Stormwater & Flood Control Planning & Design
Client: Sempervirons Fund and Peninsula Open Space Trust
Mill Creek is the largest tributary of San Vicente Creek, in Santa Cruz County, an important stream for steelhead and coho salmon on the central California coast. Mill Creek drains a small, steep watershed containing a localized area of granitic rocks within the highly erosive marine sediments that dominate the Coast Range. Because of this, Mill Creek is an important source of resistant spawning gravel, which is limiting for fish in many watersheds in the central Coast Range. Within the recently-acquired San Vicente Redwoods Preserve, two dams on lower Mill Creek impound gravel and prevent fish passage.
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: Coastal San Luis Resource Conservation District
Channel and riparian conditions along Tally Ho Creek within the project area have changed significantly over the last several hundred years. Pressure to utilize flat valley bottoms for agriculture and, later, suburban development, resulted in removal of much of the riparian vegetation, filling of wetlands, road building, and straightening and deepening of Tally Ho Creek. Cleared portions of the valley bottom now consist of single-family homes and Tally Ho Road. Tally Ho Creek has been confined to the eastern edge of the valley floor.
Waterways is supporting Central Coast Wetlands Group by leading the design team in development of plans to construct a 30 acre managed wetland to treat irrigation runoff within the Elkhorn Slough Watershed.
Client: Town of Truckee
Over the past 150 years, Trout Creek, a tributary to the Truckee River, has been impacted by development of the downtown, the railroad, and other land uses. These impacts have resulted in channelization and realignmentof Trout Creek, upsetting natural channel processes such as bed load movement, habitat creation, hydrology, and wildlife corridors through loss of riparian habitat. Despite past efforts to “control” Trout Creek, flooding has remained a significant problem. In addition, the biological and aesthetic value of the channel was degraded.
Clean Water Service (CWS) is tasked with managing stormwater in portions of Washington County, OR that fall within the Urban Growth Boundary with the goal of protecting waterways and natural resources within stream and wetland corridors. When a new development is proposed, CWS works with the developer to meet regulatory requirements associated with increased runoff from impervious surfaces with the goal of maintaining discharges of stormwater to pre-development conditions. Traditionally, meeting these requirements consists of designing and constructing large, regional stormwater management facilities in upland areas adjacent to the new developments.
Client: South Coast Habitat Restoration
Waterways was retained by South Coast Habitat Restoration to prepare designs for improving fish passage at five barriers along Gaviota Creek. The sites are located north of Gaviota and directly adjacent to Highway 101. Each barrier is composed of a concrete grade control structure, originally installed to keep the creek from undermining Highway 101. Design concepts range from structural modification of individual weirs to complete removal and channel realignment.
Client: West Valley College
Waterways has provided comprehensive planning, grant writing, surveying, design, construction support, and post construction monitoring services for five distinct projects within the West Valley College campus.
- A stream restoration project to restore over 600 linear feet of Vasona Creek within the campus;
- A wetland creation project;
- A 20 acre Riparian Planting Plan along Vasona Creek within the campus, and
- A riparian trail system to provide enhanced access and learning opportunities.