Disadvantages of Underground Transmission over Overhead Transmission. 1  Underground transmission line cable is costlier than overhead transmission. 2  The maintenance cost of underground cables is higher than over head transmission. 3  Capital cost of Overhead Transmission lines are cheaper than underground transmission line.
the average annual rainfall for Canada is 60.33 cm. That is alot! Any average is going to be a meaningless because Canada covers over 9 million sq/kms, extending from the Nor â¦ th Pole to below the 49th parallel and both east and west coasts of North America.
Toronto experiences some seasonal variation in monthly rainfall. The rainy period of the year lasts for 11 months, from February 7 to January 21, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around September 24, with an average total accumulation of 2.1 inches.