=+44. Nonpoint source loads are chemical masses that travel to the main stem of a river and its tributaries in flows that are distributed over relatively long stream reaches in contrast to those that enter at well-defined and regulated points. The article “Assessing Uncertainty in Mass Balance Calculation of River Nonpoint Source Loads” (J. of Envir. Engr., 2008: 247–258)

suggested that for a certain time period and location, x 5 nonpoint source load of total dissolved solids (in kg/day/km) could be modeled with a lognormal distribution having  5 9.164 and  5 .385.