of the excavation or fill, whichever is greater. Prior to acceptance of plans and specifications for checking, the city engineer shall collect a plan-check fee. Separate permits and fees shall apply to retaining walls or other structures as indicated in the most recent California Building Code as adopted by the city. There shall be no separate charge for standard terrace drains and similar facilities. The fee for a grading permit authorizing additional work to that under a current valid permit shall be the difference between the fee paid for the original permit and the fee calculated for the revised total project. No fee refund will be made.

The amount of the plan-checking fee for the grading plans shall be as set by city council resolution from time to time.

B. Permit Fees. A fee for each grading permit shall be paid prior to the issuance of said permit. Double fees will be assessed where grading has been accomplished without an authorized permit. Fees shall be as set by city council resolution from time to time. (Ord. No. 2017-009, § 1, 5-22-17)

A. Requirements. A permit will not be issued for excavation or fill of more than 500 cubic yards in hillside areas, more than 1,000 cubic yards in other areas, or for work which requires retaining walls, until the permittee shall post with the city engineer a bond for the benefit of the city. The bond shall be executed by the owner and a corporate surety authorized to do business in this state as a surety in an amount sufficient to cover the cost of the project, including corrective work necessary to remove and eliminate geological hazards. All bonds shall be executed on forms obtainable from the city engineer.

Exception: The city engineer may waive the requirement that a bond be posted before a permit is issued as provided in this section if the city engineer determines that no potential hazard would exist if the grading is not completed.

B. Cash or Deposit Agreement in Lieu of Bond. In lieu of a surety bond, the applicant may file a deposit agreement or deposit cash or other security as may be approved by the city, with the city engineer upon the terms and conditions and in an amount equal to that which would be required in the surety bond. The deposit submitted with the cash bond may be in the form of cash or negotiable United States securities. The deposit agreement shall be on forms approved by the city engineer.

C. Application of Bond to Adjacent Property. Where grading is required on property adjacent to the grading site under permit to complete a project satisfactorily, written consent must be obtained from the adjacent owner and a copy of the written consent submitted to the city engineer prior to commencement of grading on the adjacent property. The owner of such adjacent property need not provide an additional grading bond if the original is of sufficient amount to include such additional grading.

D. Conditions of the Bond, Deposit Agreement, or Cash Deposit. Every bond, deposit agreement or cash deposit shall be conditioned such that the permittee shall:

1. Comply with all of the provisions of this division and all other applicable laws and ordinances.

2. Comply with all of the terms and conditions of the permit for excavation and fill to the satisfaction of the city engineer.

E. Period and Termination of Bond, Deposit Agreement, or Cash Deposit. The term of each security shall begin upon the date of filing with and shall remain in effect until the completion of the work to the satisfaction of the city engineer, plus an additional period of one year. Such completion shall be evidenced by issuance of a final grading certificate signed by the city engineer. In the event of failure to complete the work or failure to comply with all of the conditions and terms of the permit, the city engineer may order the work to be completed as required by the permit and to the satisfaction of their office. The surety executing such bond or such deposit shall continue to be firmly bound under a continuing obligation for the payment of all necessary costs and expenses that may be incurred or expended by the city in causing any and all of such required work to be accomplished, and that said surety or the depositor assents to any lawful extensions of time within which to construct and complete such work. In the case of a cash deposit or deposit agreement, any unused portion shall be refunded to the permittee.

After the work has been completed to the satisfaction of the city engineer, the city engineer may release or exonerate the bond, deposit agreement, or cash deposit earlier than the additional one-year period if the city engineer determines that the public health, safety and welfare is not jeopardized. In no case shall the security be released earlier than four months after the grading work has been completed to the satisfaction of the city engineer.

F. Amount of Security. The amount of the security shall be based upon the estimated cost plus 25 percent, as determined by the number of cubic yards of material in either excavation or fill, whichever is the greater amount, and shall include the cost of all retaining walls, drainage structures, erosion control, and other protective devices as may lawfully be required. (Ord. No. 2017-009, § 1, 5-22-17)

Whenever the city engineer determines by inspection that any land or any existing excavation or fill has from any cause become a menace to life or limb, endangers public or private property or affects the safety, usability or stability of a public way, the owner or other entity in legal control of the property concerned shall, upon receipt of written notice thereof from the city engineer, correct such condition in accordance with the provisions of this division and the requirements and conditions set forth in such notice to eliminate the undesirable condition.

The owner, or other person in control of such property shall immediately commence the work required by such notice and shall complete the same within a maximum time of 120 days from the date of such notice unless a shorter period of time for completion has been specified in the notice, in which case the owner or other person shall comply within such time as specified. (Ord. No. 2017-009, § 1, 5-22-17)

A. Permit Issuance. Upon satisfactory preparation, completion, and approval of the grading plan, including the preparation of other associated grading documents (i.e., stormwater pollution prevention plan (SWPPP)/stormwater pollution control plan (SWPCP), operations and maintenance plan, declaration of covenant), posting of acceptable security, and payment of grading permit and stormwater inspection fees, a grading permit may be issued.

