Garden Lake Riparian Restoration Project
Garden Lake was identified as a priority area as it had seen the excavation of gravel for the construction of 1-5 creating a series of ponds in line with Hill Creek but was now in public ownership. Blackberry, Scot’s broom and English ivy were preventing the integrity and reestablishment of habitats at the park.
SOLUTION
Invasive species were removed. We used remnants of reference ecosystems on site to guide our planting choices. A diversity of species were planted, not just trees. City of Creswell allocated staff time to water the trees and shrubs in the park
RESULTS
Infestations of Scot’s broom, English ivy, and Blackberry were all significantly reduced in scale and extent on the 11 acres of project area. Invasive plant removal and the planting of native trees/shrubs improved eleven acres of riparian habitat. Watering happened efficiently and seemingly cost-effective, and plant survival was far improved thanks to this effort.
Forest and Wetland Enhancement
Now robust with wildlife and outdoor opportunities within walking distance of Creswell, Garden Lake Park was just an old gravel pit covered in blackberries alongside Interstate 5 less than 12 years ago. During the construction of I-5, gravel was mined from this site creating a series of ponds. Improvements at the 34 acre Garden Lake Park were initially spearheaded by the late Mayor Ron Petitti and the Creswell High School Key Club liaison Anne O’Connell and her students. Then in 2006, the Coast Fork Willamette Watershed Council secured funds to conduct a large-scale habitat enhancement project. An Oregon Watershed Enhancement Board (OWEB) grant provided funding for 3 years of manual and mechanical removal of Himalayan blackberry, English ivy and Scot’s broom and the reestablishment of native trees and shrubs across 11 acres of forests, ponds, and wetland habitats in this city park.
The Coast Fork Willamette Watershed Council intentionally chose to use a non-chemical weed removal method on this first large-scale vegetation enhancement project which included treatment of Himalayan blackberry, English ivy, and Scot’s broom over 11 acres. This required the use of highly skilled crews, primarily with Walama Restoration Project, who cut and then grubbed out the roots in both open areas and within the poison oak-infested understory. We repeated treatment over a minimum of two years in each area then returned to conduct maintenance with volunteers. After this site preparation, we planted trees and other native species in key locations of Garden Lake Park. This hands-on approach to restoration minimized impacts to the understory vegetation, allowing natural recovery after invasives were removed especially in areas of the park that contained mature native species mixed with non-natives. Invasive removal occurred in the fall months, planting of native species took place in the late winter, and the plantings were watered in the summer. The project plan was tailored to the various distinct sections of the project, including stream areas, a peninsula, and a central area.
Native tree and shrub species planted to enhance habitats at Garden Lake Park include black cottonwood, big-leaf maple, Oregon ash, Oregon white oak, red alder, willows, osoberry (Indian plum), Oregon grape, red-osier dogwood, snowberry, Douglas spirea, large-leaf lupine, and slough sedge. The park also features good stands of these native plants common camas, cow parsnip, stinging nettle, and the infamous, but native, poison oak! Photopoint monitoring of the completed planting areas will be used to document project success through 2014.
Wildlife species that benefit from restoration at Garden Lake Park include cutthroat trout, Western pond turtle, bald eagle, migrant songbirds, osprey, great blue heron, great egrets, American coot, double-crested cormorants, Canada geese, ducks, snakes, raccoons, possum, skunk, beaver, and otter.
10 Years of Stewardship
Improving this valuable open space became an opportunity for students to become stewards of this park and their community. Trail improvement and habitat maintenance occurs annually with coordination by the Creswell RARE planner and the Creswell High School with support from volunteers from businesses, individuals, and the Coast Fork Willamette Watershed Council. After the loss of Mayor Ron Petitti in 2008, many community organizations and leaders came together to honor the inclusive community spirit of the Mayor with the construction of an educational pavilion which was completed in 2009. This park improvement and watershed signage provided a great platform for a student-focused Earth Day event which began in 2010 as the next step in the evolution of this community effort. Further interest resulted in the construction of two foot bridges which connect the park to the Emerald Valley development by the Ford Family Leadership class. After 10 years of ongoing volunteer-based habitat and trail maintenance at this Creswell site, it is safe to say that the Coast Fork’s effort to secure funding for habitat restoration in 2006 was instrumental in building the momentum necessary for this ongoing community action on this site.
