Article 3 — General Provisions

This Chapter shall apply to all areas of special flood hazards within the jurisdiction of City of Hercules, Contra Costa County.

(Formerly 10-7.201; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

The areas of special flood hazard identified by the Federal Emergency Management Agency (FEMA) in the "Flood Insurance Study (FIS) for City of Hercules, Contra Costa County" dated March 30, 1982, with accompanying Flood Insurance Rate Maps (FIRMs) and Flood Boundary and Floodway Maps (FBFMs), dated September 30, 1982, and all subsequent amendments and/ or revisions, are hereby adopted by reference and declared to be a part of this Chapter. This FIS and attendant mapping is the minimum area of applicability of this Chapter and may be supplemented by studies for other areas which allow implementation of this Chapter and which are recommended to the City of Hercules City Council by the Floodplain Administrator. The study, FIRMs and FBFMs are on file at City of Hercules, 111 Civic Drive, Hercules, CA 94547. (Formerly 10-7.202; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

No structure or land shall hereafter be constructed, located, extended, converted, or altered without full compliance with the terms of this Chapter and other applicable regulations. Violation of the requirements (including violations of conditions and safeguards) shall constitute a misdemeanor. Nothing herein shall prevent the City of Hercules City Council from taking such lawful action as is necessary to prevent or remedy any violation.

(Formerly 10-7.203; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

This Chapter is not intended to repeal, abrogate, or impair any existing easements, covenants, or deed restrictions. However, where this Chapter and another ordinance, easement, covenant, or deed restriction conflict or overlap, whichever imposes the more stringent restrictions shall prevail.

(Formerly 10-7.204; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

In the interpretation and application of this Chapter, all provisions shall be:

• (a) Considered as minimum requirements; and

• (b) Liberally construed in favor of the governing body; and

• (c) Deemed neither to limit nor repeal any other powers granted under state statutes. (Formerly 10-7.205; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

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City of Hercules, CA

Sec. 10-7.306

HERCULES CODE

Sec. 10-7.307

The degree of flood protection required by this Chapter is considered reasonable for regulatory purposes and is based on scientific and engineering considerations. Larger floods can and will occur on rare occasions. Flood heights may be increased by manmade or natural causes. This Chapter does not imply that land outside the areas of special flood hazards or uses permitted within such areas will be free from flooding or flood damages. This Chapter shall not create liability on the part of City of Hercules City Council, any officer or employee thereof, the State of California, or the Federal Emergency Management Agency, for any flood damages that result from reliance on this Chapter or any administrative decision lawfully made hereunder. (Formerly 10-7.206; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

This Chapter and the various parts thereof are hereby declared to be severable. Should any section of this Chapter be declared by the courts to be unconstitutional or invalid, such decision shall not affect the validity of this Chapter as a whole, or any portion thereof other than the section so declared to be unconstitutional or invalid. (Ord. 449 § 1 (part), 2009)

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City of Hercules, CA

Sec. 10-7.401

LAND USE

Sec. 10-7.402

Article 4 Administration

The Director of Public Works is hereby appointed to administer, implement, and enforce this Chapter by granting or denying development permits in accord with its provisions. (Formerly 10-7.302; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

The duties and responsibilities of the Floodplain Administrator shall include, but not be limited to, the following:

• (a) Permit Review. Review all development permits to determine:

  • (1) Permit requirements of this Chapter have been satisfied, including determination of substantial improvement and substantial damage of existing structures; and

  • (2) All other required state and federal permits have been obtained; and

  • (3) The site is reasonably safe from flooding; and

  • (4) The proposed development does not adversely affect the carrying capacity of areas where base flood elevations have been determined but a floodway has not been designated. This means that the cumulative effect of the proposed development when combined with all other existing and anticipated development will not increase the water surface elevation of the base flood more than one (1) foot at any point within the City of Hercules, Contra Costa County; and

  • (5) All Letters of Map Revision (LOMRs) for flood control projects are approved prior to the issuance of building permits. Building permits must not be issued based on Conditional Letters of Map Revision (CLOMRs). Approved CLOMRs allow construction of the proposed flood control project and land preparation as specified in the "start of construction" definition.

• (b) Development of Substantial Improvement and Substantial Damage Procedures.

