Tehran, the capital of the Islamic Republic of Iran, is a case of unplanned urban development. About 12% of Iranians are Tehran dwellers, and geology plays a major role in their environment. The city is located in northern Iran in the foothills of the Alborz Mountains. Sediments underlying the city are composed of coarse (northern part of Tehran) to very fine (southern part of Tehran) sandstone, siltstone, and mudstone with interbeds of gravels and pebbles in various proportions up to a depth of 1600 m. The early settlers were attracted to the area because there were bountiful springs and kanats (or qanats, an underground channel with vertical access shafts used to transport water from an aquifer under a hill to the surface without the need for pumping). The inharmonious geomorphology has strongly influenced the local climate for Tehran, with northern portions of the city in the humid mountains and southern portions in the desert. As development and expansion of the urban area continue, there will be increasing demand for natural resources and services such as water supply and construction material, land-use changes, increasing pollution, and exposure to geological hazards. In this article, we use surface and subsurface geological data to highlight the geological constraints on sustainable urban growth and management.

Disaster risk reduction efforts are lacking in many hazard-prone areas around the globe. Governmental initiatives in El Salvador sought to address challenges to disaster management that became evident following a series of disasters spanning 1998–2005. The region surrounding San Vicente volcano, El Salvador, has a history of disasters but, until recently, has received little attention toward hazard mitigation. The debrisflow disaster in November 2009, triggered by rains from Hurricane Ida, was the first time new systems were tested, and an in-depth review of the evolution of these systems is the focus of this paper. Faculty at the Universidad de El Salvador–Facultad Multi-disciplinaria Paracentral (UES-FMP), in San Vicente experienced the tragedy first-hand and perceived that chaotic project implementation, redundant objectives among various groups, and poor coordination hindered the effectiveness of postevent disaster risk reduction efforts. Poor potential-hazard awareness, no warning or monitoring systems, and unclear crisis-response responsibilities all contributed to >200 deaths in the region. UES-FMP agricultural sciences faculty led a comprehensive effort to identify weaknesses and improve plans for the next catastrophe. Their approach encompassed conceiving and implementing new research, field, and training activities for improving hazard understanding and communication in order to inform decision makers and the public. UES-FMP partnered with research and development groups to gather hydrometeorological data, model hazards, and train local stakeholders. UES-FMP encourages disaster risk reduction practitioners to focus on interdisciplinary methods to help guide project design. Experiences from San Vicente can be applied to improve disaster risk reduction and hazard research efforts in other areas.

Shallow landslides are significant natural hazards in Oregon, and identification of areas susceptible to future landslides is a critical step in reducing risk. Recent advances in identification of areas susceptible to shallow landslides are mostly based on geographic information system (GIS) calculations of the slope stability using the infinite slope equation. This technique was further improved with high-resolution light detection and ranging (LiDAR)–based digital elevation models (DEM) converted to very accurate slope data as input into the GIS models. However, these models still underestimate and overestimate the susceptibility in certain areas compared to past landslide events and field observations. One significant overestimation we noted occurs in regionally flat areas with isolated steep slopes that have very little relief. We developed a method to remove these isolated overestimated areas using a neighborhood analysis with a maximum relief of 1.22 m (4 ft). Because landslides that originate on the steep slope may extend back into the flat area above the slope, or out onto the flat area at the toe of the slope, we applied a 9 m (30 ft) buffer (twice our defined depth to failure for shallow landslides) for all of the areas with a calculated factor of safety (FOS) less than 1.5. We tested the methods on three landslide inventory databases examining two main criteria: (1) capture rate (overall and individual landslides) and (2) reduction in total map area susceptibility coverage while maintaining a high capture rate. We found the two methods maintained a capture rate between 90% and 99% while at the same time reducing the total map area susceptibility zones from 64% to 42%.

We reviewed the current state of waste management practices in Nigeria using examples from different parts of the country. Commonly practiced waste disposal methods in Nigeria, such as burial, open-air burning, and open dumping, were found to be ineffective and detrimental to public health and the environment. It was also shown that waste management cannot be successfully operated as a social service. Rather, the generator of waste must be held responsible. Problems confronting efficient waste management in Nigeria include the proliferation of unplanned settlements, traffic congestion, insecurity, and ignorance. An experimental model being used in Lagos State for the management of wastes may be the solution. Given the rate of population growth, industrialization, and urbanization, forward-looking and effective waste management plans need to be set in motion for the protection of public health. Such plans must involve all stakeholders, including the waste generators, the private sector, the informal sector, and regulatory agencies.

Abstract Developments in Engineering Geology is a showcase of the diversity in the science and practice of engineering geology. All branches of geology are applicable to solving engineering problems and this presents a wide frontier of scientific opportunity to engineering geology. In practice, diversity represents a different set of challenges with the distinctive character of the profession derived from the crossover between the disciplines of geology and engineering. This book emphasizes the importance of understanding the geological science behind the engineering behaviour of a soil or rock. It also highlights a continuing expansion in the practice areas of engineering geology and illustrates how this is opening new frontiers to the profession thereby introducing new knowledge and technology across a range of applications. This is initiating an evolution in the way geology is modelled in engineering, geohazard and environmental studies in modern and traditional areas of engineering geology.

Abstract The natural landscape of the North Shore of Vancouver is a mountainous one extending from sea level to ~1400 m. Land below ~400 m has been undergoing increasing urbanization since the 1950s. Development has encroached on areas subject to natural hazards such as floods, debris flows, slope failures, and coastal inundation. We will visit examples of these urban hazards, discuss problems of hazard identification in a forested landscape, and review urban planning and engineering responses to hazard management.