Article 5 — Provision for Flood Hazard Reduction[[4]]

Footnotes:

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Editor's note— Ord. No. 853, § 3, adopted Oct. 20, 2022, amended Article 5 in its entirety to read as herein set out. Former Article 5, §§ 9-8.501—9-8.506, pertained to similar subject matter, and derived from Ord. No. 776, § 1(Exh. A), effective Sept. 5, 2014.

(a)

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

(1)

Anchoring.

a.

All new construction and substantial improvements of structures, including manufactured homes and accessory dwelling units or junior accessory dwelling units (ADU's or JADU's), 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.

All manufactured homes and ADU's and JADU's shall meet the anchoring standards of Section 9-8.504.

(2)

Construction materials and methods.

a.

All new construction and substantial improvements 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.

If within zones AH or AO, so that there are adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures.

(3)

Elevation and flood proofing (See Section 9-8.202, Definitions for "Basement", "Lowest floor", "New construction", "Substantial damage" and "Substantial improvement").

a.

Residential construction, new or substantial improvement, shall have the lowest floor, including basement;

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. (The State of California recommends that in AO zones without velocity the lowest floor be elevated above the highest adjacent grade to a height exceeding the depth number specified in feet on the FIRM by at least two (2) feet, or elevated at least four (4) feet above the highest adjacent grade if no depth number is specified.)

2.

In an A zone, elevated to or above the base flood elevation, said base flood elevation shall be determined by one of the methods on Section 9-8.403(a)(2) of this chapter. (The State of California recommends the lowest floor be elevated at least two (2) feet above the base flood elevation, as determined by the community.)

3.

In all other zones, elevated to or above the base flood elevation. (The State of California recommends the lowest floor be elevated at least two (2) feet above the base flood elevation.) Upon completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor and verified by the Community Building Inspector of the City to be properly elevated. Such certification and verification shall be provided to the Floodplain Administrator.

b.

Nonresidential construction, whether new construction or substantial improvement, shall either be elevated to conform with Section 9-8.501(a)(3)a. of this article or, together with attendant utility and sanitary facilities;

1.

Be flood proofed below the elevation recommended under Section 9-8.501(a)(3)a. of this article so that the structure is watertight with walls substantially impermeable to the passage of water;

2.

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

3.

Be certified by a registered professional engineer or architect that the standards of Section 9-8.501(a)(3)b. of this article are satisfied. Such certification shall be provided to the Floodplain Administrator.

c.

All new construction and substantial improvement 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 exceed the following minimum criteria:

1.

Have a minimum of two (2) openings having a total net area of not less than one (1) square inch for every square foot of enclosed area subject to flooding. The bottom of all openings shall be no higher than one (1) foot above grade. Openings may be equipped with screens, louvers, valves or other coverings or devices, provided that they permit the automatic entry and exit of floodwater; or

2.

Be certified by a registered professional engineer or architect.

d.

Manufactured homes shall also meet the standards in Section 9-8.504.

(Ord. No. 853, § 3, eff. 10-20-2022)

(a)

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

(1)

Infiltration of floodwaters into the systems; and

(2)

Discharge from systems into floodwaters.

(b)

On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.

(Ord. No. 853, § 3, eff. 10-20-2022)

(a)

All preliminary subdivision proposals shall identify the flood hazard area and the elevation of the base flood.

(b)

All subdivision plans will provide the elevation of proposed structure(s) and pad(s). If the site is filled above the base flood elevation, the lowest floor and pad elevations shall be certified by a registered professional engineer or surveyor and provided to the Floodplain Administrator.

(c)

All subdivision proposals shall be consistent with the need to minimize flood damage.

(d)

All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.

(e)

All subdivisions shall provide adequate drainage to reduce exposure to flood hazards.

(f)

All new subdivisions proposals and other proposed development, including proposals for manufactured and ADU's and JADU's 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 (SFHAA) 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:

a.

Lowest floor elevation.

b.

Pad elevation.

c.

Lowest adjacent grade.

(Ord. No. 853, § 3, eff. 10-20-2022)

(a)

All manufactured homes that are placed or substantially improved within zones A1-30, AH, and AE on the community's flood insurance rate map, 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 on a site upon which a manufactured home has incurred substantial damage (see "substantial damage" definition) as a result of a flood, shall be elevated on a permanent foundation such that the lowest floor is elevated to or above base flood elevation (the State of California recommends at least two (2) feet above the base flood elevation) and be securely fastened to an adequately anchored foundation system to resist flotation, collapse and lateral movement.

(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, and AE on the community's flood insurance rate map that are not subject to the provisions of 9-8.504(a) will be securely fastened to an adequately anchored foundation to resist flotation collapse and lateral movement, and will be elevated so that either:

(1)

The lowest floor of the manufactured home is at or above the base flood elevation (the State of California recommends at least two (2) feet above the base flood elevation); or

(2)

The 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.

