All but one is a technique that can be used to prevent agricultural impacts on the great lakes waterways. a) diverting the flow of waterways to prevent them from coming in contact with agricultural lands. b) cover crops are used to keep soil on the field during the non-growing season while improving soil health. c) placed along waterways or drainage ditches, buffer strips can catch and retain sediment and excess nutrients. d) conservation tillage: this is a practice that maintains a layer of vegetative residue that can to protect the soil from erosion.