  • (1) Using FEMA publication FEMA 213, "Answers to Questions about Substantially Damaged Buildings," develop detailed procedures for identifying and administering requirements for substantial improvement and substantial damage, to include defining "market value."

  • (2) Assure procedures are coordinated with other departments/divisions and implemented by community staff.

• (c) Review, Use and Development of Other Base Flood Data. When base flood elevation data has not been provided in accordance with Section 10-7.302, the Floodplain Administrator shall obtain, review, and reasonably utilize any base flood elevation and floodway data available from a federal or state agency, or other source, in order to administer Article 5 of this Chapter.

NOTE: A base flood elevation may be obtained using one (1) of two (2) methods from

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City of Hercules, CA

Sec. 10-7.402

HERCULES CODE

Sec. 10-7.402

the FEMA publication, FEMA 265, "Managing Floodplain Development in Approximate Zone A Areas—A Guide for Obtaining and Developing Base (100-year) Flood Elevations," dated July 1995.

• (d) Notification of Other Agencies.

  • (1) Alteration or Relocation of a Watercourse.

    • A. Notify adjacent communities and the California Department of Water Resources prior to alteration or relocation; and

    • B. Submit evidence of such notification to the Federal Emergency Management Agency; and

    • C. Assure that the flood-carrying capacity within the altered or relocated portion of said watercourse is maintained.

  • (2) Base Flood Elevation Changes Due to Physical Alterations.

• A. Within six (6) months of information becoming available or project completion, whichever comes first, the Floodplain Administrator shall submit or assure that the permit applicant submits technical or scientific data to FEMA for a Letter of Map Revision (LOMR).

  - B. All LOMRs for flood control projects are approved prior to the issuance of building permits. Building permits must not be issued based on Conditional Letters of Map Revision (CLOMRs). Approved CLOMRs allow construction of the proposed flood control project and land preparation as specified in the "start of construction" definition.
  

Such submissions are necessary so that upon confirmation of those physical changes affecting flooding conditions, risk premium rates and floodplain management requirements are based on current data.

• (3) Changes in Corporate Boundaries. Notify FEMA in writing whenever the corporate boundaries have been modified by annexation or other means and include a copy of a map of the community clearly delineating the new corporate limits.

• (e) Documentation of Floodplain Development. Obtain and maintain for public inspection and make available as needed the following:

  • (1) Certification required by Sections 10-7.501(c)(1) and 10-7.504 (lowest floor elevations); and

  • (2) Certification required by Section 10-7.501(c)(2) (elevation or floodproofing of nonresidential structures); and

  • (3) Certification required by Section 10-7.501(c)(3) (wet floodproofing standard); and

  • (4) Certification of elevation required by Section 10-7.503(a)(3) (subdivisions and other proposed development standards); and

  • (5) Certification required by Section 10-7.506(b) (floodway encroachments); and

  • (6) Information required by Section 10-7.507(f) (coastal construction standards); and

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City of Hercules, CA

Sec. 10-7.402

LAND USE

Sec. 10-7.403

• (7) Maintain a record of all variance actions, including justification for their issuance, and report such variances issued in its biennial report submitted to the Federal Emergency Management Agency.

• (f) Map Determination. Make interpretations where needed, as to the exact location of the boundaries of the areas of special flood hazard, where there appears to be a conflict between a mapped boundary and actual field conditions. The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in Section 10-7.404.

• (g) Remedial Action. Take action to remedy violations of this Chapter as specified in Section 10-7.303.

• (h) Biennial Report. Complete and submit biennial report to FEMA.

• (i) Planning. Assure community's General Plan is consistent with floodplain management objectives herein.

