|COOPERATIVE CONSERVATION CASE STUDY|
|Dry Creek Quarry Restoration|
|Restoration of a Retired Gravel Mine to Natural Conditions|
|Project Summary: Since 2004, Sequoia Riverlands Trust has been restoring natural stream flows, recontouring disturbed areas, seeding native grasses and planting oak and sycamore trees at this former gravel mine.|
|Nathan Higgins, Sequoia Riverlands Trust|
For more than a decade, the 152-acre dry creek quarry had been used for aggregate mining, supplying gravel and crushed rock for construction. During mining operations, the following changes occured to the landscape:
- Numerous mature sycamores and valley oaks felled
- Naturally meandering Dry Creek artificially channeled with earthen barriers
- Deeper channels caused stream bank erosion and altered the delicate hydrology on which healthy sycamore woodlands depend
- Artificial lake created by digging a hard-rock mining pit
- Mining debris stock piled throughout the site
The quarry, located west of the entrance to Sequoia and Kings Canyon National Parks, cuts across the lower reach of Dry Creek. This area, widely popular for its spring wildflower shows, is home to one of the largest remaining sycamore alluvial woodland communities in the world. This rare and unusual streamside community provides critical habitat for resident and migratory birds, and the Dry Creek landscape supports native species such as great blue heron, bald eagle and herds of mule deer.
Working with our partner, The Nature Conservancy, as well as scientific experts from federal agencies and universities, Sequoia Riverlands Trust developed a restoration plan for the site, which when completed, will ensure the health of the Dry Creek sycamore alluvial woodland, enhance important wildlife corridors and provide the public with a place to enjoy natural river environments while learning how retired gravel mines can again provide wildlife habitat, scenic beauty and an opportunity for community stewardship.
Examples of Key Partners
Sequoia Riverlands Trust, Natural Resources Conservation Service, Preserving Wild California program of the Resources Legacy Fund Foundation, The Nature Conservancy, National Park Service--Sequoia and Kings Canyon National Parks, UC Davis, UC Berkeley, Cal Poly Pomona, California Portland Cement Company, local landowners, members and volunteers of Sequoia Riverlands Trust
Results and Accomplishments
For years, residents and visitors traveling on Dry Creek Drive witnessed the effects of gravel mining at the former quarry with altered views of the land and creek. Now, those moseying down this County-designated scenic drive will have a clear view of the rare sycamore alluvial woodland we seek to restore.
After receiving the quarry donation from California Portland Cement Company in early 2004, contractors removed artificial barriers that prevented natural stream flows during prior gravel mining and recontoured spoils piles in the former gravel processing area and along the roadway. Our goal was to allow future high water to spread throughout the floodplain in braided channels, creating conditions suitable for the establishment of California sycamores. With sustained rains this past winter, Dry Creek rose five feet, established new channels and deposited lots of new sediment in between those channels.
With the ground bare and exposed from rock and soil re-contouring, the potential for unstable soils and resulting erosion was high. We immediately seeded 10 acres with a mix of native grass and forbs. Now, several months later, natives flourished so well that we can collect local seed to expand the revegetation efforts into other areas of the restoration site. We will continue to manage for native plant communities as this project continues.
We work to replace the mature sycamores and valley and blue oaks felled during mining operations by collecting and germinating acorns and sycamore seeds. With the rain on our side, we distributed sycamore seed in the new sandbar deposits created during flooding, planted 100 valley and blue oaks and germinated 400 sycamores for planting this fall. In addition, over 100 volunteer sycamores established themselves since mining ceased.
The Cal Poly Pomona 606 Studio, a masters-level class for landscape design, chose Dry Creek Preserve as one of four projects taken on by the Studio this year. We asked them to work at several design levels: watershed, preserve (for both Dry Creek and Homer Ranch, three miles up the road) and individual projects, like a concept design for visitor facilities in the footprint of the old gravel processing area.
When completed, this project will be the first example of an aggregate mine reclamation in Tulare County. The partners involved plan to provide a model for ecologically-based restoration of retired gravel mines. The restored landscape will also be a welcomed change for members of the local community, who have lived for a dozen years with the inevitable inconveniences of an industrial operation in their neighborhood, changes to the Dry Creek landscape and with a visual intrusion on what is a designated scenic drive in Tulare County.
Once accomplished, this project will provide the first example of an ecologically-based aggregate mine reclamation in Tulare County. In the future, the preserve will provide the public with a place to enjoy natural river environments while learning how retired gravel mines can again provide wildlife habitat, scenic beauty and an opportunity for community stewardship.