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.
The tables below give yearly averages for rainfall plus snowfall at cities and towns in British Columbia. Each place has a total for how many days of wet weather it usually gets a year and for the normal amount of precipitation.The calculation of days only includes the days when precipitation totalled at least 0.2 millimetres (0.008 inches).ou can jump to a separate table for each section of the province: Southwest Mainland, Gulf Islands, Vancouver Island, Central BC, Southeast BC and Northern BC.