Summary 



On August 2, 1956, the Governments 

 of Canada and the United States referred 

 to the International Joint Conimission 

 the responsibility for an investigation 

 to determine the feasibility, desirability, 

 and cost of developing hydroelectric power 

 in Passamaquoddy and Cobscook Bays 

 from tidal forces. On October 3, 1956, 

 an International Passamaquoddy Fisheries 

 Board was established and was given the 

 following reference: "to study specifi- 

 cally the effects which the construction, 

 maintenance, and operation of the tidal 

 power structure proposed might have 

 upon the fisheries in the Area" (cf. 

 I.J.C. Docket 72, October 3, 1956). 



A research committee composed of 

 Canadian and United States scientists 

 carried out oceanographic, biologic, and 

 economic investigations in the Passama- 

 quoddy area of southern New Brunswick 

 and eastern Maine. Most of the work 

 was done in the Quoddy Region which 

 includes all of the area inside the line 

 from Point Lepreau, N. B., to Northern 

 Head, Grand Manan, N. B., thence to 

 West Quoddy Head, Maine. The results 

 of the investigations provide a basis for 

 predicting the effects of the project on 

 the fisheries. 



It is expected that the construction of 

 dams will change the oceanographic fea- 

 tures of the Quoddy Region. Major changes 

 are anticipated inside Passannaquoddy and 

 Cobscook Bays and immediately outside 

 the dams. Effects outside the Head Har- 

 bour-Bliss Island line will likely be insig- 

 nificant. 



The mean water level of Passamaquoddy 

 Bay will be raised about 6 feet while 

 the mean level of Cobscook Bay will be 

 lowered about 5 feet. The mean "tidal" 

 range in the high pool and low pool will 

 be reduced to approximately 4 feet and 

 8 feet respectively. The tidal range of 

 the Bay of Fundy may Increase approxi- 

 mately 1 percent with a maximum In- 

 crease at the head of this Bay of less 

 than 1 foot. 



Current patterns In Passamaquoddy and 

 Cobscook Bays and In the approaches 

 will be altered markedly since the empty- 

 ing and filling gates will be closed for 



about 9 and 9^ hours respectively during 

 each tidal cycle of 12^ hours. When 

 the gates are open, velocities in 

 most areas should be only slightly lower 

 than at present. The residual counter- 

 clockwise circulation In Passamaquoddy 

 Bay will likely be more pronoionced. 

 Tidal streams In the outer Quoddy Region 

 will probably be altered by not more 

 than 20 percent. No change In nontldal 

 circulation Is anticipated for the Bay of 

 Fundy. 



Reduced velocities In Passamaquoddy 

 and Cobscook Bays will result In de- 

 creased vertical mixing, giving rise to 

 Increased stratification and hence to 

 greater seasonal variations In surface- 

 water temperature. The summer maxi- 

 mum Is likely to be In the vicinity of 

 68° F. while In winter an Ice cover Is 

 expected over part of the Bays. Outside, 

 little change Is expected adjacent to the 

 emptying and filling gates where there 

 will be slightly greater seasonal varia- 

 tion. 



Mean surface salinities for both pools 

 will be lowered but bottom salinities 

 are likely to be altered only slightly. 

 It Is doubtful If fresh water will pene- 

 trate below 30 to 50 feet. Flushing time 

 Is expected to Increase substantially. 

 Outside, no significant change Is expected 

 except near the emptying gates where 

 there will be a slight reduction in salinity. 



Oxygen concentrations of the deep 

 water Inside the dams may be lowered 

 somewhat, especially during periods of 

 maximum fresh water discharge. How- 

 ever, It Is unlikely to fall below 50 

 percent saturation. 



The herring population Is produced 

 outside the Quoddy Region, probably off 

 southwest Nova Scotia. The general 

 abundance of herring In the Bay of Fundy 

 and the Gulf of Maine is unlikely to be 

 affected. 



Echo-sounder records show thatalarge 

 propiortion of herring are In the open 

 waters of Passamaquoddy Bay where no 

 fishing takes place. Tagging experiments 

 show that herring move freely throughout 

 the Quoddy Region during the fishing 



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