A. 
New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated one foot above the base flood level. Mechanical equipment and utilities shall be waterproof or elevated at least one foot above the BFE.
B. 
Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or 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 meet or exceed the following minimum criteria:
1. 
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.
2. 
The bottom of all openings shall be no higher than one foot above grade.
3. 
Openings may be equipped with screens, louvers, or other coverings or devices; provided, that they permit the automatic entry and exit of floodwaters.
4. 
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 and exit of floodwaters.
(Ord. 419 § 5.2-1, 1989; Ord. 937 § 1, 2005; Ord. 1208 § 1 (Exh. A), 2020)
New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall meet the requirements of subsection A or B of this section.
A. 
New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall meet all of the following requirements:
1. 
In AE and A1-30 zones or other A zoned areas where the BFE has been determined or can be reasonably obtained:
New construction and substantial improvement of any commercial, industrial, or other nonresidential structure shall have the lowest floor, including basement, elevated one foot or more above the BFE, or elevated as required by ASCE 24, whichever is greater. Mechanical equipment and utilities shall be waterproofed or elevated at least one foot above the BFE, or as required by ASCE 24, whichever is greater.
2. 
If located in an unnumbered A zone for which a BFE is not available and cannot be reasonably obtained, the structure shall be reasonably safe from flooding, but in all cases the lowest floor shall be at least two feet above the highest adjacent grade.
3. 
Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, or 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 must meet or exceed the following minimum criteria:
a. 
Have a minimum of two openings with a total net area of not less than one square inch for every square foot of enclosed area subject to flooding.
b. 
The bottom of all openings shall be no higher than one foot above grade.
c. 
Openings may be equipped with screens, louvers, valves, or other coverings or devices; provided, that they permit the automatic entry and exit of floodwater.
d. 
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 and exit of floodwaters.
Alternatively, a registered engineer or architect may design and certify engineered openings.
B. 
If the requirements of subsection A of this section are not met, then new construction and substantial improvement of any commercial, industrial or other nonresidential structure shall meet all of the following requirements:
1. 
Be dry floodproofed so that below one foot or more above the base flood level the structure is watertight with walls substantially impermeable to the passage of water or dry floodproofed to the elevation required by ASCE 24, whichever is greater;
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 design and methods of construction are in accordance with accepted standards of practice for meeting provisions of this subsection based on their development and/or review of the structural design, specifications and plans. Such certifications shall be provided to the official as set forth in LFPMC § 16.20.310(B).
(Applicants who are floodproofing nonresidential buildings shall be notified that flood insurance premiums will be based on rates that are one foot below the floodproofed level (e.g., a building floodproofed to the base flood level will be rated as one foot below). Floodproofing the building an additional foot will reduce insurance premiums.)
(Ord. 419 § 5.2-2, 1989; Ord. 937 § 1, 2005; Ord. 1208 § 1 (Exh. A), 2020)
Construction of new critical facilities shall be, to the extent possible, located outside the limits of the base floodplain. Construction of new critical facilities shall be permissible within the base floodplain if no feasible alternative site is available. Critical facilities constructed within the base floodplain shall have the lowest floor elevated to three feet or more above the level of the base flood elevation at the site. Floodproofing and sealing measures must be taken to ensure that toxic substances will not be displaced by or released into floodwaters. Access routes elevated to or above the level of the base floodplain shall be provided to all critical facilities to the extent possible.
(Ord. 419 § 5.2-3, 1989; Ord. 937 § 1, 2005; Ord. 1208 § 1 (Exh. A), 2020)
All manufactured homes to be placed or substantially improved within zones Al through A30, AH and AE on the community's FIRM shall be elevated on a permanent foundation such that the lowest floor of the manufactured home is one foot or more above the base flood elevation; and be securely anchored to an adequately anchored foundation system in accordance with the provisions of LFPMC § 16.20.350(B).
(Ord. 419 § 5.2-4, 1989; Ord. 937 § 1, 2005; Ord. 1208 § 1 (Exh. A), 2020)
Recreational vehicles placed on sites are required to either:
A. 
