# Mass Balance

The mass balance equation for sediment in a water body is:

&#x20;     $$sed_{wb}=sed_{wb,i}+sed_{flowin}-sed_{stl}-sed_{flowout}$$                          8:2.1.1

where $$sed_{wb}$$ is the amount of sediment in the water body at the end of the day (metric tons), $$sed_{wb,i}$$ is the amount of sediment in the water body at the beginning of the day (metric tons), $$sed_{flowin}$$ is the amount of sediment added to the water body with inflow (metric tons), $$sed_{stl}$$ is the amount of sediment removed from the water by settling (metric tons), $$sed_{flowout}$$ is the amount of sediment transported out of the water body with outflow (metric tons).
