Our depth of experience in restoration techniques through our work with many contracting entities in a wide variety of conditions makes us a resource for our clients beyond the actual construction process. We are able to provide insight into construction methods that will improve the quality and cost effectiveness of the project while maintaining the integrity of the design and the restoration goals.
We offer the following services:
- Stream Restoration and Re-construction
- Wetland Restoration and Mitigation
- Civil Construction
- Parks and Trails
- Vegetation Management
- Revegetation/Erosion Control
Recent Representative Projects
Dry Creek Habitat Demonstration Project, Phase II
Sonoma County Water Agency | Completed Winter 2014 - 2015
The Dry Creek Habitat project consisted of habitat modifications within the Dry Creek Valley along Dry Creek. The habitat modification included new side channels, ponds, alcoves, and rock weir riffles; enhancements to existing pools through selective grading; installation of woody debris, log jams, and large boulders as anchor material; vegetation planting; installation of erosion control measures; excavation; and dewatering.
The project specifically included construction of 4,785 SF (~4,785 lift-feet of FES lifts) in two structures. Work also included diversion of up to 120 CFS flow on Dry Creek and daily monitoring by Tribal Representative. Hanford ARC was awarded 2 year, $4.5M contract through a pre-qualification process. All work was bound by resource agency permits including USACE, USFWS, NMFS, and other state agencies.
Napa River Rutherford Dust Reach 8 BC
Oakville and Rutherford, CA
Napa County Department of Public Works | Completed Winter 2013
This Phase 8 B/C of the Rutherford Reach of the Napa River project included the restoration of approximately 3,500 linear feet of the Napa River in Oakville and Rutherford, California. Overall the project included extensive grading, installation of bioengineering techniques and biotechnical structures, removal of non-native species, and revegetation with native plantings to convert former vineyard to riparian habitat. The work included grading and installation of bioengineering structures such as willow brush mat, vegetated soil lifts (VSLs), willow baffles and willow pole plantings. Existing steep river banks were laid back to create side channel alcoves to provide high flow refuge and rearing habitat for steelhead and Chinook salmon. Complex Large Woody structures and boulder clusters were installed at key areas along the new bench toes.
At the Bella Oaks confluence, streambank grading included the removal of 23,000 CY of soil. The work included the installation of in-stream log structures to create floodplain and terrace surfaces, as well as in-stream habitat and flow control. Construction of a step-pool rock structure allowed a transition to the existing Bella Oaks channel upstream of the confluence with the River.
The project specifically included construction of 1,489 lift-feet of FES lifts. Hanford ARC was awarded the contract through a pre-qualification process. All work was bound by resource agency permits including USACE, USFWS, NMFS, and other state agencies.
Cullinan Ranch Wetland Restoration
Ducks Unlimited (USFWS Lands) | Completed Spring 2013
The Cullinan Ranch is situated in the Napa River delta and was once a network of deep water channels and vegetated marsh plain. A century of active farming caused the land to sink as the rich organic soils of the marsh dried out and caused the site to subside below mean sea level. The project goals are to restore tidal influence to Cullinan Ranch allowing restoration of mature tidal marsh and provide a key public access point for the San Pablo Bay National Wildlife Refuge. Hanford ARC completed the components of Phase II, including the construction of the Highway 37 protection levee, improving the levee forming the western boundary of the site, installing public access infrastructure and constructing a 1.5 mile multi-use trail which connects to a viewing area on the South Slough, and building the 1,000 square foot pile-supported Fishing Pier, Aluminum Kayak Dock, and custom USFWS information Kiosk for the public..
The total earth moved was approximately 300,000 CY. Because of the soft substrate of bay mud and sensitive nature of the site, a combination of excavators, dozers, and scrapers were used to construct the levees to 90% of maximum density. Equipment was required to stay within strict boundaries so as not to disturb adjacent natural habitat and to remain out of Cal Trans right away, adjacent to the toe of the setback levee.
Salt River Ecosystem Restoration Project Lower Phase 2A
Humbolt County RCD | Completed Winter 2014
The Salt River Ecosystem Restoration Project (SRERP) was a multifaceted restoration project designed to restore ecological, geomorphic, and hydrologic function within the Salt River watershed. The Salt River watershed is an approximately
47-square mile watershed located within lower reaches of the Eel River basin.
