In April 1992 the Foundation Eni Enrico Mattei organized a workshop on the regulation of nonpoint source pollution. This volume inc1udes the proceedings of that meeting, as well as additional original contributions, in an attempt to provide an overview of recent theoretical developments in the field. Research on the causes, consequences, and control of nonpoint source pol lution has been carried out over the last two decades. Interest in this subject has grown as a result of the increasing recognition of the insufficiency of traditional pollution control policies focused on the large scale, confined, and general ly predictable pollutant discharges. In fact, many contemporary problems are caused by the combined activities of small polluters, along with natural pro cesses, intermittent and unpredictable events, and often involve pollutants with complex environmental outcomes. Despite the progress made in understanding the nature and size of pollution from diffuse sources, the issue of regulation is still far from being system at ically and adequately addressed. This policy vacuum is partly attributable to the difficulty of adapting the traditional point source regulatory tool kit to the specific features of nonpoint source problems. Such features inc1ude the tech nical difficulty of identifying sources and measuring individual emissions, their variability over time and space, the role played by natural processes in detennin ing pollutant discharges at source and their ultimate impacts on the receiving environmental media.

In 1997, New York City adopted a mammoth watershed agreement to protect its drinking water and avoid filtration of its large upstate surface water supply. Shortly thereafter, the NRC began an analysis of the agreement's scientific validity. The resulting book finds New York City's watershed agreement to be a good template for proactive watershed management that, if properly implemented, will maintain high water quality. However, it cautions that the agreement is not a guarantee of permanent filtration avoidance because of changing regulations, uncertainties regarding pollution sources, advances in treatment technologies, and natural variations in watershed conditions. The book recommends that New York City place its highest priority on pathogenic microorganisms in the watershed and direct its resources toward improving methods for detecting pathogens, understanding pathogen transport and fate, and demonstrating that best management practices will remove pathogens. Other recommendations, which are broadly applicable to surface water supplies across the country, target buffer zones, stormwater management, water quality monitoring, and effluent trading.

Abstract: The purpose of this study was to design a regulatory policy to solve a nonpoint source (NPS) water pollution problem, . Cost-sharing programs of various kinds have dominated NPS policy since the 19802s. However, such programs are neither efficient nor effective. Economists agree that, in principle, performance-based approaches are preferred to design-based, because they allow firms to choose least-cost abatement practices. However, nonpoint sources are seldom included in performance-based programs since it is very costly to monitor the performance of individual NPS polluters. The NPS pollution problem can be modeled as a generalized principal-agents problem. That is, the principal has to regulate agents while he cannot observe either the types and or the effort level of the agents; only total level of ambient pollution is verifiable. However this kind of problem is very complicated and a general solution has yet to be derived. Simplified models (with either only adverse selection, or hidden action) have been analyzed and first best solutions derived. Nevertheless, these solutions are incomplete, since they fail to solve simultaneously the adverse selection and moral hazard problems. I show that under assumptions consistent with the NPS pollution situation it is possible to decompose the generalized principal-agent problem into two univariate variational problems in the multi-agents case, and to design a two-step contract that solves both the adverse selection and the hidden action problems. I offer a policy-maker2s algorithm that can be used to design a regulatory policy to control NPS pollution. Three steps of a transaction 6 property rights/initial endowment assignment, price and quantity determination, and money/product exchange 6 are considered sequentially; an optimal regulatory intervention is chosen for each step; and then the whole policy is evaluated for consistency and for as-yet-unexamined effects on related markets. Inconsistencies and undesired general equilibrium effects are resolved by modifying the intervention at the appropriate step and re-iterating through the policy algorithm. This research has resulted in contributions in three areas of economic theory: policy design, mechanism design (the generalized principal agent problem), and environmental economics (the nonpoint source water pollution problem).

Pollution control, a key component of U.S. environmental policy, has made important progress in recent decades. Yet important problems remain and there is need for improvement in the pollution control regulatory system. This book is the most extensive evaluation of that system ever produced. It reveals many strengths and accomplishments, but also illustrates serious shortcomings and the need for reform. The volume emerges from three years of research on a fragmented 'system' of institutions, statutes, and procedures that is often inefficient and ineffective, hobbled by misplaced priorities. Part I provides an in-depth description of this system, centered on the federal Environmental Protection Agency and the labyrinthine laws it must implement. The authors evaluate the federal legislation, administrative decisionmaking, and the state-federal division of labor that defines the system. Davies and Mazurek assess the effectiveness and efficiency of U.S. pollution control. They discuss the performance of U.S. laws and regulations in comparison with those of other nations, assess the ability of the U.S. pollution control system to meet future problems, and consider proposals for reform and repair. Within this far reaching analysis, they include criteria that are often overlooked by policymakers and analysts, including social values, equity, nonintrusiveness, and public participation.

Environmental problems in coastal ecosystems can sometimes be attributed to excess nutrients flowing from upstream watersheds into estuarine settings. This nutrient over-enrichment can result in toxic algal blooms, shellfish poisoning, coral reef destruction, and other harmful outcomes. All U.S. coasts show signs of nutrient over-enrichment, and scientists predict worsening problems in the years ahead. Clean Coastal Waters explains technical aspects of nutrient over-enrichment and proposes both immediate local action by coastal managers and a longer-term national strategy incorporating policy design, classification of affected sites, law and regulation, coordination, and communication. Highlighting the Gulf of Mexico's "Dead Zone," the Pfiesteria outbreak in a tributary of Chesapeake Bay, and other cases, the book explains how nutrients work in the environment, why nitrogen is important, how enrichment turns into over-enrichment, and why some environments are especially susceptible. Economic as well as ecological impacts are examined. In addressing abatement strategies, the committee discusses the importance of monitoring sites, developing useful models of over-enrichment, and setting water quality goals. The book also reviews voluntary programs, mandatory controls, tax incentives, and other policy options for reducing the flow of nutrients from agricultural operations and other sources.

Nonpoint source (NPS), common in agriculture, reaches the environment as runoff from a field, not output from a waste pipe. Its control and regulation are also different from other types of pollution that may seem more familiar.