CUFP26-021 Staff Decision - Laserfiche WebLink

Home Browse Search

b. The bottom of all openings shall be no higher than one foot above grade; c. Openings may be equipped with screens, louvers, or other coverings or devices; provided, that they permit the automatic entry and exit of floodwaters; d. Interior grade of the crawlspace shall not exceed two feet below the lowest adjacent exterior grade; e. The height of the crawlspace when measured from the interior grade of the crawlspace (at any point on grade) to the bottom of the lowest horizontal structural member of the lowest floor shall not exceed four feet; f. An adequate drainage system that removes floodwaters from the interior area of the crawlspace shall be provided; g. The velocity of floodwaters at the site shall not exceed five feet per second for any crawlspace. For velocities in excess of five feet per second, other foundation types shall be used; and h. Below-grade crawlspace construction in accordance with the requirements listed above will not be considered basements for flood insurance purposes. However, below-grade crawlspace construction in the special flood hazard area is not the recommended construction method because of the increased likelihood of problems with foundation damage, water accumulation, moisture damage, and drainage. Applicants shall be advised that buildings constructed with below-grade crawlspaces will have higher flood insurance premiums than buildings that have the preferred crawlspace construction (the interior grade of the crawlspace is at or above the adjacent exterior grade); This shall be made a condition of approval. D. Anchoring. 1. 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. 2. All manufactured dwellings must likewise be anchored to prevent flotation, collapse or lateral movements, and shall be installed using methods and practices that minimize flood damage. Anchoring methods may include, but are not limited to, use of over-the-top or frame ties to ground anchors. Anchoring methods shall be consistent with the standards contained in the Oregon Manufactured Dwelling Installation Specialty Code. The applicant attests to compliance with this standard, and engineer certification shall be a conditional of approval. E. Construction Materials and Methods. 1. All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage, and the design and methods of construction are in accord with accepted standards of practice based on an engineer’s or architect’s review of the plans and specifications. 2. All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damages. The applicant attests to compliance with this standard. The criterion is met. F. Utilities. 1. All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the system as approved by the State Health Division. 2. New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters in the systems and discharge from the systems into floodwaters. 3. On-site waste disposal systems shall be designed and located to avoid impairment to them or contamination from them during flooding consistent with the requirements of the Oregon State Department of Environmental Quality. 4. Electrical, heating, ventilation, plumbing, duct systems, air-conditioning and other equipment and service facilities shall be elevated to one foot above the level of the base flood elevation. Where the base flood elevation is not available, the electrical, heating, ventilation, plumbing and