Two new projects are set to begin as part of the Heron Habitat Helpers' efforts to restore Kiwanis Ravine, announced HHH co-chair Heidi Carpine at a meeting the group held last week.
The steeply sloped ravine just to the east of Discovery Park is home to the city's largest Great Blue Heron rookery, and one project will involve $76,000 in grants, along with Earth-Corps staffers and contractors who will remove invasive plants and replant the area with native species, she said.
The other project, Carpine said, will use volunteer labor and $12,200 in grants to restore part of the Kiwanis Wildlife Corridor, which leads to West Commodore Way from the ravine.
The two upcoming projects are in addition to an ongoing one at the Kiwanis Ravine Overlook on Ohman Place just off 36th Avenue West. Work on the Ohman Place project is being done by volunteer labor, and it is financed by $10,300 in grant money from Seattle Public Utilities and the King County Natural Resources Stewardship Network.
The corridor
Originally, the group applied for $23,000 in grant money to finance work on around an acre in the corridor, said HHH member Timothy Randle. What they ended up with, instead, was $9,900 from the King County Wild Places in City Spaces Program, along with a later $3,300 booster grant from the same program, he said.
"Because there was less money, we went with a smaller area," Randle said of approximately half an acre of unused Gilman Street right-of-way just south of West Commodore Way. The corridor includes a "social" path through it, but work on the trail has been scaled back to making basic improvements since the grant came in short, he said.
The bulk of the work will involve removing the main invasive plants: Himalayan Blackberries and Japanese and Giant Knotweed. The blackberry plants will be flattened in a one-day project using a Bobcat construction machine, he said. The flattened plants will then be covered with cardboard and roughly 8 inches of wood-chip mulch, Randle said.
The flattening-and-covering approach is preferable to cutting the blackberry bushes down because it will smother the plants and not trigger natural regeneration, according to a project report prepared by Randle.
The knotweed is a bit hardier, and the accepted practice now is to spray them with herbicide, bend the plants over and cover them in wood mulch, according to Randle.
"We're also concerned with creating an attractive nuisance," he said of the restoration work, which will demolish a natural barrier between the corridor and the railroad right-of-way.
To address the concern that children and adults might be tempted to walk onto the tracks from the corridor, a 200-foot length of chain-link fence will be installed temporarily, and thorny native species will be planted to replace the invasive species, Randle explained.
Getting rid of the invasive plants and replacing them with native species is only part of the battle. "We have an issue with watering on this site," he said.
The HHH is looking at three options, Randle said. One is spending $2,000 of the grant money to tap into a water main that runs under the corridor. A second is installing a cistern and filling it with tertiary wastewater. The third is to use water provided by nearby residents in exchange for HHH paying all or part of homeowners' water bills, he said.
The issue is far from resolved, Randle conceded. "But we ultimately need water to maintain the plants for the first couple of years."
Work is scheduled to begin in December and continue through next fall, he said.
The ravine
Work on Kiwanis Ravine itself will also begin next month, but the work has to be restricted during the February-through-August nesting season of the Great Blue Herons. That's because the birds are skittish critters that are easily spooked and might abandon the rookery if they are disturbed, according to wildlife experts.
There's another restriction, according to HHH co-chair Donna Kostka. The slopes are so steep, it would be dangerous for volunteers to work there, she said. Because of that, EarthCorp workers and contractors will be used for the work, she said.
Kostka said funding for the ravine-restoration work will come from two sources: a $37,000 large grant from the Department of Neighborhoods and a $39,000 grant the National Oceanic and Atmospheric Administration made to EarthCorps for the project.
There is a fair amount of invasive plants such as Himalayan Blackberries in the ravine, and the plants will be tackled the same way they will be in the wildlife corridor. But the biggest problem is English Ivy, explained Pieter Bohen from EarthCorps. If left unchecked, the ivy will kill trees in 20 years, he said.
The ivy will be removed first from the trees because the plant starts to seed once it reaches that stage, Bohen said. "On the ground, you physically roll it up using a bunch of people. Then you put it on cardboard and let it compost on site."
Kostka noted that English Ivy is also growing in the back yards of many homes surrounding Kiwanis Ravine, which means the plant could eventually establish a new foothold in the ravine. "We certainly hope to motivate neighbors to work in their backyards," she said. But Kostka also wondered about liability issues if vol-unteers help out on private property.
It's a common situation, according to Bohen. "What we typically do is sign an agreement with the homeowners" he said of an arrangement in which the homeowners are charged $450 to have EarthCorps supervise a vol-unteer group. That way, the volunteers are covered by the organization's insurance, Bohen said.
There is another downside to the invasive plants in the ravine.
"Most of the invasive species, they don't contribute very much to slope stability," said Garrett Jackson, a Magnolia geologist who will be working with EarthCorps on the project.
The roots are too shallow, he explained. Stabilizing the slopes will also help maintain Wolfe Creek, he said of the meandering stream at the bottom of the ravine.
But saving the creek is only part of a larger picture.
"Ultimately, the big reason [for the restoration project] is the sustain- ability of the heron rookery," Jackson said.
