All penalties hereafter collected and all penalties heretofore collected, which may be identified, by any county treasurer of the State of Oklahoma, on any delinquent assessments for any drainage shall be paid and credited to the funds of such drainage district, and shall be used only in the payment of the warrants or bonds and the interest thereon, issued for the construction of the improvement for which such assessments were made.
Laws 1933, c. 58, p. 106, § 4.