Del. Code tit. 17, § 902

The Department shall, at all times, cause suitable and sufficient ditches or other conduits to be constructed along the right-of-way of any road or highway constructed, altered or changed, whereby, because of such construction, alteration or changing of such lands included in the right-of-way of such road or highway, the natural contour lines and levels of the lands included within such right-of-way of such road or highway would be changed, and waters would tend to collect upon and over the lands adjacent to such road or highway because of such change.