Critical Areas

State law defines critical areas as wetlands, frequently flooded areas, fish and wildlife habitat, geologically hazardous areas (steep slopes, erosion and landslide hazards) and critical aquifer recharge areas (RCW 36.70A). The regulations seek to protect the functions and values of these environmentally and geological features to provide for a healthy environment, public benefit, public safety and provide for reasonable use of these areas to property owners.

The City adopted a Critical Areas Ordinance in 2004, codified as Chapter 16.15 of the Mountlake Terrace Municipal Code (MTMC). The purpose of the critical areas regulations is to protect the functions and values of those areas at the local level. The City updated its Critical Areas regulation in 2018.

Why are critical areas important?
Critical areas perform a multitude of environmental functions that improve our water and air, protect property from damage, enhance quality of life, and support the local economy.

Wetlands, streams and floodplains help with flood attenuation, improve water quality, recharge the water table, and are a food chain support for flora and fauna. They provide habitat for fish and wildlife and allow for recreation such as bird watching, fishing, hiking, and hunting. Designated wildlife habitat supports certain species of bird and animal life, moderates summer and winter temperature fluctuations and absorbs storm water. Geologically hazardous slopes need to be protected to maintain their stability, reduce erosion and slippage and protect property from damage. Often, critical area types overlap and work in synergy. All critical areas provide open space for passive or active enjoyment. In short, critical areas matter.

Where are the critical areas located?
 Critical areas are located throughout the City so the regulations apply to a large number of properties. Known critical areas in the City are mapped. The maps are updated periodically to reflect new information. 

What do critical area regulations do?
The critical areas ordinance is a set of regulations to protect the functions and values of critical areas while also allowing for reasonable use of private property. Critical area regulations include requirements regarding buffers from streams and wetlands, critical wildlife habitat areas and steep slopes. Critical areas are to be avoided when at all possible. The regulations can restrict and may prohibit certain development or activities on a site due to its negative impact on one or more critical areas.

Generally speaking, no development activity may occur within a critical area or critical area buffer without a critical areas report being prepared and impacts of the development mitigated. Mitigation includes avoiding impacts, minimizing impacts, repairing, rehabilitating or restoring impacts, or replacing the critical area functions and values elsewhere.

What changes and updates will be mandated?

The state mandates include:

  • a clear emphasis on the preservation and protection of anadromous fish habitat
  • use of "Best Management Practices"
  • consistency with some specific development regulation, and
  • consistency with the City's Comprehensive Plan of 2015

Other updates consist of setting forth a clear process for when and what type of review is to occur for a development activity proposed near or in critical area, what information or special report the proponent is to provide, what procedural steps the proponent and staff are to follow in each situation, what the criteria are for staff to reach a decision, what the applicant needs to do to proceed with their development, adopt critical area map into regulations, imminent and non-imminent hazard trees, how to regulate isolated wetlands, require a permit, and make other changes that will improve the implementation of the regulations to protect both critical areas and property owner's rights. 

What is a negative or positive impact to a critical area?
An impact to a critical area means the development or activity may or will reduce the biological, hydrological, and/or geological elements - the functions and values - of the underlying critical area system. An impact to a critical area is generally created by a "human induced change in an existing condition of a critical area or its buffer, including, but are not limited to grading, filling, clearing (vegetation), construction, compaction, excavation, or any other activity or use that changes the character of the critical area. Typically an impact is considered negative, but impacts can also have positive and desired effects.

A negative impact is when an activity would, or has potential over time to, degrade the existing condition of a critical area, create a risk from a critical area, or cause damage or alteration to the critical area in a way that is not a desired or necessary outcome of the activity. An encroachment into the critical area or buffer or the type or intensity or a development nearby can have impacts that need to be evaluated and addressed.

A positive impact would be one that improves the condition or function of a critical area. For example, removing noxious weeds and replanting with native vegetation, stabilizing hillsides, removing debris from streams and wetlands, restoring degraded critical areas, and creating habitat for fish and wildlife.

Some activities have low impacts such as passive recreation, bird watching, removal of invasive species, and planting of native vegetation, maintenance and repair of existing structures. Some activities have a more moderate but increasing negative impact, such as an addition to an existing structure, a rockery, utility installation or widen a driveway. Other activities can have a significant and detrimental impact on the critical area systems, such as excavation or filling, commercial or multi-family construction, or a new road, that need to be avoided or mitigated to retain or improve the system functionality. 

Other benefits of critical area regulations
Benefits to the City include protecting property owners from impacts to critical areas with negative outcomes, reduced costs of public infrastructure improvements, reduced maintenance costs of storm water system and repair of streets, access to federal grant and loan programs involving assistance for damage to structure in frequently flooded areas, and eligible for federal disaster assistance and certain federal mitigation grants.

Benefits to property owners may include protect property from damage, increased property value, ability to know what can or cannot be done in a critical area on their property, opportunities for recreation and enjoyment of open space, wildlife and clean air, reduced mortgage insurance, and ability to obtain loans backed by federally sponsored entities.