• (Formerly 10-7.303; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

A development permit shall be obtained before any construction or other development, including manufactured homes, within any area of special flood hazard established in Section 10-7.302. Application for a development permit shall be made on forms furnished by the City of Hercules. The applicant shall provide the following minimum information:

• (a) Plans in duplicate, drawn to scale, showing:

  • (1) Location, dimensions, and elevation of the area in question, existing or proposed structures, storage of materials and equipment and their location; and

  • (2) Proposed locations of water supply, sanitary sewer, and other utilities; and

  • (3) Grading information showing existing and proposed contours, any proposed fill, and drainage facilities; and

  • (4) Location of the regulatory floodway when applicable; and

  • (5) Base flood elevation information as specified in Section 10-7.302 or 10-7.402(c); and

  • (6) Proposed elevation in relation to mean sea level of the lowest floor (including basement) of all structures; and

  • (7) Proposed elevation in relation to mean sea level to which any nonresidential structure will be floodproofed, as required in Section 10-7.501(c)(2) and detailed in FEMA Technical Bulletin TB 3-93; and

  • (8) Certification from a registered civil engineer or architect that the nonresidential floodproofed building meets the floodproofing criteria in Section 10-7.501(c)(2); and

  • (9) For a crawl-space foundation, location and total net area of foundation openings as required in Article 5, Section 10-7.501(c)(3) of this Chapter and detailed in FEMA Technical Bulletins 1-93 and 7-93; and

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City of Hercules, CA

Sec. 10-7.403

HERCULES CODE

Sec. 10-7.404

• (10) Description of the extent to which any watercourse will be altered or relocated as a result of proposed development.

• (b) All appropriate certifications listed in Section 10-7.402(e).

(Formerly 10-7.301; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

The City of Hercules City Council of City of Hercules, Contra Costa County shall hear and decide appeals when it is alleged there is an error in any requirement, decision, or determination made by the Floodplain Administrator in the enforcement or administration of this Chapter. (Ord. 449 § 1 (part), 2009)

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City of Hercules, CA

Sec. 10-7.501

LAND USE

Sec. 10-7.501

Subarticle 5 Provisions For Flood Hazard Reduction

In all areas of special flood hazards the following standards are required:

• (a) Anchoring. All new construction and substantial improvements of structures, including manufactured homes, shall be adequately anchored to prevent flotation, collapse or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.

• (b) Construction Materials and Methods. All new construction and substantial improvements of structures, including manufactured homes, shall be constructed:

  • (1) With flood-resistant materials, and utility equipment resistant to flood damage for areas below the base flood elevation;

  • (2) Using methods and practices that minimize flood damage;

  • (3) With electrical, heating, ventilation, plumbing and air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding; and

  • (4) Within Zones AH or AO, so that there are adequate drainage paths around structures on slopes to guide flood waters around and away from proposed structures.

• (c) Elevation and Floodproofing.

  • (1) Residential Construction. All new construction or substantial improvements of residential structures shall have the lowest floor, including basement:

    • A. In AE, AH, A1—30 Zones, elevated to or above the base flood elevation.

    • B. In an AO zone, elevated above the highest adjacent grade to a height equal to or exceeding the depth number specified in feet on the FIRM, or elevated at least two (2) feet above the highest adjacent grade if no depth number is specified.

    • C. In an A zone, without BFEs specified on the FIRM (unnumbered A Zone), elevated to or above the base flood elevation; as determined under Section 10-7.402(c).

Upon the completion of the structure, the elevation of the lowest floor, including basement, shall be certified by a registered civil engineer or licensed land surveyor, and verified by the Community Building Inspector to be properly elevated. Such certification and verification shall be provided to the Floodplain Administrator.

• (2) Nonresidential Construction. All new construction or substantial improvements of nonresidential structures shall either be elevated to conform to subsection (c)(1) of this Section or:

  • A. Be floodproofed, together with attendant utility and sanitary facilities, below the elevation recommended under subsection (c)(1) of this Section, so that the structure is watertight with walls substantially impermeable to the passage of water; and

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City of Hercules, CA Sec. 10-7.501

HERCULES CODE

Sec. 10-7.501

• B. Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and

• C. Be certified by a registered civil engineer or architect that the standards of subsection (c)(2)(A) and (B) of this Section are satisfied. Such certification shall be provided to the Floodplain Administrator.

• (3) Flood Openings. All new construction and substantial improvements of structures with fully enclosed areas below the lowest floor (excluding basements) that are usable solely for parking of vehicles, building access or storage, and which are subject to flooding, shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwater. Designs for meeting this requirement must meet the following minimum criteria:

  • A. For nonengineered openings:

    • i. Have a minimum of two (2) openings on different sides having a total net area of not less than one (1) square inch for every square foot of enclosed area subject to flooding; and

    • ii. The bottom of all openings shall be no higher than one (1) foot above grade; and

    • iii. Openings may be equipped with screens, louvers, valves or other coverings or devices; provided, that they permit the automatic entry and exit of floodwater; and

    • iv. Buildings with more than one (1) enclosed area must have openings on exterior walls for each area to allow flood water to directly enter; or

  • B. Be certified by a registered civil engineer or architect.

