Originally published by Plaza de Armas

When the city of San Jose, California, was redeveloping its downtown in the early 1980s, initial master plans completely ignored the Guadalupe River, which runs along the edge of the central business district. Helen Meyer Harrison and Newton Harrison, a pair of social and ecological artists working at the State University of San Jose at the time, responded with The Guadalupe Meander, A Refugio for San Jose, which began by asking the mayor and city council: “Can it be that you have forgotten your river?” 

In a later interview, the artists recall that “[from] a proposal for a refuge, the work turned into an act of criticism when the river started to become encased in aestheticized concrete. Thus, three years after we made our original proposal, we proposed a second question for the mayor and the city council, ‘Can it be that you have forgotten what a river is?’” 

A similar battle has played out in San Antonio, though over a much longer period of time. The dialogue that has emerged from the building and rebuilding of the river here — involving city planners, engineers, architects, artists, environmentalists and others — brings into focus how thorny the question “What is a river?” can really become. 

The entire modern history of the river, from Robert Hugman’s 1929 proposal to the Works Progress Administration’s partial realization of his vision, to channelization in the 1950s, to the ongoing restoration of the Mission Reach today, is a story of competing answers to that question. Is the river a drainage system, a marketplace, a park, or a natural habitat? The River Oversight Committee (ROC), co-chaired by former mayor Lila Cockrell and architect Irby Hightower, ultimately decided that rather than committing to one singular vision, the river could embody an evolving conversation between these functions. 

The ROC grew out of the Mission Trails Oversight Committee in 1998, in response to city and county plans to add hike and bike trails along the San Antonio River south of downtown. Those plans left in place the straightened concrete channel built by the Army Corps of Engineers in the 1950s. The committee wanted something more natural. They wanted a place where wildlife could flourish and people could walk, boat or fish; a place with a wide variety of native plants; a meandering stream that would change from one year to the next. With this vision, they embarked on one of the largest ecological restoration projects ever attempted in an urban environment. 

It turns out that getting from a concrete channel to a variegated habitat equally welcoming to people and wildlife, which still controls flooding, requires extremely sophisticated engineering. Through an involved development process, in which the San Antonio River Authority (SARA) helped the ROC negotiate a design with the Army Corps of Engineers, a plan was born. As Hightower describes it, it is a plan that “accomplishes a lot more things, less perfectly” than a typical restoration. “An ideal ecological restoration would have no hike and bike trails, people wouldn’t get close to the water,” he points out. Competing requirements made the process “closer to design than traditional engineering, which is more of a straight-line approach.” 

When the ROC started their work, their vision was not well-formed, and it was through internet research by committee member Susan Hughes (now Executive Director of the Green Spaces Alliance) that they became aware of fluvial geomorphology — the study of how the land moves and changes over time in riverbeds. The Army Corps of Engineers only started looking seriously at ecology around the year 2000, but had developed software called HEC-RAS in 1995 to model water flow through river channels. 

The ROC asked the Corps to “armorize” the river as little as possible while still keeping potential flood damage to a minimum. In some locations, the river still required this armorization. On one short stretch where the river curves under highway 90, for instance, the banks are built of stones held in place by a wire mesh. Here, partly because of the curve in the river, and partly because the highway blocks sunlight, plants alone could not reliably prevent erosion during major flood events. 

The Corps has no mandate to design for recreational uses. But for the ROC, recreation is a key requirement of the project (if you look at the official Mission Reach logo, you’ll see a fisherman in the R). When the Corps presented initial plans, it was clear that personal watercraft — kayaks and canoes — could not pass through the weirs, which occur frequently in the river to help manage water levels. At the committee’s request, the engineers attempted to redesign the weirs to allow small boats to pass through narrow chutes. (This was not entirely successful, but SARA says they are working with another contractor to eventually retrofit the weirs and riffles along the river to accommodate small boats).

Jacobs Engineering was enlisted to help model the riverbed, including the placement of plants along the banks. Targeting both ecological and aesthetic requirements, Jacobs calculated GPS coordinates for 23,000 trees along the Mission Reach. Their aim was to meet the water and soil requirements of each plant and control erosion, while enhancing recreational activities (for example, thorny or fruiting plants would not be placed near walkways). SARA employees are responsible for planting each of these trees, which are being grown from seedlings. Thus, the project will not be “completed” for 50 years, as dozens of varieties of native plants slowly mature. 

No matter how sophisticated the software and deliberate the process, a river cannot be perfectly engineered. As Hightower points out, the plan that is being implemented is only a “good guess at what will work.” The designers knew this, and part of SARA’s job is to regularly survey quadrants of the Mission Reach so that the models can be re-run to evaluate water conveyance, plant maturation, and erosion over time. Depending on the results of further modeling, trees may be cut out or more may be planted, or less natural controls may be put in place. This further planning will be a discourse with the river itself, as it pushes soil and rocks from one place to another. 

After the first flood event following the restoration south of Lone Star Blvd, new riprap, including a thick, green plastic mesh had to be added to control erosion. As Hightower observes, this kind of mesh isn’t ideal for anyone. To the naturalists it looks jarringly unnatural, and to the engineers it won’t control water flow as well as the time-tested concrete channel. But the civic dialogue that has emerged around the river is in many ways as valuable as the public space itself. 

If someone were to walk from the top of the Museum Reach, along a pastoral walkway, carefully landscaped with public art around each bend, down into a bustling gauntlet of restaurants and bars, and then through a tree-lined historic neighborhood waterway, and out onto an open corridor of native plants and birds, that person would glimpse a conversation in which no genius was able to push aside all other views with his perfectly formed vision. 

At times we may regret that Robert Hugman was not given the respect of Frederick Law Olmsted, and was not able to see his vision realized on the scale of Central Park. And we may lament that the core River Walk has been given over too much to national chain restaurants — we may even agree with Scott Metzger’s sentiment that it has become a “strip mall on a river.” 

But if the discourse that has flowed through this city’s life for more than a hundred years continues to thrive in the River Oversight Committee, the San Antonio River Authority, the San Antonio River Foundation, and less formal groups of concerned citizens, it has the potential to embody a more vital expression of a city’s character than Olmsted’s pastoral masterpieces. It is a collaborative improvisation, started (perhaps) when city workers cut down some willow trees along the banks of the San Antonio River.