nels, and the term 'estuary' means all or part of the mouth of a navi- 

 gable or interstate river or stream or other body of water having un- 

 impaired natural connection with open sea and within which the sea 

 water is measurably diluted with fresh water derived from land 

 drainage." 



Explicitly included in these definitions is all of the strip of land and 

 water where the continent and the islands meet the sea, except those 

 few stretches of coast where there are no embayments and where there 

 is no land runoff. Yet even these have already felt the impact of the 

 expanding socioeconomic environment, as the recent oil well blowout 

 o& Santa Barbara, Calif., demonstrated. 



Implicit in the study directive is the charge to develop a program 

 to protect the Nation's coastal land and water resources from the im- 

 pact of pollution, and other disruptive pressures of the expanding 

 social and economic environment, in the coastal region of the Nation. 

 The investigations of this study and the recommendations presented 

 in this report therefore include consideration of man's impact on the 

 entire coastal environment, whether it occurs in a bay, marsh, or 

 along an ocean beach. 



The term ^^estuarine sone,''^ as used in this report, refers to the geo- 

 graphic zone including the coastal counties between the landivard limit 

 of tidal influence and the 3-mile limit to seaward. Nevertheless, the true 

 limits of the estuarine zone differ for each of the three major environ- 

 mental systems that make up the estuarine environment. The dissimi- 

 larity between the definition and the actual zone of influence of the 

 estuarine zone constitutes one of the major problems a national estu- 

 arine management program faces. 



The natural estuarine environment extends from the landward limit 

 of tidal influence to the measurable seaward effect of fresh water run- 

 off. This may vary in width from a few yards off some parts of the Cali- 

 fornia coast to 50 miles off the Mississippi Delta. 



The geographic range of the social and economic estuarine environ- 

 ment, the user's world, depends solely on man's ability and need to get 

 to and use the estuarine environment. In terms of direct use, everything 

 between the head of navigation landward and in sight of land seaward 

 would be included. 



The limits of the estuarine institutional environment are those of the 

 political subdivisions that include parts of the estuarine zone. This 

 includes the 274 coastal counties, the 24 coastal States, the Territories, 

 the District of Columbia, a variety of interstate compacts and commis- 

 sions, and the Federal Government. 



The landward and seaward limits of the estuarine zone used in this 

 study were set for the purposes of collecting and analyzing information 

 pertinent to the study. The limits do not suggest that this zone can 

 be isolated from either the upland rivers or the ocean, nor that this 

 zone can be managed effectively without recognizing the problems in 

 these and other environments. 



The National Estuarine Pollution Study 



The congressional assignment to the Secretary of the Interior was 

 delegated to the Federal Water Pollution Control Administration. 

 The Administration established an Office of Estuarine Studies (now 



