BLACKBURG, Virginia: A study was conducted by Virginia Tech to determine if the installation of an off stream water source could substitute for stream bank fencing. The study was conducted on two Southwest Virginia farms practicing rotational grazing.

The study found that the presence of an off stream water source did in fact greatly reduce the negative impact which grazing cattle have upon stream bank erosion and water quality.

Field observations of cattle behaviour indicated that cattle preferred to drink from an off stream water source over that of an adjacent stream 92 percent of the time.

The installation of an off stream water source reduced the total time cattle spent within the stream area by 58 percent and the amount of stream bank erosion by 76 percent.

Due to the installation of off stream water sources, concentration of total phosphorous and sediment bound phosphorous were reduced by 90, 54, 70, 68, 81 and 75 percent respectively.

Concentration of fecal coliform and fecal streptococci decreased by 51 and 77 per cent when an off stream water source was available for grazing cattle.

Lastly, an economic analysis of the data indicated that the cost of developing off stream water sources was considerably less than that of implementing six fenced bank buffer zones scenarios on the two farms.