The Long Road To Saving a Watershed
By PETER BRAND
This sidebar is a supplement to The California Mirage
When I first started working in Ventura County as a project manager for California’s State Coastal Conservancy, our biggest concern was the rapid rate at which the area’s farmland was being developed. Los Angeles just over the hill to the south was poised to cover Ventura with the same kind of sprawl that had forever changed the L.A. landscape. Ventura’s ecosystems were relatively intact, however, at least as compared with the rest of southern California.
This created an important but potentially brief opportunity: if we could save Ventura’s farms, we might then be in a position to restore the natural water systems the region’s agricultural economy depended on.
To avoid making merely an emotional or philosophical appeal on this front, we commissioned an economic study. The report that resulted was called “The Value of Agriculture to Ventura County,” and it yielded some immediate surprises. It turns out that when judged by crop sales per acre, Ventura’s farmland was more valuable than any other county in California, at almost three times the state average. Given California’s outsized role as a global food supplier, this was big news. “Ventura County’s farmland,” the report concluded, “is some of the most productive in the world, both in yield and gross revenue.”
The economists were also asked to compare the area’s farmland revenue to the costs that county and city officials would incur if they allowed farmland to be developed for housing, according to prevailing trends. Those trends of course are precisely what have led to low-density suburban sprawl, instead of the higher density, more compact patterns of central city urbanization. Sure enough, extending city services of all kinds to sprawling suburbs was significantly more expensive than serving a densely growing city. To make fiscal matters worse, the sprawl would also eat away at the local agricultural economy.
Armed with this information, a coalition of agriculture leaders and elected officials put an initiative on the county ballot to create urban growth limit lines. Entitled “Save Our Agricultural Resources” (or SOAR). The initiative passed, and proved so popular that in November, 2016, Ventura voters enthusiastically extended its restrictions to 2050.
Now that the cities and farmers were no longer competing with each other over land, they still had to contend with the future of the Santa Clara River—the dominant natural force in the region. The river happens to be one of the flashiest river systems in the west, and perhaps in the world. While it usually flows at a placid 150 cubic feet per second (cfs), in a storm that can change quickly. Our hydrologists discovered flood data from 1992 that documented flows rising from about 2,000 cfs to 104,000 cfs, then back down again within a 24-hour period.
Rivers with this kind of force pose huge challenges to farmers–not only of lost seasonal crops but also lost citrus orchards that were nurtured for many years. The flooding cost was borne by the farmers and, downstream, by the cities and the flood control district. But if we allowed flooding of the historic floodplain and restored much of that riverine habitat we could spread out and slow down the floods. The result would be less damage, and more recharge of the aquifers. Wherever possible, we would remove levees that were no longer needed or set them back to the new edge shared by habitat and farms.
To launch this initiative, we proposed a purchase of the Santa Clara River corridor—the active floodway plus as much of the adjacent habitat area as farmers were willing to sell. Many of them saw the wisdom of the plan and stepped forward right away. We—that is, the State Coastal Conservancy through its partner the Nature Conservancy, using $30 million from SCC bonds, and other government funding—have now bought 19 miles of river corridor, and approximately 4,000 acres adjacent to it. We’ve also been dedicated an additional 7 miles by an upstream landowner. A trail for the public will ultimately follow the river 35 miles down to the sea.
All of this was just step one, however. Our goal now was to paint a convincing picture for the public of the grandeur of this region, as it was and as it could be with full restoration. To accomplish this, we turned to experts in a relatively new science called “historical ecology.” This team, led by Robin Grossinger of the San Francisco Estuary Institute, included scientists, historians, and cartographers, who tracked down every historical source they could find—from the barely legible stories and pictures drawn in the notebooks of explorers to remote sensing maps using the latest visioning technology.
After assembling oral histories, old black and white aerial photos, and drawings, these eco-historians drew an entirely new set of maps of the area’s habitat vegetation patterns and “geomorphology” (i.e. how natural forces had shaped the landscape over time). Each source was vetted and ranked for its “confidence level” to map what the landscape used to be in Ventura before settlement. All of the old maps were “georectified” to make sure their locations were accurate, and therefore usable.
Drawing on 19th-century survey maps they found in the National Archives in Washington, D.C., the researchers mapped a broad network of wetlands, covering the territory where San Diego, Orange County, and Los Angeles now lie. Many of these wetlands were gone but some had been spared. Amazingly, two coastal wetlands that survived proved to be unique remnants of ecosystem “archetypes”—in other words, the last of their kind. Both were endangered, and both lie in Ventura County.
An important outcome of the Historical Ecology study was the creation of a deep approach to restoration design. As the historical ecologists gathered their information, we brought them in to meet with SCC river and wetland restoration designers, in an effort to shape and in some cases reshape their thinking on the Santa Clara River restoration plan, and another area nearby. Without this level of knowledge, our scientists would have been extrapolating solutions onto a blank canvas obscured by 20th century farming practices.
When we finally presented our material, Ventura residents were able, for the first time, to picture what used to flow and grow beneath their feet, and under their streets, and to know for the first time what had been lost. The history that we had mapped for the Santa Clara River floodplain showed the full extent of its old groundwater recharge zone, highlighting the importance of what are called “paleo-channels”—underground streams that fed the rich, alluvial Oxnard Plain at the river’s basin. That information strengthened Ventura citizens’ imagination, and their resolve.
As our restoration efforts took hold, the farmers no longer had to compete with the cities for land. And if they ceded some of their cropland back to the rivers, both the cities and the farmers realized they would reduce their flooding costs. Meanwhile, local rivers could replenish the aquifers everyone depended on. Now, when people start wringing their hands again about the seeming eternity of California’s drought, Ventura’s farmers might find something other than silt at the bottom of their wells.