Hanford ARC completed the components of Phase 2. Restoration activities within the Riverside Ranch and Salt River Channel required significant grading activities. Estimated excavation volumes were on the order of 60,000 to 80,000 cubic yards. Excavated materials were placed as berms within the project area or were thinly spread (less than 1-foot thick) on neighboring agricultural land. The work included grubbing, vegetation stripping, excavation, sediment hauling, water main replacement, placement of large wood habitat structures and seed/mulch application.
Twitchell Island Revegetation
Sacramento County, CA
Reclamation District No. 1601 | Spring 2000
Hanford ARC constructed this levee setback revegetation project, located in Sacramento County, Ca., in February and March of 2000. Prior to the project, 2,400 linear feet of new levee on the San Joaquin River had been constructed with a 100-foot setback from the old levee, which remains in place as a breakwater and revegetation planting zone. The project included the installation of nearly 24,000 herbaceous plants, 1,660 woody plants, and a temporary irrigation system. Hanford ARC is currently implementing an extensive three-year monitoring program, including weekly site visits and preparation of regular monitoring reports.
Our work was administered by Reclamation District No. 1601 (Twitchell Island) through Kjeldsen, Sinnock and Neudeck, Inc. of Stockton, Ca., also the designers. The levee setback and revegetation project is critical for the State Department of Water Resources (the funding agency), as it is the first of its kind in the delta, and the success may determine the extent of future funding by CALFED for similar projects. Hanford ARC and the project are under observation by numerous federal and state agencies.
A 3-year maintenance period was part of the contract. This was recently extended to four years, ending in April of 2004. This includes hand weeding, mechanical weeding, spraying, and operation of irrigation system. The irrigation system installed was designed by Hanford ARC and is wildland drip and spray head, operated by a 6” diesel pump. Plant protection was installed due to beaver damage. The protection included cones and weed mats initially. This was met with limited success. Continuing beaver damage required installation of wire cages on affected plants. This method has been very effective, allowing the plants to establish. Specifically affected by the beaver were the willows and cottonwoods. Also a part of the maintenance operations is continuing removal of invasive plant species including water hyacinth and cattails.
Devil’s Slide Mitigation
2005 - 2010
Wetland Mitigation is fortunately now an integral part of development. Construction of the Devil’s Slide Tunnel on Highway 1 between Pacifica and Montara, Ca. is causing impacts to sensitive coastal wetland and scrub habitat. Hanford ARC was contracted in 2005 to restore and mitigate for the impacts to red legged frog and sensitive coastal habitat for a majority of the Devils Slide construction impacts.
The contract involved excavation of a large wetland swale, pond, and associated upland in Montara, on the East side of Highway 1. Mobilization included grading and stabilizing a roadway with base rock and fabric. Straw barriers and silt fencing were installed to protect from wind and water erosion. Street sweeping and vacuuming were required to maintain strict water quality controls. Hanford ARC excavated approximately 20,000 cubic yards of soil, which was offhauled to a common disposal site for the Devils Slide project.
In addition to the earthwork, the project included revegetation with over 4,000 native container plants and seed. The soil was amended with 11,620 pounds of mulch and 1,650 lbs of mycorrhizal inoculum. Hanford crews hydroseeded the area with 745 lbs of pure live seed, and harvested and installed approximately 1500 willow cuttings.
Irrigation systems of PVC pipe, drip lines, sprinklers and emmiters were installed. Water sourcing proved challenging, and Hanford ARC must truck water from Pacifica to fill a series of five 2500 gallon water storage tanks to maintain the watering operations. A new electrical service powers a pressure pump and irrigation controller. The project includes a three year plant-establishment period, during which time Hanford ARC regularly maintains the irrigation system and provides invasive weed control.
Restoring Critical Dune Habitat to Protect Threatened & Endangered Species
Point Reyes National Seashore, CA
National Park Service, PORE | Winter-Summer 2011
Hanford ARC was awarded the Critical Dune Habitat Restoration project at Point Reyes National Seashore, through the RFP process in the winter of 2010/2011. The project is designed to restore approximately 76 acres of native dune habitat, primarily through removal of the invasive European beachgrass and iceplant. The project will benefit the federally endangered snowy plover and several species of federally protected dune plants. The work area is immediately west and south of Abbott’s lagoon, north of the Point Reyes lighthouse.