B. Prior to Start of Construction.

1. Preconstruction Meeting. Applicant shall hold a preconstruction meeting at the project site to review project and plans. Attendees shall include applicant, applicant’s engineers (civil, soils, geotechnical), grading contractor, and city inspection staff.

2. Notification. For hillside grading, applicant shall provide written notice to nearby properties and those properties along access/haul routes of pending grading in accordance with the noticing requirements of the city’s zoning ordinance (Section 24.560.040). The content of the notice shall be approved by city engineer.

3. Equipment Haul Route. Grading applicant/contractor shall obtain an approved haul route permit for moving any earthmoving equipment on or off the property. A haul route permit shall be obtained from the city’s traffic division. The transportation manager may waive this requirement.

C. Supervision. The permittee shall provide sufficient supervisory control during the grading operation to insure compliance with approved plans and with the San Buenaventura Municipal Code. When required by the city engineer, the permittee shall obtain the services of a geotechnical engineer or soils engineer to monitor the work. The geotechnical engineer and soils engineer shall be properly qualified in accordance with Section 12.210.020 and qualified to perform such services within the city.

D. Safety Precautions During Grading. If, at any stage of work on an excavation or fill, the city engineer determines by inspection that further work as authorized by an existing permit is likely to endanger any person or property, the city engineer may require that plans for such work be amended to include adequate safety precautions as a condition to allow the work to continue. Safety precautions may include, but shall not be limited to, specifying a flatter exposed slope or construction of additional drainage facilities, berms, terracing, compaction, cribbing, retaining walls or buttress fills, slough walls, desilting basins, check dams, benching, wire mesh and guniting, rock fences, revetments or diversion walls.

E. Violations.

1. It shall be unlawful for any person to fail, refuse or neglect to comply with the following provisions:

a. All orders issued by the city engineer or the building official pursuant to the provisions of this division.

b. All conditions imposed on grading permits pursuant to the provisions of this division.

c. All rules and regulations of the city with respect to grading which were in effect at the time the grading permit was issued.

2. Any person, firm or corporation violating any of the provisions of this division shall be deemed guilty of a misdemeanor, and each such person shall be deemed guilty of a separate offense for each and every day or portion thereof during which any violation of any of the provisions of this division is committed, continued, or permitted, and upon conviction of any such violation said person shall be punishable by a fine of not more than $1,000, or by imprisonment for not more than six months, or by both such fine and imprisonment.

3. Stop Work Orders. Whenever any construction or work is being done contrary to the provisions of any law or ordinance, or public or private property is endangered, the city engineer may issue a written notice to the responsible party to stop work on that portion of the work on which the violation has occurred or upon which the danger exists. The notice shall state the nature of the violation or of the danger and no work shall be done on that portion until the violation has been rectified and approval obtained from the city engineer or until, as a condition for continuance of the work, special precautions to eliminate the hazards have been approved and imposed by the city engineer and performed by the permittee.

F. Grading Inspection.

1. All construction or work for which a permit is required shall be subject to inspections by authorized employees of the city, and certain types of work, as determined by the city engineer, shall have either continuous or periodic observation by a civil engineer, soils engineer, or engineering geologist employed by the applicant or property owner as a condition of issuance of the grading permit. Prior to issuing a final grading certificate, an inspection shall be made of all construction or work for which a permit has been issued.

2. Exposure of Work. Whenever any work for which inspections are required is covered or concealed by additional work without having first been inspected, the city engineer may require that such work be exposed for examination. The work of exposing and recovering shall not entail expense to the city of San Buenaventura.

3. Notice. The permittee is required to notify the city engineer 48 hours prior to the start of any work on site. The permittee or the permittee’s agent shall notify the city engineer 24 hours in advance during the construction phase when the grading operation is ready for each of the following inspections listed in subsections (F)(3)(b) through (F)(3)(h) of this section:

a. Pregrade inspection: When the permittee is ready to begin work, but before any grading or brushing is started.

b. Toe inspection: After the natural ground is exposed and prepared to receive fill, but prior to the placement of any fill.

c. Excavation inspection: After the excavation is started, but before the vertical depth of the excavation exceeds 10 feet.

d. Fill inspection: After the fill emplacement is started, but before the vertical height of the lifts exceeds 10 feet.

e. Drainage device inspection: After forms and pipe are in place, but before any concrete is placed.

f. Rough grading: When all rough grading and approximate elevations have been established, including drainage swales, terraces, berms, and other drainage devices necessary for the protection of the building site(s) have been completed. This may be called for at the completion of the rough grading without the necessity of the city engineer having previously reviewed and approved the rough grading soil report(s).

g. Final: When all work, including installation of all drainage structures, other protective devices, and planting and slope stabilization, has been completed and the “as graded” plan and required reports have been submitted.

h. Other inspection: In addition to the called inspections above, the city engineer may make other inspections of any work to ascertain compliance with the provisions of this division and other laws.

