(1) The county within which each special district is located shall establish a system or systems of assessment for the special district as provided in this section. A differing system of assessment shall be established for different classes of facilities that a special district provides or will provide, including a separate system of assessment for diking and drainage facilities if both classes of facilities are provided. Whenever a special district is located in more than one county, the county within which the largest portion of the special district is located shall establish the system or systems of assessment for the entire special district. A system of assessment shall include assessment zones, the acreage included in each assessment zone, a dollar value of benefit or use per acre, and various classes or types of improvements together with a dollar value of benefit or use for an improvement included in each of the classes or types of improvements. The county shall establish which improvements shall be subject to special assessments and shall establish one or more types or classes of such improvements.

(2) The engineer of the county shall prepare a preliminary system or systems of assessment for each special district. Each system of assessment that is prepared for a special district shall be designed to generate a total of one thousand dollars in revenue for the special district.

The preliminary system or systems of assessment shall be filed with the county legislative authority. A public hearing on the preliminary system or systems of assessment shall be held by the county legislative authority. Notice of the public hearing shall be published in a newspaper, in general circulation in the special district, for two consecutive weeks with the final notice being published not less than fourteen, nor more than twenty-one days, before the public hearing. Notice shall also be mailed to each owner or reputed owner, as shown on the assessor's tax rolls, of each lot or parcel subject to such assessments. The mailed notice shall indicate the amount of assessment on the lot or parcel that, together with all other assessments in the system of assessment, would raise one thousand dollars. The mailed notice shall indicate that this assessment amount is not being imposed, but is a hypothetical assessment that, if combined with all other hypothetical assessments in the system of assessment, would generate one thousand dollars, and that this hypothetical assessment is proposed to be used to establish a system or systems of assessment for the special district. Where a special district currently is imposing special assessments and a property owner's property is subject to these special assessments, the mailed notice to this property owner also shall use the hypothetical special assessment in conjunction with the total special assessments imposed by the special district in that year to provide a comparison special assessment value to the property owner. This notice shall indicate that the comparison special assessment value is not being imposed, and should be considered for comparative purposes only. Where a special district is not currently imposing special assessments, the mailed notice may include, if deemed appropriate by the county engineer and if such figures are available, an estimated special assessment value for the property owner's property using this hypothetical special assessment in conjunction with special district-wide level of special assessments that possibly would be imposed in the following year. Where a county is imposing rates and charges for stormwater or surface water control facilities pursuant to chapters 36.89 or 36.94 RCW, the county shall credit such rates and charges with assessments imposed under this section by a special district to fund drainage facilities and the maintenance of drainage facilities.

(3) The county legislative authority shall hold a public hearing on the preliminary system or systems of assessment on the day specified in the notices. Persons objecting to the preliminary system or systems of assessment may present their objections at this public hearing, which may be continued if necessary. The county legislative authority shall adopt an ordinance finalizing the system or systems of assessment after making any changes that in its discretion are necessary. The county legislative authority shall have broad discretion in establishing systems of assessment. The decision of the county legislative authority shall be final, except for appeals. Any person objecting to the system or systems of assessment must appeal such decision to the superior court of the county within which all, or the largest portion, of the special district is located within twenty days of the adoption of the ordinance.

(4) The system or systems of assessment of each special district shall be reviewed by the county engineer and finalized by the county legislative authority at least once every four years. A system or systems of assessment shall be finalized on or before the first of September in the year that it is finalized. The legislative authority of a county that is responsible for establishing a system or systems of assessment for more than one special district may, at its option, stagger the initial finalization of such systems of assessment for different special districts over a period of up to four years. Assessments shall be collected in special districts pursuant to the district's previous system of assessment until the system or systems of assessment under this chapter is finalized under this section.

(5) New improvements shall be noted by the special district as they are made and shall be subject to special assessments in the year after the improvement is made.

(6) The county legislative authority, upon request by a special district, may authorize the special district to impose and collect emergency assessments pursuant to the special district's system or systems of assessment whenever the emergent protection of life or property is necessary.