Flood Hazard Areas Regulations

Flood Hazard Regulations - Updated June 19, 2020
The purpose of flood hazard regulations is to avoid and minimize damage to life and property from flooding events. Flood hazard areas are mapped on Federal Emergency Management Agency (FEMA) Federal Insurance Rate Maps (FIRMs). Flood insurance is available to development that is allowed to be located in designated flood prone areas from the National Flood Insurance Program (NFIP). 

To participate in the NFIP, the city of Mountlake Terrace must adopt and enforce a flood hazard reduction ordinance. Minimum requirements of the FEMA NFIP must be met. Participation ensures that properties in the city can receive the lowest possible insurance rates. It also ensures the city is eligible for emergency disaster relief funding. It is therefore in the best interest of the city and its residents to participate in this program.

Proposed Flood Regulations
The proposed 2020 revisions did not make substantive changes, only expanding on descriptions of how a use or development is allowed in a flood area. Much of the existing regulations are being relocated into a separate chapter of city code (Chapter 16.15 - Frequently Flooded Areas). 

Flood Prone Area Maps
The updated maps became effective June 19, 2020. There is little or no change to the floodplain delineation from previous FIRMs. The scale the maps are prepared at is too small to track minor differences. If there is a question about the actual flood elevation, a professional engineer or surveyor may be required to evaluate site conditions and submit a flood elevation certificate to FEMA for a determination. 

Hall Creek Flooding 12.02.2007Hall Creek Flooding in Mountlake Terrace

Flooding at Lake Ballinger Dock

Lake Ballinger Dock December 2007

Periodically, the Federal Emergency Management Agency (FEMA) revises flood hazard maps and flood regulation standards. FEMA has made changes to the regulations and will issue new maps, effective June 19, 2020. Current city code is not fully compliant with the revised standards set forth by FEMA, including adoption of the most current insurance rate maps for Mountlake Terrace.

The City desires to continue to participate in the NFIP. Therefore, an update to the current regulations is necessary. The proposed update is consistent with the minimum requirements to meet the NFIP standards and Washington State Department of Ecology requirements. The proposed adoption schedule, existing and proposed regulations, maps, memos and other documents can be viewed via links below. 

Current Flood Regulations

The city’s current flood hazard regulations were adopted in 2018 as part of the updated Critical Areas Ordinance, Chapter 16.15 of the Mountlake Terrace Municipal Code (MTMC). The regulations are contained in section MTMC 16.15.440. They define permitted uses, construction elevation above flood levels, flood-proofing standards, certification requirements, making changes to the maps, and other standards in flood hazard areas.

Hall Creek Flooding at 216th

Hall Creek at 216th_12.20.2019

2016 and 2020 FEMA FIRM Maps, Planning Commission/City Council Presentations and Documents


WA DOE Webmap