4. Special Inspections and Monitoring. Where necessary, the city engineer may require the permittee or property owner to employ:

a. A civil engineer to monitor all grading.

b. A geotechnical/soils engineer to provide either periodic or continuous soils inspection.

c. An engineering geologist to provide geological inspections.

The employment of the above shall not be deemed to render unnecessary any inspections described in this division except that on any work requiring continuous monitoring by a civil engineer, geotechnical engineer or soils engineer, the inspections required by this section may be delegated to the engineer by the city engineer. If said engineer fulfilling engineering responsibility under this section finds that work is not being done in conformance with this division or the plans and specifications approved by the city engineer, the engineer shall immediately notify the person in charge of the grading work and the city engineer in writing of the nonconformity and the corrective measures to be taken.

The engineer monitoring grading work shall immediately notify the city engineer in writing upon the termination of their engineering services.

All work shall immediately stop upon the termination of the services of the engineer whose name appears on the grading permit as having been approved to monitor the grading work, and it shall not commence again until the new approved civil/geotechnical/soils engineer certifies in writing to the city engineer that they have reviewed all phases of the project and are thoroughly familiar with it. Upon receipt of this notice, the city engineer will give written notice that work may proceed.

5. Reports/Certifications. Upon completion of the work, the city engineer shall require the permittee or property owner to have prepared the following reports and information:

a. Rough Grading Certificate.

i. Report from a registered civil engineer certifying the satisfactory completion of rough grading including grading to approximate plan elevations, property line located and staked, cut/fill slopes correctly graded, berms installed, and that the recommendations of any engineering geologist or geotechnical or soils engineer reports have been followed.

ii. A geotechnical/soils engineering report, including a statement that the portion of the work concerning the preparation of the existing ground surface and the placing and compaction of fill is in conformance with the approved plans and the appropriate provisions of this section entitled “Fills.”

The report shall also include the final soil-bearing capacity, a finding as to the expansive characteristics of the soil and the presence of buttress fills on a lot by lot basis, the location of subdrains, and a summary of tests. The location of such tests and the limits of the compacted fill shall be shown on a final plan, which shall also show by plan and cross section the location of any rock disposal areas and/or buttress fills, if such were involved in the grading.

iii. An engineering geological report by an engineering geologist based on the as-graded plan including specific approval of the grading as affected by geological factors. Where necessary, a revised geological map and cross sections including faults and other geologic structures, and any recommendations necessary shall be included.

b. Final Grading Certificate.

i. Report from a registered civil engineer certifying that all grading, lot drainage and drainage facilities have been completed in conformance with the approved plans and this division.

ii. All existing survey monumentation shown on the existing topographic survey to be preserved and/or replaced per city standard details. Developer shall provide the city surveyor with all survey notes and documentation for review and acceptance. All survey monuments must be in place and accepted by the city surveyor prior to final acceptance.

G. Excavations.

1. Height. Cut slopes which exceed 100 feet in vertical height shall be constructed with a minimum of one terrace for each 25 feet in vertical height. The terraces shall be evenly spaced on the slope and shall have a minimum width of 10 feet. The cross section of benches shall be as shown in city standard construction details.

2. Slope. Excavations may be no steeper than is safe for the intended purpose and shall not be made with a cut face steeper in slope than 2:1.

Exception: The city engineer may permit the excavation to be made with a cut face steeper in slope than 2:1, if the applicant provides a current geotechnical report using subsurface exploration by both a geotechnical engineer and an engineering geologist to justify a steeper slope to the satisfaction of the city engineer. The report must specify that the materials making up the slope of the excavation and the underlying bedrock are capable of standing on a steeper slope with a factor of safety of not less than one and one-half for static loads.

3. Excavation Setback Near Foundations. Excavations shall not extend below a line that is projected at an angle of 2:1 from the bottom of the nearest point of any footing or foundation of any building or structure unless such footing or foundation is first properly underpinned or supported against settlement or a civil engineer has determined to the satisfaction of the city engineer that the proposed excavation will not affect the existing structure.

4. Unstable Slopes. If the material of the slope is of such composition and character as to be unstable, considering all types of anticipated loading and moisture conditions, the engineering geologist or soils engineer shall, by testing and analysis, provide specific criteria for its stabilization by reduction of slope angle, buttressing, or by a combination of these or other means so as to produce a stable slope with a factor of safety not less than one and one-half for static loads.

