During phase 1 of the KCWQIP we found the lower reaches of Kimball Creek to be almost uniformly dominated by blackberry in the riparian zone. This has limited the recruitment of new vegetation. Many of the older riparian trees have senesced, resulting in a lack of riparian shading and excessive solar radiation reaching the stream, contributing to impaired water quality. A number of sources list Kimball Creek as having impaired water quality, including the Snoqualmie Watershed Water Quality Synthesis Report and the State's 303(d) list of impaired waterbodies. Kimball Creek is impaired for temperature and dissolved oxygen; the former directly impacts the latter. Establishing native vegetation along the creek will help to provide shade and prevent additional warming and the corresponding decrease in D.O.

Legacy effects of past dredging in Kimball Creek currently impair ecosystem processes. Over-steepened banks result in a lack of high-flow refugia for aquatic organisms, and the vertical banks also periodically slump into the creek, delivering fine sediment to the waterway. We propose to echo the work of re-grading the creek bank to a more gradual slope that was permitted and accomplished in Phase 2. This step also helps ensure effective removal of invasive plants and successful establishment of new native vegetation.

The Phase 3 site proposed here is across the creek from Phase 2. Landowners seeing the work accomplished in Phase 2 expressed interest in undertaking something similar on their property, which led to this proposed Phase 3; discussion and planning for Phase 4 are similarly under way. We will re-grade and establish a 35-foot native riparian plant buffer on 1100 feet of the north bank of Kimball Creek. We will maintain the site to ensure plant survival and invasive vegetation exclusion for a minimum of three (3) years. This will include watering, weeding, herbivory management, and plant replacement if necessary. Some economy of scale is expected in regard to maintenance since we are already maintaining Phase 2 which is directly across the creek from the Phase 3 site proposed here.