Letter of Transmittal 



Hon. Stewart L. Udall, Secretary 

 U.S. Department of the Interior 



This letter transmits the report of the National Technical Advisory Com- 

 mittee on Water Quality Criteria. The chairmen of the five Subcommittees are to 

 be commended for an excellent job in pulling together a mass of information and 

 coordinating the efforts of the members to complete the report by the requested 

 date of June 30, 1968. 



This volume constitutes the most comprehensive document on water quality 

 requirements to date, and as such, will be used as a basic reference by groups and 

 agencies engaged in water quality studies and standards setting activities. At the 

 same time, the Committee members and I wish to emphasize that this report is not 

 sufficiently conclusive or inclusive to serve as the only guide in determining water 

 quality criteria or requirements. Regional variations in climate, topography, 

 hvdrology, geology, and other factors must be considered in applying the criteria 

 offered by the Committee to the establishment of water quality standards in specific 

 localities. 



I would also like to note that the Committee members have occasionally 

 departed from the task of developing water quality criteria, with which you charged 

 them, to make recommendations which are more properly the province of regulatory 

 agency policy makers or designers of pollution abatement facilities. A few examples 

 are: 



1. A recommendation that all waters, except those adjacent to waste outfalls, 

 provide for the maintenance and production of fish. 



2. Recommendations of engineering design criteria for waste treatment plants. 



3. A recommendation that incineration replace ocean disposal of sludge solids. 



The tendency to consider broad issues of policy and design criteria was per- 

 haps inevitable. While the mission was directed at water quality requirements, it was 

 easy for the experts to wander and propose approaches that attempt to account for 

 uncertainties and disagreements concerning scientific criteria. It is to the great credit 

 of the chairmen that they were able to properly maintain primary attention on water 

 quality criteria rather than the other two major components of water quality stand- 

 ards — water use designations and implementation and enforcement plans. 



This report is as valuable for what it does not say as for what it does say. The 

 work of the Committee illuminates the fact that the unknowns still far exceed the 

 knowns in water quality requirements — even to the experts. Therefore, requirements 

 should be applied with the best of judgments. One of the most valuable aspects of 

 the Committee's work was the examination of research needs and the guidance 

 offered in such needs. A report of research needs is published as a separate docu- 

 ment. 



The FWPCA is grateful to the many participating organizations and individuals 

 who comprised the Committee. They are to be congratulated for their cooperation 

 and enthusiasm in this monumental task. 



Joe G. Moore, Jr. 

 Commissioner 



