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Cedar Grove Road Natural Area is 2.55 acres in size and consists of four parcels. The site is located at the northeast corner of the intersection of State Route 169 (Maple Valley-Black Diamond Road) and Cedar Grove Road approximately four miles southeast of Renton and three miles north of Maple Valley. The Cedar River forms the north and east boundaries of the site. The Cedar River Trail runs along the western side of the property.

This reach of the Cedar River used to be extensively braided, but the channel location is relatively stable at this time due to a high number of revetments and locations where it flows against the valley wall. Cedar Grove Road Natural Area is located directly across the river from the right bank Rainbow Bend levee, and immediately upstream from the left bank Cedar Trail levee. Both the Cedar Grove Road Natural Area and the entire Rainbow Bend peninsula across the river lie completely within the 100-year floodplain; the floodway (the area of deepest and fastest flows) extends across much of these areas as well.

Cedar Grove Road Natural Area picture
The eastern part of the property supports typical riparian forest along the Cedar River: black cottonwood and red alder overstory, with mostly native species in the understory (thimbleberry, salmonberry, willows). A sparse conifer overstory and older bigleaf maples exist on the western portion of the site. Japanese knotweed occurs along the riverbank. The central and western portions of the site were hydroseeded and replanted during project work. The large gravels in this part of the river are suitable for spawning by sockeye, Chinook, and coho salmon, as well as rainbow, steelhead, and cutthroat trout. Passive recreational uses at the site include walking, picnicking, and nature observation. The eastern portion of the Cedar Grove Road Natural Area is used by rafters as a take-out. An informal trail that leads from Cedar Grove Road east to the Cedar River is used regularly by visitors. Smaller informal trails allow users more occasional access to other portions of the site. In the central portion of the site is a grassy clearing in which trees have been re-planted, and woody debris has been installed for wildlife habitat. This grassy part of the site can provide an appropriate area for public use as long as that use does not impact the tree plantings in this area. In other portions of the site, dense shrub vegetation may limit access. The site is readily accessible from the adjacent Cedar River Trail. There is no parking at the site (although parking occurs along the side of the road).

The Cedar Grove Road Natural Area Site Management Guidelines are available in Adobe Acrobat format. For help using Acrobat files, please visit our Acrobat help page.

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Cedar Grove Road Natural Area Site Management Guidelines