Trying to figure out how close you can build to the creek, stream or other body of water on your property? As a year-round water body on your property it is likely classified as Salmon bearing or a Salmon habitat even if you’ve never seen fish in it.
The state identifies bodies of water as two types, type S or F. Type S water bodies are large bodies of water that are inventoried by the state; bodies of water that are 20 acres in size or larger, have a flow rate of 20 cubic feet per second or are marine shorelines. To make it simple – these are primarily lakes, rivers & saltwater. Type F water bodies are described as those that are not type S and contain fish habitat. If your water body in question is neither of these then it is either a wetland (critical area or environmentally sensitive area) or considered “unclassified”. The tricky part is that typically an unclassified body of water requires a site visit by the county or a hired biologist to determine if it should have a classification in order to determine what your buffer should be.
A type F creek in King County, for example, has a 165′ buffer plus the appropriate setback deemed by the zoning area you fall into. Often homes are built prior to a classification being assigned and recognized by the county. In this case, the existing home is exempt as it was originally permitted. You are allowed to add an additional 1,000 square feet to the existing residence without mitigation. If, however, your project is larger than 1,000 square feet then you will be required to mitigate at a 1:1 ratio. This typically means that if 1,000 square feet of new structure is proposed, 1,000 square feet of approved planting elsewhere within the buffer would be required.
The good news is that a lot can be done to an existing residence with 1,000 square feet, especially with a talented architect! Take a look at the upcoming pictures of the finished May Valley project that utilized it’s 1,000 square foot addition allowance on a cottage that was tiny to begin with. Designed by Jim Merrill of Merrill Design, Inc. and built by Mehl Homes, Inc. Here is a sneak peek we took during construction.