Section 523 - Maintenance of improvements(a) Upon the certification by the Department of Transportation that the improvement or improvements have been satisfactorily completed, the improvement or improvements shall be incorporated into the state highway system, and the Department shall be responsible for the maintenance of the improvement or improvements, to include the replacement of street signs on any portion thereof when deemed necessary.(b) All roads and streets constructed pursuant to this chapter, not dedicated for public use and intended to be private, as indicated on the filing plan, shall be constructed in accordance with rules and regulations adopted by the county in which such road or street is located. Such rules and regulations for construction of private subdivision streets and roads shall, in addition to specifying standards for the design and construction thereof, require that, simultaneous with the construction of such streets and roads, a means or mechanism be provided to insure the perpetual maintenance of such private streets and roads, but in no event shall the State or county be responsible for such maintenance.45 Del. Laws, c. 123, § 19; 9 Del. C. 1953, § 523; 53 Del. Laws, c. 255; 59 Del. Laws, c. 180, § 4; 60 Del. Laws, c. 503, § 22; 64 Del. Laws, c. 357, §2.;