5. Cut Slope Setback. All cut slopes shall be within properties or parcels under one ownership. They shall not be divided horizontally by property lines. Tops of cut slopes shall not be made nearer than one-fifth the height of the cut with a minimum setback of two feet or that which is required to accommodate any interceptor drain to a property line, but need not exceed a horizontal distance of 10 feet. If the city engineer determines that the above is unnecessary because of special conditions, the city engineer may make adjustments as a condition of the grading permit.

6. Interceptor Terraces. On cut slopes exceeding 25 feet in height, interceptor terraces shall be constructed in accordance with city standards. Terraces shall be paved with concrete on cut slopes and shall have a minimum width of eight feet and shall be spaced at maximum intervals of 25 feet measured vertically. Where only one terrace is utilized, it shall be placed at mid-height. All terraces and downdrains must comply with the provisions for “erosion control and drainage devices” set forth in this division.

7. Diverter Terraces. Diverter terraces shall be constructed in accordance with the requirements contained under “erosion control and drainage devices” of this division.

H. Fills.

1. Slope. No fill shall be made which creates any exposed surface steeper in slope than 2:1.

Exception: The city engineer may permit a fill to be made which creates an exposed surface steeper in slope than 2:1 if the applicant shows through an investigation, subsurface exploration, analysis and report of a geotechnical engineer and engineering geologist that the strength characteristics of the material to be used in the fill are such as to produce a safe and stable slope with a factor of safety not less than one and one-half for static loads and the areas on which the fill is to be placed have sufficient strength characteristics to support the fill within reasonable settlement values.

2. Slope Reduction. The city engineer may require that the fill be constructed with an exposed surface flatter than 2:1 if, under the particular conditions, such flatter surface is determined by the city engineer to be necessary for stability or safety.

3. Height. Fill slopes which exceed 100 feet in vertical height shall be constructed with a minimum of one bench for each 100 feet in vertical height. The benches shall be evenly spaced on the slope and shall have a minimum width of 30 feet and shall be constructed in accordance with city standard construction details.

4. Interceptor Terraces. On fill slopes exceeding 25 feet in height, interceptor terraces shall be constructed in accordance with city standard construction details. Terraces shall be spaced at maximum intervals of 25 feet measured vertically. Where only one terrace is utilized, it shall be placed at mid-height. All terraces and downdrains must comply with the provisions for “erosion control and drainage devices” set forth in this division.

5. Placement. Fill slopes shall not be constructed on natural slopes steeper than two units horizontal to one unit vertical. All fills shall be placed, compacted, inspected, and tested in accordance with the following provisions. If the strict enforcement of this section is determined by the city engineer to be unnecessary because of the proposed or probable use of land, the city engineer may waive these requirements.

These requirements shall not be waived when structures are to be supported by the fill or where they are necessary as a safety measure to aid in preventing the saturation, settling, slipping or erosion of the fill.

a. Preparation of Ground. The existing ground surface shall be prepared to receive fill by removing vegetation, noncomplying fill, or other unsuitable material and scarifying the ground to provide a bond with the fill material. Where the slope of the ground surface is 5:1 or steeper, the fill shall be supported by keys and level benches cut into competent material as determined by the geotechnical engineer. The key under the toe of a fill slope steeper than 5:1 shall be at least 10 feet wide and two feet deep into firm native soil or bedrock. The area beyond the toe of fill shall be sloped for sheet overflow or a paved drain shall be provided. When fill is to be placed over a cut, the bench under the toe of fill shall be at least 10 feet wide, but the cut shall be inspected and approved as being suitable for the foundation and placement of fill material by the geotechnical engineer or engineering geologist or both before placing the fill and before acceptance by the civil engineer.

b. Benching. Where existing grade is at a slope steeper than five units horizontal to one unit vertical (20 percent) and the depth of the fill exceeds five feet, benching shall be provided into sound bedrock or other competent material as determined by the geotechnical engineer. When fill is to be placed over a cut, a key shall be provided which is at least 10 feet in width and two feet in depth. The area beyond the toe of fill shall be sloped for sheet overflow or a paved drain shall be constructed thereon. The geotechnical 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.

c. Subdrains. Subdrains shall be provided under all fills placed in natural drainage courses and in other locations where seepage is evident except where the geotechnical engineer or engineering geologist recommends otherwise. Such subdrainage systems shall be of a material and design approved by the geotechnical engineer and acceptable to the city engineer. The geotechnical engineer shall provide continuous monitoring during the process of subdrain installation to conform to approved plans and the geotechnical engineer’s recommendations. Such monitoring shall be done by the soil testing agency employed by the permittee. The locations of the subdrains shall be shown on a plan approved by the geotechnical engineer.

d. Fill Material. Organic material shall not be permitted in fills. No rock or similar irreducible materials with a maximum dimension greater than eight inches shall be buried or placed in fill except as recommended by the geotechnical engineer, approved by the city engineer, and meeting the following requirements:

i. The oversized material shall be placed 10 feet or more below finish grade.

ii. The soils engineer shall be present while the oversized material is placed and covered.