Be on the site for fewer than 180 consecutive days; or
B. 
Be fully licensed and ready for highway use, on wheels or jacking systems, attached to the site only by quick disconnect-type utilities and security devices, and have no permanently attached additions; or
C. 
Meet the requirements of LFPMC § 16.20.440 and the elevation and anchoring requirements for manufactured homes.
(Ord. 937 § 1, 2005; Ord. 1208 § 1 (Exh. A), 2020)
If buildings or manufactured homes are constructed or substantially improved with fully enclosed areas below the lowest floor, the areas shall be used solely for parking of vehicles, building access, or storage.
(Ord. 419 § 5.3, 1989; Ord. 937 § 1, 2005; Ord. 1208 § 1 (Exh. A), 2020)
A. 
Appurtenant structures used solely for parking of vehicles or limited storage may be constructed such that the floor is below the BFE, provided the structure is designed and constructed in accordance with the following requirements:
1. 
Use of the appurtenant structure must be limited to parking of vehicles or limited storage;
2. 
The portions of the appurtenant structure located below the BFE must be built using flood resistant materials;
3. 
The appurtenant structure must be adequately anchored to prevent flotation, collapse, and lateral movement;
4. 
Any machinery or equipment servicing the appurtenant structure must be elevated or floodproofed to or above the BFE;
5. 
The appurtenant structure must be designed to allow for the automatic entry and exit of floodwaters in accordance with LFPMC § 16.20.410(B);
6. 
The structure shall have low damage potential;
7. 
If the structure is converted to another use, it must be brought into full compliance with the standards governing such use; and
8. 
The structure shall not be used for human habitation.
B. 
Detached garages, storage structures, and other appurtenant structures not meeting the above standards must be constructed in accordance with all applicable standards in LFPMC § 16.20.410.
C. 
Upon completion of the structure, certification that the requirements of this section have been satisfied shall be provided to the floodplain administrator for verification.
(Ord. 1208 § 1 (Exh. A), 2020)
To the maximum extent possible, avoid the short- and long-term adverse impacts associated with the destruction or modification of wetlands, especially those activities which limit or disrupt the ability of the wetland to alleviate flooding impacts. The following process should be implemented:
A. 
Review proposals for development within base floodplains for their possible impacts on wetlands located within the floodplain.
B. 
Ensure that development activities in or around wetlands do not negatively affect public safety, health and welfare by disrupting the wetlands' ability to reduce flood and storm drainage.
C. 
Request technical assistance from the Department of Ecology in identifying wetland areas. Existing wetland map information from the National Wetlands Inventory (NWI) can be used in conjunction with the community's FIRM to prepare an overlay zone indicating critical wetland areas deserving special attention.
(Ord. 419 § 5.4, 1989; Ord. 937 § 1, 2005; Ord. 1208 § 1 (Exh. A), 2020)
In areas with BFEs (when a regulatory floodway has not been designated), no new construction, substantial improvements, or other development (including fill) shall be permitted within zones A1-30 and AE on the community's FIRM, unless it is demonstrated 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 foot at any point within the community.
(Ord. 1208 § 1 (Exh. A), 2020)
All development, including manmade changes to improved or unimproved real estate for which specific provisions are not specified in this chapter or the state building codes with adopted amendments and any city of Lake Forest Park amendments, shall:
A. 
Be located and constructed to minimize flood damage;
B. 
Meet the encroachment limitations of this chapter if located in a regulatory floodway;
C. 
Be anchored to prevent flotation, collapse, or lateral movement resulting from hydrostatic loads, including the effects of buoyancy, during conditions of the design flood;
D. 
Be constructed of flood damage-resistant materials;
E. 
Have mechanical, plumbing, and electrical systems above the design flood elevation or meet the requirements of ASCE 24, except that minimum electric service required to address life safety and electric code requirements is permitted below the design flood elevation provided it conforms to the provisions of the electrical part of building code for wet locations.
(Ord. 419 § 5.5, 1989; Ord. 937 § 1, 2005; Ord. 1208 § 1 (Exh. A), 2020)