Beltline Crossing Removal at “Secret Canyon”

Secret Canyon Creek Finally Sees the Light:
A Beautiful Urban Tributary Stream is Unearthed!

Removing an abandoned road and employing landform restoration techniques have restored Secret Canyon, a small tributary to Sulphur Creek in the Redding Arboretum by the River. Approximately 300 feet of stream channel was "daylighted" when the estimated 10,000 cubic yards of road fill (1500 dump truck loads) was excavated from the stream crossing and placed on adjacent cutslopes to restore the natural form and function of the tributary canyon.

In 1938 the "World's Longest Conveyor Belt" was built between Redding and Central Valley in order to transport gravel for the construction of Shasta Dam. The "Beltline Road" was about 11 miles long and constructed in a straight line by filling in many tributary streams along the way. Many of these streams have culverts in them that have been abandoned for decades.

One such culverted road crossing at Secret Canyon was identified in the Sulphur Creek Watershed Analysis (1998) as having a high likelihood of failing and discharging 4,000 cubic yards of sediment to Sulphur Creek through the Arboretum and thence the Sacramento River. This discharge could exacerbate the existing streambank erosion problems downstream, increase the potential for flooding and further degrade the riparian and salmonid habitat within Sulphur Creek and the Arboretum.

Sacramento Watersheds Action Group (SWAG) and the Sulphur Creek CRMP collaborated with Shasta College and the City of Redding (CoR) to request grant funding from the Department of Water Resources, Urban Stream Restoration Program. DWR subsequently provided $15,000 to be matched with in-kind donations of labor and equipment to be provided by SWAG, Shasta College and the City of Redding. Permitting for the project, CoR Grading Permit, CEQA, CDF&G 1603, RWQCB 401 took over two months to complete and work began on October 1, 2000.

Circa 1938 photo looking south from "World's Longest Conveyor Belt. Note Secret Canyon behind electric pole and cut slope south of that.

Bulldozers and hydraulic excavators were employed to excavate the road and place the fill on the adjacent cut slope from whence it came over 60 years ago. Shasta College classes, Watershed Restoration Practicum and Heavy Equipment Operations, used this project as a field laboratory, hands-on exercise in Landform Restoration, road-related erosion and ecosystem restoration techniques currently employed by the National Park Service in Redwood National Park and nearby Whiskeytown NRA.

The College provided a D-6 bulldozer, fuel/service truck, and a lowboy transport for mobilization. Another D-6H was rented and a generous sponsor provided a D-8 at a reasonable price. A very large hydraulic excavator (100K pounds) was partially donated and operated by an expert in road removal and watershed restoration.

The three bulldozers, operated by Shasta College Heavy Equipment students, worked 21 days. The excavator was used for about 4 days, and altogether about 3000 gallons of diesel fuel were consumed for the earth-moving work. The project took nearly twice as long to complete because amount of road fill in the canyon was underestimated by about 6,000 cubic yards. Early on the students encountered an abundance of large boulders that had been used within the fill material. These boulders made it difficult for the D-6’s to push fill out of the canyon and up the slopes. Fortunately, a local equipment operator loaned a D-8 which made the earth-moving work much more efficient. As the slopes steepened, the PC400 excavator was brought in for removing the last bit of road-fill.

There was much anticipation in the final hours as the top of the 64 year-old beltline culvert was finally exposed, and the work atmosphere was ceremonious as the excavator pulled out the corroded conduit. The Shasta College instructor, an experienced geomorphologist, directed the heavy equipment work. Working as a team, the channel bottom and streambanks were gently restored to the original gradient and form. This portion of the stream had not seen any light for 64 years.

The upper photo shows the beltline road “BEFORE” removal of fill material from the canyon. The lower photo shows the same view near completion of the project, before final seeding, mulching and revegetation.

Immediately after "daylighting" the stream, deer, raccoons, and other wildlife were seen utilizing the new (old) habitat. Several full-sized pine trees were removed as they were growing in the old road fill. Most of the limbs, brush and excavated trees were left lying on-site in a “lop and scatter” restoration technique that provides raindrop erosion control, wildlife cover and allows natural decomposition to take place. Exposed slopes were also mulched and seeded, at the end of each day after the critical October 15th deadline, for erosion control. A native seed blend was used consisting of Elymus glaucus (Blue Wildrye), Festuca idahoenisis (Idaho fescue), Bromus carinatus (California brome), and Deschampsia elongata (Slender hairgrass). Biodegradable straw rolls were also used to control sedimentation at the toe of the slopes and aide establishment of vegetation on the slopes.

The Watershed Restoration Students were also trained in Biotechnical Soil Stabilization techniques. These techniques are currently being adopted by Caltrans, Federal Highways and other agencies and municipalities charged with designing and implementing works that are structurally sound while providing habitat enhancements. The students employed techniques such as Live Staking, Pole Planting, Live Siltation and Brushlayering. These techniques used willow and cottonwood cuttings in combination with logs and boulders to structurally stabilize the new “daylighted” streambanks, providing both immediate and long-term erosion control as the live branch cuttings root and grow.

A community “Planting Day” was held shortly after completion of the project. Approximately 50 volunteers helped plant native vegetation on the restored slopes and along Secret Canyon Creek. Starbucks Coffee employees joined the volunteer team and also served hot coffee at the project site. Also volunteering were two Shasta College classes, Sequoia Middle School students, and other interested folks. A diverse variety of native container plants were planted at the site, including three different species of oak, some ponderosa pines, gray pines, coffeeberry, native blackberry, native rose, deergrass, sedges, and some grass plugs and acorns. Volunteers also learned biotechnical streambank erosion control techniques such as brushlayering, live siltation, and live staking.

After the stream was “daylighted”, volunteers planted a variety of native plants and constructed biotechnical erosion control structures which will grow and provide habitat. Shown above are Brushlayering with Log and Rock Toe (right) and Brushlayering with Straw Roll (left)

The students had opportunities to learn some bioengineering repair techniques during the winter. The hillslope, which was rebuilt up from the fill placement, experienced some fairly deep slumping. The fill placed against the old cut was pushed into place and compacted with the bulldozers. The completed slopes were about 20 feet high at about 2.5:1 (H:V). However, the entire cut was not fully restored and in some places subsurface drainage seeping out of the cut saturated fill placed below. About three slumps and gullies occurred which deposited about 15 cubic yards on the sewer access road below. The Shasta College class stabilized these areas with Live Smiles (woven willow fences shaped as catenary curves), Live Pole Drains (willow bundles serve as subsurface drains, and Slope Pinning (using willow stakes to "nail" and buttress slopes).

SWAG and the Sulphur Creek CRMP would like to thank the Department of Water Resources Urban Stream Restoration Program for the $15,000 in funding, the City of Redding as co-sponsors, the in-kind services from Shasta College, Turtle Bay, and the Department of Fish and Game, and special thanks to all those folks who volunteered time and resources for this ecologically-based project. This project could not have been successful without those who volunteered equipment, worked late each night, spread itchy mulch before the rains came, and tramped up and down the steep slopes with a plant under each arm.

The “Planting Day” event utilized community volunteers to revegetate the newly-reconstructed slopes and streambanks.

Shasta College Watershed Restoration students have continued to monitor the site and have repaired small slumps using biotechnical erosion control techniques, such as Live Smile above.