Accumulated snow of the city street

Accumulated snow of the city street is mainly caused by removing the snow from the road and from the roof. Accordingly various factors as shown below influence the accumulated snow of the city street. 1. degree of the snowfalling in cold spell 2. width of the road 3. density of the house distribution in the area 4. existence of houses so constructed as to withstand snow weight 5. traffic volume etc. On the other hand, ability of the snow removal or snow melting influence the accumulation of snow. In snowy districts, the road has extra zones on each side for the purpose of snow removal and snow accumulation, which are called road snow accumulation zones. First, we Observed the formation process, construction, volume, mean density of the accumulated snow formed on the sides of the road. The volume of accumulated snow changes according to the weather conditions the intensity and interval of snow falling and air temperature of the year and the interval of operating snow removal machines. We found that its maximum value can be calculated by measuring the maximum weight of the snow cover of the year. The density of the accumulated snow increases according to the next conditions 1. Compression by snow plows while removing snow 2. Increase of density by the repetition of melting and freezing 3. Compression caused by the weight of accumulated snow By our measurements during 1979-1980 winter, we got the following results. 1) In the first half of January when the air temperature was low and we had many snowy days, we obtained 0.2-0.25 t/m^3 average density of accumulated snow. 2) At the end of January, ca 0.37. 3) When the maximum snow depth of the winter was observed, the volume of accumulated snow was the greatest and we obtained ca.0.4 then. 4) When the maximum weight of the snow cover of the winter was observed, the weight of accumulated snow was the greatest, and we observed ca.0.45. 5) The average density of accumulated snow showed approximately the same value regardless of the width of the road. 6) The density of each part of the cross section of the accumulated snow was of random distribution. Its values ranged from 0.34 to 0.69. 7) The average density of the accumulated snow was always greater than the average density of natural snow cover, but in the thawing season, they came to almost the same value. From these results, we can estimate the density of the accumulated snow al each period of the winter. Now we know that the weight of the accumulated snow can be calculated from the weight of snow cover and the width of the road, so by determining the weight and the average density of the accumulated snow we can calculate its volume. By this way we compared the calculated volume of the accumulated snow with the measured volume. The measured value was obtained through the questionnaires given to 600 junior high students. From this comparison we found that the measured value was smaller than the calculated value. The calculated value is originally obtained based on the observation values at appointed places, so it should agree with the measured value in the questionnaires. But they didn't agree. The disagreement was caused by clearing various parts of the city of snow and melting snow by snow pipe. From the questionnaires we found that the amount of the disposed accumulated snow per house by clearing and melting was ca.1.5-2 m^3