140 



TABLE IV.2.11.— MAJOR FLOW REGULATION STRUCTURES ON ESTUARINE-TERMINATING STREAMS— Continued 



Active 



storage 



State and River name Purpose volume 



PACIFIC NORTHWEST 



Oregon: 



Columbia-Dam and locks Navigation, power 87,000 



Willamette, locks. _ _ Navigation (i) 



Washington: 



White. Flood control 106,000 



Baker. Power 142,370 



Washington, Canada: Whatcom Municipal 26,400 



ALASKA 

 Alaska: 



Sour Mill Creek Desilting, industrial 150,000 



Purple Lake.. Power 25,000 



Annex Creek do 23,360 



Cooper Creek do 108,000 



Ekiutna Power, recreation 163,300 



PACIFIC ISLANDS 



Hawaii: Fresh water holding ditches... Water supply retention (i) 



1 No information available on volume. 



Reference: The National Estuarine Inventory. 



Data source: U.S. Geological Survey, U.S. Army Corps of Engineers. 



The Columbia River in Washington and Oregon is one of the most 

 fully developed large rivers in the country. This flow regulation 

 has had an impact on estuarine ecology, especially the anadromous 

 fish runs. There has been considerable modification in the estuarine 

 systems from freshwater flow regulation. Modification of the estuary 

 was not the primary objective of the regulatory projects but occurred 

 as an unsought consequence. Future water resource development 

 schemes will have to consider the estuarine impact to insure that 

 detrimental effects are kept at a minimum. 



Section 6. Summary 



The single great unique feature of the estuarine zone, which makes 

 it of primary importance to man and his civilization, is its role in 

 the life cycle of many animals which aid in converting solar energy 

 into more usable forms. Wliile no life form can be singled out as 

 irreplaceable, the kinds of life which need the estuarine zone to survive 

 represent essential links in the energy conversion chain upon whicfh 

 man depends for survival. 



Many of the uses cataloged in this chapter occur only because the 

 historical growth of the country makes the estuarine zone the place 

 where people and industry are. Only commercial navigation, naval 

 use, and commercial fishing are uses which are primarily associated 

 with the estuarine zone, rather than other parts of man's environment. 

 Uses such as water supply, waste disposal, and recreation are associ- 

 ated with civilization wherever it exists; in the estuarine zone they 

 may have different values, different emphasis, or different impact on 

 the biophysical environment. 



This chapter points out the intrinsic importance of the estuarine 

 zone as a feature of the human environment. The mere cataloging 

 of uses gives no measure of the total value of the estuarine environment 

 to man and his civilization, because each identifiable use is merely 



