(1) The total annual special assessments may not exceed the estimated cost of the lake or beach improvement or maintenance activities proposed to be financed by such special assessments, as specified in the resolution of intention. The total of special assessments imposed in a lake or beach management district that are of the nature of special assessments imposed in a local improvement district shall not exceed one hundred fifty percent of the estimated total cost of the lake or beach improvement or maintenance activities that are proposed to be financed by the lake or beach management district as specified in the resolution of intention.

(2) After a lake or beach management district has been created, the resolution of intention may be amended to increase or otherwise modify the amount to be financed by the lake or beach management district by using the same procedure in which a lake or beach management district is created, including landowner approvals consistent with the procedures established in RCW 36.61.080 through 36.61.100.