An interviewer once asked the celebrated designer Charles Eames how he dealt with the issue of accepting compromises in his work. "I have never been forced to accept compromises," Eames replied, "but I have willingly accepted constraints." The answer is a subtle, even wily, one; it's the kind of statement whose truth slowly creeps on you and changes the way you think. Eames, in effect, issued a challenge to all designers to regard constraints not as forces that erode design, but as the very essence of design itself. It is hard to imagine a more constrained place in which to build a residential community than in the proposed Rio Vista subdivision in Cathedral City, a small town in Riverside County not far from Palm Springs. Constrained, because the climate in Cathedral City is as harsh as can be found in Southern California: temperatures can rise to 120 degrees at the height of summer. A stone's throw from a freeway and the Southern Pacific railroad, Rio Vista can also be noisy. The area is subject to sandstorms that can pile up mounds of sand like snowdrifts in Vermont. And the area is a flood plain, where detention ponds are necessary to contain the fury of 100-year floods. Another set of constraints on Rio Vista, arguably of a more positive kind, are the Ahwahnee Principles, which the city has adopted as part of its general plan. Framed by a group of designers that included Peter Calthorpe, Andres Duany, Elizabeth Plater-Zyberk and Stefanos Polyzoides, the Ahwanee Principles are the Decalogue of the New Urbanism. This brief document sets forth the worthy and by-now-familiar tenets of the new thinking in urban design, including the desirability of walkable streets with slow-moving cars, oriented around community centers and transit stations that can easily be reached by foot. The principles also emphasize a "comprehensive" community that includes employment centers as well as housing for people with differing scales of income. Too often, the New Urbanism is responsible for — or has been used as window dressing for — developments that are little more than exercises in nostalgia. Some New Urbanist developments are not site-specific, and do not reflect in their design the climate, or culture or regional nature of the locale. In the case of Rio Vista, however, the site planning firm, Warkentin Partnership, had little choice but to respond to local conditions. That's fine by principal Bill Warkentin, who said he is opposed to the sort of subdivisions that "look as if they could have been built anywhere." Although still in a preliminary phase, Warkentin's scheme for Rio Vista is notable for not being a cookie-cutter product. In point after point, the master plan attempts to address the realities of the site, and, where possible, to use them as the basis positive design features than enhance the quality of life. A good example is the way that the site plan handles the flood retention basins that traverse the middle of the plan. Measuring 100 feet across and eight feet deep, these basins are too narrow for conventional parks and ball fields. Warkentin makes the flood basins into virtues by making them the scenic median of the area's main drag, Rio Vista Boulevard, which is split into two single-directional roads with the basin in between. The basin itself is beautified with xeriscape planting, and activated with hiking trails and exercise equipment. Another environmental accommodation that harmonizes well with the Ahwahnee agenda are Warkentin's plans to plant the residential streets mesquite trees. As a desert native that does not require watering, the tree works well in Cathedral City. The canopy of the mesquite allows some light to filter through, so a future arbor formed of mesquite canopies meeting above the street does not promise to be a dark place but a (comparatively) cool street of dappled light — a pleasant idea that encourages walking in otherwise unbearable heat. In accordance with Ahwahnee, the plan features a neighborhood commercial center that parallels the freeway, a four-acre park that may someday contain a "swimming lagoon," a traffic circle that slows down cars and serves as an excuse for a three-acre park in its interior. Inventively, the designers have also provided eight small "pocket parks," and arranged them, in sets of four, on the Four Corners of an intersection. Bunching up the parks in this way makes them appear larger, while maximizing the impact of the green space on the street. Yet another refreshing accommodation to climate is a set of schematic suggestions for housing design. (Arranged in six "villages," Rio Vista would contain up to 1,392 dwelling units, of which 1,000 would be single-family homes.) Although the houses are not yet designed — those designs would probably be commissioned by the merchant builders who buy into Rio Vista — Warkentin has created an intriguing set of guidelines for residential architecture. Unlike nearly all the new housing in Las Vegas, for example, which is based on housing in Southern California and is entirely unsuitable for the desert, Warkentin has proposed a prototype house that responds to the climate both in its orientation perpendicular to breezes, as well as through design features that emphasize passive solar heating and cooling. In addition to the abbreviated front yard, with a short fence for privacy, Warkentin has proposed shading outdoor living areas with "brises soleil," or walls that admit only a small amount of light through narrow windows or shutters; the walls, of course, provide some protection from the region's blowing sand. In accordance with Ahwahnee, the plan encourages, but does not require, the use of rear-loaded alleys. (Warkentin also suggested that four houses could be pulled together so that their respective patios could together form one large courtyard — a worthwhile idea for maximizing shaded outdoor space in which children could play.) Some of the environmental mitigations at Rio Vista do not sound particularly picturesque, such as a 15-foot soundwall that would block the noise from the freeway. And a set of fences that would be located along a wash just west of the project (not shown on the map) would make use of barricades, not unlike snow fences, which can shield the community from blowing sand. Those examples aside, Rio Vista is impressive for the inventions of the designers that takes pragmatic protections against heat and wind and sand and monsoon-strength flood, and turns them to good advantage as attractive elements of a New Urbanist plan. As the project remains unbuilt, I obviously reserve final judgment. But much credit must be given to Warkentin for making so many silk purses out of the environmental sow's ear of Rio Vista. The big lesson of Rio Vista is that Ahwanee/New Urbanist approach may turn out to be workable and useful in an extreme climate with many environmental constraints. To some people, such a conclusion might seem obvious. But as mentioned earlier, New Urbanist developers have not always opened their eyes to their surroundings and let the environment participate in the design. Ironically or not, the many constraints on Rio Vista may help make this desert subdivision a more livable place than in some subdivisions in much milder climates.