San Ramon Municipal Code Art. 3 Construction Standards

In all areas of special flood hazards the standards set out in this article are required. (Ord. No. 414, §§ 1, 2, 4-28-2009)

A. All new construction and substantial improvements shall be 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 shall be the anchoring standards of Section C4-70 of this chapter. (Ord. No. 414, §§ 1, 2, 4-28-2009)

A. All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage. B. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.

City of San Ramon, CA | Municipal Code 411

C. All new construction and substantial improvements shall be constructed 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. D. Require within Zones AH or AO adequate drainage paths around structures on slopes to guide floodwaters around and away from proposed structures. (Ord. No. 414, §§ 1, 2, 4-28-2009)

A. New construction and substantial improvement of any structure shall have the lowest floor, including basement, elevated to or above the base flood elevation. Nonresidential structures may meet the standards in Subsection C of this section. Upon the completion of the structure the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor, or verified by the city building inspector to be properly elevated. Such certification or verification shall be provided to the floodplain administrator in the FEMA approved format. B. New construction and substantial improvement of any structure in Zone AE, AH, A1-30 or AO shall have the lowest floor, including basement, elevated above the base flood elevation, or at least two feet if no depth number is specified on the FIRM. Nonresidential structures may meet the standards in Subsection A or B of this section. Upon the completion of the structure the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor, or verified by the city building inspector to be properly elevated. Such certification or verification shall be provided to the floodplain administrator. C. Nonresidential construction shall either be elevated in conformance with Subsection A or B of this section, or together with attendant utility and sanitary facilities: 1. Be floodproofed so that below the base flood level 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 of buoyancy; 3. Be certified by a registered professional engineer or architect that the standards of this subsection are satisfied. Such certifications shall be provided to the floodplain administrator. D. Garages and Low Cost Accessory Structures. 1. Attached Garages. a. 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 Section C4-67E. Areas of the garage below the BFE must be constructed with flood resistant materials. See Section C4-66. b. 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. 2. Detached Garages and Accessory Structures. a. "Accessory structures" used solely for parking (two-car detached garages or smaller) or limited storage (small, low-cost sheds), as defined in Section C4-49, may be constructed such that its floor is below the base flood elevation (BFE), provided the structure is designed and constructed in accordance with the following requirements: i. Use of the accessory structure must be limited to parking or limited storage;

City of San Ramon, CA | Municipal Code 412

ii. The portions of the accessory structure located below the BFE must be built using flood-resistant materials; iii. The accessory structure must be adequately anchored to prevent flotation, collapse and lateral movement; iv. Any mechanical and utility equipment in the accessory structure must be elevated or floodproofed to or above the BFE; v. The accessory structure must comply with floodplain encroachment provisions in Section C4-72; and vi. The accessory structure must be designed to allow for the automatic entry of flood waters in accordance with Section C4-67E.

Detached garages and accessory structures not meeting the above standards must be constructed in accordance with all applicable standards in Article 3.

E. Require, for all new construction and substantial improvements, that fully enclosed areas below the lowest floor excluding basements that are subject to flooding shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect or meet or exceed the following minimum criteria: 1. Either a minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided. The bottom of all openings shall be no higher than one foot above grade. Opening may be equipped with screens, louvers, valves or other coverings or devices provided that they permit the automatic entry and exit of floodwaters; or 2. Be certified to comply with a local floodproofing standard approved by the Federal Insurance Administration. F. Manufactured homes shall also meet the standards in Section C4-70 of this chapter. (Ord. No. 414, §§ 1, 2, 4-28-2009)

A. All new and replacement water supply and sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the system and 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. 414, §§ 1, 2, 4-28-2009)

A. All preliminary subdivision proposals shall identify the flood hazard area and the elevation of the base flood. B. All final subdivision plans will provide the elevation of proposed structure(s) and pads. If the site is filled above the base flood, the final pad elevation 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.

City of San Ramon, CA | Municipal Code 413

(Ord. No. 414, §§ 1, 2, 4-28-2009)

All new and replacement manufactured homes and additions to manufactured homes shall: A. Be elevated so that the lowest floor is at or above the base flood elevation; and B. Be securely anchored to a permanent foundation system to resist flotation, collapse or lateral movement. (Ord. No. 414, §§ 1, 2, 4-28-2009)

All recreational vehicles placed in Zones A1-30, AH, and AE will either: A. Be on the site for fewer than one hundred eighty consecutive days; or B. 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 C. Meet the permit requirements of Section C4-61 of this chapter and the elevation and anchoring requirements for manufactured homes in Section C4-70. (Ord. No. 414, §§ 1, 2, 4-28-2009)

Located within areas of special flood hazard established in Section C4-43 of this chapter 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 apply: A. Prohibit encroachments, including fill, new construction, substantial improvements and other development unless certification by a registered professional engineer or architect is provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge. B. If subsection A of this section is satisfied, all new construction and substantial improvements shall comply with all other applicable flood hazard reduction provisions of this article. (Ord. No. 414, §§ 1, 2, 4-28-2009)

A. No development activities shall be permitted within Zones A1-30 and AE where base flood elevations are included in the FIS or on the FIRM but no floodways have been designated, unless the following is true: The applicant has submitted with the site plan and construction documents hydrologic and hydraulic analyses that are signed and sealed by a registered professional engineer, demonstrating that the cumulative effect of the proposed development, when combined with all other existing and anticipated flood hazard area encroachments, will not increase the base flood elevation more than one (1) foot at any point within the City. (Ord. No. 508, § 1, 06/22/2021)

Effective on: 7/22/2021

C4-74 through C4-80. Reserved.

City of San Ramon, CA | Municipal Code 414

(Ord. No. 508, § 1, 06/22/2021)

Effective on: 7/22/2021