Hanford ARC is removing the beachgrass through both mechanical and hand methods. The mechanical method involves excavation to the rhizome depth of the beachgrass (3’-6’) to reach ‘clean sand’ which is then removed and used to create a 3’ cap over beachgrass, after it has been buried in the same or adjacent pit or trench. Essentially, the scope is to flip the sand horizon, burying the grass and rhizomes at a depth where their stored energy will not allow them to penetrate the surface and regrow. The hand removal consists of hand excavation of beachgrass and iceplant biomass, transport, and burial in mechanical excavation pits.
Although the project scope is invasive species removal, the work is very much mass excavation. When the project is complete, approximately 920,000 CY of sand will have been excavated. Six, 22-50 ton excavators full time, three D6-D8 size bulldozers full time, and intermittently one-two track trucks are required to maintain an average production rate of approximately 7,700 CY/day over 6 months.
Although the project is designed to benefit special status species, those same species present substantial challenges to construction logistics. The schedule and work areas are primarily dictated by nesting/breeding seasons and the proximity of sensitive habitat, including snowy plover nesting on the ocean-side of the dunes and red legged frog habitat on the inland side of the dunes. Work areas are strictly limited by a mosaic of native dune habitat patches amongst the invasive species dominated areas. We have installed both trenched and untrenched silt fence (20,000+ LF) to delineate the various work zone/habitat type boundaries, and are limited to hand removal in areas where sensitive species occur within patches of invasive species, primarily at the limit of the invasive species infested areas.
Trout Creek Stream Restoration and Wildlife Enhancement Project
South Lake Tahoe, CA
City of South Lake Tahoe | Summer/Fall 2000
Hanford ARC (prime contractor) and Frontier Contracting (sub contractor, operating specialized equipment) constructed this second phase of a comprehensive floodplain and habitat restoration project. Designed by Watershed Restoration Associates of South Lake Tahoe, restoration involved construction of approximately 5,700 linear feet of stream channel with features including sod bank revetments, rootwads and placed gravel bars and riffles.
In the project area, Trout Creek flows through a meadow at a low gradient (<2% slope). Historically, the stream was relocated to allow for a railroad bed. During this relocation, the stream was straightened, effectively shortening the channel length in the valley (reducing sinuosity), and increasing the gradient. The channel incised, limiting flooding on the floodplain terrace. The groundwater table dropped simultaneously, changing the vegetation composition in the wet meadow.
With the railroad gone, the opportunity existed to return Trout Creek and the surrounding meadow to historic conditions, and improve the habitat value of the local environment.
A new, meandering channel, with an 18-foot wide (average) cross-section and greatly increased sinuosity, was constructed. The channel substrate, including gravel bars, riffles and pools was constructed at an elevation 2 to 3 feet higher than the existing creek. Rootwads were placed at the outside bends of the meanders and four grade control structures with sills were installed at the downstream end of the project to transition the new channel to the old.
The revegetation component included harvesting of meadow sod for a stacked sod revetment on outside bends (coined 'deformable bank structures'), and replacement of sod on the channel banks. The sod revetment was staked with live willow cuttings. Also, willows that were removed for channel excavation were transplanted as encountered.
Giacomini Wetland Restoration
Point Reyes National Seashore, CA
Point Reyes National Seashore Association, Point Reyes National Seashore | 2008
In 2008 Hanford ARC was awarded the second phase of the Giacomini Wetland Restoration Project. 10 years in planning, the completed Giacomini project restored 12% of California’s outer coastal wetlands and 50% of Tomales Bay wetlands. The Giacomini Dairy leveed a tidal zone of lower Lagunitas Creek in the 1940’s to reclaim the land for cattle grazing. The Dairy drained the land through a series of ditches and filled portions of Tomasini Creek, a tributary to Lagunitas Creek. In 2000 the National Park Service acquired the Waldo Giacomini Ranch.
