The rapid conversion of land to urban and suburban areas has profoundly altered how water flows during and following storm events, putting higher volumes of water and more pollutants into the nation's rivers, lakes, and estuaries. These changes have degraded water quality and habitat in virtually every urban stream system. The Clean Water Act regulatory framework for addressing sewage and industrial wastes is not well suited to the more difficult problem of stormwater discharges. This book calls for an entirely new permitting structure that would put authority and accountability for stormwater discharges at the municipal level. A number of additional actions, such as conserving natural areas, reducing hard surface cover (e.g., roads and parking lots), and retrofitting urban areas with features that hold and treat stormwater, are recommended.

Recently, environmental scientists have been required to perform a new type of assessment-ecological risk assessment. This is the first book that explains how to perform ecological risk assessments and gives assessors access to the full range of useful data, models, and conceptual approaches they need to perform an accurate assessment. It explains how ecological risk assessment relates to more familiar types of assessments. It also shows how to organize and conduct an ecological risk assessment, including defining the source, selecting endpoints, describing the relevant features of the receiving environment, estimating exposure, estimating effects, characterizing the risks, and interacting with the risk manager. Specific technical topics include finding and selecting toxicity data; statistical and mathematical models of effects on organisms, populations, and ecosystems; estimation of chemical fate parameters; modeling of chemical transport and fate; estimation of chemical uptake by organisms; and estimation, propagation, and presentation of uncertainty. Ecological Risk Assessment also covers conventional risk assessments, risk assessments for existing contamination, large scale problems, exotic organisms, and risk assessments based on environmental monitoring. Environmental assessors at regulatory agencies, consulting firms, industry, and government labs need this book for its approaches and methods for ecological risk assessment. Professors in ecology and other environmental sciences will find the book's practical preparation useful for classroom instruction. Environmental toxicologists and chemists will appreciate the discussion of the utility for risk assessment of particular toxicity tests and chemical determinations.