Belvedere Municipal Code Ch. 16.15 Grading and Erosion Control

Sections:

• 16.15.010 Purpose and intent. 16.15.020 Findings. 16.15.030 Authority. 16.15.040 Exemptions. 16.15.051 Adverse soil conditions—Recordation of notice. 16.15.052 Site map and grading plan. 16.15.053 Soils engineering (soils and engineering geology report). 16.15.054 Foundation design. 16.15.055 Work schedule. 16.15.056 Security. 16.15.060 Erosion control plans—Required submittals. 16.15.065 Inspection. 16.15.070 Modifications. 16.15.080 Rainy season grading. 16.15.090 Permit denial, revocation or suspension.

A. The purpose of this Chapter is to establish controls on the earthwork permitted by the City in the course of construction. The controls are established for reasons of aesthetics, sound soil engineering practice, erosion control, and water quality protection

B. It is the intent of the City to limit grading operations whenever possible. Grading necessary to construct structures should be confined within the footprint of the structure. Applicants for grading permits will be encouraged to construct retaining walls if it is apparent that graded cut and fill banks cannot be integrated into the natural surroundings in an acceptable manner. Exposed banks will be landscaped rather than merely seeded for erosion control.

C. Nothing within this Chapter shall void the provisions of Chapter 70 of the Uniform Building Code, adopted by the City pursuant to Section 16.04.010 of this Title. (Ord. 89-1 § 2, 1989.)

The City Council finds that the adoption of the ordinance codified in this Chapter is made necessary for the following reasons:

A. The topography in Belvedere is characterized by densely wooded hillsides. Inadequately controlled grading will result in permanent scarring and excessive erosion.

B. Also a characteristic of Belvedere is the high amount of rainfall and excessive runoff. These features, combined with inadequately controlled grading, can increase the possibility of earth slides and poor water quality from excessive erosion. (Ord. 89-1 § 2, 1989.)

The authority of promulgating administrative procedures and standards is based in the Uniform Building Code, Chapter 70, Excavation and Grading. All activities subject to the City’s subdivision map requirements and/or building permit shall meet the standards set forth in this Section. These provisions are adopted in addition to, and not as a substitute for, current grading regulations. (Ord. 89-1 § 2, 1989.)

Activities within the scope of this Chapter may be exempted from the standards if the Public Works Director determines that the activities do not pose a significant erosion problem, and they meet all of the following conditions:

• A. The area to be graded or filled does not exceed one thousand square feet;

• B. Volume of material to be graded or filled does not exceed two hundred cubic yards;

• C. Volume of soil or other earthen material to be stockpiled does not exceed fifty cubic yards;

• D. Natural and finished slopes are less than ten percent;

• E. The earthwork does not occur within one hundred feet of a natural or manmade watercourse or body of water;

• F. Excavations are for footings, piers, or utilities only;

• G. Exploratory excavations are prepared under direction of soils engineers or engineering geologists. (Ord. 89-1 § 2, 1989.)

When application is made to any department or agency of the City for an entitlement to improve or develop any real property in an area of suspected soils instability, the City may require that the applicant submit a report of soil investigation prepared by a registered civil engineer specializing and recognized in soil mechanics and foundation engineering or a geologist whose qualifications are satisfactory to the City. If the report discloses adverse soils conditions, the City may require that as a condition to the issuance of an entitlement to improve or develop real property, there shall be recorded in the office of the county recorder a “notice of adverse soils conditions” in a form satisfactory to the City. (Ord. 89-1 § 2, 1989.)

A site map and grading plan shall be required for all applications for the construction of new residences, subdivisions, or the construction of any structure or addition to a structure exceeding one thousand square feet in area, or on slopes exceeding forty percent or in any area identified in the general plan of the City as being subject to soil or slope instability. Said map and plan shall be prepared by any professional licensed to prepare surveys, and shall be based upon an accurate topographic survey. The site map and grading plan shall contain all of the following information

A. Existing and proposed topography of the site taken at a contour interval sufficiently detailed to define the topography and the drainage pattern over the entire site. Ninety percent of the contours shall be plotted within one contour interval of the true location;

B. Two contour intervals that extend a minimum of one hundred feet off-site (or sufficient to show on- and offsite drainage);

C. Location and graphic representation of all existing and proposed natural and man-made drainage facilities, trees (showing size and species), structures and paved areas, and utilities;

D. Detailed plans of all surface and subsurface drainage devices, walls, cribbing, dikes, and other protective devices to be constructed with, or as part of the proposed work, together with a map showing the drainage area and the estimated runoff of the area served by any drain;

E. Location and graphic representation of proposed excavations and fills, on-site storage of soil and other earthen material, and on-site disposal;

• F. Location of proposed temporary and final surface runoff, erosion and sediment control measures;

• G. Quantity of soil and earthen materials in cubic yards to be excavated, filled, stored or otherwise utilized on site;

H. Proposed sequence and schedule of excavation, filling and other land-disturbing and filling activities, and soils or earthen material storage and disposal. (Ord. 89-1 § 2, 1989.)

