Grain Guide 2018

How much water is in my dam? MOISTURE CONTENT ON DELIVERY Grain is seldom sold at the standard moisture content. When the moisture content is greater than the standard, the weight of the grain is discounted to make provision for the additional moisture. The following moisture content standards are used as condition for the delivery of commodities at silos: Delivered Agreed standard Sorghum Wheat Maize Soybeans Sunflower Groundnuts Canola Barley Oats For example: Maize is delivered at a moisture content of 14%. Formula: (100% - delivery %)  (100% - standard %) =  (100% - 14%)  (100% - 12,5%) 86% =   87,5% = 0,9828 By multiplying the weight of the grain delivered by 0,9828, the weight of the maize is calculated at a moisture content of 12,5%, for example the weight of a load of maize of 32 000 kg delivered at 14% moisture is (32 000 kg x 0,9828) 31 449,6 kg @ 12,5% moisture content.   ≤ 14% 12,5% – dry   ≤ 13%   ≤ 14% 12,5% – dry   ≤ 13% 12% – dry   ≤ 10% 9% – dry   ≤ 7%   ≤ 8%   ≤ 13%   ≤ 13% There are a few measurements that you need:  Surface area  Maximum depth Surface area The surface area of a dam is calculated by multiplying the length by the width. This will be the case for square or rectangular dams. Most dams start out as a square or rectangle, but over time appear to become rounded. If the dam is not exactly square, round the measurements off. Make sure to err on the conservative side. Dams such as Turkey Nest dams (used to store water on a relatively flat terrain) can be any shape, and their dimensions may need to be approximated to calculate the surface area. Gully dams (used to store water in a gully) can also be of varying shapes and the formula for calculating their storage capacity is discussed later. Volume With the surface area depth calculated, the volume can then be determined: (Where 0,4 accounts for the batter slope on the sides of the dam) Turkey Nest dam Gully dam Example: 30 metres x 50 metres = 1 500 m 2 Volume (m 3 ) = Surface Area (m 2 ) x Max depth (m) x 0,4 8 7 Relevant