Hydrometeoro!ogy and Flood Warning 



Variations in meteorological conditions have a pronounced effect on the flow 

 pattern of the streams and rivers of Southern Ontario. Problems concerning the 

 relationship between meteorology and hydrology must be considered in detail 

 before control works can be established on a river. Hydrometeorological analyses 

 are therefore an important part of the water studies undertaken by the 

 Conservation Branch. 



An extensive network of precipitation and stream gauge stations has been 

 established on the watersheds in Southern Ontario. Data from these stations are 

 used to relate rainfall, snowmelt and soil moisture conditions to run-off. Such 

 studies establish the characteristic of the stream under a variety of meteorological 

 conditions. These studies are necessary to establish the capacity of reservoirs, the 

 size and type of dam structures or channel improvements, and the availability of 

 water for a number of uses. 



The need for a flood warning system in Ontario became abundantly clear 

 following the disaster caused by Hurricane Hazel in 1954. In 1955 the 

 Meteorological Branch of the Canada Department of Transport seconded a 

 meteorologist to the Conservation Authorities Branch to establish a flood warning 

 system. The hydrometeorologist is responsible for maintaining a watch over 

 conditions, issuing flood forecasts, supervising the operation of flood control 

 reservoirs and establishing meteorological design criteria for river control structures. 



A basic feature of the flood warning system is the close co-operation between 

 the Federal Government department responsible for weather forecasts and the 

 Provincial Government department responsible for river control. The 

 Meteorological Branch of the Canada Department of Transport, which is 

 responsible for weather forecasting in Canada, issues the necessary weather data, 

 weather forecasts, and warnings of severe weather conditions. The Conservation 

 Authorities Branch applies this weather information to conditions existing on the 

 watersheds and issues flood forecasts based on the results of the correlation of 

 these two types of information. 



SOIL CONSERVATION AND LAND USE 



Authority projects in soil conservation form an important part of the overall 

 program. The nature of these projects, however, is such that they are often less 

 spectacular and hence less noticed than flood control structures or conservation 

 and recreation projects. 



The use and management of soil is primarily the concern of the individual 

 landowner. The major Government responsibility for assisting agriculture is 

 vested in the Department of Agriculture. Conservation Authorities tend to limit 

 soil conservation programs to publicizing the need for, and the value of, good soil 

 management. In their programs, the Authorities work in close co-operation with 

 the Department of Agriculture and the Ontario Agricultural College. The County 

 Agricultural Representatives are usually members of the Authorities' land use 

 advisory boards. 



FARM PONDS 



Two-thirds of the Conservation Authorities give financial and technical 

 assistance to farm pond design and construction. Financial assistance is given in 



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