In all areas of special flood hazard, the following standards are required:
A. 
Finished Grade After Construction.
1. 
After construction or other development, but prior to final building inspection, certificate of occupancy or other final approval, the applicant shall obtain and furnish to the city a topographic survey, prepared by a licensed surveyor or engineer, with sufficient scale and contour to interval to adequately assess variation in ground surface and determine the average grade after construction or development, unless the requirement for a topographic survey was waived at the time of application.
2. 
The average finished grade of all lots, tracts or parcels after construction of a building or other development, excluding the area occupied by the above-grade building or other development, shall be no greater than the average grade of the lot prior to construction or development. After construction or other development but prior to final building inspection, the applicant shall furnish, together with the topographic survey, the written certification of the licensed surveyor or engineer preparing the topographic survey that the finished grade meets the requirement of this subsection. No building or other development shall be occupied or used if the requirements of this section are not met.
3. 
Any earth material that must be removed from a site in order to comply with the requirements of this chapter shall be transported to an approved disposal site at the applicant's or property owner's sole expense, and evidence of such disposal shall be furnished to the floodplain administrator.
B. 
Anchoring.
1. 
All new construction and substantial improvements, including those related to manufactured homes, shall be anchored to prevent flotation, collapse or lateral movement of the structure, resulting from hydrodynamic and hydrostatic loads including the effects of buoyancy, pursuant to a design prepared by a registered professional engineer or architect licensed by the state of Washington.
2. 
All manufactured homes shall be anchored to prevent flotation, collapse or lateral movement, 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. All anchoring designs shall be prepared by a registered professional engineer or architect.
C. 
Construction Materials and Methods.
1. 
All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.
2. 
All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage.
3. 
Electrical, heating, ventilation, plumbing and air-conditioning equipment and other service facilities shall be elevated at least one foot about the BFE so as to prevent water from entering or accumulating within the components during conditions of flooding.
D. 
Utilities.
1. 
All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the system.
2. 
New water wells shall be located on high ground that is not in the floodway.
3. 
New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems and discharge from the systems into floodwaters.
4. 
On-site waste disposal systems, if otherwise permitted, shall be located to avoid impairment to them or contamination from them during flooding.
E. 
Subdivision, Short Subdivision, Binding Site Improvement Plan and Commercial and Multifamily Site Plan Approval Proposals as Well as New Development Within Areas of Special Flood Hazard.
1. 
All subdivision, short subdivision, binding site improvement plan and commercial and multifamily site plan proposals, as well as new development within areas of special flood hazard shall be subject to the provisions of this subsection.
2. 
All proposals shall be consistent with the need to minimize flood damage.
3. 
All proposals shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.
4. 
All proposals shall have adequate drainage provided to reduce exposure to flood damage.
5. 
Where subdivision, short subdivision, binding site improvement plan, and commercial and multifamily site plan proposals contain more than 50 lots and/or more than five acres, base flood elevation data shall be provided as part of the application.
6. 
All proposals shall be reviewed for, and may be denied or conditioned upon, their effect upon storage and conveyance of floodwaters. The design of all projects shall be reviewed specifically (without limitation of review for compliance with all other requirements) to ensure compliance with the requirements of SMC § 15.12.160(E) and to eliminate potential flood barriers to the maximum degree possible.
7. 
No subdivision proposal shall be approved until the application has been submitted to the Department of Ecology and the floodplain administrator has either received the comments of the Department of Ecology or confirmed in writing that the Department of Ecology does not intend to submit comments.
F. 
Review of Building Permits. Where elevation data is not available either through the flood insurance study, FIRM, or from another authoritative source per SMC § 15.12.120(C), applications for building permits for floodplain development shall not be granted until base flood elevation data is established.
G. 
Storage of Materials and Equipment.
1. 
The storage or processing of materials that could be injurious to human, animal, or plant life if released due to damage from flooding is prohibited in special flood hazard areas.
2. 
Storage of other material or equipment may be allowed by the floodplain administrator if, in their sole determination, such material or equipment is not subject to damage by floods and is firmly anchored to prevent flotation, or is readily removable from the area within the time available after flood warning.
H. 
Building Height. Within the area of special flood hazard, building height shall be measured as follows:
1. 
For buildings that are elevated as described in SMC § 15.12.160(A), (B)(1), (C), or (E), height shall be measured from the BFE plus any required freeboard (e.g., one foot). In case of any conflict or inconsistency between this subsection and the provisions of SMC § 17.10.020(GG), this subsection shall govern.
2. 
For buildings that are floodproofed as described in SMC § 15.12.160(B)(2), or otherwise not elevated, height shall be measured as described in SMC § 17.10.020(GG).
(Ord. 1237 § 1, 2020)
A. 
Residential Construction.
1. 
In AE zones, where the BFE has been determined or can be reasonably obtained, new construction and substantial improvement of any residential structure shall have the lowest floor (including basement) elevated to at least one foot above the base flood elevation. Mechanical equipment shall be elevated at least one foot above the BFE. Utilities shall be waterproof or elevated at least one foot above the BFE.