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

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

Rock or similar irreducible materials less than eight inches in greatest dimension shall be placed in such a manner as to prevent nesting of oversize particles and to assure that all voids are filled with fine-grained materials.

v. The fill shall be spread in a series of loose lifts, each not exceeding eight inches in thickness, and shall be compacted by sheepsfoot roller or other approved method after each layer is spread. The next lift shall not be placed until the compacted lift is tested by the soils engineer and authorized by the city engineer.

vi. The moisture content of the fill material shall be controlled at the time of spreading and compaction to obtain required relative compaction. A soils engineer shall establish the allowable moisture range which minimizes settlement.

vii. All fills shall be compacted to a minimum of 90 percent of maximum density as determined by ASTM D 1557, Modified Proctor. The city engineer may approve alternate minimum compaction densities where a soils engineer or geotechnical engineer has determined to the satisfaction of the city engineer that alternate minimum compaction densities are necessary to achieve the maximum benefit from soil consolidation. If the required degree of relative compaction cannot be attained on sloped surfaces, the slope shall be overfilled and cut back until the compacted inner core is exposed. Field density shall be determined by ASTM D 1557, Modified Proctor, or other methods approved by the city engineer which give equivalent results.

viii. A sufficient number of tests shall occur to satisfy the city engineer that all requirements have been met. At a minimum, a field density test, as herein provided, shall be taken for each two feet of fill, or portion thereof, measured vertically from the lowest point of the area to be filled and for each 1,000 cubic yards of fill placed. In addition, in the case of subdivisions, at least one field density test shall be taken on each lot which receives fill. One field density test shall be taken on the slope face for every four feet in elevation of the slope or every 1,000 square feet of slope for each lot.

6. Rough Grading Certificate. All fills regulated by this division shall be tested for relative compaction by a soils testing agency. A certificate of compliance with the terms of this section and the grading permit, setting forth densities, relative compaction and other soil characteristics shall be prepared and signed by a geotechnical engineer. This report shall be submitted to and approved by the city engineer before any final approval of the fill is given and before any foundation construction begins.

7. Toe Location. Fills that toe out on natural slopes which are steeper than 2:1 shall not be permitted.

Exception: The city engineer may permit the placement of fill on slopes as steep as 1-1/2:1, if the applicant shows through subsurface exploration and appropriate analysis by both a geotechnical engineer and an engineering geologist that the material making up the natural slope is capable of supporting the proposed fill.

8. Toe Setback. Toes of fill slopes shall not be made nearer to a project boundary/property line than one-half the height of the fill with a minimum setback of two feet, but need not exceed a horizontal distance of 20 feet. Fill slopes shall not be divided horizontally by property lines. If the city engineer determines that the above is unnecessary because of special conditions, the city engineer may make adjustments as a condition of the grading permit.

9. Combined Cut and Fill Slopes. Combined cut and fill slopes shall meet the requirements of this division insofar as steepness, height, and benching are concerned except that, where the slope exceeds 25 feet in height, the required terrace shall be placed at the mid-height location of the cut slope or as determined by the geotechnical engineer.

10. Old Fills. All existing human-made fills on any and all sites will be properly evaluated and recommendations and design criteria for corrective measures shall be included within the soils engineering report, if deficiencies exist.

11. Progress Reports. Periodic soils reports by a geotechnical engineer certifying the compaction or acceptability of all fills will be required monthly for projects extending three months or longer. These shall include, but need not be limited to, inspection of cleared areas and benches prepared to receive fill, removal of soil and unsuitable materials, the placement and compaction of fill materials, and the inspection of buttress fills, subdrains, and similar devices.

The city engineer may require sufficient inspection by an engineering geologist to assure all geologic conditions have been adequately considered. Where geologic conditions warrant, the city engineer may require periodic geologic reports. These inspections and reports may be required to include, but need not be limited to, inspection of cut slopes, canyons during clearing, operations for groundwater and earth material conditions, placement of subdrains, benches prior to placement of fill, and possible spring locations.

I. Planting and Irrigation of Cut and Fill Slopes.

1. General. All fill and cut slopes greater than four feet in vertical height, and any natural slopes from which native vegetation has been removed, which are determined by the city engineer to be subject to erosion, shall be planted and irrigated with an irrigation system to promote the growth of ground cover plants to protect the slopes against erosion, as required by this section. The owner shall be responsible for planting and maintaining all slopes where such is required in this section.