(3)

Upon completion of the structure, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor, and verified by the community building inspector, to be properly elevated. Such certification and verification shall be provided to the Floodplain Administrator.

(c)

Manufactured homes placed within manufactured home parks or subdivisions shall meet the standards in Section 9-8.504. All manufactured homes in special flood hazard areas shall meet the anchoring standards in Section 9-8.501(a), construction materials and methods requirements in Article 5.501.1 and flood openings requirements in Section 9-8.504(a).

(Ord. No. 853, § 3, eff. 10-20-2022)

(a)

All recreational vehicles placed on sites within zones A1-30, AH and AE on the community's flood insurance rate map will either:

(1)

Be on the site for fewer than 180 consecutive days, and 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

(2)

Meet the permit requirements of Article 4 of this chapter and the elevation and anchoring requirements for manufactured homes in Section 9-8.504(a).

(Ord. No. 853, § 3, eff. 10-20-2022)

(a)

Located within areas of special flood hazards established in Section 9-8.302 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters which carry debris, potential projectiles and erosion potential, the following provisions shall apply:

(1)

Encroachments, including fill, new construction, substantial improvement and other new development, are prohibited unless certification by a registered professional engineer or architect is provided, demonstrating that encroachments will not result in any increase in the base flood elevation during the occurrence of the base flood discharge.

(2)

If subsection (a) of this section is satisfied, all new construction, substantial improvement and other proposed new development shall comply with all other applicable flood hazard reduction provisions of this Article 5.

(Ord. No. 853, § 3, eff. 10-20-2022)

(a)

ADU building standards.

(1)

The ADU shall not exceed a single story, unless constructed above a detached garage, or the height limit of the applicable zoning district, whichever is more restrictive.

(2)

The floor area of the ADU together with the floor area of the primary dwelling unit shall not cause the parcel coverage for the subject site to exceed the maximum allowable lot coverage for the applicable zoning district.

(3)

The development of the ADU shall be subject to the property development standards for the subject zoning district in which the ADU is located.

(4)

Both attached and detached ADUs must be architecturally compatible, having similar materials and style of construction, with the primary dwelling and consistent with the established character of the adjoining residential neighborhood. The design and size of the ADU shall conform to all applicable standards of the

building, health, and other codes adopted by the City. (Refer to Table 2-3 in Division 2 of this title for residential lot coverage requirements.)

(5)

Attached ADUs shall be compatible with and made structurally a part of the primary dwelling (e.g., share a common wall with the primary dwelling, rely partially on the primary dwelling for structural support, or be attached to the primary dwelling).

(6)

Detached ADUs shall comply with building and fire code separation standards and be compatible with the materials and colors of the primary dwelling.

(7)

No passageway is required in conjunction with the construction of an ADU.

(8)

Approval by the County Health Officer and City Public Utilities Director is required where a private water well and/or private sewage disposal system is being used.

(9)

Fire sprinklers are required for ADUs if fire sprinklers are required for the primary residence.

(10)

A new or separate utility connection directly between the ADU and the utility is not required unless the ADU is constructed with a new single-family home or a new detached structure.

(b)

JADU building standards. JADUs shall comply with the following:

(1)

A JADU must include a separate entrance from the main entrance to the proposed or existing single-family residence.

(2)

A JADU must include at least an efficiency kitchen, which includes a cooking facility with appliances and a food preparation counter and storage cabinets that are of reasonable size in relation to the size of the JADU.

(3)

A JADU may include separate sanitation facilities or may share sanitation facilities with the existing structure.

(4)

A JADU shall not be considered a separate or new dwelling unit for purposes of any fire or life protection ordinance or regulation, or for purposes of providing water, sewer, or power, including a connection fee.

(5)

Deed restriction. A JADU shall not be permitted unless a deed restriction, which shall run with the land, is recorded for the applicable lot, and filed with the City along with the permit application, and must do both of the following:

(6)

Prohibit the sale of the JADU separate from the sale of the single-family residence and include a statement that the deed restriction may be enforced against future purchasers.

(7)

Restrict the size and attributes of the JADU that conform with this section.

(c)

Multifamily ADUs. The following ADUs are permitted within a residential or mixed-use zone on a lot that has an existing multifamily dwelling:

(1)

One (1) or more ADUs, up to twenty-five (25) percent of the existing multifamily dwelling units, constructed within the portions of the existing multifamily dwelling structure that are not used as livable space, including, but not limited to, storage rooms, boiler rooms, passageways, attics, basements, or garages, if each unit complies with state building standards for dwellings.

(2)

Up to two (2) detached ADUs, subject to a height limit of sixteen (16) feet and four-foot rear yard and side setbacks.

(Ord. No. 853, § 3, eff. 10-20-2022)