1. In assessing the benefits to lands, public highways, railroad and other rights-of-way, railroad roadways and other property not traversed by the improvements, the viewers shall not consider what benefits will be derived by such property after other ditches or improvements shall have been constructed, but they shall assess only such benefits as will be derived from the construction of the improvements to be constructed by this district, or as the same may afford an outlet for drainage or protection from overflow of or damage to such property.

2. The viewers shall give due consideration and credit to any other drains, ditch or ditches, levee or levees which may have already been constructed and which afford partial or complete protection to any tract or parcel of land in the new district.

3. The public highways, railroad and other rights-of-way, roadways, railroad and other property shall be assessed according to the increased physical efficiency and decreased maintenance cost of roadways by reason of the protection to be derived from the proposed improvements.

4. When part of a tract of land is to be acquired by the district for right-of-way or other purposes, the viewers shall list the remainder of the tract in the schedule of benefits, and show the acreage remaining and shall estimate the benefits which will accrue to same.