I have recently received calls from growers who use surface water to irrigate produce crops. Their concern was that the results of their current water tests were very different from their last tests and that levels of indicator organisms appeared to have increased dramatically. Ponds and lakes that are used for irrigation can be very dynamic. Research has shown that levels of indicator organisms can change dramatically in a very short time. Because surface water is open to the environment and unprotected, changes in temperature and weather can affect ponds and lakes. During the spring and autumn seasons, ponds and lakes undergo inversions, stirring up sediments that have settled on the bottom of the pond. Rainfall can also cause bottom sediments to be stirred up. Bottom sediments may contain any number of materials. Soil particles from runoff are one of the primary components. Decaying bits of plant and animal debris may also be found in bottom[Read More…]