The board of ditch commissioners may deem adequate any works of improvement already constructed, including but not limited to ditches and structures and may incorporate these in the tax ditch, and may allow a fair compensation to landowners for work previously done by them on such works of improvement.

48 Del. Laws, c. 151, § ?17; 7 Del. C. 1953, § ?4127; 50 Del. Laws, c. 276, § ?10;