2. Minimum Requirements.

a. Low Slopes to 15 Feet in Vertical Height.

i. Plant with grass or ground cover plants as recommended on the approved planting schedule. Other plants recommended by a landscape architect will be considered for approval by the parks manager.

ii. An irrigation system shall be installed to irrigate these slopes as a part of the on-site plumbing installation, unless otherwise approved by the city engineer.

iii. The owner shall water the slopes which have been planted with grasses and ground cover plants at sufficient time intervals to promote growth.

Exception: Where the city engineer finds the slope is located in such an area to make hand-watering possible, conveniently located hose bibs will be accepted in lieu of the required irrigation system when a hose no longer than 50 feet would be necessary.

b. Medium Slopes 15 Feet to 38 Feet in Vertical Height.

i. Plant with grass or ground cover plants as recommended on the approved planting schedule. Other plants may be recommended by a landscape architect for approval by the parks manager.

ii. In addition to ground cover plants, approved shrubs having a one-gallon minimum size at 10 feet on center in both directions on the slope may be used in conjunction with an irrigation system. The plants and planting pattern may be varied to include trees upon the recommendation of a landscape architect and approved by the parks manager.

iii. An adequate irrigation system shall be installed during grading, prior to planting of shrubs and trees.

c. High Slopes 38 Feet or Over in Vertical Height.

i. Plant with grass or ground cover plants as recommended on the approved schedule. Other plants recommended by a landscape architect may be submitted to the parks manager for approval.

ii. In addition to ground cover plants, approved shrubs having a minimum one-gallon size at 10 feet on center in both directions on the slope or trees at 20 feet on center both ways may be used.

A combination of shrubs and trees may be utilized. This plant and planting pattern may be varied upon the recommendation of a landscape architect and approval by the parks manager.

iii. Slopes exceeding a height where a drainage terrace is required shall be planted with shrubs, minimum size one gallon, two feet on center, parallel to the benches and within two feet of the uphill side. Larger varieties may be staggered one each side of the bench as an alternative.

iv. An adequately designed irrigation system shall be installed prior to planting shrubs and trees.

3. Special Requirements for Irrigation Systems.

a. Plans for irrigation systems shall be submitted to and approved by the parks manager prior to installation.

b. The irrigation system shall be designed to provide a uniform water coverage at a rate of precipitation of not less than one-tenth inch per hour nor more than three-tenths inch per hour on the planted slope. In no event shall the rate of precipitation duration of sprinkling be permitted to create a saturated condition and cause an erosion problem, or allow the discharge of excess water into any public or private street.

c. A check valve and balance cock shall be installed in the system where drainage from sprinkler heads will create an erosion problem.

d. Adequate backflow protection shall be installed in each irrigation system as required by the California Plumbing Code.

e. A function test of the irrigation system shall be performed by the installer for every irrigation system prior to approval.

f. Where PVC pipes are used on slopes, they shall be a minimum of schedule 40 embedded at least eight inches below grade. Such pipes may be exposed for above-ground installation provided they are ASTM rated as resistant to ultraviolet sunlight. All risers, sprinkler heads, valves and fittings shall be brass or galvanized metal, or rated as sunlight resistant.

4. Plants. All plants required by this section shall be selected from a list approved by the parks manager.

J. Erosion Control and Drainage Devices.

1. Water Disposal. All drainage facilities shall be designed to carry waters to the nearest practicable drainage way approved by the city engineer as a safe place to deposit such waters. Erosion of ground in the area of discharge shall be prevented by installation of nonerosive downdrains or other devices.

2. Interceptor Terraces. Paved (concrete) interceptor terraces shall have a minimum width of eight feet, a minimum depth of one foot, and shall be installed on the face of all cut and fill slopes at intervals not to exceed 25 feet measured along a vertical plane.

The longitudinal slope of interceptor terraces shall not be less than four percent or more than 12 percent, and any change in rate of grade within these allowable slopes shall increase the grade in the direction of flow.

A single run of a terrace shall not exceed 150 feet to a downdrain.

Downdrains shall be embedded and round pipes enclosed in concrete shaped as shown in the city standard construction details, or an alternate design which is prepared by a civil engineer and acceptable to the city engineer.

The cross section of interceptor terraces shall meet the specifications shown in the city standard construction details.

3. Diverter Terraces. Paved (concrete) diverter terraces, three feet in width and one foot in depth, constructed as shown in the city standard construction details, shall be installed at the top of all cut slopes where the tributary drainage area above has a slope exceeding 10 horizontal to one vertical and a horizontal projection of greater than 40 feet.

4. Berms. Berms as shown in the city standard construction details shall be constructed at the top of all slopes.

5. Vee Channels. Where a slough wall is required at the toe of the slope or a retaining wall is built to support any cut or fill, a vee channel shall be constructed behind the wall to carry off the slope waters.

