The treasurer shall keep a bond fund account into which shall be covered all moneys arising from the sale of refunding bonds and sufficient money arising from assessment and levy to meet the next installment of principal and interest upon the bonds of the district. From the fund the treasurer shall pay the principal and interest on bonds as they mature and the bonds and interest coupons are presented. Moneys received from the sale of bonds other than refunding bonds, and otherwise for the construction and acquisition of works and all other moneys whatsoever shall be covered into a general fund from which shall be defrayed all obligations of the district other than those in this section above described.