• (4) Manufactured homes. See Section 10-7.504.

• (5) Garages and Low-Cost Accessory Structures.

  • A. Attached Garages.

    • i. A garage attached to a residential structure, constructed with the garage floor slab below the BFE, must be designed to allow for the automatic entry of flood waters. See subsection (c)(3) of this Section. Areas of the garage below the BFE must be constructed with flood resistant materials. See subsection (b) of this Section.

    • ii. A garage attached to a nonresidential structure must meet the above requirements or be dry floodproofed. For guidance on below grade parking areas, see FEMA Technical Bulletin TB-6.

  • B. Detached Garages and Accessory Structures.

    • i. "Accessory structures" used solely for parking (two (2) car detached garages or smaller) or limited storage (small, low-cost sheds), as defined in Article 2 of this Chapter, may be constructed such that its floor is below the base flood elevation (BFE), provided the structure is designed and

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City of Hercules, CA

Sec. 10-7.501

LAND USE

Sec. 10-7.503

constructed in accordance with the following requirements:

• a. Use of the accessory structure must be limited to parking or limited storage; and

• b. The portions of the accessory structure located below the BFE must be built using flood-resistant materials; and

• c. The accessory structure must be adequately anchored to prevent flotation, collapse and lateral movement; and

• d. Any mechanical and utility equipment in the accessory structure must be elevated or floodproofed to or above the BFE; and

• e. The accessory structure must comply with floodplain encroachment provisions in Section 10-7.506; and

• f. The accessory structure must be designed to allow for the automatic entry of flood waters in accordance with subsection (c)(3) of this Section.

• ii. Detached garages and accessory structures not meeting the above standards must be constructed in accordance with all applicable standards in this Section.

(Formerly 10-7.401; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

• (a) All new and replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate:

  • (1) Infiltration of flood waters into the systems; and

  • (2) Discharge from the systems into flood waters.

• (b) On-site waste disposal systems shall be located to avoid impairment to them, or contamination from them during flooding.

(Formerly 10-7.402; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

• (a) All new subdivision proposals and other proposed development, including proposals for manufactured home parks and subdivisions, greater than fifty (50) lots or five (5) acres, whichever is the lesser, shall:

  • (1) Identify the Special Flood Hazard Areas (SFHA) and Base Flood Elevations (BFE).

  • (2) Identify the elevations of lowest floors of all proposed structures and pads on the final plans.

  • (3) If the site is filled above the base flood elevation, the following as-built information for each structure shall be certified by a registered civil engineer or licensed land surveyor and provided as part of an application for a Letter of Map Revision based on Fill (LOMR-F) to the Floodplain Administrator:

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City of Hercules, CA

Sec. 10-7.503

HERCULES CODE

Sec. 10-7.505

• A. Lowest floor elevation.

• B. Pad elevation.

• C. Lowest adjacent grade.

• (b) All subdivision proposals and other proposed development shall be consistent with the need to minimize flood damage.

• (c) All subdivision proposals and other proposed development shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.

• (d) All subdivisions and other proposed development shall provide adequate drainage to reduce exposure to flood hazards.

• (Formerly 10-7.403; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

• (a) All manufactured homes that are placed or substantially improved, on sites located: (1) outside of a manufactured home park or subdivision; (2) in a new manufactured home park or subdivision; (3) in an expansion to an existing manufactured home park or subdivision; or (4) in an existing manufactured home park or subdivision upon which a manufactured home has incurred "substantial damage" as the result of a flood, shall:

  • (1) Within Zones A1—30, AH, and AE on the community's Flood Insurance Rate Map, be elevated on a permanent foundation such that the lowest floor of the manufactured home is elevated to or above the base flood elevation and be securely fastened to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.

  • (2) Within Zones V1—30, V, and VE on the community's Flood Insurance Rate Map, meets the requirements of Section 10-7.507.

