For all riparian zones an exception to any of the disturbances listed in Pragraph a2 above shall be granted by the Zoning Board of Adjustment upon proof by virtue of submission of appropriate maps, drawings, reports and testimony, that the disturbance protects public health, safety or welfare; provides an environmental benefit; prevents extraordinary hardship on the property owner peculiar to the property; or prevents extraordinary hardship, provided that the hardship was not created by the property owner, that would not permit a minimum economically viable use of the property based upon reasonable investment.