If any drainage district organized under the provisions of this act shall include a smaller district previously organized under the laws of this state, the provisions of this act shall apply to all matters of drainage recited herein within said smaller district, and the board of directors of any drainage district so organized under this act shall have charge thereof: Provided, That if any work of a permanent nature, such as is described in Kan. Stat. Ann. § 24-501, has been done by said smaller district, a value shall be placed upon said work by the benefits and damages commission provided for in this act, and the value thus fixed shall be paid by the larger drainage district aforesaid. But as to all matters not included within the provisions of this act said smaller district may remain a separate and distinct organization.