The San Joaquin Valley will likely lose a considerable amount of farmland to urbanization over the next 40 years no matter what policies the region adopts. However, different policy scenarios can substantially reduce the amount of farmland loss, according to a new report that I helped prepare for the Public Policy Institute of California.

The report plays out four different scenarios for how the eight-county region will urbanize in order to accommodate a doubling of population - to about 7 million people - by 2040. The most likely scenario is that the amount of urbanized land will triple, from about 600,000 acres in 2000 to about 1.7 million acres in 2040, while the amount of agricultural land will be reduced by about 15%, from 5.7 million acres to about 4.9 million acres.

Based on a GIS urbanization model developed at the University of California, Santa Barbara, the scenarios were not meant to serve as realistic future alternatives. Rather, these speculative scenarios show how several different sets of broad policies might affect the region's growth. And while the scenarios described the geographical extent of urbanization, they did not seek to describe the texture or the character of new urban development.

The four alternatives were:

1. An “accommodating urban development” scenario, which assumed that the urban development patterns from 1940 to 2000 would be replicated from 2000 to 2040.

2. A “prime farmland conservation” scenario, which assumed that all land categorized as prime farmland by the Department of Conservation was protected but all other private land was available for development.

3. A “high-speed rail” scenario, which assumed that most development would occur within a 20-mile radius of the planned stops for the proposed high-speed rail line.

4. An “automobile-oriented managed growth” scenario, which assumed that most growth will cluster around a series of highway improvements, mostly on east-west corridors up and down the Valley.

All scenarios were based on the same population assumption - an increase from 3.3 million to slightly more than 7 million people, or about 116%.

Broadly speaking, the “accommodation” scenario showed that urbanization would quadruple, from 600,000 acres to about 2.4 million acres. The rail and automobile scenarios showed a tripling of urbanization, to between 1.7 million and 2 million acres. The farmland preservation scenario showed an increase in urbanization of 134%, to about 1.4 million acres - only slightly higher than the percentage of population increase.
Significant farmland loss would occur under all scenarios except farmland preservation. The “accommodation” scenario showed a loss of 1.5 million acres of farmland - 26%. The rail and auto scenarios showed losses of 800,000 to 1.1 million acres - 15% to 20%. The farmland preservation scenario preserved all prime farmland but showed a loss of almost half a million acres of non-prime farmland.

The scenarios had some different effects on the northern counties, which draw many Bay Area commuters, as opposed to the southern counties, which are still rooted in agriculture. The prime farmland scenario actually led to less urbanization in the “Bay spillover” counties, such as San Joaquin and Stanislaus, because they have more prime farmland. The high-speed rail scenario led to more urbanization in these counties because they are slated to have more rail stops than the other counties.

Perhaps the biggest surprise was that the auto-oriented scenario was similar, in the aggregate, to the rail scenario. In some cases, the auto-oriented model proved even easier on agriculture because the assumed transportation improvements drew development to the transportation corridors at fairly high densities. Furthermore, the high-speed rail scenario would cluster development around existing cities on Highway 99 - and, therefore, on prime farmland - while the auto scenario would disperse more development to the west, where there is less prime farmland.

We concluded that the San Joaquin Valley is not well prepared to deal with problems on a regional basis. We also raised questions about whether the urbanization scenarios would foster further urban and social decay in poor areas, especially in the southern agricultural counties.

The report, “Urban Development Futures in the San Joaquin Valley,” was written by Michael Teitz, a former UC Berkeley planning professor and a senior fellow at PPIC, along with Charles Dietzel, a Ph.D. student in the Department of Geography at UCSB, and myself. It is available at