Los Angeles River in the San Fernando Valley, 2000
Photograph by author
CONCLUSIONS
As noted by other commentators and analyzed by this exhibit, the Los Angeles region is one of the most flood-prone, park-poor, and water-hungry urban areas in the country. The combined problems these issues represent force the Los Angeles River into the regional planning conversation. Under a strategy of NEGLIGENCE that ignores the river's urban design potential the problems of flood control, park shortages and water supply will simply expand and become more extreme as the region's population grows in the next 25 years.
But the clock of time and urban development can not be turned back. A complete RESTORATION of the river's pre-urban, 300 square mile floodplain is, of course, an impossibility.
Yet more modest efforts to restore portions of the historical river landscape suffer from a variety of political, economic, social, and environmental problems. Developing political consensus about the Los Angeles River's future requires navigating the patchwork of political entities claiming jurisdiction over the river corridor, ranging in scale from multiple municipal governments to various Federal land management agencies. Based on the Friends of the LA River and Army Corps of Engineers' estimate of $125 million for acquiring the quarter square mile of the Taylor Yards north of downtown and restoring the riparian landscape of the river, $1 billion must be spent to create 2 square miles into river park corridors. This number, however, does not include demolishing the existing flood control infrastructure of the river, which represents millions of dollars in physical investment. Consequently, converting 80 square miles of the 100-year flood plain into extensive river parkways, as proposed by the SURRENDER scenarios, carries the same price tag as the 1994 Northridge earthquake. Yet despite the immense economic costs associated with greenways along the river, its primary beneficiaries as a park would be people living within one mile of the river. At regional level, the measurement of cost against social benefit fails to justify the creation of extensive riverine parks. Finally, expanding the river corridor to accommodate more water only addresses the symptom of the flood threat and not its cause. Real solutions to the flood problem must prevent water from entering the storm drainage system through on-site water retention basins.
Although within a 50 to 100-year time frame, as former industrial sites along the river corridors become available, every effort should be made to acquire these properties for river restoration, the GREEN STREETS proposal offers a more immediate, economic and practical solution to the watershed problems analyzed by this exhibit. As many of the region's roadways are administered and maintained by the Department of Public Works of the County and various cities, the political negotiations and logistical problems of implementing Green Streets are significantly less than developing park corridors along the river. If viewed across a 25-year future, the lifespan of an average roadway, the financial logistics of Green Streets are also more favorable, as they can drawn upon routine operating costs for financing. Although the expense of constructing Green Streets at $1.5 million a mile is 150 percent greater than the average streetscape improvement, the cost per park acre is less than river restoration ($0.25 million for Green Streets versus $500 million for river restoration). Since the one-mile grid of boulevards covers the entire basin, Green Streets create new parkspace within a half mile of the entire population, instead of just those living adjacent to river channels. Thus the social benefit versus cost increases the economy of a Green Street park strategy, benefiting 7000 people within one mile for every $1 million spent on parks, versus river greenways' 140 people. Finally, the 18 square miles of porous ground surface created by 2000 miles of Green Streets addresses the flooding problem at its source, reducing stormwater to the flood control system by distributing a grid of aquifer recharge zones across the entire basin.
Nonetheless, the optimum solution to the problems analyzed in this exhibit will and should be hybrid between these and other propositions; no proposal can simultaneously increases parkspace and local water supplies while reducing flood threats with one single, grand solution. But by isolating various river design strategies, this exhibit has sought to examine each proposal's implications, shortcomings and merits as measured against one another and the historical context of the river. As such, its intention has not been to resolve technical design problems, but to investigate the river's significance, its meaning, and its potential. Through sharing this research, the purpose of this exhibit is to educate, to foster informed citizens. For the issues that surround the Los Angeles River affect everyone living within its watershed; the river's future is also their future.