• (b) All manufactured homes to be placed or substantially improved on sites in an existing manufactured home park or subdivision within Zones A1—30, AH, AE, V1—30, V, and VE on the community's Flood Insurance Rate Map that are not subject to the provisions of subsection (a) of this Section will be securely fastened to an adequately anchored foundation system to resist flotation, collapse, and lateral movement, and be elevated so that either the:

  • (1) Lowest floor of the manufactured home is at or above the base flood elevation; or

  • (2) Manufactured home chassis is supported by reinforced piers or other foundation elements of at least equivalent strength that are no less than thirty-six (36) inches in height above grade.

Upon the completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered civil engineer or licensed land surveyor, and verified by the Community Building Inspector to be properly elevated. Such certification and verification shall be provided to the Floodplain Administrator.

(Formerly 10-7.404; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

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City of Hercules, CA

Sec. 10-7.505

LAND USE

Sec. 10-7.507

• (a) All recreational vehicles placed in Zones A1—30, AH, AE, V1—30 and VE will either:

  • (1) Be on the site for fewer than one hundred eighty (180) consecutive days; or

  • (2) Be fully licensed and ready for highway use. A recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached additions; or

  • (3) Meet the permit requirements of Section 10-7.403 and the elevation and anchoring requirements for manufactured homes in Section 10-7.504.

• (b) Recreational vehicles placed on sites within Zones V1—30, V, and VE on the community's Flood Insurance Rate Map will meet the requirements of subsection (a) of this Section and Section 10-7.507.

• (Ord. 449 § 1 (part), 2009)

Since floodways are an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles, and erosion potential, the following provisions apply:

• (a) Until a regulatory floodway is adopted, no new construction, substantial development, or other development (including fill) shall be permitted within Zones A1—30 and AE, unless it is demonstrated that the cumulative effect of the proposed development, when combined with all other development, will not increase the water surface elevation of the base flood more than one (1) foot at any point within the City of Hercules, Contra Costa County.

• (b) Within an adopted regulatory floodway, the City of Hercules, Contra Costa County, shall prohibit encroachments, including fill, new construction, substantial improvements, and other development, unless certification by a registered civil engineer is provided demonstrating that the proposed encroachment shall not result in any increase in flood levels during the occurrence of the base flood discharge.

• (c) If Sections 10-7.501(a) and (b) and 10-7.602(a) and (b) are satisfied, all new construction, substantial improvement, and other proposed new development shall comply with all other applicable flood hazard reduction provisions of Article 5 of this chapter.

• (Formerly 10-7.405; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

Within coastal high hazard areas, Zones V, V1—30, and VE, as established under Section 10-7.302, the following standards shall apply:

• (a) All new residential and nonresidential construction, including substantial improvement/ damage, shall be elevated on adequately anchored pilings or columns and securely anchored to such pilings or columns so that the bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) is elevated to or above the base flood level. The pile or column foundation and structure attached thereto is anchored to resist flotation, collapse, and lateral movement due to the effects of wind and water loads acting simultaneously on all building components. Water loading values used shall be those associated with the base flood. Wind loading values used shall be those required by

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City of Hercules, CA Sec. 10-7.507

HERCULES CODE

Sec. 10-7.507

applicable state or local building standards.

• (b) All new construction and other development shall be located on the landward side of the reach of mean high tide.

• (c) All new construction and substantial improvement shall have the space below the lowest floor free of obstructions or constructed with breakaway walls as defined in Article 2 of this Chapter. Such enclosed space shall not be used for human habitation and will be usable solely for parking of vehicles, building access or storage.

• (d) Fill shall not be used for structural support of buildings.

• (e) Manmade alteration of sand dunes which would increase potential flood damage is prohibited.

• (f) The Floodplain Administrator shall obtain and maintain the following records:

  • (1) Certification by a registered engineer or architect that a proposed structure complies with subsection (a) of this Section; and

• (2) The elevation (in relation to mean sea level) of the bottom of the lowest horizontal structural member of the lowest floor (excluding pilings or columns) of all new and substantially improved structures, and whether such structures contain a basement.

• (Formerly 10-7.406; Ord. 279 Div. 1 (part), 1989; Ord. 449 § 1 (part), 2009)

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City of Hercules, CA

Sec. 10-7.601

LAND USE

Sec. 10-7.602