by Kammy Kern-Korot, Senior Conservationist
The District’s riparianRiparian areas The land alongside a stream, creek, river, or floodplain restoration program has been quietly restoring rural streamside areas for the past 18 years. What began as a partnership with our federal, state and local conservation partners has grown into a self-sufficient program, now fully funded by the District. The program is lean, but mean; we have a modest budget and get a lot done, focusing on sub-watershedswatershed an area of land that channels rainfall, snowmelt, and runoff into a common body of water, such as a nearby lake or river. Multiple streams can be part of the same watershed area, such as the Tryon Creek Watershed which is fed by Oak Creek, Park Creek, Falling Creek, and others. of greatest interest.
Riparian Restoration by the Numbers
This past year, we enhanced more than 30 acres of riparian habitat at 18 actively managed sites, including planting 3,500 new trees and shrubs along approximately 1,065 feet of stream.
With an annual budget of just about $35,000 in District funds, and often supplemented by small grants, we have developed a cumulative total of 64 projects, along more than 23,000 feet, or 4.3 miles of stream banks (or other shorelines). Since the program’s inception, staff has installed 206,000 plants and 275 pounds of native grass and wildflower seed, and maintained most projects for multiple years. The average age of our projects is 10 years, since we like to steward the sites long enough for the native plants to establish and the habitat to be healthy enough to thrive on its own. Project size ranges from ¼ acre to >8 acres, with the average site size being 1.5 acres.
New Projects in Priority Watersheds
Our priority rural sub-watersheds have been McCarthy Creek, which is designated “Essential salmonid habitat” by Oregon Dept. of Fish and Wildlife; Abbey Creek; Rock Creek; and Sauvie Island/the Multnomah Channel.
We were delighted to add new projects in Crabapple Creek and Rock Creek this year. The Crabapple Creek project is in partnership with Wildwood Golf Course and the Lower Columbia Estuary Partnership (LCEP) and is supported by an OWEB small grant and district funds.
The Rock Creek project was a real community effort, with the landowners’ neighbors and the district chipping in labor and materials to harvest live willow cuttings and install more than 500 plants. Twenty-three volunteers planted along 150 feet of stream and created a new ~300-foot-long native-plant-hedgerow.
The Benefits of Riparian Investment
The District invests in riparian habitats because of the widely recognized ecological importance of these areas and the bang for the buck we get from restoring them. Our projects include a diversity of native trees, shrubs, and sometimes grasses and wildflowers; a typical project has 15 or more native woody species planted. Among the many advantages and beneficiaries of riparian restoration are:
Wildlife
- Riparian areasRiparian areas The land alongside a stream, creek, river, or floodplain provide food, water, cover & nesting for birds, mammals / bats, amphibians and fish; 87% of western Oregon’s 414 known wildlife species use riparian ecosystems extensively
- Pollinators/insects
- Wildlife movement and gene pool corridorsCorridors Wildlife corridor: a stretch of habitat that connects natural areas separated by human land use
Water quality & soil conservation
- Shade vs. high water temperatures (streams with intact riparian forest are cooler; Miller Creek in the graph below is an example)
- Bank stability vs. erosion
- Nutrient uptake (The plants we install help utilize any excess fertilizer or nutrients from animal waste, for example, before it enters a water body)
- Filtration vs. turbidity and sedimentationSedimentation Fine soil particles that are washed into streams collect at the bottom and make water cloudy
- Cost-effective for water quality
Carbon sequestration
- Riparian forests keep carbon in wood and the soil rather than in the atmosphere, where it contributes to climate change / rising temperatures across the globe
- The 19.3 acres at 2 of our oldest riparian restoration projects together stored a total 369 tons (!) of carbon since planting; that’s equivalent to more than 134,000 gallons of gasoline.
- Read more about the study that calculated those results at our blog.
Refuge from heat / climate change
- Enter a shaded streamside area in summer and note how much cooler it is. Air temperatures can increase as much as 18”F are you move away from a stream.
For more information on all the wonderful aspects of riparian restoration and what you can do, see our Streams & Wetlands page.