This Chapter of the Revised Code of Washington (RCW) concerns river and harbor improvements. Specifically, it provides for improvement commission, appointment, oath; improvement commission, notification of appointment, organization; establishment of assessment district, assessments, state lands; assessment roll; hearing on roll, date, notice; hearing on roll, objections, certification for collection; appeal from final assessment; lien of assessment, collection, payment, interest; local improvement fund, disbursements; bonds, issuance, sale, form; bonds, execution; payment in full, calls for bonds, notice, bond owners' rights; improvement by counties jointly; improvement by counties jointly, procedure; improvement by counties jointly, joint board of equalization; improvement by counties jointly, joint assessment roll, filing, appeals, subsequent proceedings; improvement by counties jointly, expenses of joint board; joint aid river and harbor improvements, bonds, election; joint aid river and harbor improvements, declared county purpose; joint planning for improvement of navigable river, development of river valley; and joint planning for improvement of navigable river, contract, joint board to control and direct work.