Hydrology of Garden Lake
The three ponds at Garden Lake Park are within the historic floodplain of the Coast Fork Willamette River. Significant gravel deposits found there were mined for the construction of Interstate 5 which formed the ponds. The park is 2 miles upstream from the Hill Creek confluence with the lower Coast Fork Willamette River. I-5 forms the western boundary of the park and the Emerald Valley housing development forms the eastern park boundary. The northern boundary of the park is shared with two small farms. The southern boundary of the park includes the Hill Creek riparian corridor.
Prior to the construction of I-5, significant alterations were made to Hill Creek, as the flow was directed out of the natural channel and made to intersect with a system of irrigation canals before entering Creswell city limits. The modern Hill Creek is fed by the natural channel when flows are allowed down it (there is full control of this creek at the top of the Davisson Road diversion structure), by flow augmentation of the irrigation canal (that connects to the mainstem Coast Fork), as well as by storm water runoff (that passes under I-5 and into the park), and precipitation.
Water Quality Concerns in Hill Creek
Currently, there are water quality issues in the ponds at Garden Lake Park. Due to community concerns about late-summer algae blooms, warm temperatures, and storm water runoff entering the ponds, the Coast Fork Willamette Watershed Council will conduct an evaluation of pond depths, conditions, and water quality by conducting monthly sampling of several sites in 2012. It is our intention is to make a preliminary technical evaluation of possible limiting factors to the aquatic habitat to the City of Creswell and other partners by early 2013. This technical evaluation is necessary in order to begin a dialogue about possible restoration actions that would address these possible water quality problems. There are potential solutions to these problems that could be installed at Garden Lake Park or within the Hill Creek system. Landowners within the Hill Creek system who are interested in irrigation efficiency, fencing livestock away from sensitive wetlands or streams, obtaining help with managing their septic systems, or restoring stream or wetland habitats are encouraged to contact the Watershed Council.
Hill Creek/Garden Lake Issues:
- The appearance of algae in late summer may be influenced by:
- nutrient runoff into Hill Creek or historic deposits in the pond (nutrient sources range from fertilizer, manure, to septic overflows)
- reduced flow from natural sources due to legal and illegal water use upstream, as well as loss of wetlands which provide late-season release and the recharge of springs
- increased temperatures in the Hill Creek system due to a loss of streamside (riparian) vegetation and loss of wetlands
- A full fish passage barrier at Bald Knob mill due to failure of the historic dam at that site
Technical Information
- Lower Coast Fork Watershed Assessment 2005
- City of Creswell Parks and Open Space Master Plan
Links
- City of Creswell Annual Earth Day Celebration and Earth Day 2011
- City of Creswell Park Facilities
- “Planning for Garden Lake Park Science Education Pavillion Project Proceeding” by Helen Hollyer of The Creswell Chronicle. Published January 21, 2009.
- “Volunteers Enjoy Spring Day While Building Garden Lake Park Trail” by Helen Hollyer of The Creswell Chronicle.
- “Garden Lake Park Foot Bridge Almost Finished” by Helen Hollyer of The Creswell Chronicle. Published September 20, 2010
- “Earth Day Event in Creswell” by Wes Johnson, KVAL News. Published April 13, 2011
Project Partners
City of Creswell
Creswell School District
Walama Restoration Project
Friends of Garden Lake Park
Oregon Department of Fish and Wildlife (ODFW)
Oregon Watershed Enhancement Board (OWEB)
Oregon Parks and Recreation Department (OPRD)
The Williams Company
Emerald People’s Utility District (EPUD)
GeoResources
Creswell Boy Scouts and Eagle Scouts