A soils and engineering geology report, prepared by a licensed geotechnical engineer, shall be required for all construction for which a site map and grading plan is required under Section 16.15.052 above, unless specifically waived by the director of public works. A soils and engineering geology report shall be based on adequate and necessary test borings, and shall contain all the following information:

• A. Data regarding the nature, particle size, distribution, location, strength and erodibility of existing soils;

• B. Data regarding the nature, distribution, strength and erodibility of soils to be placed on the site, if any;

• C. Conclusions and recommendations for grading procedures;

• D. Conclusions and recommended designs for interim soil stabilization devices and measures and for permanent soils stabilization after construction is completed;

• E. Design criteria for corrective measures when necessary;

• F. Opinions and recommendations covering adequacy of site to be developed by the proposed grading;

• G. An adequate description of the geology of the site;

• H. Conclusions and recommendations regarding the effect of geologic conditions on the proposed development;

• I. Opinions and recommendations included in the report and approved by the director or the building inspector shall be incorporated into the grading plans or specifications. (Ord. 89-1 § 2, 1989.)

All new and substantially altered foundations must be designed by a licensed foundation designer, with such design based upon the recommendations and opinions of the soils and engineering geology report required in Section 16.15.053 above. (Ord. 89-1 § 2, 1989.)

The applicant must submit a master work schedule showing the following information

• A. Proposed grading schedule;

• B. Schedule for construction of final improvements, if any;

• C. Schedule for installation of temporary and permanent erosion and sediment control devices where required;

• D. Schedule for maintenance of temporary and permanent erosion and sediment control measures. (Ord. 89-1

• § 2, 1989.)

Where major grading is approved subject to the provisions of this Chapter, security for the performance of the work shall be provided as required in the City’s subdivision map ordinance, and the State of California Subdivision Map Act, in an amount and form acceptable to the City engineer and director of public works. (Ord. 89-1 § 2, 1989.)

• A. Temporary Erosion Control Plans.

  1. When determined by the director of public works, the applicant shall submit plans for temporary erosion control for approval. Temporary erosion control plans for the construction period must be equal to, or more effective than, the equivalent best management practices adopted by the Public Works Director.

  2. Temporary erosion control plans will be required when any of the following conditions exist:

     • a. There is a probability that runoff from graded areas cannot be contained on the subject property;

     • b. There is a major watercourse which will be adversely affected by runoff from the graded area.

  3. Temporary erosion control plans shall be substituted and approved at the time the grading or building permit is obtained.

  4. The applicant shall be responsible for maintaining temporary erosion control measures to the satisfaction of the Public Works Director at all times. To guarantee conformance to requirements, the director of public works may require appropriate bonding and/or cash deposits.

• B. Permanent Erosion Control Plans.

  1. Each grading plan submitted to the City for approval must include provisions for permanent erosion control. Erosion control techniques proposed for the post-construction period must be equal to or more effective than the equivalent best management practices adopted by the Public Works Director.

2. Plans shall include detailed design and installation specifications for both temporary and permanent erosion and sediment control measures. Supporting calculations, including runoff calculations, shall also be submitted. To insure compliance with the approved plans, the director of public works may require appropriate bonding and/or cash deposits.

• C. Guidelines for Information to be Submitted. In addition to or supplementing the information requested above, the applicant shall provide the following:

  1. A narrative description of the proposed work and erosion problem areas;

  2. Descriptions and design specifications for all forms of erosion and sediment control measures which may include sediment retention basins, surface runoff and vegetative measures;

  3. A cost estimate for implementing and maintaining all of the above. (Ord. 89-1 § 2, 1989.)

The director may require the applicant to obtain a registered civil engineer to inspect any portion of work undertaken on a project who would then report the results of the inspection to the City, certifying compliance with the grading or erosion control plans and specifications. (Ord. 89-1 § 2, 1989.)

The Public Works Director may require modification of previously approved plans to accommodate unanticipated conditions on the site. Modifications to a previously approved plan may also be required, if the plan is found to be inadequate, or work does not proceed as scheduled. The Public Works Director may require the permittee to submit work schedules, contingency plans, or status reports as deemed necessary. The Public Works Director shall notify permittee in writing of the requirements and specify a reasonable time period for compliance. (Ord. 89-1 § 2, 1989.)

A. Special authorization must be received from the director of public works prior to any grading activity during the rainy season (October 15th to April 15th). If there appears to be a likelihood of unavoidable damage from rainy season grading, the Public Works Director may refuse to issue a permit, may revoke a permit already issued, or temporarily suspend grading operations

B. Regardless of whether grading is or is not permitted during the period from October 15th to April 15th, all temporary and permanent erosion control measures shall be in place prior to October 15th. (Ord. 89-1 § 2, 1989.)

A. The applicant may request a hearing before the Planning Commission within five work days of notification of a permit denial, revocation or suspension. The hearing shall be held at the next regularly scheduled Planning Commission meeting following the date of the request for a hearing. Grounds for revoking or suspending a permit include failure to follow approved plans, failure to follow any conditions attached to the permit, failure to implement provision in timely fashion, and failure to properly maintain erosion control features

B. The Public Works Director shall have the authority to order immediate cessation of all grading or improvement work and, further, to order immediate correction and/or installation of any or all erosion control measures described in this Chapter. The Public Works Director may use the security provided by the permittee in order to finance corrective measures if the permittee is unwilling to do so as ordered by the Public Works Director. (Ord. 89-1 § 2, 1989.)