6. Inlet Structures, Downdrains and Outlet Structures.

a. Inlet Structures. Inlet structures shall be of concrete or galvanized steel hot-dipped in asphalt or equivalent. The inlet shall be grated or of such entry shape as to prevent entry of objects of greater than four inches in dimension. Wet structures shall be placed as shown in the city standard construction details and shall be so shaped as to minimize entry losses. An overflow structure into the vee downdrains shall be provided.

b. Downdrains. Pipe downdrains shall be corrugated steel pipe, galvanized, hot dipped in asphalt or equivalent with paved invert or reinforced concrete pipe, D-800 or PVC SDR 35 or HDPE in conformance with the city standard construction details, and shall have a diameter of a size required by runoff calculations, but not less than 12 inches.

Open downdrains shall be of concrete or corrugated galvanized steel hot-dipped in asphalt or its equivalent with paved invert. Open channel downdrains shall be designed by a civil engineer and shall have a minimum capacity equal to four times the required pipe size. The alignment of downdrains shall be such as to conserve velocity head.

c. Outlet Structures. Outlet structures shall be of concrete or as approved by the city engineer.

Where outletting into streets, the structure shall be of a design approved by the city engineer.

Where outletting into natural watercourses or other approved locations, the structure shall be provided with adequate velocity reducers, diversion walls, rip-rap, concrete aprons or similar energy dissipator as approved by the city engineer or other jurisdictional agency. All slope drainage shall be collected and disposed of in the drainage device.

7. Runoff Computations. Runoff shall be based upon the proper 50-year isohyetal and the runoff calculation shall be based upon the latest methods approved by the city engineer.

8. Drainage Dispersal Wall. A drainage dispersal wall shall be constructed in conformance with the city standard construction details whenever it is necessary to convert channel flow to sheet flow.

9. Site Drainage. All building pads shall slope a minimum of two percent to an approved drainage device or to a public street. Where used, the drainage device shall be an adequately designed system of catch basins and drain lines which conducts the water to a street, storm drain or natural watercourse approved by the city engineer, as a safe place to deposit such waters. Refer to city’s building standards for fine grading requirements and drainage around building foundations (Chapter 12.115).

10. Maintenance of Drainage. Drainage in conformance with the provisions of this division shall be maintained during and subsequent to construction. Suitable access shall be provided to permit cleaning and maintenance of all drainage and erosion control devices.

K. Driveway Slopes. Driveways shall have a maximum slope of 5:1 (20 percent) and shall terminate at both ends with vertical curves. The vertical curve of the bottom of the driveway slope shall have a minimum length of five feet. The vertical curve at the top of the driveway slope shall have a minimum length of 10 feet. Vertical curves at grade changes, which exceed one-half percent, shall have a minimum length of five feet. (Ord. No. 2017-009, § 1, 5-22-17)

A. Building Setback. Building foundations shall be located clear of all slopes in accordance with the California Building Code (CBC) as adopted by the city of San Buenaventura. (Ord. No. 2017-009, § 1, 5-22-17)

A. General. A buttress fill is a designed compacted earth fill used for providing lateral support to an unstabilized soil mass. All buttress fills shall comply with the most restrictive of the requirements of this section or other sections of this division.

B. Foundation. The ability of the foundation soil to support the buttress shall be investigated and a soils engineer shall provide specifications for keying of the base of the buttress and for bonding the buttress to the natural ground.

C. Base Width. The minimum base width of a buttress fill shall not be less than 15 feet. The width of a buttress fill may vary uniformly to a top width of not less than 12 feet.

D. Height. The maximum height of buttress fill shall be 30 feet unless the geotechnical engineer provides substantiating calculations to justify a height greater than 30 feet.

E. Slope. The exposed surface of a buttress fill shall not exceed a slope of 2:1.

Exception: The city engineer may permit a buttress fill to be made which creates an exposed surface steeper in slope than 2:1 provided:

1. The use of the steeper slope is determined to be necessary due to special design limitations on the site; and

2. The gradient does not exceed one and one-half horizontal to one vertical; and

3. The applicant shows through investigation, subsurface exploration, analyses and report by both a qualified geotechnical engineer and an engineering geologist, to the city engineer’s satisfaction, that the buttress fill to be used and the underlying bedrock supporting the fill will have strength characteristics sufficient to produce a stable slope with a minimum factor of safety not less than one and one-half under static loads.

F. Subdrain. Subdrains which blanket the entire back face of the buttress or which occur at intervals shall be provided to prevent buildup of hydrostatic pressure. Details of subdrains shall be provided by the geotechnical engineer.

G. Design. Design calculations for all buttress fills shall be prepared by a civil engineer or geotechnical engineer and submitted to the city engineer.

For design purposes, the resistance of the bedding plane shall be substantiated by tests taken along the probable slip plane under conditions simulating the worst possible field conditions. The method of performing these tests shall be included in the geotechnical engineer’s reports.

