The construction of channel improvements and by-pass channels has been 

 undertaken on several rivers. Such channelization may consist of widening, 

 deepening and straightening the existing channel, or it may involve a diversion 

 capable of carrying the entire flood flow of a river through a hazardous area. 

 Examples of channel improvement may be seen in the work of the Metropolitan 

 Toronto and Region Conservation Authority on the Humber River at Weston, 

 on Black Creek near Jane Street, and on the Don River at Hoggs' Hollow. 

 Channel improvement work on the Thames River has been carried out at 

 Mitchell and Ingersoll by the Upper Thames River Conservation Authority. 



A channel diversion was made at Brampton where the Etobicoke Creek 

 formerly passed under the main street of that town through a covered channel. 

 The original channel with its limited capacity, was unable to handle the heavy 

 spring flows through the business section of the town which was frequently 

 severely damaged. The construction of the diversion in 1949 and 1950, by the 

 former Etobicoke-Mimico Conservation Authority (now part of the Metropolitan 

 Toronto and Region Conservation Authority) cost $976,000. This channel car- 

 ries flood water safely around the low-lying centre of the Town, and it has 

 already saved more than its cost on at least two occasions. The channel is 

 concrete-lined, 3,100 feet in length, with a 30-foot bottom width, and is de- 

 signed to carry 3,500 cubic feet per second, although it safely discharged much 

 more than this at the time of Hurricane "Hazel" in 1954. 



Dikes and flood walls are additional man-made encroachments on a flood 

 plain which, while giving protection, tend to further increase peak flow stages. 

 Their construction is only recommended when valuable property is concentrated 

 in a flood hazard area. Among the many municipalities which have parts pro- 

 tected by dikes are: London, Brantford, Paris, Walkerton, Bridgeport, Chatham, 

 Ingersoll and St. Mary's. 



Channel improvements, channel diversions, dikes and flood walls provide 

 a degree of flood control, but such measures do not conserve water. They do 

 not reduce the size of a flood, but merely ensure that water is safely passed 

 through any given locality. 



The Water Section of the conservation reports prepared for a number of 

 Conservation Authorities recommends the construction of a widespread system 

 of dams and reservoirs. Several of these dams have already been constructed 

 and a further number are now in the planning stages. 



Recommendations to Authorities with respect to flood control problems 

 usually include some or all of the following measures: 



( 1 ) reduction of peak stage by channel improvements 



(2) diversion of flood water through by-pass channels 



(3) confinement of the flow within dikes or flood walls 



(4) reduction of peak flow by reservoir 



(5) zoning or acquiring flood plains so that only low hazard uses are 

 permitted 



(6) flood forecasting coupled with a system to warn of impending danger 

 in sufficient time for protection or evacuation of the people and 

 valuable property 



The Fanshawe Dam and Reservoir is located on the north branch of the 

 Thames River a few miles upstream from the City of London. The reservoir, 

 completed in 1953, was built primarily for flood control and recreation. It re- 

 tains flows in excess of the channel capacity through the City of London, and 

 when the danger of flood is passed, the reservoir is lowered to its "recreation 



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