Any irrigation district shall have the power to establish utility local improvement districts within its territory and to levy special assessments within such utility local improvement districts in the same manner as provided for irrigation district local improvement districts: PROVIDED, That it must be specified in any petition for the establishment of a utility local improvement district that the sole purpose of the assessments levied against the real property located within the utility local improvement district shall be the payment of the proceeds of those assessments into a revenue bond fund for the payment of revenue bonds, that no warrants or bonds shall be issued in any such utility local improvement district, and that the collection of interest and principal on all assessments in such utility local improvement district, when collected, shall be paid into that revenue bond fund, except that special assessments paid before the issuance and sale of bonds may be deposited in a fund for the payment of costs of improvements in the utility local improvement district.