The first phase of the project was completed in 2007, and included demolition of the dairy infrastructure and red-legged frog mitigation wetlands. The second phase, constructed by Hanford ARC consisted of removal of approximately 3 miles of levees, construction of new tidal channels including the 50’ wide lower Tomasini Creek, backfilling drainage ditches, removal of dairy infrastructure, and construction of marshplain and floodplain benches. Although at the start of the project the work area was leveed, most of the 550 acre project area, spanning both sides of Lagunitas Creek (east and west pastures), was delineated jurisdictional wetland.
Construction presented major logistical challenges. The total earth moved was approximately 125,000 CY. Because of the soft substrate, and sensitive nature of the site, scrapers were not an option. In addition, for at least ¼ of the project area, wheeled equipment was not an option. This limited our choices of equipment to primarily tracked. We did use off-road haul trucks on designated routes to move levee soil to the dairy ‘mesa’, both a disposal and transfer site. We hauled approximately 22,000 CY to two quarries within the park which we closed with the soil.
Certain areas of the project were so soft that we used low ground pressure (LGP) tracked equipment to perform all work. This included excavating and transporting approximately 3,000 CY of sediment from lower Tomasini Creek using an LGP excavator and LGP tracked trucks. Other specialty equipment included a long-reach excavator and LGP bulldozer. Where LGP equipment did not have the capacity to meet the required production, we built and maintained temporary roads over existing ranch roads to handle regular off-road truck trips. As we completed zones of the project, we removed the temporary roads, as well as the ranch road underneath, and ripped the soil for decompaction.
Scheduling was very complicated. The primary schedule drivers were permit conditions and tides. Aside from jurisdictional wetland status, the ditches contained tidewater goby, a federally endangered species, the uplands were potential black rail nesting habitat, a state threatened species, and Lagunitas Creek contains coho salmon and steelhead, both federally endangered. These species all require specific timeframes to minimize disruption to natural processes such as nesting, migrating and spawning. Our work areas were divided by zones to accommodate the biological restrictions.
We worked closely with the National Park service to clear areas prior to construction activities within the areas. This included carefully paced clearing in potential nesting areas, proceeded by a biological sweep, and careful dewatering of drainage ditches. We assisted the park with setup of fyke nets to screen for tidewater goby, and adjusted dewatering operations as necessary to facility proper flows for screening.
Tidal influence was a substantial factor throughout the project, but especially near the end. Because most of the project area would be diurnally flooded after the levees were removed, we could not completely remove the levees until the work on both pastures, including channel and marshplain grading was complete.
In order to manage the remaining levee soil without transport, we constructed temporary berms along Lagunitas Creek, with an inboard trench or low area with the capacity to receive the soil. This proved effective. We were able to perform the final breach of the levees in one day for each pasture.
The restoration design incorporated habitat enhancement details such as high tide rail (waterfowl) refugia and water retention segments within tidal channels (goby habitat), and floodplain basins on upper Tomasini Creek (red-legged frog habitat). The design also included specific hydrologic features such as a ‘high flow bypass’ and 16 acre marshplain enhancement area to encourage Lagunitas Creek to reconnect to its historic floodplain.
Beyond the primary project area, the NPS incorporated two additional project areas. One, mentioned already, is located on two ranches between Sir Frances Drake Blvd and Pierce Point Road to the west of Inverness. The park utilized fill generated from the Giacomini project to close and restore two quarries on these ranches.
As part of our contract, we transported, placed and compacted the soil in the quarries, and provided erosion control. The second work area was located at Olema Marsh, just south of the Giacomini project. The work at this site included reconnection of an existing freshwater marsh to Olema Creek. The work required LGP equipment. The intent at this site is to restore a more natural hydrology to Olema Marsh.
The Giacomini Wetland Restoration project has since received notable attention, including newspaper articles in the Los Angeles Times, Marin Independent Journal and Press Democrat.In May of 2009, the project received the Partners in Conservation Award presented by Secretary of the Interior Ken Salazar. Hanford ARC is named among the project partners, and thankful to be considered for its contribution. The award and recognition we have received surrounding this project demonstrates our cooperative approach to construction. We bring this approach to each project.
