The River Strand

The Piggyback Yard Conceptual Master Plan envisions a vast, new park offering a wide range of activities for a diverse community, a developed mixed-use Mission Road corridor, an Arts Campus, a restored Los Angeles River and a new Transit District adjacent to Downtown and central to the Los Angeles Metropolitan area.

The River Strand variation proposes to divert water from the Los Angeles River into emergent wetlands constructed on the Piggyback Yard site. The existing channel would be redesigned as a series of terraced pedestrian and bike pathways allowing the people of Los Angeles to experience the river first-hand throughout the year. The river itself would be reverted back to a planted, soft-bottom riverbed, enabling a riparian ecology to once again emerge. The River Strand seeks a solution that is an optimum balance between water management and ecology.

A key component of the River Strand variation, the Strand landform allows for the redirection of water during high seasonal flows in order to decrease river velocity and reduce flooding downstream.

The Yard’s topography is contoured to allow water to inundate the site during unusual storm events by excavating a ‘container’ for maximizing flood capacity. The stepped terrace landform permits flooding while providing for atoned habitats on several levels.  Occupied permanent building program is organized along its two urban edges, set on higher ground.  Open space program is also designed by elevation, with passive program more amenable to occasional flooding lying low, near the wetlands, and active program requiring more support facilities sitting on higher plateaus.

The Strand shapes the western edge of the detention basin and functions as an ecotone, or transition space of special habitat with two distinctly different edge conditions – a fortified, riparian river edge and palustrine wetland edge.  A new infrastructure of “River Overlooks” along the Strand supports rail trestles while offering opportunities for people to safely engage with the dynamic qualities of river, rail and habitat.

Inside the Yard on the Strand’s eastern edge, the year-round diverted river water feeds a constructed wetland at the lowest elevation of the Yard, filtering and treating seasonal water flows and serving as a major bioremediation component.  This wetland is also fed by daylighted creeks that convey and filter off-site stormwater through bio-swales on-site prior to entering river.

Longitudinal Section: Topography + Program. Cutting through the entire site from the Transit District on the west (left) to the 5 freeway on the east (right), this section demonstrates the strategic shaping of landforms to accommodate multiple built (transit, mixed-use, hospitality, cultural, etc) as well as open space (hiking, biking, picnicking, soccer, baseball, etc) programs. The Strand height is set at approximately 45-feet above river channel depth in order to maximize the Yard’s detention capabilities.

Section A: River Zone. Cutting through the River channel, the Strand and the newly created wetland, this section details the nuanced edge conditions of the River Zone. In keeping with the high-density Transit District development proposed to welcome the new intermodal High Speed Rail Station (left), this urban edge retains its structured character but introduces terraces of accessible promenades and ped/bike paths atop and within the former channel. Meanwhile, the Strand and Great Lawn offer softer edge conditions conducive to habitat restoration. Buried water storage increases capacity for water storage, filtration and reuse for proposed development.

Section B: Mission Road Corridor – Incubator. Cutting through the southern edge of the site from the Strand (left) to the Educational/Cultural Crossroads (right), this section details the cascading outlet of the wetland well as the southern entry to the Mission Road corridor. The extension of the Metro Gold Line along Mission Road supports this burgeoning economic strip by offering incubator development opportunities in the Yard and a place for a world-class research and training facility such as the Climate Change Center. Supported by ground-floor retail and community amenities, the pedestrian friendly green-street takes advantage of the topographical opportunity to create underground parking without the need to excavate.

Section C: Mission Road Corridor – Established. Cutting through the southern edge of the site again, this time further along Mission Road, this section details the interaction of the park’s active play area and botanical gardens (left) with a vibrant mixed-use community and across Mission Road to the Cleantech Corridor (right). Development in the Yard as shown here has grown up and out, providing a place for larger, more established companies to invest in the properties on either side of Mission. A series of festival plazas and semi-public green roofs mitigate between park and development, while low-height street faces backed by more tower-like conditions maintain a pedestrian friendly scale on the boulevard.

Section D: Alhambra Greenway. Cutting through the northern edge of the Yard, this section details the creation of the “Alhambra Greenway” pedestrian and bicycle path. The Greenway runs alongside but slightly lower than the existing rail lines, extending from the River well into Lincoln Heights. The earthen berm inside the Yard is built from excavated soil from the park itself and serves many purposes: edge for detention basin, seating for amphitheater, coverage for rail yard, platform gallery for Artist District and bridge to the park to the Brewery Arts Complex.

The above diagram illustrates how the Broadened River concept fulfills the promise of the four design principles established by the Piggyback Yard Collaborative Design Group, which are categorized and layered by water, open space, connectivity and community.

View 1: The Yard. Piggyback Yard Park provides approximately 130-acres of additional open space to the Los Angeles community, and ensures year-round activity through multivalent programming that includes play, live, work, relax and even flood detention. Preserving key views of downtown (this one taken from the northeast entry to the site below the 5 freeway) amidst a verdant setting figuratively reconnects Angelenos both to nature and to their City while literally connecting them through pedestrian bridges across the River in the distance.

View 2: The River. Having returned the River to soft bottom at the Yard, the view from the Cesar Chavez Bridge north becomes a mesmerizing scene of sediment islands within the River extents. A rider on the proposed Metro Gold Line extension would see something similar en route to the Mission Road Corridor. To the west (left), the Transit District’s promenade and terraced ped/bike paths enliven the River’s urban edge. To the east (right) the Strand peeks from below the rail trestle, populated with day hikers visiting from the Park beyond.

View 3: The Arts. The earthen berms on the northern edge of the Yard not only provide for multiple levels of programming below (rail yard, water storage, amphitheater) but also create stellar views of downtown 24/7. Here on this Artist Live/Work plateau, salvaged shipping containers congregate to form a series of galleries for use by the artists-in-residence. Connected to the existing Brewery Arts Complex across the Alhambra Greenway via a pedestrian bridge, these two entities combine to form an expanded Artist District.

View 4: The Promenade. As counterpoint to the naturalized River and wetland edges to the east, the urban promenade periphery of the Transit District encourages dense, vibrant program that compliments the arrival of a major intermodal transportation hub such as the high speed rail station. Riverside hotels, restaurants, bars, shops and other lively establishments line the rim, offering incredible views of the River and Piggyback Yard Park to the east (right). Access to the River’s pedestrian and bike paths below is granted through a series of river terraces spaced regularly up and down the promenade.

The Site Model, showing the Conceptual Master Plan in its larger context, illustrates how the Piggyback Yard can help nourish and connect so many different communities of Los Angeles and help reconcile the City and its River.