The mass of earth to be retained shall be assumed to extend a minimum distance from the top face edge of the buttress equal to (1) the vertical height of the buttress when the surface slope above does not exceed six degrees, or (2) 100 feet when the surface slope above the buttress exceeds six degrees.

The type, percentage of compaction, cohesion and angle of internal friction of the materials to be placed in the buttress shall be specified. The buttress fill shall be designed for a minimum safety factor of one and one-half, based upon the smaller value of ultimate or residual shear strength of the fill material.

H. Deviations. Upon recommendation by a geotechnical engineer, deviations from the above requirements other than those set forth in subsection E of this section may be approved if the city engineer determines that the proposed deviations do not endanger life, limb, health, property, safety, or public welfare. (Ord. No. 2017-009, § 1, 5-22-17)

A. General. The provisions of this section shall be fully complied with prior to issuance of a grading permit in areas subject to existing or potential slides, unstable soil, or geologic hazards or other hazardous conditions as determined by the city engineer.

B. Records and Maps. The city engineer or building official may adopt maps delineating areas of relative hazard for the application of this section.

C. Permission to Do Work.

1. Active Landslide and Historic Landslide Areas. No building or grading permits shall be issued for development in active or historic landslide areas until, and unless, stabilization of the entire slide or soil mass which may have an adverse effect on the proposed development or access thereto can be satisfactorily demonstrated to the city engineer and the building official.

2. Prehistoric Landslide or Questionable Areas. No building or grading permit shall be issued for development in prehistoric landslide or questionable areas except by specific approval of the city engineer and the building official, based upon a geological report by an approved soils engineer or geologist, attesting to the apparent safety of the proposed developments, and stating that the development is not located in an area subject to slides or unstable soil which may have an adverse effect on the proposed development or access thereto.

3. Geologically Hazardous Areas.

a. An engineering geology report by a geotechnical engineer or engineering geologist shall be submitted to the city engineer for approval for all grading or construction sites which meet the following criteria:

i. All projects which require a soils, geotechnical, or geological report under other sections of this division.

ii. All projects which are within the boundaries of special study areas, seismic zones, geohazard zones, or moderate or high liquefaction hazard zones.

Exclusions: Single-story additions to single-family residences may be excluded from these requirements if the city engineer or the building official determines that such exemption would not endanger life, limb, health, property, safety or public welfare.

b. Where the engineering geology report determines that there is a significant potential geological hazard, mitigation measures as recommended in the report and approved by the city engineer shall be performed.

4. Other Conditions. If, in the opinion of the city engineer or the building official, there is evidence of potentially hazardous conditions other than those covered by subsections (C)(1), (C)(2), and (C)(3) of this section, satisfactory reports from an approved soils engineer and engineering geologist may be required. If such reports are required, a permit may be issued if the reports testify to the apparent safety of the development. If, in the opinion of the city engineer or building official, it is found that the area in question has elements of hazard, or if the reports so indicate, a permit may be refused. (Ord. No. 2017-009, § 1, 5-22-17)

A. General. All grading plans and permits and the owner of any property on which such grading is performed shall comply with the provisions of this section for NPDES compliance.

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

B. Stormwater Pollution Prevention Plan (SWPPP). The city engineer may require a SWPPP in accordance with the Ventura County stormwater quality NPDES MS4 permit. The SWPPP shall contain details of best management practices (BMPs), including 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. No grading permit shall be issued until a written notice of intent has been obtained by the permittee from the State Regional Water Quality Control Board and the SWPPP has been completed by the permittee’s engineer and is ready to be available at the construction site at all times. Upon inspection by and at the direction of city, the grading permit applicant shall make corrections to the SWPPP if the BMPs are not functioning properly. The city engineer may issue a stop work order on all grading until the site is brought into NPDES compliance.

C. Stormwater Pollution Control Plan (SWPCP). A SWPCP may be required on projects that are less than one acre of disturbed area. The SWPCP shall contain practical best management practices (BMPs) to reduce the discharge of construction pollutants and sedimentation to a water body. A SWPCP shall be signed by the grading permit applicant and project engineer. The SWPCP will remain in effect throughout the duration of the grading permit. The SWPCP may need to be revised during construction to reflect the current site conditions. Upon inspection by and at the direction of city, the grading permit applicant shall make corrections to the SWPCP if the BMPs are not functioning properly. The city engineer may issue a stop work order on all grading until the site is brought into NPDES compliance.

D. SWPPP and SWPCP, Effect of Noncompliance. Should the owner fail to install the best management practices (BMPs) required by this section, it shall be deemed that a default has occurred under the conditions of the grading permit security. The city engineer may deem it necessary to protect adjoining property from the effects of erosion, flooding or the deposition of mud, debris or construction-related pollutants and require the surety to install and maintain adequate sediment control BMPs and protect the adjacent properties and watercourses that may be threatened from sedimentation. (Ord. No. 2017-009, § 1, 5-22-17)