The projected trend of future development is based on current (1990+) urbanization as shown in Figure 16 and assumes no new conservation or regulatory guidelines or policies; it follows the current patterns of ongoing development.

The trend for 2010 shows significant increases and intensification of urbanization in the Temecula Valley region of Riverside County, especially along existing primary road networks. The major corridor of urban intensification illustrates the growing connectivity between the Temecula Valley urban area and Los Angeles to the north. Increasing urbanization of this corridor will act to further inhibit biological connectivity between the Cleveland National Forest and the Mount Palomar area. The projection also shows significant encroachment by rural residential development on orchard and vineyard areas in and around the Temecula area. The consequences of this sprawl are ecologically disastrous: the impacts upon regional connectivity and hydrology may be irreparable after this 2010 projection.

From 2010 to the year 2030, the Temecula Valley will continue to be the primary area of increasing urbanization. By 2030, this will be a heavily developed urban center, with a corridor of urbanization stretching north toward Los Angeles. Development along major road networks between Temecula and Murrietta will continue to increase dramatically, especially along north-south links. There also will be continuing encroachment upon vineyard, agricultural, and sage/chaparral areas by rural residential development. Figure 17 illustrates that by 2030, all of the region’s easily developable land will have been "urbanized."

Of approximately one million+ hectares in the region, 200,000 hectares were developed in 1990; 400,000 hectares are publicly owned and will remain so. The remaining land–approximately 450,000 hectares–is privately owned and available for development. If current plans are followed, about 60 percent of the private land will have been developed by 2030, leaving only 200,000 hectares of less-potentially-developable land for the far future.

Rural-residential development promises to consume the largest amount of private land by the year 2030. Its low density requires more space per dwelling relative to the denser single- and multi-family residential categories.

The environmental consequences of the trend are the same as those of prior experiments conducted within the research framework: a fragmented landscape, loss of critical habitat, increased fire risk, and major downstream flooding impacts.

An additional consequence of the trend and its assumed growth in population is an increased dependence on importation of water (Figure 18). Using current water consumption estimates, an additional 80,000 acre-feet of water must be provided for each phase of development–from now until 2010, and from 2010 to 2030. Clearly, such an increase in water demand would create the need for increased water importation and new infrastructure, such as storm water and sewage treatment facilities. Water management must be a key aspect of any future for the region.

As these trend projections show, allowing development to proceed in accord with current trends and patterns could accommodate projected population and land use demands, but it would have serious, harmful impacts on the landscapes of this region. The question is: Where to build and where not to build? What design strategies have the potential to shape development in such a way that the integrity of the region’s landscapes would be maintained?