Water-quality data-collection activities in Colorado and Ohio; Phase III, evaluation of existing data for use in assessing regional water-quality conditions and trends

Abstract

ForewordOne of the challenges faced by the Nation is the development of reliable information that will guide the protection of our water resources. That challenge is being addressed by Federal, State, interstate, and local waterresource agencies and by academic institutions. Many of these agencies are collecting water data for a host of purposes, including compliance with permits and water-supply standards; development of remediation plans for specific contamination problems; operational decisions on industrial, wastewater, or water-supply facilities; and research on water quality and quantity. Prominent is the need for information of regional and national scope on the status and causes of current water-quality conditions and trends. Without this information, policy decisions may be based on information from a few localized problems. Conversely, a lack of information may lead to a false sense that some problems do not exist. In the past two decades, billions of dollars have been spent on water-quality data-collection programs. However, only a small part of the data collected for these programs has been obtained specifically to assess the status, trends, and causes of ambient water-quality conditions at regional and national scales. In some instances, the utility of these data for present and future regional and national assessments is limited by such factors as the areal extent of the sampling network, frequency of sample collection, and the types of water-quality characteristics determined.Water-quality data collected for permits and for compliance and enforcement purposes constitute a sizable source of information that may be suitable for regional and national assessments. However, such data need to be carefully screened before use. The needs, uses, and types of water-quality data vary widely, and data collected for one purpose are not necessarily suitable for other purposes. In fact, the use of unsuitable data in regional or national assessments can be much worse than a lack of information because the use of such data can lead to incorrect conclusions having far-reaching consequences.Accordingly, the U.S. Geological Survey, with cooperation from other agencies and universities, has undertaken a three-phase study in Colorado and Ohio to determine the characteristics of existing Federal and other publicagency water-quality data-collection programs and to evaluate the suitability of the data bases from these programs for use in water-quality assessments of regional and national scope. This report describes results of the third and final phase of the study. This study does not imply that past and present data-collection programs have failed or are inappropriate for their intended purposes. The data from those programs may fully meet individual agency needs and fulfill their mandated requirements, yet may have only limited relevance to water-quality questions of regional and national scope.This study has depended considerably on cooperation and information from many Federal, State, regional, and local agencies and...

A spatially distributed model for assessment of the effects of changing land use and climate on urban stream quality

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