(1) When real property is divided in accordance with chapter 58.17 RCW, the assessor shall carefully investigate and ascertain the true and fair value of each lot and assess each lot on that same basis, unless specifically provided otherwise by law. For purposes of this section, "lot" has the same definition as in RCW 58.17.020.

(a) The assessor must establish the true and fair value by October 30th of the year following the recording of the plat, replat, or altered plat. The value established must be the value of the lot as of January 1st of the year the original parcel of real property was last revalued.

(b) For purposes of this section, "subdivision" means a division of land into two or more lots.

(c) For each subdivision, all current year and delinquent taxes and assessments on the entire tract must be paid in full in accordance with RCW 58.17.160 and 58.08.030 except when property is being acquired by a government for public use. For purposes of this section, "current year taxes" means taxes that are collectible under RCW 84.56.010 subsequent to completing the tax roll for current year collection.

(2) When the assessor is required by law to segregate any part or parts of real property, assessed before or after July 27, 1997, as one parcel or when the assessor is required by law to combine parcels of real property assessed before or after July 27, 1997, as two or more parcels, the assessor must carefully investigate and ascertain the true and fair value of each part or parts of the real property and each combined parcel and assess each part or parts or each combined parcel on that same basis.