Del. Code tit. 9 § 4613
The preliminary expenses incurred for the preparation of maps, plans, studies, reports and other matters relating to the establishment or extension of a sewer district as authorized by this chapter, shall be a county charge and shall be assessed, levied and collected in the same manner as other county charges. If the county government shall thereafter establish or extend a sewer district and construct a sewer system therein pursuant to the provisions of this chapter, the expenses incurred by the county government as set forth above shall be deemed to be part of the cost of such improvement and the County shall be reimbursed for the whole amount paid therefor, or for such portion of that amount which the county government shall allocate against such district or extension. In the event the district is not established or extended, the county government may issue bonds to finance the above cost either in whole or in part, pledging the full faith and credit of the County to the punctual payment of the bonds and the interest thereon. Such bonds may be issued for a period of not to exceed 5 years from their respective dates.
9 Del. C. § 4613