18E.40.060 Buffer Requirements | Pierce County Code

18E.40.060 Buffer Requirements.

A. Buffer Delineation. Buffers shall be required as set forth for each habitat type. The required buffers shall be delineated, both on a site plan or plat and on the property, prior to approval of any regulated activity.

a. Riparian areas (rivers, streams, and creeks), lakes, and ponds shall be managed through the use of buffers.

b. The required riparian buffer width is measured from the edge of the channel migration zone (CMZ), where identified, or the ordinary high water mark, whichever is greater. The criteria for determining the locations of the CMZ is provided in Chapter 18E.70 PCC.

c. The required lake or pond buffer width is measured from the edge of the ordinary high water mark (OHWM).

d. The required buffer shall be extended to include any adjacent regulated wetland(s), landslide hazard areas and/or erosion hazard areas and required buffers. (See Figures 18E.40-4 and 18E.40-5 in Chapter 18E.120 PCC.)

a. Marine shoreline critical salmon habitat shall be managed through the use of buffers. Refer to Table 18E.40.060-1 for the associated buffer requirements.

b. The required buffer width is measured from the edge of the ordinary high water mark (OHWM).

c. The required buffer shall be extended to include any adjacent regulated wetland(s), landslide hazard areas and/or erosion hazard areas and required buffers. (See Figures 18E.40-4 and 18E.40-5 in Chapter 18E.120 PCC.)

Table 18E.40.060-1. Fish and Wildlife Habitat Conservation Area Buffer Requirements
Water Type (1)	Water Body Criteria	Buffer Width (2,4)
Type S1	Marine waters designated as Marine Shoreline Critical Salmon Habitat	100 feet landward from the OHWM
Type F1	All segments of natural waters within the bankfull widths of defined channels or within lakes, ponds, or impoundments which provide habitat for or support any portion of the lifecycle of a critical fish species (3). Waters that are diverted for use by federal, state, tribal, or private fish hatcheries shall be considered to be Type F1 waters upstream from the point of diversion for 1,500 feet and tributaries if highly significant for protection of downstream water quality.	150 feet landward from the OHWM
Type F2	Type F1 water adjacent to a landslide hazard area as set forth in Chapter 18E.80 PCC.	150 feet landward from the OHWM or the minimum buffer distance required in Chapter 18E.80 PCC, whichever is greatest
Type N1	Perennial or seasonal non-fish bearing (3) natural waters within the bankfull widths of defined channels that are not Type F1 or F2 waters but are located within ¼ mile of the confluence with a Type F1 or F2 water.	115 feet landward from the OHWM
Type N2	Perennial or seasonal non-fish bearing (3) natural waters within bankfull width of defined channels that are not Type F1 or F2 waters and are either located more than ¼ mile upstream from the confluence with a Type F1 or F2 water or are not connected to a Type F1 or F2 water.	65 feet landward from the OHWM
Type N3	Lakes or ponds that do not support any critical fish species (3)	35 feet landward from the OHWM
(1) Water types are mapped in the Pierce County Critical Areas Atlas: Fish and Wildlife Habitat Areas-Stream Typing Maps and Fish and Wildlife Habitat Areas-Critical Fish Presence Maps. (2) There may be regulated wetlands associated with water types and which may have a required buffer greater than those listed in Table 18E.40.060-1, e.g., a lake with a 35-foot buffer requirement may have associated wetlands with 25-300 foot buffers. (3) Fish species are those identified in PCC 18E.40.020. (4) Lake Tapps and Spanaway Lake are not subject to the buffering requirements shown above in Table 18E.40.060-1.

C. Buffers for Other Critical Habitat Areas. Appropriate buffers for critical habitat areas not listed in Table 18E.40.060-1 shall be determined on a case-by-case basis, based upon the needs of specific species or habitat area of study. The Department will coordinate with WDFW in these instances to determine an appropriate buffer width and, when available, shall rely upon buffer widths specified in WDFW Priority Habitats and Species management recommendations.

a. Development on shorelines is subject to the applicable buffer requirements of Table 18E.40.060-1 and Title 18S PCC, Development Policies and Regulations – Shorelines. Where these buffers differ from the applicable requirement of this Title, the most restrictive buffer width applies.

b. Standard shoreline buffers listed in Table 18S.30.030-2 are based on the Shoreline Environment Designation.

c. Shoreline buffers are measured from the ordinary high water mark (OHWM), except that for Lake Tapps Reservoir, the setback shall be measured from the full pool elevation of 543 feet (equivalent to water level 543 msl as measured at the USGS Gage 12101000).

1. Setbacks. An applicant wishing to reduce a setback shall pursue a variance pursuant to PCC 18E.20.060, except that reductions to the standard shoreline buffers of Table 18S.30.030-2 shall be reviewed pursuant to Title 18S PCC, Development Policies and Regulations – Shorelines.

a. Where used in this Section, "developed lot" shall mean a lot with a residential dwelling and a maintained yard.

b. Regulated activities are to be kept out of the standard buffer where feasible, as required by the impact avoidance requirements of PCC 18E.40.050, Mitigation Requirements.

c. Where it is not feasible to stay out of the standard buffer, with the exception of Forest Practices, the standard buffer widths of subsection B of this Section may be decreased through the following buffer averaging or buffer reduction allowances:

(1) Buffer Averaging. Buffer width averaging may be proposed through submittal of a Habitat Assessment Study or Report. Buffer width averaging, which allows certain portions of the buffer to be decreased if other portions are increased, shall be allowed only when the applicant demonstrates all of the following:

(a) The decrease in buffer width is minimized by limiting the degree or magnitude of the regulated activity.

(b) Buffer averaging will not adversely impact the water body.

