In order to finance the cost of installing any improvement for waterworks or water systems authorized by ORS 225.020 (Ownership and operation of utilities by city within and without city limits), a city council may provide for and make a local assessment for benefits, for all or part of the cost of such construction, against any and all property whether within or without the city or partially within or partially without the city and enforce collection of such assessments. An assessment shall not be levied under this section against property located outside the city, however, unless the governing body of the county where such property is located, by resolution, approved the assessment of the property to be assessed.