The modern southwestern cities of Phoenix, Tucson, Las Vegas, Albuquerque, and El Paso occupy lands that once supported rich desert ecosystems. Typical development activities often resulted in scraping these desert lands of an ancient living landscape, to be replaced with one that is human-made and dependent on a large consumption of energy and natural resources. Design with the Desert: Conservation and Sustainable Development explores the natural and built environment of the American Southwest and introduces development tools for shaping the future of the region in a more sustainable way. Explore the Desert Landscape and Ecology This transdisciplinary collaboration draws on insights from leading authorities in their fields, spanning science, ecology, planning, landscape development, architecture, and urban design. Organized into five parts, the book begins by introducing the physical aspects of the desert realm: the land, geology, water, and climate. The second part deals with the "living" and ecological aspects, from plants and animals to ecosystems. The third part, on planning in the desert, covers the ecological and social issues surrounding water, natural resource planning, and community development. Bring the Desert into the City The fourth part looks at how to bring nature into the built environment through the use of native plants, the creation of habitats for nature in urban settings, and the design of buildings, communities, and projects that create life. The final part of the book focuses on urban sustainability and how to design urban systems that provide a secure future for community development. Topics include water security, sustainable building practices, and bold architecture and community designs. Design Solutions That Work with the Local Environment This book will inspire discussion and contemplation for anyone interested in desert development, from developers and environmentalists to planners, community leaders, and those who live in desert regions. Throughout this volume, the contributors present solutions to help promote ecological balance between nature and the built environment in the American Southwest-and offer valuable insights for other ecologically fragile regions around the world.

A reconnaissance of 36 tributaries of the Colorado River indicates that debris flows are a major process by which sediment is transported to the Colorado River in Grand Canyon National Park. Debris flows are slurries of sediment and water that have a water content of less than about 40 percent by volume. Debris flows occur frequently in arid and semiarid regions. Slope failures commonly trigger debris flows, which can originate from any rock formation in the Grand Canyon. The largest and most frequent flows originate from the Permian Hermit Shale, the underlying Esplanade Sandstone of the Supai Group, and other formations of the Permian and Pennsylvanian Supai Group. Debris flows also occur in the Cambrian Muav Limestone and underlying Bright Angel Shale and the Quaternary basalts in the western Grand Canyon. Debris-flow frequency and magnitude were studied in detail in the Lava-Chuar Creek drainage at Colorado River mile 65.5; in the Monument Creek drainage at mile 93.5; and in the Crystal Creek drainage at mile 98.2. Debris flows have reached the Colorado River on an average of once every 20 to 30 years in the Lava-Chuar Creek drainage since about 1916. Two debris flows have reached the Colorado River in the last 25 years in Monument Creek. The Crystal Creek drainage has had an average of one debris flow reaching the Colorado River every 50 years, although the debris flow of 1966 has been the only flow that reached the Colorado River since 1900. Debris flows may actually reach the Colorado River more frequently in these drainages because evidence for all debris flows may not have been preserved in the channel-margin stratigraphy. Discharges were estimated for the peak flow of three debris flows that reached the Colorado River. The debris flow of 1966 in the Lava-Chuar Creek drainage had an estimated discharge of 4,000 cubic feet per second. The debris flow of 1984 in the Monument Creek drainage had a discharge estimated between 3,600 and 4,200 cubic feet per second. The debris flow of 1966 in the Crystal Creek drainage had a discharge estimated between 9,200 and 14,000 cubic feet per second. Determination of the effective cross-sectional area was a problem in all calculations involving superelevations on bends because areas near superelevation marks were 1.5 to 3.5 times larger than areas of upstream or downstream cross sections. Debris flows in the Grand Canyon generally are composed of 10 to 40 percent sand by weight and may represent a significant source of beach-building sand along the Colorado River. The particle-size distributions are very poorly sorted and the largest transported boulders were in the Crystal Creek drainage. The large boulders transported into the Colorado River by debris flows create or change hydraulic controls (rapids); these controls appear to be governed by the magnitude and frequency of tributary-flow events and the history of discharges on the Colorado River. Reworking of debris fans by the Colorado River creates debris bars that constrain the size of eddy systems and forms secondary rapids and riffles below tributary mouths.

Photographs made in Grand Canyon a century ago may provide us today with a sense of history; photographs made a century later from the same vantage points give us a more precise picture of change in this seemingly timeless place. Between 1889 and 1890, Robert Brewster Stanton made photographs every 1-2 miles through the river corridor for the purpose of planning a water-level railroad route and produced the largest collection of photographs of the Colorado River at one point in time. Robert Webb, a USGS hydrologist conducting research on debris flows in the Canyon, obtained the photographs and from 1989 to 1995 replicated all 445 of the views captured by Stanton, matching as closely as possible the original camera positions and lighting conditions. Grand Canyon, a Century of Change assembles the most dramatic of these paired photographs to demonstrate both the persistence of nature and the presence of humanity. Unexpected longevity of some plant species, effects of animal grazing, and expansion of cacti are all captured by the replicate photographs. More telling is evidence of the impact of Glen Canyon Dam: increased riparian vegetation, new marshes, aggraded debris fans, and eroded sand bars. In the accompanying text, Webb provides a thorough analysis of what each pair of photographs shows and places the project in its historical context. Complementing his narrative are six sidebar articles by authorities on Canyon natural history that further attest to a century of change. The level of detail obtained from the photographs represents one of the most extensive long-term monitoring efforts ever conducted in a national park; it is the most detailed documentation effort ever performed using repeat photography. Much more than simply a picture book, Grand Canyon, a Century of Change is an environmental history of the river corridor, a fascinating book that clearly shows the impact of human influence on Grand Canyon and warns us that its future is very much in our hands.

The modern southwestern cities of Phoenix, Tucson, Las Vegas, Albuquerque, and El Paso occupy lands that once supported rich desert ecosystems. Typical development activities often resulted in scraping these desert lands of an ancient living landscape, to be replaced with one that is human-made and dependent on a large consumption of energy and natural resources. Design with the Desert: Conservation and Sustainable Development explores the natural and built environment of the American Southwest and introduces development tools for shaping the future of the region in a more sustainable way. Explore the Desert Landscape and Ecology This transdisciplinary collaboration draws on insights from leading authorities in their fields, spanning science, ecology, planning, landscape development, architecture, and urban design. Organized into five parts, the book begins by introducing the physical aspects of the desert realm: the land, geology, water, and climate. The second part deals with the "living" and ecological aspects, from plants and animals to ecosystems. The third part, on planning in the desert, covers the ecological and social issues surrounding water, natural resource planning, and community development. Bring the Desert into the City The fourth part looks at how to bring nature into the built environment through the use of native plants, the creation of habitats for nature in urban settings, and the design of buildings, communities, and projects that create life. The final part of the book focuses on urban sustainability and how to design urban systems that provide a secure future for community development. Topics include water security, sustainable building practices, and bold architecture and community designs. Design Solutions That Work with the Local Environment This book will inspire discussion and contemplation for anyone interested in desert development, from developers and environmentalists to planners, community leaders, and those who live in desert regions. Throughout this volume, the contributors present solutions to help promote ecological balance between nature and the built environment in the American Southwest-and offer valuable insights for other ecologically fragile regions around the world.