2. 
Fully enclosed areas below the lowest floor that are subject to flooding are prohibited, unless they are 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 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 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;
b. 
The bottom of all openings shall be no higher than one foot above grade; and
c. 
Openings may be equipped with screens, louvers, valves, or other coverings or devices; provided, that they permit the automatic entry and exit of floodwaters and do not otherwise inhibit the flow of floodwaters.
B. 
Nonresidential Construction. New construction and substantial improvement of any commercial, industrial, or other nonresidential structure shall meet the requirements of subsection (B)(1) or (B)(2) of this section:
1. 
New construction and substantial improvement of any commercial, industrial or other nonresidential structure shall meet all of the following requirements:
a. 
In AE zones where the BFE has been determined or can be reasonably obtained, the lowest floor, including basement, shall be elevated one foot or more above the BFE or to the elevation required by ASCE 24, whichever is greater. Mechanical equipment shall be elevated at least one foot above the BFE. Utilities shall be waterproof up to at least one foot above the BFE, or elevated at least one foot above the BFE; and
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 shall be certified by a registered professional engineer or architect and must meet or exceed the following criteria:
i. 
Have 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;
ii. 
The bottom of all openings shall be no higher than one 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 floodwaters and do not otherwise inhibit the flow of floodwaters.
2. 
If the requirements of subsection (B)(1) of this section are not met or cannot be met, then new construction and substantial improvement of any commercial, industrial, or nonresidential structure shall meet all of the following requirements:
a. 
Be dry floodproofed up to at least one foot above the BFE such that the structure is watertight with walls substantially impermeable to the passage of water;
b. 
Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy;
c. 
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 the provisions of this subsection based on their development and/or review of the structural design, specifications and plans, and such certification is provided to the building official.
3. 
Applicants for floodproofing nonresidential buildings shall be notified that flood insurance premiums will be based on rates that are one foot below the floodproofed level; for example, a building floodproofed to one foot above the base flood level will be rated as at the base flood level.
C. 
Manufactured Homes.
1. 
All manufactured homes to be placed or substantially improved on sites within the area of special flood hazard 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 shall be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement.
2. 
Mechanical equipment for manufactured homes shall be elevated at least one foot above the BFE. Utilities for manufactured homes shall be waterproof up to at least one foot above the BFE, or elevated at least one foot above the BFE.
3. 
For purposes of this section, "substantial damage" of a manufactured home shall mean any damage the cost of which to repair or reconstruct exceeds 50 percent of the market value of the manufactured home before the repair or reconstruction is started.
D. 
Recreational Vehicles. Recreational vehicles placed on site within zones A1-30, AH and AE on the FIRM shall be on the site fewer than 180 consecutive days, and either:
1. 
Be fully licensed and ready for highway use, on wheels or jacking system, attached to the site only by quick disconnect type utilities and security devices, and have no permanent attached additions; or
2. 
Meet the requirements of the elevation and anchoring requirements for manufactured homes in subsection C of this section.
E. 
Critical Facilities. Construction of new critical facilities shall be, to the greatest extent possible, located outside of the limits of the special flood hazard area (SFHA or 100-year floodplain). Construction of new critical facilities shall be permissible within the SFHA if no feasible alternative site is available. Critical facilities constructed within the SFHA shall have the lowest floor elevated to three feet or more above the base flood elevation at the site or to the height of the 500-year flood, whichever is higher. 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 flood elevation shall be provided to all critical facilities to the extent possible.
F. 
Fill.
1. 
Subject to the provisions of subsection (F)(2) of this section, no fill shall be permitted except where provision has been made on the subject property to balance the capacity to store floodwaters and accommodate potential surface flow in an amount equal to the amount of floodwater likely to be displaced by the fill; provided, provision may be made to balance the capacity to store floodwaters off the subject property, when it can be demonstrated that the property upon which the balancing capacity is being created is located such that no increase in the base flood discharge will result. Care shall be taken to prevent erosion and surface runoff to adjacent properties. All fill shall be compacted at the time of placement.
2. 
Any person may place not more than five cubic yards of material used solely for landscape maintenance or gardening at a residence or business in any one calendar year; provided, such activity requires a flood improvement permit from the floodplain administrator. Such right shall not be assignable, nor shall it carry over from year to year or otherwise be cumulative.
3. 
Fill within the floodway shall comply with the provisions of SMC § 15.12.170.
G. 
Clearing and Grading. Clearing and grading shall be approved only when the application provides:
1. 
A plan and profile of the site to be cleared;
2. 
Identification of the flora to be protected, or removed;
3. 
A reclamation plan to prevent erosion; and
4. 
A drainage plan in accordance with Chapter 12.16 SMC, where a street project is proposed.
H. 
Bank Improvements. Where proposed development or improvements include modification or work along the banks of the Snoqualmie River or Kimball Creek, application shall first be made to the State Department of Fisheries and Game for a State Hydraulics Permit. Application for the permit required by this chapter shall not be made until after the state permit is approved, and a certified copy has been provided to the city.
I. 
Hazardous Materials.
