Report on the Mount Diablo Creek Upper Watershed Tour
July 16, 2005
By Jessica Hamburger, Contra Costa Resource Conservation District
Attendees: Lisa Anich and Mary Malko, Friends of Mount Diablo Creek; Art Bonwell, Save Mount Diablo; Jessica Hamburger, CCRCD; Laura Hoffmeister, City of Clayton/City of Concord; Shwinn Hsueh, Concord resident; Arlene Kikkawa-Nielsen, Clayton Library; Nancy Stein, Contra Costa County Public Works Department; Cindy Welles, Clyde Civic Improvement Association.
Handouts: Agenda and driving directions, liability waiver form, City of Clayton trail map, County Public Works Department watershed brochure and erosion control guide for residents.
The goals of this event were to enable Planning Group members to become familiar with part of the upper watershed by observing land uses and creek and riparian conditions and to provide an opportunity for members to get to know each other in an informal setting. Members who were unable to attend are encouraged to follow the attached driving directions on their own or to contact the watershed coordinator for assistance in forming additional groups to take the tour together. In addition, information on land uses and creek and riparian conditions in the watershed will be presented by the Natural Heritage Institute at the August 4 meeting.
The group assembled at the RCD to review the map, agenda and safety information before heading out on the tour. We visited Donner Creek and Peacock Creek, two of Mount Diablo Creek’s main tributaries, and two sites on the main stem of Mount Diablo Creek. Our observations and comments are recorded below.
1. Donner Creek in Mount Diablo State Park, end of Regency Drive
Being careful to avoid a known rattlesnake den on the steep path at the end the road, we descended to the trail along the fire road on the right side of Regency Drive. We observed a large ground squirrel excavation and Laura Hoffmeister described the City of Clayton’s efforts to control ground squirrel populations. Lisa Anich pointed out the water quality monitoring site on Donner Creek where Friends of Mount Diablo Creek has been measuring water and air temperature and dissolved oxygen and sampling for bacteria.
We observed the landscape in the State Park, noting the riparian area by the creek and the adjacent oak woodlands, and the chaparral areas further up the canyon. We could hear birds, and observed a lizard and some quail running through the grass. We noticed a disked strip of land that serves as a fire break and learned about other types of fire breaks that can be created by mowing instead of disking. We observed signs of erosion caused by water flowing off the road into the creek, exposing the roots of a nearby oak tree and discussed efforts by the local office of the USDA Natural Resource Conservation Service to promote good management of rural roads. Art Bonwell told us that we were walking on one of the first areas that Save Mount Diablo helped preserve in the 1970s, a roughly 1000-acre parcel including Donner Canyon and part of Mitchell Canyon that was previously owned by the Murchio family.
We also observed conditions in the creek. The water was clear, the bottom of the creek was covered with gravel and cobbles, and flow was low but noticeable. We observed a pattern of riffles, where water flowed rapidly over rocks, and pools, where the water was stiller and deeper. We saw small fish in the pools, water striders on the surface and dragonflies flitting around the edges.
2. Peacock Creek, Irish Canyon, Black Diamond Mines Trail
Our next stop was Peacock Creek in Irish Canyon. We walked along the Black Diamond Mines Trail, an East Bay Regional Park District trail that leads to the park of the same name in the Kirker Creek Watershed.
With the Oakhurst Country Club clubhouse on our right and the golf course on our left, we proceeded up the trail, noting the fenced vegetated area that was required by the California Department of Fish and Game as mitigation for changes made to the creek when the golf course was constructed. Beyond the clubhouse and golf course was grazed land. We noted the stark contrast between the green irrigated golf course and the golden hills above it.
Initially, the creek appeared dry, but we observed water further upstream. The bottom of the creek was covered with fine sediment and cattails were growing in the channel. Laura Hoffmeister noted that flood control agencies often recommend removing vegetation to increase the capacity of the channel, while the Department of Fish and Game recommends leaving it in to enhance creek bed and bank stability and provide habitat. We saw a red-winged blackbird in the riparian area and a red-tailed hawk perched on a power line pole nearby.
3. Mount Diablo Creek, Clayton Library
Arlene Kikkawa-Nielsen was our host at the Clayton Library, where we learned about the library’s wildlife habitat gardens and the many nature programs they have presented to the community. An especially popular program was a butterfly incubation and release program. We sat in the learning circle by the creek while Mary Malko of Friends of Mount Diablo Creek described how her group and the library have worked together with volunteers to improve this interpretive area. We also discussed plans for future collaboration with the library on education and outreach about nature and watersheds.
Mount Diablo Creek is bordered in this area by the library and the golf course. Tall trees shade the area, while invasive plants such as Himalayan blackberry dominate the understory. Water was flowing in this reach and the bottom of the creek was covered with gravel and cobbles, coated by a layer of brown algae. The water was slightly cloudy and dragonflies were observed by a pool. A yellow swallowtail butterfly hovered nearby, apparently appreciating the habitat.
4. Mount Diablo Creek, Lydia Lane Park
Our final stop was Lydia Lane Park, where Mount Diablo Creek flows at the edge of the park parallel to Concord Blvd. We viewed Friends of Mount Diablo Creek’s water quality monitoring site at a gabion, i.e., a metal cage filled with rocks. Laura Hoffmeister said she believed the gabion may have been installed to prevent the creek from undermining the road.
We also observed the steep eroded bank at downstream end of park. An old wrought iron gate suspended over 25 feet above the bottom of the creek attested to an earlier time before the creek had incised, or cut down into its bed to its current level.
Water in this reach was clear and the bottom was covered with gravel and cobbles, coated with brown algae. Bright green algae were growing in a sunny spot in the creek. We noted the absence of a serious trash problem in the creek, which is quite unusual for an urban reach of a creek.
5. Mount Diablo Creek, Brazil Quarry Park
A few tour participants joined Friends of Mount Diablo Creek for their picnic in Brazil Quarry Park. This part of the tour was cancelled due the heat.
Mount Diablo Creek Upper Watershed Tour
Driving Directions
Bring water, snacks, a hat, and sunscreen. Wear comfortable walking shoes (closed-toe), long pants and long sleeves (layers).
Donner Creek, Donner Canyon, end of Regency Dr.
Take Clayton Rd. south until it becomes Marsh Creek Rd.
RIGHT on Regency Dr., drive to the end and park on the side of the road
Walk along the creek to observe conditions in Mount Diablo State Park.
Peacock Creek, Irish Canyon
LEFT on Marsh Creek Rd. It becomes Clayton Rd.
RIGHT into Black Diamond Mines Trail parking lot.
Walk along the creek to observe conditions next to grazed land and golf course.
Mount Diablo Creek, Clayton Library
RIGHT on Clayton Rd. RIGHT into Clayton Library parking lot.
View wildlife habitat garden and creek learning circle. Walk along trail that follows the creek.
Mount Diablo Creek, Lydia Lane Park
RIGHT on Clayton Rd. RIGHT on Lydia Lane, to end, park in lot.
View gabion and steep eroded bank at downstream end of park.
Mount Diablo Creek, Brazil Quarry Park
RIGHT on Clayton Rd., RIGHT on Ayers Road, LEFT on Sutherland Drive, and RIGHT on Kent Way.
View creek in the park and follow the trail along creek downstream of the park.