Client: Latimer Environmental
The Hillsboro Landfill is a construction-demolition waste landfill situated on 400 acres south of Hillsboro, Oregon between SE Minter Bridge Road and the Tualatin River. With the landfill operations located at the northeast end of the property, the south and west sides of the property contain wetland mitigation sites adjacent to the Tualatin River. Waterways was retained to design an outfall from the constructed wetlands located at the south end of the property that provides a geomorphically stable discharge into the Tualatin River.
Client: Santa Cruz County Community Action Board
Waterways staff was retained to develop a fish passage improvement design for a concrete culvert that was hindering fish passage on Valencia Creek, in Santa Cruz County. Plans were developed to construct a concrete fish ladder structure, per design criteria established by the National Marine Fisheries Service (NMFS) and the California Department of Fish and Game (CDFG).
Client: City of Watsonville
Under Phase 1, Waterways staff designed a seven mile network of pedestrian and bicycle trails along the Watsonville Sloughs System, within the City of Watsonville. Our scope included the preparation of a Trails Master Plan, identification of opportunities and constraints, engineering feasibility assessment, hydraulic modeling, final plans and specifications, permit support, and construction monitoring. The trail designs were implemented successfully, creating public access footpaths and bicycle trails with trail segments that also provide Americans with Disabilities Act-compliant access. Design challenges included multiple slough crossings (boardwalks), retaining walls, and bridges constructed on peat soils within a complex hydrologic regime. Design of each trail segment offered opportunities for ecological restoration, including removal of exotic vegetation and re-vegetation with native communities.
For phase 2, Waterways created a Master Plan for over 25 additional miles of trails within and adjacent to the City of Watsonville. Waterways is currently preparing 100% designs for portions of the Phase 2 trails system.
Client: City of St. Helena
Waterways staff worked with the City of St. Helena and a team of consultants to design, permit, and construct a multi-objective flood control project that provides 100-year flood protection for residential properties along the Napa River, restores important floodplain and aquatic habitat, and improves public access. Specific elements of the project include a geomorphically-based floodplain terrace, shoreline restoration involving removal of an existing gabion and rip-rap bank protection structures and replacement with a natural point bar shoreline configuration, bioengineered bank stabilization structures, FEMA certified levee setbacks and floodwall construction, relocation of homes from the floodplain, and approximately 2,500 ft of pedestrian trails with interpretive signage.
Client: MCS, Corp.
Waterways recently prepared detailed engineering plans and specifications to construct a wetland mitigation site in the historic floodplain of Yakima River in Washington. The site was historically leveled and channelized for livestock grazing before being purchased by the Bureau of Land Management (BLM). BLM has been managing the property to reduce invasive weeds for several years in anticipation of this project, which was initiated as a mitigation site for a nearby gravel mining operation with direct impacts to a nearby wetland.
Client: US Forest Service
Waterways staff led an interdisciplinary team to assess existing conditions within the Blackwood Creek Watershed, and then prepare detailed engineering plans and specifications for recommended projects. Blackwood Creek is a major tributary to Lake Tahoe, drains a mix of steep volcanic and granitic terrain, has a high bedload transport rate, and was historically impacted by grazing, logging, and instream gravel mining. Key impacts identified during the study were excessive bank erosion and channel widening associated with channel incision and loss of floodplain connectivity and the presence of several fish passage barriers. To restore the physical processes that sustain channel morphology and biological function, an aggressive, long-term restoration strategy was proposed. To date, four distinct restoration projects have been designed and implemented:
Client: City of San Jose
Waterways staff was retained to assess existing conditions and provide recommendations for enhancement of riparian and aquatic habitat along 2.5 miles of stream channel within Alum Rock Park, in the City of San Jose. The assessment identified Quail Hollow as a high priority project site based on fish passage impediments, stream channel erosion, and recreational access concerns.
Client: Town of Truckee
The Town of Truckee has partnered with the Truckee River Watershed Council and Truckee Development Corporation in a multi-objective redevelopment project that seeks to revitalize the downtown and the adjacent rail yard, reduce flood risks for businesses and residents, and improve the natural environment. The focus of this project is restoration of Trout Creek and development of open space that connects residents and visitors of the Truckee area to important natural resources. Waterways is leading a team of consultants tasked with enhancing habitat values and functions of Trout Creek.
Client: Resource Conservation District of Santa Cruz County
Waterways contracted with the Santa Cruz County Resource Conservation District (SCRCD) and the State Coastal Conservancy to provide design services for the improvement of fish passage at a stream crossing along Shingle Mill Gulch. The project site had a 6-foot diameter corrugated metal pipe culvert which provided conveyance beneath a private driveway servicing the Koinonia Conference grounds. Hydraulic analyses of the culvert determined that it was undersized for design flood flows and presented a fish passage impediment to migrating salmonids.
Client: The Nature Conservancy
Independence Lake holds one of only two known wild, self-sustaining populations of Lahontan cutthroat trout in the world - a species that has been lost from 99% of its historic range. Waterways staff are proud to have assisted The Nature Conservancy in their efforts to protect and restore this critical habitat through the planning and design of a barrier to exclude non-native fish from the lake.
Client: Boy Scouts of America, Monterey Bay Area Council
The Boy Scouts of America own and operate an 800-acre property on the Little Sur River that is used as a summer camp. A flashboard dam was installed in the 1950s to create an impoundment for recreational and educational uses. The seasonal operation of this dam impeded juvenile and adult steelhead passage at the site
Client: Wasco County Soil and Water Conservation District
Mill Creek is a moderately-sized tributary to the Columbia River that originates on the eastern slope of Mt. Hood and flows northeast through the City of The Dalles, Oregon. Urbanization along the lower two miles of Mills Creek in the City of The Dalles resulted in the simplification of the aquatic and riparian habitats. In 2011, The Dalles Watershed Council (DWC) commissioned an evaluation of the urbanized reach to assess land use impacts and identify opportunities for habitat restoration. Following the initial assessment, a preliminary engineering design was developed for the Honald/Buyers property. The preliminary design included excavation and connection of a historic side channel that had been partially filled, utilization of an existing side channel as a backwater alcove, installation of a precast spanning bridge across the reconnected side channel, and installation of large wood structures along the channels and floodplain to increase roughness and improve habitat conditions.