March 25, 2010

Pocket beach showcases low-impact elements

[enlarge]

The deteriorating bulkhead and shoreline along O Avenue was chosen as the mitigation site for shipyard improvements.

A new pocket beach located on Port of Anacortes property at O Avenue and First Street on the Guemes Channel combines shoreline restoration, public access and low-impact development features.

The beach is a mitigation requirement for the port's shipyard redevelopment project. As part of a public-private partnership with its tenant Dakota Creek Industries, the port redeveloped the shipyard and added two ship berths to increase DCI's operational capacity and flexibility.

Shoreline mitigation

To meet the permit requirements for in-water and shoreline redevelopment at the shipyard, the port was required to compensate for in-water area impacted by the redevelopment. The port determined that the O Avenue beach area would be an excellent mitigation site because it provided many opportunities for shoreline improvements. Historically, the area was the site of fisheries, canneries, mills and factories. Pier 1 is home to the shipyard and to the port's main offices, which are located in a multiuse building that also hosts community events.

The O Avenue site included an entirely paved upland area, held in place by a bulkhead that was failing in many locations. The mitigation work involved removing old creosote pilings and rubble from the shoreline, removing the old concrete bulkhead, regrading and replenishing the beach sediment and gravels, installing shoreline protection, and creating public access to the beach.

Shoreline protection included large rocks and boulders designed to allow planting between the rocks to improve shoreline habitat value.

Reconstruction of the pocket beach enhances the intertidal habitat in and along the Guemes Channel. Plants that stabilize the soil with their root systems and hang over the shore's edge can provide shading and also allow insects to drop into the water; key elements of habitat improvement.

Public access

Photos courtesy of HBB Landscape Architects [enlarge]

The newly planted rock revetment and sidewalk improve public access, shoreline protection and near-shore habitat.

An important element of the mitigation project included increasing public access to the beach and waterfront. A concrete sidewalk was added along the upland edge of the shoreline, with amphitheater stairs connecting the sidewalk to the beach. An old concrete platform was redesigned to serve as the base for a viewing terrace.

With new concrete surfacing, cable guardrail, an ornamental screen wall and seating, the terrace has become a public amenity with views of the channel and remaining industrial operations. The beach area allows refuge for small hand-operated boats.

Near the terrace is a small pocket park that was also renovated as part of the project. An existing coastal redwood tree is the centerpiece, with the addition of a new picnic table, bollards with solar-powered lights, and landscape screening. The plantings buffer the small park from an outdoor storage area and warehouse buildings.

Low-impact development

Partnering with the Skagit Marine Resource Committee, the port incorporated low-impact development elements into the project, including permeable pavers in the parking area along the street. Stormwater flows through the pavers and into the soil. A concrete accent band edges the pavers, providing extra stability. An interpretive sign explaining the LID projects and how they positively affect the environment is located along the sidewalk.

The large, blank wall of the Puget Sound Rope warehouse building offered an excellent opportunity to highlight the collection of stormwater from the roof. The artful use of colorful and larger-than-life watering cans celebrate the movement of stormwater as it flows from the roof to the rain gardens. Stormwater runoff from the adjacent roadway surface is also directed into the rain gardens.

When rain is not falling, the decorative pipe system continues to visually communicate the important connection between stormwater and living systems; a reminder of our connection to the water surrounding us.

Approximately 850 square feet of pavement was replaced with the planted rain garden swales. Plants adapted to the variable moisture and shade conditions serve to filter the stormwater before it enters the storm drains and outlets into the channel.

A Job Development Fund grant from the state Department of Commerce funded the pocket beach and a grant from the Skagit County Marine Resources Committee assisted in funding the LID elements.

Colie Hough-Beck, ALSA, is vice president and Dean W. Koonts, ALSA, is principal at HBB Landscape Architects in Seattle.

Other Stories:

• Sustainable Sites Initiative greens the landscape
  
• Snoqualmie Falls park ready for the next generation