There was a particularly nice creek restoration completed by Friends of the Hylebos Wetland with Natural Systems Design doing design/build. Cash from federal grants and municipal
water district funds. Cudos to Earthcorps for supporting
volunteer involvement.
(I posted a picture on google earth)
google earth: 5th avenue and emerald street, milton, wa
Its a coho salmon stream, and coho rear for a year or more in channel before going to see. Winter flood refugia and channel complexity are important during this part of their lifecycle. This reach of Hylebos creek was put into a ditch against the valley wall for ag development, with the channel reduced to a sandy bottom flume, but the resulting ag land has since been left to reed canarygrass (Phalaris arundinacea) which has arrested succession to cottonwood, alder, or cedar. Some initial attempts were made to increase channel roughness with small
wood and rock. The result was the creek just jumped channel during high flow, did not have
enough energy to scour the channel, and returned to the unchanged ditch as flow decreased.
The projects was relatively low in cash. They acquired non-marketable logs from a windfall salvage. They didn't import or export materials. They used a municipal track-hoe crew and made one pass down a new 'meander belt' to minimize the impacts of equipment on the site. The equipment operator worked in tandom with a field biologist, who read the lay of the land to create meanders, high spots and low spots, on and off channel, and inserting wood to create in channel complexity, dumping gravel to jump start bed structure--all the while disrupting the Phalaris rhizome mat. I have found that after they get over the culture shock, the biologist/equipment operator teams start having a lot of fun.
Then the creek was diverted back into the modified floodplain. Volunteers were use to pepper the site with willow stakes. The roughened floodplain created a complex of riffles and pools. Gravel began to sort well in the channel. Coho spawned the next year. low spots began collecting fine sediments and were planted with sedge. The willow sprang up to replace the canarygrass. A loose log jam was woven into a downstream willow thicket to keep floating logs from the downstream culverts.
Qualities:
the channel was un-engineered and designed to be dynamic within a naturally scaled range of change (a meander belt).
After careful observation, a single intense intervention resolved the core issues of the site, which is now evolving along a path of increasing natural complexity.
Materials were salvaged and gathered using a
local volunteer and donor network that simultaneously built local stewardship of Hylebos Creek.
The design used an interdisciplinary team that used collaborative on-site design strategies rather than "firm/fixed" bid and build approach.
