The Army Corps of Engineers recently released the long-delayed Los Angeles Ecosystem Restoration Integrated Feasibility Report, a 500-plus-page document examining possibilities for restoring the Los Angeles River. The report changes the focus of the Army Corps—the same power that originally encased the river in concrete as insulation from its seasonal fluctuations—by recommending habitat restoration along an 11-mile stretch of the river, roughly between Griffith Park and the 101 Freeway in Downtown.

“The Corps sees the value of urban ecosystem restoration,” said Josephine Axt, chief planner for the Los Angeles District of the Army Corps. “There are ecological benefits ascribed to this project.”

The report, started in 2006, examines four alternatives, evaluating each for benefits in open space, restored ecological systems, economic development opportunities, and improved management of local water supply. Among these are Alternative 13, a $442 million suite of projects that would represent a smaller investment than Alternative 16 ($757 million) and Alternative 20 ($1.04 billion). Advocates for the river, still in the process of formulating a coordinated response to the report, overwhelmingly prefer Alternative 20.

Among the proposals of Alternative 13 is the ecological restoration of Taylor Yards, located between the 2 and 110 freeways. There the Army Corps would widen the river’s natural bottom by about 300 feet and allow it to reconnect with its flood plain, creating a wetland. The project would also built a gradual riparian slope along 1,000 feet of the river and create a small terraced area at the project’s downstream end. Also included is the removal of concrete from the riverbed along a half-mile on the Arroyo Seco before its confluence with the LA River, along with riverbanks restructured to support the vegetation.

Alternative 20 would restore this stretch and also tack on a “full restoration” of the 125-acre Piggyback Yard, a rail yard currently owned by the Union Pacific Railroad. There the Army Corps would remove concrete from .75 miles of the river and terrace the riverbank. Alternative 20 would also restore the river’s confluence with the Verdugo Wash further upstream, an area currently blanketed by freeways and industrial facilities.

The Army Corps is recommending Alternative 13 because, it says, it delivers the highest value in habitat restoration. But Axt acknowledges why advocates prefer Alternative 20, which would pull more concrete from the river: “People are really excited about the idea of reshaping the concrete—opening habitat and public access.” In late September, supporters held a rally for Alternative 20, while LA Mayor Eric Garcetti’s office is circulating a petition in favor of the option.

Regardless of which alternative is chosen River advocates are calling the Army Corps’ report a historic opportunity. “This is what we’ve been dreaming of for 25 years,” said Alejandro Ortiz, chairman of the board of the non-profit Friends Of the Los Angeles River (FoLAR) and principal of Alejandro Ortiz Architects.

Ortiz believes that the habitat restoration proposed by the report will make the city a more beautiful and desirable place to live and work. Still he’s clear that Alternative 20 includes the projects with the most powerful potential benefit to the city: “There’s no question that the most critical site on the entire river is Piggyback Yard.”

The future of the river must still be debated in Washington. The current draft report should be finalized early in 2014, after a 45-day public comment period. Then the executive leadership for the Army Corps and the Office of Management and Budget will review the report before Congress can authorize construction in the Water Resources Development Act (WRDA), currently in committee. Funding for construction will also require a separate act of Congress. The most recent WRDA bills passed in 2000 and 2007.

“We don’t want to miss the window of opportunity,” said Axt. Congress has, in the past, supported local goals to revitalize the river, mandating in the 2007 WRDA that the Army Corps develop its current report consistently with the goals of the city’s 2007 Los Angeles River Revitalization Master Plan.