85 RESOURCE LANDS AND CRITICAL AREAS
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Wetland Category | Description |
|---|---|
Category I | Category I wetlands are: (1) alkali wetlands; (2) wetlands of high conservation value that are identified by scientists of the Washington Natural Heritage Program/DNR; (3) bogs and calcareous fens; (4) mature and old-growth forested wetlands over 1/4 acre with slow-growing trees; (5) forests with stands of aspen; and (6) wetlands that perform many functions very well (scores between 22 and 27 points). These wetlands are those that (1) represent a unique or rare wetland type; or (2) are more sensitive to disturbance than most wetlands; or (3) are relatively undisturbed and contain ecological attributes that are impossible to replace within a human lifetime; or (4) provide a high level of function. |
Category II | Category II wetlands are: (1) forested wetlands in the floodplains of rivers; (2) mature and old-growth forested wetlands over 1/4 acre with fast-growing trees; (3) vernal pools; and (4) wetlands that perform functions well (scores between 19 and 21 points). These wetlands are difficult, though not impossible, to replace, and provide high levels of some functions. These wetlands occur more commonly than Category I wetlands but still need a relatively high level of protection. |
Category III | Category III wetlands have a moderate level of functions (scores between 16 and 18 points). These wetlands can be often adequately replaced with a well-planned mitigation project. Wetlands scoring between 16 and 18 points generally have been disturbed in some ways and are often less diverse or more isolated from other natural resources in the landscape than Category II wetlands. |
Category IV | Category IV wetlands have the lowest level of functions (scores less than 16 points) and are often heavily disturbed. These are wetlands that we should be able to replace, and in some cases be able to improve. However, experience has shown that replacement cannot be guaranteed in any specific case. These wetlands may provide some important functions and also need to be protected. |
Wetland Category | Setback |
|---|---|
Category I | 250 feet |
Category II | 200 feet |
Category III | 150 feet |
Category IV | 50 feet |
Wetland Category | Mitigation Ratio |
|---|---|
Category I | 6:1 |
Category II | 3:1 |
Category III | 2:1 |
Category IV | 1.5:1 |