In all local improvement assessment districts in any assessing district in this state, property in such district, held or owned by the state shall be assessed and charged for its proportion of the cost of such local improvements in the same manner as other property in such district, it being the intention of this chapter that the state shall bear its just and equitable proportion of the cost of local improvements specially benefiting lands of the state. However, none of the provisions of this chapter shall have the effect, or be construed to have the effect, to alter or modify in any particular any existing lease of any lands or property owned by the state, or release or discharge any lessee of any such lands or property from any of the obligations, covenants, or conditions of the contract under which any such lands or property are leased or held by any such lessee.