1. 
The placement, transfer or storage of chemicals, petroleum products or by-products, fertilizers, insecticides, pesticides, lime, cement or other material that, when inundated, will constitute a hazard to life, health and safety, or adversely affect the quality of surface waters, in quantities greater than those declared to be exempt pursuant to the Uniform Building Code is prohibited within areas of special flood hazard.
2. 
Where a clearing and grading permit is sought in connection with any development for which a shorelines substantial development permit is required, the application shall be reviewed by the city shorelines administrator prior to issuance of a clearing and grading permit.
J. 
Enclosed Areas Below the Lowest Floor.
1. 
If buildings or manufactured homes are constructed or substantially improved with fully enclosed areas below the lowest flood, these areas shall be used solely for parking of vehicles, building access, or storage.
2. 
Subgrade Crawlspaces. A subgrade crawlspace may be allowed when it meets the requirements of FEMA Technical Bulletin 11-01, including all of the following:
a. 
The interior grade of the crawl space is not more than two feet below the lowest adjacent exterior grade;
b. 
The height of the crawl space from the interior grade of the crawl space to the top of the crawl space foundation wall does not exceed four feet;
c. 
There is a drainage system that removes interior floodwaters; and
d. 
The velocity of floodwaters at the site is not more than five feet per second.
K. 
Accessory Structures. For A Zones:
1. 
Accessory 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:
a. 
Use of the accessory structure shall be limited to parking of vehicles or limited storage;
b. 
The portions of the accessory structure located below the BFE shall be built using flood resistant materials;
c. 
The accessory structure shall be adequately anchored to prevent flotation, collapse, and lateral movement;
d. 
Any mechanical equipment servicing the accessory structure shall be elevated at least one foot above the BFE;
e. 
Any utilities servicing the accessory structure shall be waterproof up to at least one foot above the BFE, or elevated at least one foot above the BFE;
f. 
The accessory structure must comply with floodway encroachment provisions in SMC § 15.12.170;
g. 
The accessory structure shall be designed to allow for the automatic entry and exit of floodwaters in accordance with subsection (B)(1)(b) of this section.
h. 
The structure shall have low damage potential;
i. 
If the structure is converted to another use, it shall be brought into full compliance with the standards governing such use; and
j. 
The structure shall not be used for human habitation.
2. 
Detached garages, storage structures, and other accessory structures not meeting the standards in subsection (K)(1) of this section shall be constructed in accordance with all applicable standards in subsection A of this section.
3. 
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. 1237 § 1, 2020)
Located within areas of special flood hazard 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 increase erosion potential, the following provisions apply in all areas designated as floodways on the FIRM:
A. 
Encroachments Prohibited. No encroachments, including fill, new construction, substantial improvements, or other development shall be permitted within the floodway unless certification by a registered professional engineer is provided demonstrating through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that the proposed encroachment would not result in any increase in flood levels during the occurrence of the base flood discharge.
B. 
Residential Construction Prohibited. No new construction or reconstruction of residential structures shall be permitted within the floodway, except for the following:
1. 
Repairs, reconstruction or improvements to a structure which do not increase the ground floor area; and
2. 
Repairs, reconstruction or improvements to a structure, the cost of which does not exceed 50 percent of the market value either:
a. 
Before the repair, reconstruction or improvement is commenced; or
b. 
If the structure has been damaged, and is being restored, before the damage occurred. Any project for improvement of a structure to correct existing violations of state or local health, sanitary or safety code specifications which have been identified by the local code enforcement official and are the minimum necessary to assure safe living conditions or to structures identified as historic places shall not be included in the 50 percent limitation.
C. 
If the requirements of subsection A of this section are met, all new construction and substantial improvement shall comply with all other applicable flood hazard reduction standards of this chapter.
(Ord. 1237 § 1, 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 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 city.
(Ord. 1237 § 1, 2020)
A. 
Appeals of Actions of the Floodplain Administrator. Any person with standing may appeal from any requirements, decision, determination, or other action of the floodplain administrator when it is alleged that there is an error in the administration of this chapter. All such appeals shall be made within 14 days of the issuance of the permit, decision, determination, or other action of the floodplain administrator by filing a written notice of appeal with the community development department. The notice shall identify the requirement, decision or determination alleged to be erroneous, and shall include information required by SMC § 2.14.100. Such appeal shall be heard by the hearing examiner within 60 days of the date of filing of the notice of appeal. The hearing examiner's decision shall be in writing and rendered per SMC § 2.14.120. The decision of the hearing examiner made pursuant to this subsection may be appealed to the King County superior court in accordance with the provisions of Chapter 36.70C RCW.
B. 
Appeals of Variance Decisions. Any person with standing may appeal a decision of the hearing examiner made pursuant to this chapter on a variance, to the city council. Appeals shall be filed within 14 days of the notice of decision for the variance and shall conform to the requirements of Chapter 14.40 SMC. The decision of the city council made pursuant to this subsection may be appealed to the King County superior court in accordance with the provisions of Chapter 36.70C RCW.
(Ord. 1237 § 1, 2020)