The following report on snow cover depletion deals with only a small part of an overall program to predict runoff from snowmelt. When an adequate means of snowmelt-streamflow forecasting is available, the basis will be established to estimate suspended sediment and bed load movements for a certain region by measuring the meteorological parameters causing snowmelt. One of the main variables which has to be estimated during periods of runoff is the amount of area actually contributing to runoff.

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... ost of the snowmelt equations, for example UNITED STATES CORPS OF ENGINEERS (1965) generalized snowmelt equations, compute the amount of melt in inches of water equivalent per day for a snow-covered area. To commence studies in this region to estimate the amount of snow cover, a flight was made over the North Nashwaaksis Stream Basin near Fredericton, New Brunswick (Figure 1 ). This basin was chosen for the study as it has been designated as a representative watershed for the International Hydrological Decade (reported in Maritime Sediments, 2-ii 79-81, April 1966). Consequently, the basin has accurate measurements of the major hydrometeorological elements for the last 10 months. On 5 April 1966, photographs of the basin were taken from a height of approximately 1500 feet above ground from a light aircraft as it made a circuit around the basin divide. The aircraft was not equipped to take vertical photographs, so oblique ones were taken for the initial phase of the study. Most of the basin is forest covered, and it was difficult to determine surface conditions from the oblique photographs where the cover was dense. To overcome this difficulty, it is suggested that future flights be made at a higher altitude and than an attempt be made to take vertical photographs. Since the only areas that could be interpreted easily were the open areas, this study was limited to snow cover depletion in open fields In the forested areas that could be examined adequately in the photographs, it was observed that the ground was completely covered with snow.