thorough planning, the synthetic ecosystem developed by beach nourishment could result 

 in the establishment of permanent or temporary deepwater refuges in the borrow areas 

 offshore combined with restored beaches for recreation and natural community succession 

 inshore. Other bonus benefits could be anticipated as accompaniments. 



Organizations whose mission require modifying the environment have lately been on 

 the defensive. With intelligent multidisciplinary investigation beforehand, many 

 engineering modifications of the environment could be turned into positive environmental 

 enhancement programs. Such is the meaning of the term ecological engineering. 



In the course of dredging or filling for purposes other than beach nourishment, 

 consideration should be given to the chance for environmental improvement. This entails 

 viewing the specific engineering undertaking from all possible angles— going beyond the 

 strict initial purposes of the project to a total consideration of environmental, engineering, 

 and social aspects. 



Where navigation channels must be dredged and the spoil is not used for beach fill, spoil 

 areas might be located to improve the local conditions for little added cost. Such locations 

 would have to be carefully planned before starting the projects, and requirements specified 

 in advance. 



Use of ecological engineering offers exciting possibilities in connection with coastal 

 engineering. Principles of ecological engineering usually have not been applied to the 

 marine environment. 



Deepwater refuges, such as borrow pits furnish protection for concentration points of 

 many species of fish and shellfish. Effectiveness of these refuges depends on their relation 

 to the geographical, hydrographical, and ecological requirements of the organisms involved. 

 Establishment of such areas should be coordinated with commercial and sport fishing 

 interests. 



In many instances, such borrow refuges would be the natural result of normal 

 operations. In other instances, shght changes in the initial plans might increase the 

 effectiveness of the refuge. Truly effective ecological engineering would depend on the 

 studv of hydrographic conditions in local areas and of knowledge of fish and shellfish 

 habits and preferences in local waters before dredging. 



Sediment disturbances resulting from dredging can be advantageous in ecological 

 engineering, if planning and operations are properly carried out. Nutrients released by 

 dredging are valuable in the flow of energy and material (food) through a community as 

 emphasized by Cronin, Gunther, and Hopkins (1969). A natural consequence of proper 

 dredging would be stimulation of some or all aspects of community well-being. Further, 

 controlled or partly controlled release and direction of sediment loads could be used to 

 stimulate specific parts of the physical and biological community. 



However, Cronin, et al., (1969), warn of the dangers of possible release of harmful 

 substances as a result of stirring up of bottom deposits. Conceivably this could be properly 

 directed and controlled, depending on (a) the nature of the released substances, 



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