Redwood Creek Restoration at Muir Beach
Golden Gate National Recreation Area, CA
Golden Gate National Parks Conservancy, in partnership with the National Park Service | 2009 - 2011
In July 2009 Hanford ARC began a three year project with the Golden Gate National Parks Conservancy (GGNPC) to restore Lower Redwood Creek and Big Lagoon in the Golden Gate National Recreation Area (GGNRA). Redwood Creek, which flows to the ocean at Muir Beach, was restricted through historical development for ranching and recreation. Impacts included levees, lagoon filling, and channel relocation. Work included lagoon expansion, fill removal, channel realignment and bridge replacement. The primary goal of the project is to increase rearing habitat for the federally listed coho salmon and steelhead populations that have historically used the watershed. In addition, the project will increase habitat for the California red-legged frog, also a federally listed species.
Our scope for 2009 was defined by the need to provide immediate improvements for the dwindling population of Coho Salmon that rely on Redwood Creek for spawning and rearing habitat. We substantially increased the size of the existing tidal lagoon by excavating an off-stream tidal basin, and constructed seven log structures at the perimeter of the lagoon. The basin is fully connected to the existing lagoon, and will capture flood flows from Redwood Creek.
We restored the floodplain on the right bank of Redwood Creek upstream of the tidal lagoon. This work involved removing the end of the beach parking lot, including relocating restrooms and fencing. This was considered an interim solution, with the long-term solution being full realignment of the parking lot in a future phase.
The 2009 work included a mitigation component as well. California red legged frog have historically inhabited the project area. To offset temporary impacts to the riparian habitat and to encourage potential reestablishment of red legged frog in the area, we constructed a frog pond on the east side of the historic lagoon and future channel alignment. This work included excavation and berm construction.
Other notable components of 2009 included native sod salvage and replanting, screening approximately 1,000 CY of sand for weed removal, working with archeological and historically significant features, and routing public access to minimize impacts to recreational users on this very popular beach.
The 2010 phase consisted of construction of 650 feet of the new Redwood Creek alignment and three tributary channels, installation of log structures, harvest and replacement of 1,500 CY of native streambed gravel, and construction of a red-legged frog pond.
The native gravel harvest was a substantial portion of the 2010 work. It required dewatering of approximately 2,000 LF of the existing stream channel and removal of an average of 2’ of streambed gravel. We reconstructed a new channel bed and low flow channel within the existing channel to minimize impacts to spawning fish during the winter of 2010/2011.
We completed approximately half of the project scope, the final of the three phases, in 2011. This phase included constructing an upstream and downstream segment of realigned channel, tying the new channel to the old channel, backfilling the old channel, a backwater channel and frog pond, removal of a levee and construction of a 215’ pedestrian bridge set on torque-down piles and pile caps.
The schedule was accelerated based on permit constraints from multiple agencies, including NMFS, RWQCB and USFWS, and required simultaneous channel construction and bridge construction activities to be carefully coordinated. Part of the project included removal of a levee which also served as the primary access route, and intersected the new channel alignment. We established an extensive, 24-hour bypass system to capture water in the main stem and tributaries, and a 24-hour site dewatering system to maintain dry work areas below the water table. Much of the work in the new channel was below the higher-high tide elevation.
Backfill and interception of the existing channel included sheetpile, a rock revetment, and a vegetated soil lift structure. The new channel included a series of log structures that provided cover and bank stabilization both upstream and downstream of the 2010 channel segment. We worked closely with the design team to locate and set the log structures.
In addition we harvested approximately 600 tons, and imported approximately 1,400 tons of streambed gravel to augment the channel bed with a 1-2 foot layer of gravel. The harvested gravel was removed from the existing channel prior to backfill.
The 215-foot pedestrian bridge included three pile clusters and pile caps, and one abutment. We installed torque-down piles, driven up to 55’. The bridge itself is an aluminum welded structure, with wood decking. We set the bridge in two 90’ sections and one 45’ section with a 200’ crane. We also constructed a landing and new trail section on the south approach, including gravel paving and visitor amenities.
For all three phases of work we used our GPS system for layout and as-built records. This involved establishing a permanent base station and calibration using a series of surveyed points at the perimeter of the project. NPS will use data from our records as a baseline for monitoring sediment transport and channel migration.