(c) Buffer averaging is consistent with other buffer requirements set forth under this Title (e.g., wetlands, critical fish and wildlife species and habitats, landslide hazard areas, etc.).

(d) Buffer averaging will not increase the risk of slope failure or downslope stormwater drainage impacts.

(e) The total buffer area after averaging is no less than the buffer area prior to the averaging. (Refer to Figure 18E.40-6 in Chapter 18E.120 PCC.)

(f) The buffer meets the vegetation coverage requirements of subsection G.1.a of this Section, or the applicant enhances the buffer as allowed in PCC 18E.40.050 B., Mitigation, in order to meet the coverage requirements.

(g) The averaging is accomplished within the project boundaries or through an off-site conservation easement or tract (or other acceptable protective mechanism) approved by the Department.

(h) The buffer meets the applicable requirements of PCC 18E.40.060 D.*

* Code Revisor's Note: The reference to PCC 18E.40.060 D. above is incorrect. The correct cite should be PCC 18E.40.060 G.

(2) Buffer Reduction. Buffer width reduction, which allows for all or portions of the buffer to be reduced without an equal increase in other areas of the buffer, may be allowed when the applicant demonstrates all of the following:

(a) Buffer reduction is unavoidable.

(b) Buffer reduction has been minimized by limiting the degree or magnitude of the regulated activity.

(c) Buffer reduction is consistent with other buffer requirements set forth under this Title (e.g., wetlands, critical fish and wildlife species and habitats, landslide hazard areas, etc.).

(d) Buffer reduction will not adversely impact the water body.

(e) The buffer width will not be reduced more than 25 percent below the provisions of subsection B of this Section

(f) The buffer meets the requirements of subsection G of this Section, or

(g) The buffer has less than 15 percent slopes.

E. Buffer Modification Recognizing Adjacent Development, Lakes and Shorelines. Within an undeveloped lot, buffer modifications may be used to reduce a lake, marine or freshwater shoreline buffer when a legally established principal residence exists within 100 feet of the undeveloped lot on one or both adjacent waterfront lot(s), calculated as follows:

1. Modification to the standard buffer shall be calculated by adding the existing waterfront setback/buffer of the adjacent lots together and dividing that figure by two.

2. In the case of a corner lot or when one adjacent lot is vacant, the modifications shall be calculated by adding the home setback of the adjacent developed lot to the standard (unmodified) buffer requirement and dividing that figure by two.

3. The setback/buffer shall not be reduced to less than 50 feet.

4. This modification does not apply where the criteria of subsection F of this Section, Buffer Width Increases, apply or when the adjacent residence(s) was built with reduced setbacks pursuant to a setback or buffer variance approval.

F. Buffer Width Increases. The Department may require an increased buffer width when a larger buffer is necessary, based on specific site conditions and project features, to protect habitat area functions and values. This determination shall be reasonably related to protection of the functions and values of the regulated habitat area. A determination that a larger buffer is needed shall be based on the following factors:

1. A larger buffer is necessary to maintain viable populations of existing species or protect the existing functions of habitat areas identified in PCC 18E.40.020.

2. The adjacent land has minimal vegetative cover. A larger buffer may not be needed when vegetation issues can be addressed through the submittal of a planting plan as defined in PCC 18E.40.050 B.

3. The adjacent land has slopes greater than 20 percent.

4. The habitat area is in an area of high tree blow down potential. In these cases, the habitat area may be expanded an additional 50 feet on the windward side.

a. In order to ensure no net loss of regulated species, habitat, or shoreline function from new development or the expansion of existing development, buffers should be adequately vegetated. For purposes of this Section, "adequately vegetated" generally means that the buffer contains a variety of species and growth forms (e.g., groundcover, shrub, sapling, tree) at a density and variety sufficient to protect the functions and values of the regulated area from impacts associated with the regulated activities.

b. Buffer vegetation should consist of native species. However, a buffer that contains well established non-native vegetation may also be deemed "well vegetated."

c. When determining whether a buffer is adequately vegetated, staff shall take into account not only the condition of the buffer at the time of any applicable review, but also its likely future condition once it is protected and succession is allowed to occur.

d. For purposes of this Section, an undeveloped lot is one lacking a principal residential structure and maintained yard. Existing lawn will not qualify as vegetation for purposes of meeting the required coverage.

H. Protection of Significant Trees within the Buffer. If buffer width averaging or reduction is utilized or buffers are otherwise reduced through a variance process and significant trees as defined in Table 18J.15.030-1 are identified on the outer edge of the reduced buffer such that their drip line extends beyond the buffer edge, the following tree protection requirements must be followed:

1. A tree protection area shall be designed to protect each tree or tree stand during site development and construction. Tree protection areas may vary widely in shape, but must extend a minimum of 5 feet beyond the existing tree canopy area along the outer edge of the dripline of the tree(s), unless otherwise approved by the Department.

2. Tree protection areas shall be added and clearly labeled on all applicable site development and construction drawings, submitted to the Department.

3. Temporary construction fencing at least 30 inches tall shall be erected around the perimeter of the tree protection areas prior to the initiation of any clearing or grading. The fencing shall be posted with signage clearly identifying the tree protection area. The fencing shall remain in place through site development and construction.

4. No clearing, grading, filling or other development activities shall occur within the tree protection area, except where approved in advance by the Department and shown on the approved plans for the proposal.

5. No vehicles, construction materials, fuel, or other materials shall be placed in tree protection areas. Movement of any vehicles within tree protection areas shall be prohibited.

6. No nails, rope, cable, signs, or fencing shall be attached to any tree proposed for retention.

7. The Department may approve the use of alternate tree protection techniques if an equal or greater level of protection will be provided.