From and after the date of transfer such flood control district is solely liable for the payment of the principal upon the general obligation bonds of any such drainage improvement district and upon bonds of such district secured by and payable out of a fund derived from specific or direct assessments which are a lien upon particular parcels of land, issued pursuant to the Improvement Bond Act of 1915, and for the payment of interest upon the bonded debt of any such drainage district represented by coupons maturing subsequent to the date of transfer.